Multigigabit W-Band (75–110 GHz) Bidirectional Hybrid Fiber-Wireless Systems in Access Networks

DEFF Research Database (Denmark)

Pang, Xiaodan; Lebedev, Alexander; Vegas Olmos, Juan José

2014-01-01

compare the transmission performances in terms of achievable wireless distances with and without using a high-frequency electrical power amplifier at the wireless transmitter. A downlink 16-Gbit/s QPSK signal and an uplink 1.25-Gbit/s ASK signal transmission over the two implementations are experimentally......We experimentally demonstrate multigigabit capacity bidirectional hybrid fiber-wireless systems with RF carrier frequencies at the W-band (75-110 GHz) that enables the seamless convergence between wireless and fiber-optic data transmission systems in access networks. In this study, we evaluate...... the transmission performances in two scenarios: a fiber-wireless access link that directly provide high-speed connections to wireless end users, and a fiber-wireless-fiber signal relay where a high capacity wireless link can be used to bridge two access fiber spans over physical obstacles. In both scenarios, we...

Multiple access protocol for supporting multimedia services in wireless ATM networks

DEFF Research Database (Denmark)

Liu, Hong; Dittmann, Lars; Gliese, Ulrik Bo

1999-01-01

The furture broadband wireless asynchronous transfer mode (ATM) networks must provide seamless extension of multimedia services from the wireline ATM networks. This requires an effecient wireless access protocol to fulfill varying Quality-og-Service (QoS) requirements for multimedia applications....... In this paper, we propose a multiple access protocol using centralized and distributed channel access control techniques to provide QoS guarantees for multimedia services by taking advantage of the characteristics of different kinds of ATM traffics. Multimedia traffic, including constant bit rate (CBR...

An Experimental Performance Measurement of Implemented Wireless Access Point for Interworking Wi-Fi and HSDPA Networks

Science.gov (United States)

Byun, Tae-Young

This paper presents a prototype of WAP(Wireless Access Point) that provides the wireless Internet access anywhere. Implemented WAP can be equipped with various wireless WAN interfaces such as WCDMA and HSDPA. WAP in the IP mechanism has to process connection setup procedure to one wireless WAN. Also, WAP can provide connection management procedures to reconnect interrupted connection automatically. By using WAP, several mobile devices such as netbook, UMPC and smart-phone in a moving vehicle can access to HSDPA network simultaneously. So, it has more convenient for using the WAP when there are needs to access wireless Internet more than two mobile devices in restricted spaces such as car, train and ship.

Efficient scheduling request algorithm for opportunistic wireless access

KAUST Repository

Nam, Haewoon; Alouini, Mohamed-Slim

2011-01-01

An efficient scheduling request algorithm for opportunistic wireless access based on user grouping is proposed in this paper. Similar to the well-known opportunistic splitting algorithm, the proposed algorithm initially adjusts (or lowers

Fixed Access Network Sharing

Science.gov (United States)

Cornaglia, Bruno; Young, Gavin; Marchetta, Antonio

2015-12-01

Fixed broadband network deployments are moving inexorably to the use of Next Generation Access (NGA) technologies and architectures. These NGA deployments involve building fiber infrastructure increasingly closer to the customer in order to increase the proportion of fiber on the customer's access connection (Fibre-To-The-Home/Building/Door/Cabinet… i.e. FTTx). This increases the speed of services that can be sold and will be increasingly required to meet the demands of new generations of video services as we evolve from HDTV to "Ultra-HD TV" with 4k and 8k lines of video resolution. However, building fiber access networks is a costly endeavor. It requires significant capital in order to cover any significant geographic coverage. Hence many companies are forming partnerships and joint-ventures in order to share the NGA network construction costs. One form of such a partnership involves two companies agreeing to each build to cover a certain geographic area and then "cross-selling" NGA products to each other in order to access customers within their partner's footprint (NGA coverage area). This is tantamount to a bi-lateral wholesale partnership. The concept of Fixed Access Network Sharing (FANS) is to address the possibility of sharing infrastructure with a high degree of flexibility for all network operators involved. By providing greater configuration control over the NGA network infrastructure, the service provider has a greater ability to define the network and hence to define their product capabilities at the active layer. This gives the service provider partners greater product development autonomy plus the ability to differentiate from each other at the active network layer.

Knowledge-Based Multiple Access Protocol in Broadband Wireless ATM Networks

DEFF Research Database (Denmark)

Liu, Hong; Gliese, Ulrik Bo; Dittmann, Lars

1999-01-01

In this paper, we propose a knowledge-based multiple access protocol for the extension of wireline ATM to wireless networks. The objective is to enable effecient transmission of all kinds of ATM traffic in the wireless channel with guaranteed QoS.The proposed protocol utilixes knowledge of the main...... guaranteed QoS requirements to a variety of ATM applications....

Heterogeneous wireless/wireline optical access networks with the R-EAT as backend component

Science.gov (United States)

Hagedorn, Klaus; Gindera, Ralf; Stohr, Andreas; Jager, Dieter

2004-09-01

A heterogeneous wireless/wireline optical transmission link using a reflection type electroabsorption transceiver (R-EAT) is presented. Simultaneous transmission of full-duplex broadband wireless LAN (WLAN) channels and 1Gb/s base band data is experimentally demonstrated. The system link employs sub-carrier multiplexing (SCM) and two optical channels for full duplex transmission of various analog WLAN channels and downlink digital base band data. The developed link architecture is suitable for simultaneous transmission of broadband wireline and wireless signals, it enables the coexistence and interoperability between wireline and wireless access technologies. The developed R-EAT component employed in this wireline/wireless access system, features "single-chip-component" base stations in access networks with star type topology where only a single optical fiber is used for bidirectional optical transmission. The R-EAT can be used within the optical C-band (1530- 1560nm) and is suitable for (D)WDM networks. Bit error rate measurements demonstrate the capabilities of the R-EAT for 1Gb/s base band transmission. The analog performance for WLAN transmission is characterised by a spurious free dynamic range (SFDR) of more than 75dB and 90dB for uplink and downlink transmission, respectively. The link gain for uplink and downlink transmission is -42dB and -37dB, respectively. The demonstrates the analog performances of the R-EAT for being used in wireless access networks such as W-LAN.

Wireless access to a pharmaceutical database: A demonstrator for data driven Wireless Application Prorocol (WAP) applications in medical information processing

DEFF Research Database (Denmark)

Hansen, Michael Schacht; Dørup, Jens

2001-01-01

script for easy update of the database. Data were distributed in 35 interrelated tables. Each pharmaceutical brand name was given its own card with links to general information about the drug, active substances, contraindications etc. Access was available through 1) browsing therapeutic groups and 2......) searching for a brand name. The database interface was programmed in the server-side scripting language PHP3. RESULTS: A free, open source Wireless Application Protocol gateway to a pharmaceutical catalogue was established to allow dial-in access independent of commercial Wireless Application Protocol...... service providers. The application was tested on the Nokia 7110 and Ericsson R320s cellular phones. CONCLUSIONS: We have demonstrated that Wireless Application Protocol-based access to a dynamic clinical database can be established using open source freeware. The project opens perspectives for a further...

Integrated Coherent Radio-over-Fiber Units for Millimeter-Wave Wireless Access

DEFF Research Database (Denmark)

Stöhr, A.; Babiel, S.; Chuenchom, M.

2015-01-01

For providing wireless access as a complementary access technology to direct optical access, supporting 1–10 Gb/s per client, we propose a novel scheme based upon the transparent integration of coherent Radio-over-Fiber (CRoF) units with next generation optical access (NGOA) networks using dense ...

Combined single-mode/multimode fiber link supporting simplified in-building 60-GHz gigabit wireless access

DEFF Research Database (Denmark)

Pham, Tien Thang; Lebedev, Alexander; Beltrán, Marta

2012-01-01

In this paper, we propose and experimentally demonstrate a simple, cost-effective hybrid gigabit fiber-wireless system for in-building wireless access. Simplicity and cost-effectiveness are achieved in all parts of the system by utilizing direct laser modulation, optical frequency up-conversion, ......In this paper, we propose and experimentally demonstrate a simple, cost-effective hybrid gigabit fiber-wireless system for in-building wireless access. Simplicity and cost-effectiveness are achieved in all parts of the system by utilizing direct laser modulation, optical frequency up...

The Making of a Sustainable Wireless City? Mapping Public Wi-Fi Access in Shanghai

Directory of Open Access Journals (Sweden)

Mingfeng Wang

2016-01-01

Full Text Available In the context of the global information economy, ready access to the Internet is critical to a city’s competitiveness, which has prompted a number of cities to launch plans to establish wireless networks. Most literature on the development of wireless cities focuses on cities in Western countries, and few have discussed how Chinese cities have adopted wireless technologies in their urban infrastructure development efforts. This paper examines recent development and spatial distribution of public Wi-Fi access in Shanghai, a leading business hub in China. We mapped Wi-Fi hotspots through the government sponsored “i-Shanghai” project and China Mobile Communications Corporation (CMCC. We find that while telecommunication providers have been proactively deploying WLAN (wireless local area network，a proxy of public Wi-Fi or wireless access hotspots in Shanghai, neither government sponsored WLAN hotspots nor facilities established by CMCC could cover the old traditional neighborhoods in the central city and sub-districts in remote rural areas. We also address the development of a more sustainable wireless city in Shanghai with a particular focus on digital divide and social equity issues.

Centralized optical-frequency-comb-based RF carrier generator for DWDM fiber-wireless access systems

DEFF Research Database (Denmark)

Pang, Xiaodan; Beltran, Marta; Sanchez, Jose

2014-01-01

In this paper, we report on a gigabit capacity fiber-wireless system that enables smooth integration between high-speed wireless networks and dense wavelength-division-multiplexing (DWDM) access networks. By employing a centralized optical frequency comb, both the wireline and the wireless services...

Millimeter Wave Hybrid Photonic Wireless Links for High-Speed Wireless Access and Mobile Fronthaul

DEFF Research Database (Denmark)

Rommel, Simon

As the introduction of the fifth generation of mobile services (5G) is set to revolutionize the way people, devices and machines connect, the changes to the underlying networks and technologies are no less drastic. The massive increase in user and data capacity, as well as the decrease in latency...... networks. In summary, the work presented in this thesis has regarded a multitude of aspects of millimeter wave hybrid photonic wireless links, expanding upon the state of the art and showing their feasibility for use in fifth generation mobile and high speed wireless access networks – hopefully bringing...

Joint estimation and contention-resolution protocol for wireless random access

DEFF Research Database (Denmark)

Stefanovic, Cedomir; Trillingsgaard, Kasper Fløe; Kiilerich Pratas, Nuno

2013-01-01

We propose a contention-based random-access protocol, designed for wireless networks where the number of users is not a priori known. The protocol operates in rounds divided into equal-duration slots, performing at the same time estimation of the number of users and resolution of their transmissi......We propose a contention-based random-access protocol, designed for wireless networks where the number of users is not a priori known. The protocol operates in rounds divided into equal-duration slots, performing at the same time estimation of the number of users and resolution...... successive interference cancellation which, coupled with the use of the optimized access probabilities, enables throughputs that are substantially higher than the traditional slotted ALOHA-like protocols. The key feature of the proposed protocol is that the round durations are not a priori set...

Cross-layer optimization of wireless multi-hop networks

OpenAIRE

Soldati, Pablo

2007-01-01

The interest in wireless communications has grown constantly for the past decades, leading to an enormous number of applications and services embraced by billions of users. In order to meet the increasing demand for mobile Internet access, several high data-rate radio networking technologies have been proposed to offer wide area high-speed wireless communications, eventually replacing fixed (wired) networks for many applications. This thesis considers cross-layer optimization of multi-hop rad...

Wireless-accessible sensor populations for monitoring biological variables

NARCIS (Netherlands)

Mazzu, Marco; Scalvini, Simonetta; Giordano, A.; Frumento, E.; Wells, Hannah; Lokhorst, C.; Glisenti, Fulvio

2008-01-01

The current health-care infrastructure is generally considered to be inadequate to meet the needs of an increasingly older population. We have investigated the feasibility of a passive in-home monitoring system based on wireless accessible sensor populations (WASP). In an EU-funded project we have

ICSW2AN : An Inter-vehicle Communication System Using Mobile Access Point over Wireless Wide Area Networks

Science.gov (United States)

Byun, Tae-Young

This paper presents a prototype of inter-vehicle communication system using mobile access point that internetworks wired or wireless LAN and wireless WAN anywhere. Implemented mobile access point can be equipped with various wireless WAN interfaces such as WCDMA and HSDPA. Mobile access point in the IP mechanism has to process connection setup procedure to one wireless WAN. To show the applicability of the mobile access point to inter-vehicle communication, a simplified V2I2V-based car communication system called ICSW2AN is implemented to evaluate major performance metrics by road test. In addition, results of road test for traffic information service are investigated in view of RTT, latency and server processing time. The experimental result indicates that V2I2V-based car communication system sufficiently can provide time-tolerant traffic information to moving vehicles while more than two mobile devices in restricted spaces such as car, train and ship access wireless Internet simultaneously.

Delay-aware adaptive sleep mechanism for green wireless-optical broadband access networks

Science.gov (United States)

Wang, Ruyan; Liang, Alei; Wu, Dapeng; Wu, Dalei

2017-07-01

Wireless-Optical Broadband Access Network (WOBAN) is capacity-high, reliable, flexible, and ubiquitous, as it takes full advantage of the merits from both optical communication and wireless communication technologies. Similar to other access networks, the high energy consumption poses a great challenge for building up WOBANs. To shot this problem, we can make some load-light Optical Network Units (ONUs) sleep to reduce the energy consumption. Such operation, however, causes the increased packet delay. Jointly considering the energy consumption and transmission delay, we propose a delay-aware adaptive sleep mechanism. Specifically, we develop a new analytical method to evaluate the transmission delay and queuing delay over the optical part, instead of adopting M/M/1 queuing model. Meanwhile, we also analyze the access delay and queuing delay of the wireless part. Based on such developed delay models, we mathematically derive ONU's optimal sleep time. In addition, we provide numerous simulation results to show the effectiveness of the proposed mechanism.

Integrated control platform for converged optical and wireless networks

DEFF Research Database (Denmark)

Yan, Ying

The next generation of broadband access networks is expected to be heterogeneous. Multiple wired and wireless systems can be integrated, in order to simultaneously provide seamless access with an appropriate Quality of Service (QoS). Wireless networks support ubiquitous connectivity yet low data...... rates, whereas optical networks can offer much higher data rates but only provide fixed connection structures. Their complementary characteristics make the integration of the two networks a promising trend for next generation networks. With combined strengths, the converged network will provide both...... the complementary characteristics of the optical networks and the wireless networks, addresses motivations for their interworking, discusses the current progress in hybrid network architectures as well as the functionalities of a control system, and identifies the achieved research contributions in the integrated...

Service Class Resource Management For Green Wireless-Optical Broadband Access NetworksWOBAN

Directory of Open Access Journals (Sweden)

SRUTHY.S

2015-08-01

Full Text Available Abstract-Broadband access networks have become an essential part of worldwide communication systems because of the exponential growth of broadband services such as video on demand high definition TV internet protocol TV and video conferencing. Exponential growth in the volume of wireless data boosted by the growing popularity of mobile devices such as smartphone and tablets has forced the telecommunication industries to rethink the way networks are currently designed and to focus on the development of high-capacity mobile broadband networks. In response to this challenge researchers have been working toward the development of an integrated wireless optical broadband access network. Two major candidate technologies which are currently known for their high capacity as well as quality of service QoS for multimedia traffic are passive optical networks PON and fourth generation 4G wireless networks. PON is a wired access technology well known for its cost efficiency and high capacity whereas 4G is a wireless broadband access technology which has achieved broad market acceptance because of its ease of deployment ability to offer mobility and its cost efficiency. Integration of PON and 4G technologies in the form of wireless-optical broadband access networks offers advantages such as extension of networks in rural areas support for mobile broadband services and quick deployment of broadband networks. These two technologies however have different design architectures for handling broadband services that require quality of service. For example 4G networks use traffic classification for supporting different QoS demands whereas the PON architecture has no such mechanism to differentiate between types of traffic. These two technologies also differ in their power saving mechanisms. Propose a service class mapping for the integrated PON-4G network which is based on the MG1 queuing model and class-based power saving mechanism which significantly improves the

Medium Access Control in Energy Harvesting - Wireless Sensor Networks

DEFF Research Database (Denmark)

Fafoutis, Xenofon

Focusing on Wireless Sensor Networks (WSN) that are powered by energy harvesting, this dissertation focuses on energy-efficient communication links between senders and receivers that are alternating between active and sleeping states of operation. In particular, the focus lies on Medium Access...

Analysis of the Decoupled Access for Downlink and Uplink in Wireless Heterogeneous Networks

DEFF Research Database (Denmark)

Smiljkovikj, K.; Popovski, Petar; Gavrilovska, L.

2015-01-01

Wireless cellular networks evolve towards a heterogeneous infrastructure, featuring multiple types of Base Stations (BSs), such as Femto BSs (FBSs) and Macro BSs (MBSs). A wireless device observes multiple points (BSs) through which it can access the infrastructure and it may choose to receive th...

Adaptive Code Division Multiple Access Protocol for Wireless Network-on-Chip Architectures

Science.gov (United States)

Vijayakumaran, Vineeth

Massive levels of integration following Moore's Law ushered in a paradigm shift in the way on-chip interconnections were designed. With higher and higher number of cores on the same die traditional bus based interconnections are no longer a scalable communication infrastructure. On-chip networks were proposed enabled a scalable plug-and-play mechanism for interconnecting hundreds of cores on the same chip. Wired interconnects between the cores in a traditional Network-on-Chip (NoC) system, becomes a bottleneck with increase in the number of cores thereby increasing the latency and energy to transmit signals over them. Hence, there has been many alternative emerging interconnect technologies proposed, namely, 3D, photonic and multi-band RF interconnects. Although they provide better connectivity, higher speed and higher bandwidth compared to wired interconnects; they also face challenges with heat dissipation and manufacturing difficulties. On-chip wireless interconnects is one other alternative proposed which doesn't need physical interconnection layout as data travels over the wireless medium. They are integrated into a hybrid NOC architecture consisting of both wired and wireless links, which provides higher bandwidth, lower latency, lesser area overhead and reduced energy dissipation in communication. However, as the bandwidth of the wireless channels is limited, an efficient media access control (MAC) scheme is required to enhance the utilization of the available bandwidth. This thesis proposes using a multiple access mechanism such as Code Division Multiple Access (CDMA) to enable multiple transmitter-receiver pairs to send data over the wireless channel simultaneously. It will be shown that such a hybrid wireless NoC with an efficient CDMA based MAC protocol can significantly increase the performance of the system while lowering the energy dissipation in data transfer. In this work it is shown that the wireless NoC with the proposed CDMA based MAC protocol

Convergence of broadband optical and wireless access networks

Science.gov (United States)

Chang, Gee-Kung; Jia, Zhensheng; Chien, Hung-Chang; Chowdhury, Arshad; Hsueh, Yu-Ting; Yu, Jianjun

2009-01-01

This paper describes convergence of optical and wireless access networks for delivering high-bandwidth integrated services over optical fiber and air links. Several key system technologies are proposed and experimentally demonstrated. We report here, for the first ever, a campus-wide field trial demonstration of radio-over-fiber (RoF) system transmitting uncompressed standard-definition (SD) high-definition (HD) real-time video contents, carried by 2.4-GHz radio and 60- GHz millimeter-wave signals, respectively, over 2.5-km standard single mode fiber (SMF-28) through the campus fiber network at Georgia Institute of Technology (GT). In addition, subsystem technologies of Base Station and wireless tranceivers operated at 60 GHz for real-time video distribution have been developed and tested.

Wireless and wireline service convergence in next generation optical access networks - the FP7 WISCON project

DEFF Research Database (Denmark)

Vegas Olmos, Juan José; Pang, Xiaodan; Lebedev, Alexander

2014-01-01

The next generation of information technology demands both high capacity and mobility for applications such as high speed wireless access capable of supporting broadband services. The transport of wireless and wireline signals is converging into a common telecommunication infrastructure....... In this paper, we will present the Marie Curie Framework Program 7 project “Wireless and wireline service convergence in next generation optical access networks” (WISCON), which focuses on the conception and study of novel architectures for wavelength-division-multiplexing (WDM) optical multi-modulation format...

EAP-Kerberos: A Low Latency EAP Authentication Method for Faster Handoffs in Wireless Access Networks

Science.gov (United States)

Zrelli, Saber; Okabe, Nobuo; Shinoda, Yoichi

The wireless medium is a key technology for enabling ubiquitous and continuous network connectivity. It is becoming more and more important in our daily life especially with the increasing adoption of networking technologies in many fields such as medical care and transportation systems. Although most wireless technologies nowadays provide satisfying bandwidth and higher speeds, several of these technologies still lack improvements with regard to handoff performance. In this paper, we focus on wireless network technologies that rely on the Extensible Authentication Protocol for mutual authentication between the station and the access network. Such technologies include local area wireless networks (IEEE 802.11) as well as broadband wireless networks (IEEE 802.16). We present a new EAP authentication method based on a three party authentication scheme, namely Kerberos, that considerably shortens handoff delays. Compared to other methods, the proposed method has the advantage of not requiring any changes on the access points, making it readily deployable at reasonable costs.

Upper bound for energy efficiency in multi-cell fibre-wireless access systems

NARCIS (Netherlands)

Koonen, A.M.J.; Popov, M.; Wessing, H.

2013-01-01

Bringing radio access points closer to the end-users improves radio energy efficiency. However, taking into account both the radio and the optical parts of a fibre-wireless access system, the overall system energy efficiency has an upper bound determined by the relation between the energy

Upper bound for energy efficiency in multi-cell fibre-wireless access systems

DEFF Research Database (Denmark)

Koonen, A.M.J.; Popov, M.; Wessing, Henrik

2013-01-01

Bringing radio access points closer to the end-users improves radio energy efficiency. However, taking into account both the radio and the optical parts of a fibre-wireless access system, the overall system energy efficiency has an upper bound determined by the relation between the energy...

Cognitive radio networks medium access control for coexistence of wireless systems

CERN Document Server

Bian, Kaigui; Gao, Bo

2014-01-01

This book gives a comprehensive overview of the medium access control (MAC) principles in cognitive radio networks, with a specific focus on how such MAC principles enable different wireless systems to coexist in the same spectrum band and carry out spectrum sharing.  From algorithm design to the latest developments in the standards and spectrum policy, readers will benefit from leading-edge knowledge of how cognitive radio systems coexist and share spectrum resources.  Coverage includes cognitive radio rendezvous, spectrum sharing, channel allocation, coexistence in TV white space, and coexistence of heterogeneous wireless systems.   • Provides a comprehensive reference on medium access control (MAC)-related problems in the design of cognitive radio systems and networks; • Includes detailed analysis of various coexistence problems related to medium access control in cognitive radio networks; • Reveals novel techniques for addressing the challenges of coexistence protocol design at a higher level ...

Receiver-initiated medium access control protocols for wireless sensor networks

DEFF Research Database (Denmark)

Fafoutis, Xenofon; Di Mauro, Alessio; Vithanage, Madava D.

2015-01-01

One of the fundamental building blocks of a Wireless Sensor Network (WSN) is the Medium Access Control (MAC) protocol, that part of the system governing when and how two independent neighboring nodes activate their respective transceivers to directly interact. Historically, data exchange has always...

Temperature estimation of induction machines based on wireless sensor networks

Directory of Open Access Journals (Sweden)

Y. Huang

2018-04-01

Full Text Available In this paper, a fourth-order Kalman filter (KF algorithm is implemented in the wireless sensor node to estimate the temperatures of the stator winding, the rotor cage and the stator core in the induction machine. Three separate wireless sensor nodes are used as the data acquisition systems for different input signals. Six Hall sensors are used to acquire the three-phase stator currents and voltages of the induction machine. All of them are processed to root mean square (rms in ampere and volt. A rotary encoder is mounted for the rotor speed and Pt-1000 is used for the temperature of the coolant air. The processed signals in the physical unit are transmitted wirelessly to the host wireless sensor node, where the KF is implemented with fixed-point arithmetic in Contiki OS. Time-division multiple access (TDMA is used to make the wireless transmission more stable. Compared to the floating-point implementation, the fixed-point implementation has the same estimation accuracy at only about one-fifth of the computation time. The temperature estimation system can work under any work condition as long as there are currents through the machine. It can also be rebooted for estimation even when wireless transmission has collapsed or packages are missing.

A 15-meter Multi-Gigabit W-band Bidirectional Wireless Bridge in Fiber-Optic Access Networks

DEFF Research Database (Denmark)

Pang, Xiaodan; Vegas Olmos, Juan José; Lebedev, Alexander

2013-01-01

. The down-converted signal is re-modulated on to the lightwave and transmit further through the fiber-optic system. In the uplink, both up-and down-conversion are performed by electrical means. Furthermore, we investigate both passive and active wireless transmitters in this work for both downlink......We present a bidirectional wireless bridge in the W-band enabling the seamless convergence between the wireless and fiber-optic access networks. In the downlink, a 16 Gbit/s QPSK signal is photonically up-converted at the wireless transmitter and electrically down-converted at the wireless receiver...... and uplink transmissions. With an active wireless transmitter, up to 15 meters wireless transmission is successfully achieved with a BER below the 7% FEC limit in the downlink....

Digital predistortion of 75–110 GHz W-band frequency multiplier for fiber wireless short range access systems

DEFF Research Database (Denmark)

Zhao, Ying; Deng, Lei; Pang, Xiaodan

2011-01-01

be effectively pre-compensated. Without using costly W-band components, a transmission system with 26km fiber and 4m wireless transmission operating at 99.6GHz is experimentally validated. Adjacent-channel power ratio (ACPR) improvements for IQ-modulated vector signals are guaranteed and transmission......We present a W-band fiber-wireless transmission system based on a nonlinear frequency multiplier for high-speed wireless short range access applications. By implementing a baseband digital signal predistortion scheme, intensive nonlinear distortions induced in a sextuple frequency multiplier can...... performances for fiber and wireless channels are studied. This W-band predistortion technique is a promising candidate for applications in high capacity wireless-fiber access systems....

QoS Provisioning Techniques for Future Fiber-Wireless (FiWi Access Networks

Directory of Open Access Journals (Sweden)

Martin Maier

2010-04-01

Full Text Available A plethora of enabling optical and wireless access-metro network technologies have been emerging that can be used to build future-proof bimodal fiber-wireless (FiWi networks. Hybrid FiWi networks aim at providing wired and wireless quad-play services over the same infrastructure simultaneously and hold great promise to mitigate the digital divide and change the way we live and work by replacing commuting with teleworking. After overviewing enabling optical and wireless network technologies and their QoS provisioning techniques, we elaborate on enabling radio-over-fiber (RoF and radio-and-fiber (R&F technologies. We describe and investigate new QoS provisioning techniques for future FiWi networks, ranging from traffic class mapping, scheduling, and resource management to advanced aggregation techniques, congestion control, and layer-2 path selection algorithms.

Adaptive Media Access Control for Energy Harvesting - Wireless Sensor Networks

DEFF Research Database (Denmark)

Fafoutis, Xenofon; Dragoni, Nicola

2012-01-01

ODMAC (On-Demand Media Access Control) is a recently proposed MAC protocol designed to support individual duty cycles for Energy Harvesting — Wireless Sensor Networks (EH-WSNs). Individual duty cycles are vital for EH-WSNs, because they allow nodes to adapt their energy consumption to the ever-ch...

Propagation Characteristics in an Underground Shopping Area for 5GHz-band Wireless Access Systems

Science.gov (United States)

Itokawa, Kiyohiko; Kita, Naoki; Sato, Akio; Matsue, Hideaki; Mori, Daisuke; Watanabe, Hironobu

5-GHz band wireless access systems, such as the RLAN (Radio Local Area Network) system of IEEE802.11a, HiperLAN/2, HiSWANa and AWA, are developed and provide transmission rates over 20 Mbps for indoor use. Those 5-GHz access systems are expected to extend service areas from the office to the so-called “hot-spot" in public areas. Underground shopping malls are one of the anticipated service areas for such a nomadic wireless access service. Broadband propagation characteristics are required for radio zone design in an underground mall environment despite previous results obtained by narrow band measurements. This paper presents results of an experimental study on the propagation characteristics for broadband wireless access systems in an underground mall environment. First, broadband propagation path loss is measured and formulated considering human body shadowing. A ray trace simulation is used to clarify the basic propagation mechanism in such a closed environment. Next, a distance dependency of the delay spread during a crowded time period, rush hour, is found to be at most 65 nsec, which is under the permitted maximum value of the present 5-GHz systems. Finally, above propagation characteristics support the result of transmission test carried out by using AWA equipment.

Reconfigurable Radio Access Unit for DWDM to W-Band Wireless Conversion

DEFF Research Database (Denmark)

Chorchos, Łukasz; Rommel, Simon; Turkiewicz, Jarosław P.

2017-01-01

In this letter a reconfigurable Remote Access Unit (RAU) is proposed and demonstrated, interfacing dense wavelength division multiplexed (DWDM) optical and W-band wireless links. The RAU is composed of a tunable local oscillator, a narrow optical filter and a control unit, making it reconfigurable...

Wireless device monitoring methods, wireless device monitoring systems, and articles of manufacture

Science.gov (United States)

McCown, Steven H [Rigby, ID; Derr, Kurt W [Idaho Falls, ID; Rohde, Kenneth W [Idaho Falls, ID

2012-05-08

Wireless device monitoring methods, wireless device monitoring systems, and articles of manufacture are described. According to one embodiment, a wireless device monitoring method includes accessing device configuration information of a wireless device present at a secure area, wherein the device configuration information comprises information regarding a configuration of the wireless device, accessing stored information corresponding to the wireless device, wherein the stored information comprises information regarding the configuration of the wireless device, comparing the device configuration information with the stored information, and indicating the wireless device as one of authorized and unauthorized for presence at the secure area using the comparing.

Towards convergence of wireless and wireline signal transport in broadband access networks

DEFF Research Database (Denmark)

Yu, Xianbin; Prince, Kamau; Tafur Monroy, Idelfonso

2010-01-01

Hybrid optical wireless access networks are to play an important role in the realization of the vision of delivery of broadband services to the end-user any time, anywhere and at affordable costs. We present results of experiments conducted over a field deployed optical fibre links we successfull...... demonstrated converged wireless and wireline signal transport over a common fibre infrastructure. The type of signal used in this field deployed experiments cover WiMax, Impulse-radio ultra-wideband (UWB) and coherent transmission of baseband QPSK and radio-over-fibre signals....

Building secure wireless access point based on certificate authentication and firewall captive portal

Directory of Open Access Journals (Sweden)

Soewito B.

2014-03-01

Full Text Available Wireless local area network or WLAN more vulnerability than wired network even though WLAN has many advantages over wired. Wireless networks use radio transmissions to carry data between end users and access point. Therefore, it is possible for someone to sit in your office building's lobby or parking lot or parking lot to eavesdrop on the wireless network communication. This paper discussed securing wires local area network used WPA2 Enterprise based PEAP MS-CHAP and Captive portal firewall. We also divided the network for employer and visitor to increase the level of security. Our experiment showed that the WLAN could be broken using the attacker tool such as airodump, aireply, and aircrack.

The Effect of Information Access Strategy on Power Consumption and Reliability in Wireless Sensor Network

DEFF Research Database (Denmark)

Tobgay, Sonam; Olsen, Rasmus Løvenstein; Prasad, Ramjee

2013-01-01

This paper examines the effect of different information access strategies on power consumption and information reliability, considering the wireless sensor network as the source of information. Basically, the paper explores three different access strategies, namely; reactive, periodic and hybrid...

Polarization division multiple access with polarization modulation for LOS wireless communications

Directory of Open Access Journals (Sweden)

Cao Bin

2011-01-01

Full Text Available Abstract In this paper, we discuss a potential multiple access and modulation scheme based on polarized states (PS of electromagnetic (EM waves for line-of-sight (LOS communications. The proposed scheme is theoretic different from the existing polar modulation for EDGE and WCDMA systems. We propose the detailed bit representation (modulation and multiple access scheme using PS. Because of the inflexibility of polarization information in the time and frequency domains, as well as independence of frequency and space, the polarization information can be used independently for wireless communications, i.e., another independent resource domain that can be utilized. Due to the independence between the PS and the specific features of signals (such as waveform, bandwidth and data rate, the discussed polarization division multiple access (PDMA and polarization modulation (PM are expected to improve the spectrum utilization effectively. It is proved that the polarization filtering technique can be adopted in the PDMA-PM wireless communications to separate the multiuser signals and demodulate the bit information representing by PS for desired user. Some theoretical analysis is done to demonstrate the feasibility of the proposed scheme, and the simulation results are made to evaluate the performance of the suggested system.

Multiple wireless protocol advertising system, enabling automatic access selection and local services

NARCIS (Netherlands)

Houben, S.A.; Baken, N.; Herve, P.; Smets, R.

2006-01-01

We examined efficiency within wireless access options for mobile devices and discovered that a classic pitfall is revisited. As with the proliferation of services in incumbents’ portfolios, leading to a number of coexisting so-called ‘stove-pipes’, we see an isomorphic phenomenon evolving in

Incentive Mechanism for P2P Content Sharing over Heterogenous Access Networks

Science.gov (United States)

Sato, Kenichiro; Hashimoto, Ryo; Yoshino, Makoto; Shinkuma, Ryoichi; Takahashi, Tatsuro

In peer-to-peer (P2P) content sharing, users can share their content by contributing their own resources to one another. However, since there is no incentive for contributing contents or resources to others, users may attempt to obtain content without any contribution. To motivate users to contribute their resources to the service, incentive-rewarding mechanisms have been proposed. On the other hand, emerging wireless technologies, such as IEEE 802.11 wireless local area networks, beyond third generation (B3G) cellular networks and mobile WiMAX, provide high-speed Internet access for wireless users. Using these high-speed wireless access, wireless users can use P2P services and share their content with other wireless users and with fixed users. However, this diversification of access networks makes it difficult to appropriately assign rewards to each user according to their contributions. This is because the cost necessary for contribution is different in different access networks. In this paper, we propose a novel incentive-rewarding mechanism called EMOTIVER that can assign rewards to users appropriately. The proposed mechanism uses an external evaluator and interactive learning agents. We also investigate a way of appropriately controlling rewards based on the system service's quality and managing policy.

Combining Wired and Wireless Networks for a QoS-Aware Broadband Infrastructure

DEFF Research Database (Denmark)

Pedersen, Jens Myrup; Riaz, Muhammad Tahir; Knudsen, Thomas Phillip

2004-01-01

We show how integrated planning of wired and wireless infrastructures can be used to build a QoS-aware broadband infrastructure. The outset is a case study of the municipality of Hals, a rural community in Denmark, where the objective is to establish a broadband infrastructure reaching all househ...... To The Home for primary connections and Fixed Wireless Access for backup. This is implemented over 15 years, during which temporary solutions ensure sufficient QoS and reliability for all users. These temporary solutions form parts of the final solutions....

An Adaptive Channel Access Method for Dynamic Super Dense Wireless Sensor Networks.

Science.gov (United States)

Lei, Chunyang; Bie, Hongxia; Fang, Gengfa; Zhang, Xuekun

2015-12-03

Super dense and distributed wireless sensor networks have become very popular with the development of small cell technology, Internet of Things (IoT), Machine-to-Machine (M2M) communications, Vehicular-to-Vehicular (V2V) communications and public safety networks. While densely deployed wireless networks provide one of the most important and sustainable solutions to improve the accuracy of sensing and spectral efficiency, a new channel access scheme needs to be designed to solve the channel congestion problem introduced by the high dynamics of competing nodes accessing the channel simultaneously. In this paper, we firstly analyzed the channel contention problem using a novel normalized channel contention analysis model which provides information on how to tune the contention window according to the state of channel contention. We then proposed an adaptive channel contention window tuning algorithm in which the contention window tuning rate is set dynamically based on the estimated channel contention level. Simulation results show that our proposed adaptive channel access algorithm based on fast contention window tuning can achieve more than 95 % of the theoretical optimal throughput and 0 . 97 of fairness index especially in dynamic and dense networks.

An Adaptive Channel Access Method for Dynamic Super Dense Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Chunyang Lei

2015-12-01

Full Text Available Super dense and distributed wireless sensor networks have become very popular with the development of small cell technology, Internet of Things (IoT, Machine-to-Machine (M2M communications, Vehicular-to-Vehicular (V2V communications and public safety networks. While densely deployed wireless networks provide one of the most important and sustainable solutions to improve the accuracy of sensing and spectral efficiency, a new channel access scheme needs to be designed to solve the channel congestion problem introduced by the high dynamics of competing nodes accessing the channel simultaneously. In this paper, we firstly analyzed the channel contention problem using a novel normalized channel contention analysis model which provides information on how to tune the contention window according to the state of channel contention. We then proposed an adaptive channel contention window tuning algorithm in which the contention window tuning rate is set dynamically based on the estimated channel contention level. Simulation results show that our proposed adaptive channel access algorithm based on fast contention window tuning can achieve more than 95 % of the theoretical optimal throughput and 0 . 97 of fairness index especially in dynamic and dense networks.

Convergent optical wired and wireless long-reach access network using high spectral-efficient modulation.

Science.gov (United States)

Chow, C W; Lin, Y H

2012-04-09

To provide broadband services in a single and low cost perform, the convergent optical wired and wireless access network is promising. Here, we propose and demonstrate a convergent optical wired and wireless long-reach access networks based on orthogonal wavelength division multiplexing (WDM). Both the baseband signal and the radio-over-fiber (ROF) signal are multiplexed and de-multiplexed in optical domain, hence it is simple and the operation speed is not limited by the electronic bottleneck caused by the digital signal processing (DSP). Error-free de-multiplexing and down-conversion can be achieved for all the signals after 60 km (long-reach) fiber transmission. The scalability of the system for higher bit-rate (60 GHz) is also simulated and discussed.

Multilayer Statistical Intrusion Detection in Wireless Networks

Science.gov (United States)

Hamdi, Mohamed; Meddeb-Makhlouf, Amel; Boudriga, Noureddine

2008-12-01

The rapid proliferation of mobile applications and services has introduced new vulnerabilities that do not exist in fixed wired networks. Traditional security mechanisms, such as access control and encryption, turn out to be inefficient in modern wireless networks. Given the shortcomings of the protection mechanisms, an important research focuses in intrusion detection systems (IDSs). This paper proposes a multilayer statistical intrusion detection framework for wireless networks. The architecture is adequate to wireless networks because the underlying detection models rely on radio parameters and traffic models. Accurate correlation between radio and traffic anomalies allows enhancing the efficiency of the IDS. A radio signal fingerprinting technique based on the maximal overlap discrete wavelet transform (MODWT) is developed. Moreover, a geometric clustering algorithm is presented. Depending on the characteristics of the fingerprinting technique, the clustering algorithm permits to control the false positive and false negative rates. Finally, simulation experiments have been carried out to validate the proposed IDS.

Performance Evaluation of TDMA Medium Access Control Protocol in Cognitive Wireless Networks

Directory of Open Access Journals (Sweden)

Muhammed Enes Bayrakdar

2017-02-01

Full Text Available Cognitive radio paradigm has been revealed as a new communication technology that shares channels in wireless networks. Channel assignment is a crucial issue in the field of cognitive wireless networks because of the spectrum scarcity. In this work, we have evaluated the performance of TDMA medium access control protocol. In our simulation scenarios, primary users and secondary users utilize TDMA as a medium access control protocol. We have designed a network environment in Riverbed simulation software that consists of primary users, secondary users, and base stations. In our system model, secondary users sense the spectrum and inform the base station about empty channels. Then, the base station decides accordingly which secondary user may utilize the empty channel. Energy detection technique is employed as a spectrum sensing technique because it is the best when information about signal of primary user is acquired. Besides, different number of users is selected in simulation scenarios in order to obtain accurate delay and throughput results. Comparing analytical model with simulation results, we have shown that performance analysis of our system model is consistent and accurate.

Secure and Efficient Access Control Scheme for Wireless Sensor Networks in the Cross-Domain Context of the IoT

Directory of Open Access Journals (Sweden)

Ming Luo

2018-01-01

Full Text Available Nowadays wireless sensor network (WSN is increasingly being used in the Internet of Things (IoT for data collection, and design of an access control scheme that allows an Internet user as part of IoT to access the WSN becomes a hot topic. A lot of access control schemes have been proposed for the WSNs in the context of the IoT. Nevertheless, almost all of these schemes assume that communication nodes in different network domains share common system parameters, which is not suitable for cross-domain IoT environment in practical situations. To solve this shortcoming, we propose a more secure and efficient access control scheme for wireless sensor networks in the cross-domain context of the Internet of Things, which allows an Internet user in a certificateless cryptography (CLC environment to communicate with a sensor node in an identity-based cryptography (IBC environment with different system parameters. Moreover, our proposed scheme achieves known session-specific temporary information security (KSSTIS that most of access control schemes cannot satisfy. Performance analysis is given to show that our scheme is well suited for wireless sensor networks in the cross-domain context of the IoT.

QoS Modeling for End-to-End Performance Evaluation over Networks with Wireless Access

Directory of Open Access Journals (Sweden)

Gómez Gerardo

2010-01-01

Full Text Available This paper presents an end-to-end Quality of Service (QoS model for assessing the performance of data services over networks with wireless access. The proposed model deals with performance degradation across protocol layers using a bottom-up strategy, starting with the physical layer and moving on up to the application layer. This approach makes it possible to analytically assess performance at different layers, thereby facilitating a possible end-to-end optimization process. As a representative case, a scenario where a set of mobile terminals connected to a streaming server through an IP access node has been studied. UDP, TCP, and the new TCP-Friendly Rate Control (TFRC protocols were analyzed at the transport layer. The radio interface consisted of a variable-rate multiuser and multichannel subsystem, including retransmissions and adaptive modulation and coding. The proposed analytical QoS model was validated on a real-time emulator of an end-to-end network with wireless access and proved to be very useful for the purposes of service performance estimation and optimization.

Virus spreading in wireless sensor networks with a medium access control mechanism

International Nuclear Information System (INIS)

Wang Ya-Qi; Yang Xiao-Yuan

2013-01-01

In this paper, an extended version of standard susceptible-infected (SI) model is proposed to consider the influence of a medium access control mechanism on virus spreading in wireless sensor networks. Theoretical analysis shows that the medium access control mechanism obviously reduces the density of infected nodes in the networks, which has been ignored in previous studies. It is also found that by increasing the network node density or node communication radius greatly increases the number of infected nodes. The theoretical results are confirmed by numerical simulations. (general)

One4All Cooperative Media Access Strategy in Infrastructure Based Distributed Wireless Networks

DEFF Research Database (Denmark)

Zhang, Qi; Fitzek, Frank H.P.; Iversen, Villy Bæk

2008-01-01

a cooperative cluster using their short-range air interface and one device contends the channel for all the devices within the cluster. This strategy reduces the number of mobile devices involved in the collision process for the wireless medium resulting in larger throughput, smaller access delay, and less...

Compact printed multiband antenna with independent setting suitable for fixed and reconfigurable wireless communication systems

KAUST Repository

Abutarboush, Hattan

2012-08-01

This paper presents the design of a low-profile compact printed antenna for fixed frequency and reconfigurable frequency bands. The antenna consists of a main patch, four sub-patches, and a ground plane to generate five frequency bands, at 0.92, 1.73, 1.98, 2.4, and 2.9 GHz, for different wireless systems. For the fixed-frequency design, the five individual frequency bands can be adjusted and set independently over the wide ranges of 18.78%, 22.75%, 4.51%, 11%, and 8.21%, respectively, using just one parameter of the antenna. By putting a varactor (diode) at each of the sub-patch inputs, four of the frequency bands can be controlled independently over wide ranges and the antenna has a reconfigurable design. The tunability ranges for the four bands of 0.92, 1.73, 1.98, and 2.9 GHz are 23.5%, 10.30%, 13.5%, and 3%, respectively. The fixed and reconfigurable designs are studied using computer simulation. For verification of simulation results, the two designs are fabricated and the prototypes are measured. The results show a good agreement between simulated and measured results. © 1963-2012 IEEE.

Compact printed multiband antenna with independent setting suitable for fixed and reconfigurable wireless communication systems

KAUST Repository

Abutarboush, Hattan; Nilavalan, Rajagopal; Cheung, Sing Wai; Nasr, Karim Medhat A

2012-01-01

This paper presents the design of a low-profile compact printed antenna for fixed frequency and reconfigurable frequency bands. The antenna consists of a main patch, four sub-patches, and a ground plane to generate five frequency bands, at 0.92, 1.73, 1.98, 2.4, and 2.9 GHz, for different wireless systems. For the fixed-frequency design, the five individual frequency bands can be adjusted and set independently over the wide ranges of 18.78%, 22.75%, 4.51%, 11%, and 8.21%, respectively, using just one parameter of the antenna. By putting a varactor (diode) at each of the sub-patch inputs, four of the frequency bands can be controlled independently over wide ranges and the antenna has a reconfigurable design. The tunability ranges for the four bands of 0.92, 1.73, 1.98, and 2.9 GHz are 23.5%, 10.30%, 13.5%, and 3%, respectively. The fixed and reconfigurable designs are studied using computer simulation. For verification of simulation results, the two designs are fabricated and the prototypes are measured. The results show a good agreement between simulated and measured results. © 1963-2012 IEEE.

Wireless Technology in K-12 Education

Science.gov (United States)

Walery, Darrell

2004-01-01

Many schools begin implementing wireless technology slowly by creating wireless "hotspots" on the fly. This is accomplished by putting a wireless access point on a cart along with a set of wireless laptop computers. A teacher can then wheel the cart anywhere in the school that has a network drop, plug the access point in and have an…

A scalable and continuous-upgradable optical wireless and wired convergent access network.

Science.gov (United States)

Sung, J Y; Cheng, K T; Chow, C W; Yeh, C H; Pan, C-L

2014-06-02

In this work, a scalable and continuous upgradable convergent optical access network is proposed. By using a multi-wavelength coherent comb source and a programmable waveshaper at the central office (CO), optical millimeter-wave (mm-wave) signals of different frequencies (from baseband to > 100 GHz) can be generated. Hence, it provides a scalable and continuous upgradable solution for end-user who needs 60 GHz wireless services now and > 100 GHz wireless services in the future. During the upgrade, user only needs to upgrade their optical networking unit (ONU). A programmable waveshaper is used to select the suitable optical tones with wavelength separation equals to the desired mm-wave frequency; while the CO remains intact. The centralized characteristics of the proposed system can easily add any new service and end-user. The centralized control of the wavelength makes the system more stable. Wired data rate of 17.45 Gb/s and w-band wireless data rate up to 3.36 Gb/s were demonstrated after transmission over 40 km of single-mode fiber (SMF).

Accessing Wireless Sensor Networks Via Dynamically Reconfigurable Interaction Models

Directory of Open Access Journals (Sweden)

Maria Cecília Gomes

2012-12-01

Full Text Available The Wireless Sensor Networks (WSNs technology is already perceived as fundamental for science across many domains, since it provides a low cost solution for environment monitoring. WSNs representation via the service concept and its inclusion in Web environments, e.g. through Web services, supports particularly their open/standard access and integration. Although such Web enabled WSNs simplify data access, network parameterization and aggregation, the existing interaction models and run-time adaptation mechanisms available to clients are still scarce. Nevertheless, applications increasingly demand richer and more flexible accesses besides the traditional client/server. For instance, applications may require a streaming model in order to avoid sequential data requests, or the asynchronous notification of subscribed data through the publish/subscriber. Moreover, the possibility to automatically switch between such models at runtime allows applications to define flexible context-based data acquisition. To this extent, this paper discusses the relevance of the session and pattern abstractions on the design of a middleware prototype providing richer and dynamically reconfigurable interaction models to Web enabled WSNs.

The challenges of M2M massive access in wireless cellular networks

Directory of Open Access Journals (Sweden)

Andrea Biral

2015-02-01

Full Text Available The next generation of communication systems, which is commonly referred to as 5G, is expected to support, besides the traditional voice and data services, new communication paradigms, such as Internet of Things (IoT and Machine-to-Machine (M2M services, which involve communication between Machine-Type Devices (MTDs in a fully automated fashion, thus, without or with minimal human intervention. Although the general requirements of 5G systems are progressively taking shape, the technological issues raised by such a vision are still partially unclear. Nonetheless, general consensus has been reached upon some specific challenges, such as the need for 5G wireless access networks to support massive access by MTDs, as a consequence of the proliferation of M2M services. In this paper, we describe the main challenges raised by the M2M vision, focusing in particular on the problems related to the support of massive MTD access in current cellular communication systems. Then we analyze the most common approaches proposed in the literature to enable the coexistence of conventional and M2M services in the current and next generation of cellular wireless systems. We finally conclude by pointing out the research challenges that require further investigation in order to provide full support to the M2M paradigm.

EEM{sup TM} wireless supervision

Energy Technology Data Exchange (ETDEWEB)

Bilic, H. [Ericsson-Nikola Tesla d.d. Zagreb (Croatia)

2000-07-01

By adding the GSM network to the communication level of Energy Management systems, energy operating centres (EOC) can offer wireless access to the supervised equipment. Furthermore EOC can profit from rapid service development in the GSM networks. With implementation of GPRS to the GSM network EOC can instantly offer wireless access to external IP based networks such as Internet and corporate Intranets. The author describes architecture and key characteristic of Ericsson EnergyMaster{sup TM} (EEM{sup TM}) system for Energy Management, how and where to implement wireless supervision, wireless access to IP addresses and also how to implement new services provided by the GSM network. (orig.)

A hybrid medium access control for convergence of broadband wireless and wireline ATM networks

DEFF Research Database (Denmark)

Liu, Hong; Gliese, Ulrik Bo; Dittmann, Lars

2000-01-01

In this paper, we propose a hybrid medium access control protocol for supporting broadband integrated services in the wireless ATM networks. The integrated services include CBR, VBR and ABR traffic varying from low bit-rate to very high bit-rate. The proposed protocol is an excellent compromise...

Wireless virtualization

CERN Document Server

Wen, Heming; Le-Ngoc, Tho

2013-01-01

This SpringerBriefs is an overview of the emerging field of wireless access and mobile network virtualization. It provides a clear and relevant picture of the current virtualization trends in wireless technologies by summarizing and comparing different architectures, techniques and technologies applicable to a future virtualized wireless network infrastructure. The readers are exposed to a short walkthrough of the future Internet initiative and network virtualization technologies in order to understand the potential role of wireless virtualization in the broader context of next-generation ubiq

Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

OpenAIRE

Razaque, Abdul; Elleithy, Khaled M.

2014-01-01

This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC) for wireless sensor networks (WSNs), which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols,...

Design Aspects of An Energy-Efficient, Lightweight Medium Access Control Protocol for Wireless Sensor Networks

NARCIS (Netherlands)

van Hoesel, L.F.W.; Havinga, Paul J.M.

2006-01-01

This document gives an overview of the most relevant design aspects of the lightweight medium access control (LMAC) protocol [16] for wireless sensor networks (WSNs). These aspects include selfconfiguring and localized operation of the protocol, time synchronization in multi-hop networks, network

A Fine-Grained Data Access Control System in Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Boniface K. Alese

2015-12-01

Full Text Available The evolving realities of Wireless Sensor Network (WSN deployed to various terrain of life require serving multiple applications. As large amount of sensed data are distributed and stored in individual sensors nodes, the illegal access to these sensitive data can be devastating. Consequently, data insecurity becomes a big concern. This study, therefore, proposes a fine-grained access control system which only requires the right set of users to access a particular data, based on their access privileges in the sensor networks. It is designed using Priccess Protocol with Access policy formulation adopting the principle of Bell Lapadula model as well as Attribute-Based Encryption (ABE to control access to sensor data. The functionality of the proposed system is simulated using Netbeans. The performance analysis of the proposed system using execution time and size of the key show that the higher the key size, the harder it becomes for the attacker to hack the system. Additionally, the time taken for the proposed work is lesser which makes the work faster than the existing work. Consequently, a well secure interactive web-based application that could facilitates the field officers access to stored data in safe and secure manner is developed.

Rogue AP Detection in the Wireless LAN for Large Scale Deployment

Directory of Open Access Journals (Sweden)

Sang-Eon Kim

2006-10-01

Full Text Available The wireless LAN standard, also known as WiFi, has begun to use commercial purposes. This paper describes access network architecture of wireless LAN for large scale deployment to provide public service. A metro Ethernet and digital subscriber line access network can be used for wireless LAN with access point. In this network architecture, access point plays interface between wireless node and network infrastructure. It is important to maintain access point without any failure and problems to public users. This paper proposes definition of rogue access point and classifies based on functional problem to access the Internet. After that, rogue access point detection scheme is described based on classification over the wireless LAN. The rogue access point detector can greatly improve the network availability to network service provider of wireless LAN.

Channel capacity of TDD-OFDM-MIMO for multiple access points in a wireless single-frequency-network

DEFF Research Database (Denmark)

Takatori, Y.; Fitzek, Frank; Tsunekawa, K.

2005-01-01

MIMO data transmission scheme, which combines Single-Frequency-Network (SFN) with TDD-OFDM-MIMO applied for wireless LAN networks. In our proposal, we advocate to use SFN for multiple access points (MAP) MIMO data transmission. The goal of this approach is to achieve very high channel capacity in both......The multiple-input-multiple-output (MIMO) technique is the most attractive candidate to improve the spectrum efficiency in the next generation wireless communication systems. However, the efficiency of MIMO techniques reduces in the line of sight (LOS) environments. In this paper, we propose a new...

Access Selection Algorithm of Heterogeneous Wireless Networks for Smart Distribution Grid Based on Entropy-Weight and Rough Set

Science.gov (United States)

Xiang, Min; Qu, Qinqin; Chen, Cheng; Tian, Li; Zeng, Lingkang

2017-11-01

To improve the reliability of communication service in smart distribution grid (SDG), an access selection algorithm based on dynamic network status and different service types for heterogeneous wireless networks was proposed. The network performance index values were obtained in real time by multimode terminal and the variation trend of index values was analyzed by the growth matrix. The index weights were calculated by entropy-weight and then modified by rough set to get the final weights. Combining the grey relational analysis to sort the candidate networks, and the optimum communication network is selected. Simulation results show that the proposed algorithm can implement dynamically access selection in heterogeneous wireless networks of SDG effectively and reduce the network blocking probability.

Proposal of Wireless Traffic Control Schemes for Wireless LANs

Science.gov (United States)

Hiraguri, Takefumi; Ichikawa, Takeo; Iizuka, Masataka; Kubota, Shuji

This paper proposes two traffic control schemes to support the communication quality of multimedia streaming services such as VoIP and audio/video over IEEE 802.11 wireless LAN systems. The main features of the proposed scheme are bandwidth control for each flow of the multimedia streaming service and load balancing between access points (APs) of the wireless LAN by using information of data link, network and transport layers. The proposed schemes are implemented on a Linux machine which is called the wireless traffic controller (WTC). The WTC connects a high capacity backbone network and an access network to which the APs are attached. We evaluated the performance of the proposed WTC and confirmed that the communication quality of the multimedia streaming would be greatly improved by using this technique.

A novel PON based UMTS broadband wireless access network architecture with an algorithm to guarantee end to end QoS

Science.gov (United States)

Sana, Ajaz; Hussain, Shahab; Ali, Mohammed A.; Ahmed, Samir

2007-09-01

In this paper we proposes a novel Passive Optical Network (PON) based broadband wireless access network architecture to provide multimedia services (video telephony, video streaming, mobile TV, mobile emails etc) to mobile users. In the conventional wireless access networks, the base stations (Node B) and Radio Network Controllers (RNC) are connected by point to point T1/E1 lines (Iub interface). The T1/E1 lines are expensive and add up to operating costs. Also the resources (transceivers and T1/E1) are designed for peak hours traffic, so most of the time the dedicated resources are idle and wasted. Further more the T1/E1 lines are not capable of supporting bandwidth (BW) required by next generation wireless multimedia services proposed by High Speed Packet Access (HSPA, Rel.5) for Universal Mobile Telecommunications System (UMTS) and Evolution Data only (EV-DO) for Code Division Multiple Access 2000 (CDMA2000). The proposed PON based back haul can provide Giga bit data rates and Iub interface can be dynamically shared by Node Bs. The BW is dynamically allocated and the unused BW from lightly loaded Node Bs is assigned to heavily loaded Node Bs. We also propose a novel algorithm to provide end to end Quality of Service (QoS) (between RNC and user equipment).The algorithm provides QoS bounds in the wired domain as well as in wireless domain with compensation for wireless link errors. Because of the air interface there can be certain times when the user equipment (UE) is unable to communicate with Node B (usually referred to as link error). Since the link errors are bursty and location dependent. For a proposed approach, the scheduler at the Node B maps priorities and weights for QoS into wireless MAC. The compensations for errored links is provided by the swapping of services between the active users and the user data is divided into flows, with flows allowed to lag or lead. The algorithm guarantees (1)delay and throughput for error-free flows,(2)short term fairness

Architectural Considerations of Fiber-Radio Millimeter-Wave Wireless Access Systems

Science.gov (United States)

Kitayama, Ken-Ichi

The architecture of fiber-radio mm-wave wireless access systems critically depends upon the optical mm-wave generation and transport techniques. Four optical mm-wave generation and transport techniques: 1) optical self-heterodyning, 2) external modulation, 3) up- and downconversion, and 4) optical transceiver, will be assessed. From the technical viewpoints, their advantages and disadvantages are discussed. The economical assessment, focusing on the cost of a base station BS ( ), will suggest that the optical transceiver looks the most promising in the long run, but in the near future, however, the external modulation will be cost-effective. The experimental results of 60 GHz testbeds using the external modulation will support the conclusion.

Rogue AP Detection in the Wireless LAN for Large Scale Deployment

OpenAIRE

Sang-Eon Kim; Byung-Soo Chang; Sang Hong Lee; Dae Young Kim

2006-01-01

The wireless LAN standard, also known as WiFi, has begun to use commercial purposes. This paper describes access network architecture of wireless LAN for large scale deployment to provide public service. A metro Ethernet and digital subscriber line access network can be used for wireless LAN with access point. In this network architecture, access point plays interface between wireless node and network infrastructure. It is important to maintain access point without any failure and problems to...

Efficient Design of OFDMA-Based Programmable Wireless Radios

Directory of Open Access Journals (Sweden)

Shah SFA

2008-01-01

Full Text Available With the increasing demand for efficient spectrum management, programmable wireless radios can potentially play a key role in shaping our future spectrum use. In this paper, we consider the design of low-power programmable wireless radios based on orthogonal frequency division multiple access (OFDMA. To meet the demands of higher data rate communications, we split OFDMA symbols carrying multiuser data across several noncontiguous bands of available spectrum. To relax power consumption in analog-to-digital and digital-to-analog converters, we use a programmable narrowband RF front end comprising of programmable synthesizers and fixed low-pass filters. To perform digital baseband signal processing in an energy efficient manner, we propose efficient designs for the fast Fourier transform (FFT and inverse FFT (IFFT modules. Our designs of the FFT/IFFT modules reduce power consumption and chip area, and are capable of handling the dynamic nature of spectrum in programmable radios. To recover data that falls within the transition band of the filters, we propose a combiner similar to maximal ratio combiner. We also present the complete design of programmable wireless radios in accordance with the IEEE 802.22 (draft standard.

Efficient Design of OFDMA-Based Programmable Wireless Radios

Directory of Open Access Journals (Sweden)

A. H. Tewfik

2008-03-01

Full Text Available With the increasing demand for efficient spectrum management, programmable wireless radios can potentially play a key role in shaping our future spectrum use. In this paper, we consider the design of low-power programmable wireless radios based on orthogonal frequency division multiple access (OFDMA. To meet the demands of higher data rate communications, we split OFDMA symbols carrying multiuser data across several noncontiguous bands of available spectrum. To relax power consumption in analog-to-digital and digital-to-analog converters, we use a programmable narrowband RF front end comprising of programmable synthesizers and fixed low-pass filters. To perform digital baseband signal processing in an energy efficient manner, we propose efficient designs for the fast Fourier transform (FFT and inverse FFT (IFFT modules. Our designs of the FFT/IFFT modules reduce power consumption and chip area, and are capable of handling the dynamic nature of spectrum in programmable radios. To recover data that falls within the transition band of the filters, we propose a combiner similar to maximal ratio combiner. We also present the complete design of programmable wireless radios in accordance with the IEEE 802.22 (draft standard.

Wireless Positioning Based on a Segment-Wise Linear Approach for Modeling the Target Trajectory

DEFF Research Database (Denmark)

Figueiras, Joao; Pedersen, Troels; Schwefel, Hans-Peter

2008-01-01

Positioning solutions in infrastructure-based wireless networks generally operate by exploiting the channel information of the links between the Wireless Devices and fixed networking Access Points. The major challenge of such solutions is the modeling of both the noise properties of the channel...... measurements and the user mobility patterns. One class of typical human being movement patterns is the segment-wise linear approach, which is studied in this paper. Current tracking solutions, such as the Constant Velocity model, hardly handle such segment-wise linear patterns. In this paper we propose...... a segment-wise linear model, called the Drifting Points model. The model results in an increased performance when compared with traditional solutions....

VLSI Implementation of a Fixed-Complexity Soft-Output MIMO Detector for High-Speed Wireless

Directory of Open Access Journals (Sweden)

Di Wu

2010-01-01

Full Text Available This paper presents a low-complexity MIMO symbol detector with close-Maximum a posteriori performance for the emerging multiantenna enhanced high-speed wireless communications. The VLSI implementation is based on a novel MIMO detection algorithm called Modified Fixed-Complexity Soft-Output (MFCSO detection, which achieves a good trade-off between performance and implementation cost compared to the referenced prior art. By including a microcode-controlled channel preprocessing unit and a pipelined detection unit, it is flexible enough to cover several different standards and transmission schemes. The flexibility allows adaptive detection to minimize power consumption without degradation in throughput. The VLSI implementation of the detector is presented to show that real-time MIMO symbol detection of 20 MHz bandwidth 3GPP LTE and 10 MHz WiMAX downlink physical channel is achievable at reasonable silicon cost.

The Lure of Wireless Encryption

CERN Multimedia

Computer Security Team

2013-01-01

Following our article entitled “Jekyll or Hyde? Better browse securely” in the last issue of the Bulletin, some people wondered why the CERN wireless network is not encrypted…   There are many arguments why it is not. The simplest is usability: the communication and management of the corresponding access keys would be challenging given the sheer number of wireless devices the CERN network hosts. Keys would quickly become public, e.g. at conferences, and might be shared, written on whiteboards, etc. Then there are all the devices which cannot be easily configured to use encryption protocols - a fact which would create plenty of calls to the CERN Service Desk… But our main argument is that wireless encryption is DECEPTIVE. Wireless encryption is deceptive as it only protects the wireless network against unauthorised access (and the CERN network already has other means to protect against that). Wireless encryption however, does not really help you. You ...

Getting ahead of the curve in wireless communications | CRDI ...

International Development Research Centre (IDRC) Digital Library (Canada)

The demand for wireless communications is expected to increase significantly over ... would become more accessible to those without mobile phones, or Internet access. ... that will have a lasting impact on the field of wireless communications. ... problems: cooperative communication, coexistence of wireless systems, and ...

Security for multihop wireless networks

CERN Document Server

Khan, Shafiullah

2014-01-01

Security for Multihop Wireless Networks provides broad coverage of the security issues facing multihop wireless networks. Presenting the work of a different group of expert contributors in each chapter, it explores security in mobile ad hoc networks, wireless sensor networks, wireless mesh networks, and personal area networks.Detailing technologies and processes that can help you secure your wireless networks, the book covers cryptographic coprocessors, encryption, authentication, key management, attacks and countermeasures, secure routing, secure medium access control, intrusion detection, ep

A novel and efficient user access control scheme for wireless body area sensor networks

Directory of Open Access Journals (Sweden)

Santanu Chatterjee

2014-07-01

Full Text Available Wireless body area networks (WBANs can be applied to provide healthcare and patient monitoring. However, patient privacy can be vulnerable in a WBAN unless security is considered. Access to authorized users for the correct information and resources for different services can be provided with the help of efficient user access control mechanisms. This paper proposes a new user access control scheme for a WBAN. The proposed scheme makes use of a group-based user access ID, an access privilege mask, and a password. An elliptic curve cryptography-based public key cryptosystem is used to ensure that a particular legitimate user can only access the information for which he/she is authorized. We show that our scheme performs better than previously existing user access control schemes. Through a security analysis, we show that our scheme is secure against possible known attacks. Furthermore, through a formal security verification using the AVISPA (Automated Validation of Internet Security Protocols and Applications tool, we show that our scheme is also secure against passive and active attacks.

Wireless sensor networks architectures and protocols

CERN Document Server

Callaway, Jr, Edgar H

2003-01-01

Introduction to Wireless Sensor NetworksApplications and MotivationNetwork Performance ObjectivesContributions of this BookOrganization of this BookThe Development of Wireless Sensor NetworksEarly Wireless NetworksWireless Data NetworksWireless Sensor and Related NetworksConclusionThe Physical LayerSome Physical Layer ExamplesA Practical Physical Layer for Wireless Sensor NetworksSimulations and ResultsConclusionThe Data Link LayerMedium Access Control TechniquesThe Mediation DeviceSystem Analysis and SimulationConclusionThe Network LayerSome Network Design ExamplesA Wireless Sensor Network De

Wireless telecommunication systems

CERN Document Server

Terré, Michel; Vivier, Emmanuelle

2013-01-01

Wireless telecommunication systems generate a huge amount of interest. In the last two decades, these systems have experienced at least three major technological leaps, and it has become impossible to imagine how society was organized without them. In this book, we propose a macroscopic approach on wireless systems, and aim at answering key questions about power, data rates, multiple access, cellular engineering and access networks architectures.We present a series of solved problems, whose objective is to establish the main elements of a global link budget in several radiocommunicati

802.11 Wireless Networks The Definitive Guide

CERN Document Server

Gast, Matthew S

2005-01-01

As we all know by now, wireless networks offer many advantages over fixed (or wired) networks. Foremost on that list is mobility, since going wireless frees you from the tether of an Ethernet cable at a desk. But that's just the tip of the cable-free iceberg. Wireless networks are also more flexible, faster and easier for you to use, and more affordable to deploy and maintain. The de facto standard for wireless networking is the 802.11 protocol, which includes Wi-Fi (the wireless standard known as 802.11b) and its faster cousin, 802.11g. With easy-to-install 802.11 network hardware avail

Efficient scheduling request algorithm for opportunistic wireless access

KAUST Repository

Nam, Haewoon

2011-08-01

An efficient scheduling request algorithm for opportunistic wireless access based on user grouping is proposed in this paper. Similar to the well-known opportunistic splitting algorithm, the proposed algorithm initially adjusts (or lowers) the threshold during a guard period if no user sends a scheduling request. However, if multiple users make requests simultaneously and therefore a collision occurs, the proposed algorithm no longer updates the threshold but narrows down the user search space by splitting the users into multiple groups iteratively, whereas the opportunistic splitting algorithm keeps adjusting the threshold until a single user is found. Since the threshold is only updated when no user sends a request, it is shown that the proposed algorithm significantly alleviates the burden of the signaling for the threshold distribution to the users by the scheduler. More importantly, the proposed algorithm requires a less number of mini-slots to make a user selection given a certain scheduling outage probability. © 2011 IEEE.

Capacity Analysis of Wireless Mesh Networks

Directory of Open Access Journals (Sweden)

M. I. Gumel

2012-06-01

Full Text Available The next generation wireless networks experienced a great development with emergence of wireless mesh networks (WMNs, which can be regarded as a realistic solution that provides wireless broadband access. The limited available bandwidth makes capacity analysis of the network very essential. While the network offers broadband wireless access to community and enterprise users, the problems that limit the network capacity must be addressed to exploit the optimum network performance. The wireless mesh network capacity analysis shows that the throughput of each mesh node degrades in order of l/n with increasing number of nodes (n in a linear topology. The degradation is found to be higher in a fully mesh network as a result of increase in interference and MAC layer contention in the network.

A Lightweight Medium Access Protocol (LMAC) for Wireless Sensor Networks: Reducing Preamble Transmissions and Transceiver State Switches

NARCIS (Netherlands)

van Hoesel, L.F.W.; Havinga, Paul J.M.

2004-01-01

In this paper, we present an energy-efficient medium access protocol designed for wireless sensor networks. Although the protocol uses TDMA to give nodes in the WSN the opportunity to communicate collision-free, the network is self-organizing in terms of time slot assignment and synchronization. The

Data converters for wireless standards

CERN Document Server

Shi, Chunlei

2002-01-01

Wireless communication is witnessing tremendous growth with proliferation of different standards covering wide, local and personal area networks (WAN, LAN and PAN). The trends call for designs that allow 1) smooth migration to future generations of wireless standards with higher data rates for multimedia applications, 2) convergence of wireless services allowing access to different standards from the same wireless device, 3) inter-continental roaming. This requires designs that work across multiple wireless standards, can easily be reused, achieve maximum hardware share at a minimum power consumption levels particularly for mobile battery-operated devices.

Provably Secure Heterogeneous Access Control Scheme for Wireless Body Area Network.

Science.gov (United States)

Omala, Anyembe Andrew; Mbandu, Angolo Shem; Mutiria, Kamenyi Domenic; Jin, Chunhua; Li, Fagen

2018-04-28

Wireless body area network (WBAN) provides a medium through which physiological information could be harvested and transmitted to application provider (AP) in real time. Integrating WBAN in a heterogeneous Internet of Things (IoT) ecosystem would enable an AP to monitor patients from anywhere and at anytime. However, the IoT roadmap of interconnected 'Things' is still faced with many challenges. One of the challenges in healthcare is security and privacy of streamed medical data from heterogeneously networked devices. In this paper, we first propose a heterogeneous signcryption scheme where a sender is in a certificateless cryptographic (CLC) environment while a receiver is in identity-based cryptographic (IBC) environment. We then use this scheme to design a heterogeneous access control protocol. Formal security proof for indistinguishability against adaptive chosen ciphertext attack and unforgeability against adaptive chosen message attack in random oracle model is presented. In comparison with some of the existing access control schemes, our scheme has lower computation and communication cost.

Power Stabilization Strategy of Random Access Loads in Electric Vehicles Wireless Charging System at Traffic Lights

Directory of Open Access Journals (Sweden)

Linlin Tan

2016-10-01

Full Text Available An opportunity wireless charging system for electric vehicles when they stop and wait at traffic lights is proposed in this paper. In order to solve the serious power fluctuation caused by random access loads, this study presents a power stabilization strategy based on counting the number of electric vehicles in a designated area, including counting method, power source voltage adjustment strategy and choice of counting points. Firstly, the circuit model of a wireless power system with multi-loads is built and the equation of each load is obtained. Secondly, after the counting method of electric vehicles is stated, the voltage adjustment strategy, based on the number of electric vehicles when the system is at a steady state, is set out. Then, the counting points are chosen according to power curves when the voltage adjustment strategy is adopted. Finally, an experimental prototype is implemented to verify the power stabilization strategy. The experimental results show that, with the application of this strategy, the charging power is stabilized with the fluctuation of no more than 5% when loads access randomly.

Development of a wireless protection against imitation system for identification and control of vehicle access

Directory of Open Access Journals (Sweden)

Aleksei A. Gavrishev

2018-03-01

Full Text Available This article deals with wireless systems for identification and control of vehicle access to protected objects. Known systems are considered. As a result, it has been established that one of the most promising approaches to identifying and controlling vehicle access to protected objects is the use of systems based on the "friend or foe" principle. Among these systems, there are "one-directional" and "bedirectional" identification and access control systems. "Bidirectional" systems are more preferable for questions of identification and access control. However, at present, these systems should have a reduced probability of recognizing the structure of the request and response signals because the potential attacker can easily perform unauthorized access to the radio channel of the system. On this basis, developed a wireless system identification and control vehicle access to protected objects based on the principle of "friend or foe", featuring increased protection from unauthorized access and jamming through the use of rewritable drives chaotic sequences. In addition, it’s proposed to use to identify the vehicle's RFID tag containing additional information about it. Are some specifications of the developed system (the possible frequency range of the request-response signals, the communication range, data rate, the size of the transmitted data, guidelines for choosing RFID. Also, with the help of fuzzy logic, was made the security assessment from unauthorized access request-response signals based on the system of "friend or foe", which are transferred via radio channel, developed systems and analogues. The security assessment of the developed system shows an adequate degree of protection against complex threats (view, spoofing, interception and jamming of traffic in comparison with known systems of this class. Among the main advantages of the developed system it’s necessary to mention increased security from unauthorized access and jamming

Broadband wireless communications for railway applications for onboard internet access and other applications

CERN Document Server

Masson, Émilie

2017-01-01

This book focuses on the needs of railway operators in terms of wireless communications, divided in two main categories: the commercial services and the operational needs. Then, all available technologies that can be used to provide Internet access on board trains and all the other operational applications requiring high capacity are detailed. Finally, challenges and trends in railway telecommunications are highlighted, through the presentation of the future and emerging technologies, the current discussions and works in the different authorities, and the key challenges and scientific barriers.

Non-Orthogonal Multiple Access for Ubiquitous Wireless Sensor Networks.

Science.gov (United States)

Anwar, Asim; Seet, Boon-Chong; Ding, Zhiguo

2018-02-08

Ubiquitous wireless sensor networks (UWSNs) have become a critical technology for enabling smart cities and other ubiquitous monitoring applications. Their deployment, however, can be seriously hampered by the spectrum available to the sheer number of sensors for communication. To support the communication needs of UWSNs without requiring more spectrum resources, the power-domain non-orthogonal multiple access (NOMA) technique originally proposed for 5th Generation (5G) cellular networks is investigated for UWSNs for the first time in this paper. However, unlike 5G networks that operate in the licensed spectrum, UWSNs mostly operate in unlicensed spectrum where sensors also experience cross-technology interferences from other devices sharing the same spectrum. In this paper, we model the interferences from various sources at the sensors using stochastic geometry framework. To evaluate the performance, we derive a theorem and present new closed form expression for the outage probability of the sensors in a downlink scenario under interference limited environment. In addition, diversity analysis for the ordered NOMA users is performed. Based on the derived outage probability, we evaluate the average link throughput and energy consumption efficiency of NOMA against conventional orthogonal multiple access (OMA) technique in UWSNs. Further, the required computational complexity for the NOMA users is presented.

Converged wireline and wireless signal transport over optical fibre access links

DEFF Research Database (Denmark)

Tafur Monroy, Idelfonso; Prince, Kamau; Osadchiy, Alexey Vladimirovich

2009-01-01

This article reviews emerging trends in converged optical-wireless communication systems and outline the role that photonic technologies are playing in making the vision of a wireline-wireless converged signal transport network a reality.......This article reviews emerging trends in converged optical-wireless communication systems and outline the role that photonic technologies are playing in making the vision of a wireline-wireless converged signal transport network a reality....

Advanced Signal Processing for Wireless Multimedia Communications

Directory of Open Access Journals (Sweden)

Xiaodong Wang

2000-01-01

Full Text Available There is at present a worldwide effort to develop next-generation wireless communication systems. It is envisioned that many of the future wireless systems will incorporate considerable signal-processing intelligence in order to provide advanced services such as multimedia transmission. In general, wireless channels can be very hostile media through which to communicate, due to substantial physical impediments, primarily radio-frequency interference and time-arying nature of the channel. The need of providing universal wireless access at high data-rate (which is the aim of many merging wireless applications presents a major technical challenge, and meeting this challenge necessitates the development of advanced signal processing techniques for multiple-access communications in non-stationary interference-rich environments. In this paper, we present some key advanced signal processing methodologies that have been developed in recent years for interference suppression in wireless networks. We will focus primarily on the problem of jointly suppressing multiple-access interference (MAI and intersymbol interference (ISI, which are the limiting sources of interference for the high data-rate wireless systems being proposed for many emerging application areas, such as wireless multimedia. We first present a signal subspace approach to blind joint suppression of MAI and ISI. We then discuss a powerful iterative technique for joint interference suppression and decoding, so-called Turbo multiuser detection, that is especially useful for wireless multimedia packet communications. We also discuss space-time processing methods that employ multiple antennas for interference rejection and signal enhancement. Finally, we touch briefly on the problems of suppressing narrowband interference and impulsive ambient noise, two other sources of radio-frequency interference present in wireless multimedia networks.

Comparison of Broadband Wireless Access Technology for HAPS Communication

Directory of Open Access Journals (Sweden)

Mingxiang GUAN

2014-03-01

Full Text Available An information system formed by HAP (High Altitude Platform will be a new generation-system for the wireless communications and HAPS (HAP Station communication system combines the advantages of both terrestrial and satellite communication systems and avoids, to different extents, their disadvantages. Third generation (3G mobile technology which is specified by the third generation partnership project (3 GPP is definitely one of the candidates. With the success of wireless network, the IEEE 802.16 standard, with its wireless metropolitan area network (MAN air interface appears to be a strong competitor. We provide initial practical comparison of these two technologies for HAPS Communication.

QoS Differentiated and Fair Packet Scheduling in Broadband Wireless Access Networks

Directory of Open Access Journals (Sweden)

Zhang Yan

2009-01-01

Full Text Available This paper studies the packet scheduling problem in Broadband Wireless Access (BWA networks. The key difficulties of the BWA scheduling problem lie in the high variability of wireless channel capacity and the unknown model of packet arrival process. It is difficult for traditional heuristic scheduling algorithms to handle the situation and guarantee satisfying performance in BWA networks. In this paper, we introduce learning-based approach for a better solution. Specifically, we formulate the packet scheduling problem as an average cost Semi-Markov Decision Process (SMDP. Then, we solve the SMDP by using reinforcement learning. A feature-based linear approximation and the Temporal-Difference learning technique are employed to produce a near optimal solution of the corresponding SMDP problem. The proposed algorithm, called Reinforcement Learning Scheduling (RLS, has in-built capability of self-training. It is able to adaptively and timely regulate its scheduling policy according to the instantaneous network conditions. Simulation results indicate that RLS outperforms two classical scheduling algorithms and simultaneously considers: (i effective QoS differentiation, (ii high bandwidth utilization, and (iii both short-term and long-term fairness.

The Prospects of Ultra-Broadband THz Wireless Communications

DEFF Research Database (Denmark)

Yu, Xianbin; Chen, Ying; Galili, Michael

2014-01-01

Wireless communications have entered into a path towards Terabit era, to accommodate the increasing demands on fast wireless access, e.g. huge data file transferring and fast mobile data access. Terahertz (THz) technology is considered feasible to carry ultrafast data signals, as it offers up...... to a few THz bandwidths. This paper overviews the prospects of Tbit/s wireless data rate and their potential applications. Technically, this talk reviews the key technologies and challenges to achieve an ultrafast wireless system operating in the THz frequency band, from viewpoint of communication......, in terms of ultrafast THz generation/THz detection and link power budget....

[Exploration of the design of media access control layer of wireless body area network for medical healthcare].

Science.gov (United States)

Liu, Xuemei; Ge, Baofeng

2012-04-01

This paper proposes a media access control (MAC) layer design for wireless body area network (WBAN) systems. WBAN is a technology that targets for wireless networking of wearable and implantable body sensors which monitor vital body signs, such as heart-rate, body temperature, blood pressure, etc. It has been receiving attentions from international organizations, e. g. the Institute of Electrical and Electronics Engineers (IEEE), due to its capability of providing efficient healthcare services and clinical management. This paper reviews the standardization procedure of WBAN and summarizes the challenge of the MAC layer design. It also discusses the methods of improving power consumption performance, which is one of the major issues of WBAN systems.

Delay-Aware Energy-Efficient Routing towards a Path-Fixed Mobile Sink in Industrial Wireless Sensor Networks

Science.gov (United States)

Wu, Shaobo; Chou, Wusheng; Niu, Jianwei; Guizani, Mohsen

2018-01-01

Wireless sensor networks (WSNs) involve more mobile elements with their widespread development in industries. Exploiting mobility present in WSNs for data collection can effectively improve the network performance. However, when the sink (i.e., data collector) path is fixed and the movement is uncontrollable, existing schemes fail to guarantee delay requirements while achieving high energy efficiency. This paper proposes a delay-aware energy-efficient routing algorithm for WSNs with a path-fixed mobile sink, named DERM, which can strike a desirable balance between the delivery latency and energy conservation. We characterize the object of DERM as realizing the energy-optimal anycast to time-varying destination regions, and introduce a location-based forwarding technique tailored for this problem. To reduce the control overhead, a lightweight sink location calibration method is devised, which cooperates with the rough estimation based on the mobility pattern to determine the sink location. We also design a fault-tolerant mechanism called track routing to tackle location errors for ensuring reliable and on-time data delivery. We comprehensively evaluate DERM by comparing it with two canonical routing schemes and a baseline solution presented in this work. Extensive evaluation results demonstrate that DERM can provide considerable energy savings while meeting the delay constraint and maintaining a high delivery ratio. PMID:29562628

Delay-Aware Energy-Efficient Routing towards a Path-Fixed Mobile Sink in Industrial Wireless Sensor Networks.

Science.gov (United States)

Wu, Shaobo; Chou, Wusheng; Niu, Jianwei; Guizani, Mohsen

2018-03-18

Wireless sensor networks (WSNs) involve more mobile elements with their widespread development in industries. Exploiting mobility present in WSNs for data collection can effectively improve the network performance. However, when the sink (i.e., data collector) path is fixed and the movement is uncontrollable, existing schemes fail to guarantee delay requirements while achieving high energy efficiency. This paper proposes a delay-aware energy-efficient routing algorithm for WSNs with a path-fixed mobile sink, named DERM, which can strike a desirable balance between the delivery latency and energy conservation. We characterize the object of DERM as realizing the energy-optimal anycast to time-varying destination regions, and introduce a location-based forwarding technique tailored for this problem. To reduce the control overhead, a lightweight sink location calibration method is devised, which cooperates with the rough estimation based on the mobility pattern to determine the sink location. We also design a fault-tolerant mechanism called track routing to tackle location errors for ensuring reliable and on-time data delivery. We comprehensively evaluate DERM by comparing it with two canonical routing schemes and a baseline solution presented in this work. Extensive evaluation results demonstrate that DERM can provide considerable energy savings while meeting the delay constraint and maintaining a high delivery ratio.

Delay-Aware Energy-Efficient Routing towards a Path-Fixed Mobile Sink in Industrial Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Shaobo Wu

2018-03-01

Full Text Available Wireless sensor networks (WSNs involve more mobile elements with their widespread development in industries. Exploiting mobility present in WSNs for data collection can effectively improve the network performance. However, when the sink (i.e., data collector path is fixed and the movement is uncontrollable, existing schemes fail to guarantee delay requirements while achieving high energy efficiency. This paper proposes a delay-aware energy-efficient routing algorithm for WSNs with a path-fixed mobile sink, named DERM, which can strike a desirable balance between the delivery latency and energy conservation. We characterize the object of DERM as realizing the energy-optimal anycast to time-varying destination regions, and introduce a location-based forwarding technique tailored for this problem. To reduce the control overhead, a lightweight sink location calibration method is devised, which cooperates with the rough estimation based on the mobility pattern to determine the sink location. We also design a fault-tolerant mechanism called track routing to tackle location errors for ensuring reliable and on-time data delivery. We comprehensively evaluate DERM by comparing it with two canonical routing schemes and a baseline solution presented in this work. Extensive evaluation results demonstrate that DERM can provide considerable energy savings while meeting the delay constraint and maintaining a high delivery ratio.

Optimal Pricing Strategy for Wireless Social Community Networks

OpenAIRE

Mazloumian, Amin; Manshaei, Mohammad Hossein; Felegyhazi, Mark; Hubaux, Jean-Pierre

2008-01-01

The increasing number of mobile applications fuels the demand for affordable and ubiquitous wireless access. The traditional wireless network technologies such as EV-DO or WiMAX provide this service but require a huge upfront investment in infrastructure and spectrum. On the contrary, as they do not have to face such an investment, social community operators rely on subscribers who constitute a community of users. The pricing strategy of the provided wireless access is an open problem for thi...

Intrusion detection and monitoring for wireless networks.

Energy Technology Data Exchange (ETDEWEB)

Thomas, Eric D.; Van Randwyk, Jamie A.; Lee, Erik J.; Stephano, Amanda (Indiana University); Tabriz, Parisa (University of Illinois at Urbana-Champaign); Pelon, Kristen (Cedarville University); McCoy, Damon (University of Colorado, Boulder); Lodato, Mark (Lafayette College); Hemingway, Franklin (University of New Mexico); Custer, Ryan P.; Averin, Dimitry (Polytechnic University); Franklin, Jason (Carnegie Mellon University); Kilman, Dominique Marie

2005-11-01

Wireless computer networks are increasing exponentially around the world. They are being implemented in both the unlicensed radio frequency (RF) spectrum (IEEE 802.11a/b/g) and the licensed spectrum (e.g., Firetide [1] and Motorola Canopy [2]). Wireless networks operating in the unlicensed spectrum are by far the most popular wireless computer networks in existence. The open (i.e., proprietary) nature of the IEEE 802.11 protocols and the availability of ''free'' RF spectrum have encouraged many producers of enterprise and common off-the-shelf (COTS) computer networking equipment to jump into the wireless arena. Competition between these companies has driven down the price of 802.11 wireless networking equipment and has improved user experiences with such equipment. The end result has been an increased adoption of the equipment by businesses and consumers, the establishment of the Wi-Fi Alliance [3], and widespread use of the Alliance's ''Wi-Fi'' moniker to describe these networks. Consumers use 802.11 equipment at home to reduce the burden of running wires in existing construction, facilitate the sharing of broadband Internet services with roommates or neighbors, and increase their range of ''connectedness''. Private businesses and government entities (at all levels) are deploying wireless networks to reduce wiring costs, increase employee mobility, enable non-employees to access the Internet, and create an added revenue stream to their existing business models (coffee houses, airports, hotels, etc.). Municipalities (Philadelphia; San Francisco; Grand Haven, MI) are deploying wireless networks so they can bring broadband Internet access to places lacking such access; offer limited-speed broadband access to impoverished communities; offer broadband in places, such as marinas and state parks, that are passed over by traditional broadband providers; and provide themselves with higher quality, more

Information Assurance in Wireless Networks

Science.gov (United States)

Kabara, Joseph; Krishnamurthy, Prashant; Tipper, David

2001-09-01

Emerging wireless networks will contain a hybrid infrastructure based on fixed, mobile and ad hoc topologies and technologies. In such a dynamic architecture, we define information assurance as the provisions for both information security and information availability. The implications of this definition are that the wireless network architecture must (a) provide sufficient security measures, (b) be survivable under node or link attack or failure and (c) be designed such that sufficient capacity remains for all critical services (and preferably most other services) in the event of attack or component failure. We have begun a research project to investigate the provision of information assurance for wireless networks viz. survivability, security and availability and here discuss the issues and challenges therein.

Energy-efficient wireless mesh infrastructures

OpenAIRE

Al-Hazmi, Y.; de Meer, Hermann; Hummel, Karin Anna; Meyer, Harald; Meo, Michela; Remondo Bueno, David

2011-01-01

The Internet comprises access segments with wired and wireless technologies. In the future, we can expect wireless mesh infrastructures (WMIs) to proliferate in this context. Due to the relatively low energy efficiency of wireless transmission, as compared to wired transmission, energy consumption of WMIs can represent a significant part of the energy consumption of the Internet as a whole. We explore different approaches to reduce energy consumption in WMIs, taking into accoun...

Quality of Recovery Evaluation of the Protection Schemes for Fiber-Wireless Access Networks

Science.gov (United States)

Fu, Minglei; Chai, Zhicheng; Le, Zichun

2016-03-01

With the rapid development of fiber-wireless (FiWi) access network, the protection schemes have got more and more attention due to the risk of huge data loss when failures occur. However, there are few studies on the performance evaluation of the FiWi protection schemes by the unified evaluation criterion. In this paper, quality of recovery (QoR) method was adopted to evaluate the performance of three typical protection schemes (MPMC scheme, OBOF scheme and RPMF scheme) against the segment-level failure in FiWi access network. The QoR models of the three schemes were derived in terms of availability, quality of backup path, recovery time and redundancy. To compare the performance of the three protection schemes comprehensively, five different classes of network services such as emergency service, prioritized elastic service, conversational service, etc. were utilized by means of assigning different QoR weights. Simulation results showed that, for the most service cases, RPMF scheme was proved to be the best solution to enhance the survivability when planning the FiWi access network.

Threats and risks to information security: a practical analysis of free access wireless networks

Science.gov (United States)

Quirumbay, Daniel I.; Coronel, Iván. A.; Bayas, Marcia M.; Rovira, Ronald H.; Gromaszek, Konrad; Tleshova, Akmaral; Kozbekova, Ainur

2017-08-01

Nowadays, there is an ever-growing need to investigate, consult and communicate through the internet. This need leads to the intensification of free access to the web in strategic and functional points for the benefit of the community. However, this open access is also related to the increase of information insecurity. The existing works on computer security primarily focus on the development of techniques to reduce cyber-attacks. However, these approaches do not address the sector of inexperienced users who have difficulty understanding browser settings. Two methods can solve this problem: first the development of friendly browsers with intuitive setups for new users and on the other hand, by implementing awareness programs on essential security without deepening on technical information. This article addresses an analysis of the vulnerabilities of wireless equipment that provides internet service in the open access zones and the potential risks that could be found when using these means.

Wireless local area network for the dental office.

Science.gov (United States)

Mupparapu, Muralidhar

2004-01-01

Dental offices are no exception to the implementation of new and advanced technology, especially if it enhances productivity. In a rapidly transforming digital world, wireless technology has a special place, as it has truly "retired the wire" and contributed to the ease and efficient access to patient data and other software-based applications for diagnosis and treatment. If the office or the clinic is networked, access to patient management software, imaging software and treatment planning tools is enhanced. Access will be further enhanced and unrestricted if the entire network is wireless. As with any new, emerging technology, there will be issues that should be kept in mind before adapting to the wireless environment. Foremost is the network security involved in the installation and use of these wireless networks. This short, technical manuscript deals with standards and choices in wireless technology currently available for implementation within a dental office. The benefits of each network security protocol available to protect patient data and boost the efficiency of a modern dental office are discussed.

The Most Possible Scheme of Joint Service Detection for the Next Wireless Communication Technologies

Directory of Open Access Journals (Sweden)

Firdaus Firdaus

2013-03-01

Full Text Available The era of beyond third generation wireless communication is highly heterogeneous in that it comprises several radio access technologies that need to be joined into a single multimode terminal. In this respect, this paper introduces a common service recognition system for the next wireless communication technologies i.e. Long Term Evolution (LTE, WiMAX or IEEE 802.16, and Wireless Local Area Network (WLAN or IEEE 802.11. It is done in physical layer as one of multimode terminal ability regardless network cooperation existence. We investigated on the preamble and synchronization signals as indicators of the available services instead of carrier frequency detection. To detect these signals, we proposed a time domain detection system consisting of auto-correlation, cross-correlation, and a peak period detection. Based on complexity analysis, this paper proposes the most possible scheme with lower complexity than cross-correlation implementation. Moreover, the fixed point simulation results show that the proposed system satisfies the minimum receiver sensitivity requirements that specified in the standards.

I-MAC: an incorporation MAC for wireless sensor networks

Science.gov (United States)

Zhao, Jumin; Li, Yikun; Li, Dengao; Lin, Xiaojie

2017-11-01

This paper proposes an innovative MAC protocol called I-MAC. Protocol for wireless sensor networks, which combines the advantages of collision tolerance and collision cancellation. The protocol increases the number of antenna in wireless sensor nodes. The purpose is to monitor the occurrence of packet collisions by increasing the number of antenna in real time. The built-in identity structure is used in the frame structure in order to help the sending node to identify the location of the receiving node after a data packet collision is detected. Packets can be recovered from where the conflict occurred. In this way, we can monitor the conflict for a fixed period of time. It can improve the channel utilisation through changing the transmission probability of collision nodes and solve the problem of hidden terminal through collision feedback mechanism. We have evaluated our protocol. Our results show that the throughput of I-MAC is 5 percentage points higher than that of carrier sense multiple access/collision notification. The network utilisation of I-MAC is more than 92%.

European Research towards Future Wireless Communications

DEFF Research Database (Denmark)

Frederiksen, Flemming Bjerge; Prasad, Ramjee; Pedersen, Gert Frølund

2005-01-01

This paper presents an overview of four on-going European research projects in the field of mobile and wireless communications leading to the next generations of wireless communications. The projects started in 2004. They investigate requirements and definition of access technology, network...

Sustainable and Practical Firmware Upgrade for Wireless Access Point Using Password-Based Authentication

Directory of Open Access Journals (Sweden)

Jaejin Jang

2016-08-01

Full Text Available Wireless access points (WAPs are devices that provide Internet connectivity to devices such as desktops, laptops, smartphones, and tablets. Hence, it is important to provide sufficient availability to devices and security for the traffic that is routed by a WAP. However, attackers can decrease the network bandwidth or obtain the traffic including private data such as search histories, login information, and device usage patterns by exploiting the vulnerabilities in firmware upgrades to install malicious firmware. To address this problem, we propose a sustainable and practical firmware upgrade for a WAP using password-based authentication. The proposed upgrade protocol ensures security by adding freshness to the firmware whenever a firmware upgrade occurs. This freshness is different for each event and each firmware; therefore, even if the freshness of one firmware is exposed, the others are secure. In addition, confidentiality, integrity, and authentication are ensured. Furthermore, the proposed protocol can be easily implemented and adapted to WAPs. Experiments are performed to evaluate the upgrade time, resource usage, and code size in wired and wireless connected environments by implementing a prototype and analyzing the security of the protocol. The results show that the proposed upgrade is secure and practical.

Strategies for P2P connectivity in reconfigurable converged wired/wireless access networks.

Science.gov (United States)

Puerto, Gustavo; Mora, José; Ortega, Beatriz; Capmany, José

2010-12-06

This paper presents different strategies to define the architecture of a Radio-Over-Fiber (RoF) Access networks enabling Peer-to-Peer (P2P) functionalities. The architectures fully exploit the flexibility of a wavelength router based on the feedback configuration of an Arrayed Waveguide Grating (AWG) and an optical switch to broadcast P2P services among diverse infrastructures featuring dynamic channel allocation and enabling an optical platform for 3G and beyond wireless backhaul requirements. The first architecture incorporates a tunable laser to generate a dedicated wavelength for P2P purposes and the second architecture takes advantage of reused wavelengths to enable the P2P connectivity among Optical Network Units (ONUs) or Base Stations (BS). While these two approaches allow the P2P connectivity in a one at a time basis (1:1), the third architecture enables the broadcasting of P2P sessions among different ONUs or BSs at the same time (1:M). Experimental assessment of the proposed architecture shows approximately 0.6% Error Vector Magnitude (EVM) degradation for wireless services and 1 dB penalty in average for 1 x 10(-12) Bit Error Rate (BER) for wired baseband services.

Broadband Access

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. Broadband Access. Worldwide market for broadband access $30 Billion! Over 200 million broadband subscribers worldwide! Various Competing Broadband access. Digital Subscriber line; Wireless; Optical Fiber.

Attacks on IEEE 802.11 wireless networks

Directory of Open Access Journals (Sweden)

Dejan Milan Tepšić

2013-06-01

Full Text Available Security of wireless computer networks was initially secured with the WEP security protocol, which relies on the RC4 encryption algorithm and the CRC algorithm to check the integrity. The basic problems of the WEP are a short initialization vector, unsafe data integrity checking, using a common key, the lack of mechanisms for management and exchange of keys, the lack of protection from the endless insertion of the same package into the network, the lack of authentication of access points and the like. The consequences of these failures are easy attacks against the WEP network, namely their complete insecurity. Therefore, the work began on the IEEE 802.11i protocol, which should radically improve the security of wireless networks. Since the development of a protocol lasted, the WPA standard was released to offset the security gap caused by the WEP. The WPA also relies on RC4 and CRC algorithms, but brings temporary keys and the MIC algorithm for data integrity. The 802.1X authentication was introduced and common keys are no longer needed, since it is possible to use an authentication server. The length of the initialization vector was increased and the vector is obtained based on the packet serial number, in order to prevent the insertion of the same packet into the network. The weakness of the WPA security mechanism is the use of a common key. WPA2 (802.11i later appeared. Unlike the WPA mechanism that worked on old devices with the replacement of software, WPA2 requires new network devices that can perform AES encryption. AES replaces the RC4 algorithm and delivers much greater security. Data integrity is protected by encryption. Despite progress, there are still weaknesses in wireless networks. Attacks for denial of service are possible as well as spoofing package headers attacks. For now, it is not advisable to use wireless networks in environments where unreliability and unavailability are not tolerated. Introduction In the entire history of

Optimal Pricing of Spectrum Resources in Wireless Opportunistic Access

Directory of Open Access Journals (Sweden)

Hanna Bogucka

2012-01-01

Full Text Available We consider opportunistic access to spectrum resources in cognitive wireless networks. The users equipment, or the network nodes in general are able to sense the spectrum and adopt a subset of available resources (the spectrum and the power individually and independently in a distributed manner, that is, based on their local channel quality information and not knowing the Channel State Information (CSI of the other nodes' links in the considered network area. In such a network scenery, the competition of nodes for available resources is observed, which can be modeled as a game. To obtain spectrally efficient and fair spectrum allocation in this competitive environment with the nodes having no information on the other players, taxation of resources is applied to coerce desired behavior of the competitors. In the paper, we present mathematical formulation of the problem of finding the optimal taxation rate (common for all nodes and propose a reduced-complexity algorithm for this optimization. Simulation results for these derived optimal values in various scenarios are also provided.

Fundamental Analysis of Extremely Fast Photonic THz Wireless Communication Systems

DEFF Research Database (Denmark)

Yu, Xianbin; Zhang, Xianmin

This talk will review the recent progress on developing THz communication systems for high speed wireless access, and fundamentally analyze the realistic throughput and accessible wireless range of a THz impulse radio communication link by employing a uni-travelling photodiode (UTC-PD) as emitter...

An Analysis Of Wireless Security

OpenAIRE

Salendra Prasad

2017-01-01

The WLAN security includes Wired Equivalent Primary WEP and WI-FI protected Access WPA. Today WEP is regarded as very poor security standard. WEP was regarded as very old security standard and has many security issues which users need to be addressed. In this Paper we will discuss Wireless Security and ways to improve on wireless security.

Resource slicing in virtual wireless networks: a survey

OpenAIRE

Richart, Matias; Baliosian De Lazzari, Javier Ernesto; Serrat Fernández, Juan; Gorricho Moreno, Juan Luis

2016-01-01

New architectural and design approaches for radio access networks have appeared with the introduction of network virtualization in the wireless domain. One of these approaches splits the wireless network infrastructure into isolated virtual slices under their own management, requirements, and characteristics. Despite the advances in wireless virtualization, there are still many open issues regarding the resource allocation and isolation of wireless slices. Because of the dynamics and share...

Wi-Fi Networks Security and Accessing Control

OpenAIRE

Tarek S. Sobh

2013-01-01

As wireless networks access gains popularity in corporate, private and personal networks, the nature of wireless networks opens up new possibilities for network attacks. This paper negotiating Wi-Fi security against scanning of rogue Wi-Fi networks and other related activities and considers the monitoring of Wi-Fi traffic effects. The unauthorized access point (AP) problem has raised more attention and resulted in obtaining wireless access without subscriber permission.This work assumes Wi-Fi...

Simulations of Large-scale WiFi-based Wireless Networks: Interdisciplinary Challenges and Applications

OpenAIRE

Nekovee, Maziar

2008-01-01

Wireless Fidelity (WiFi) is the fastest growing wireless technology to date. In addition to providing wire-free connectivity to the Internet WiFi technology also enables mobile devices to connect directly to each other and form highly dynamic wireless adhoc networks. Such distributed networks can be used to perform cooperative communication tasks such ad data routing and information dissemination in the absence of a fixed infrastructure. Furthermore, adhoc grids composed of wirelessly network...

An Access Control Protocol for Wireless Sensor Network Using Double Trapdoor Chameleon Hash Function

Directory of Open Access Journals (Sweden)

Tejeshwari Thakur

2016-01-01

Full Text Available Wireless sensor network (WSN, a type of communication system, is normally deployed into the unattended environment where the intended user can get access to the network. The sensor nodes collect data from this environment. If the data are valuable and confidential, then security measures are needed to protect them from the unauthorized access. This situation requires an access control protocol (ACP in the design of sensor network because of sensor nodes which are vulnerable to various malicious attacks during the authentication and key establishment and the new node addition phase. In this paper, we propose a secured ACP for such WSN. This protocol is based on Elliptic Curve Discrete Log Problem (ECDLP and double trapdoor chameleon hash function which secures the WSN from malicious attacks such as node masquerading attack, replay attack, man-in-the-middle attack, and forgery attacks. Proposed ACP has a special feature known as session key security. Also, the proposed ACP is more efficient as it requires only one modular multiplication during the initialization phase.

Challenging Aspects of Terahertz Terabit Wireless Communications

DEFF Research Database (Denmark)

Yu, Xianbin; Galili, Michael; Jepsen, Peter Uhd

The increasing demand on fast wireless communications, e.g. huge data file transferring and mobile broadband access, has driven wireless communication systems into a path towards Terabit era. Terahertz (THz) technology is promising due to its unique features, such as unlimited bandwidth available......, in terms of THz generation and link power budget. The THz atmospheric absorption is another critical issue to limit wireless communication range....

BLUETOOTH WIRELESS TECHNOLOGY: A MILESTONE IN ICT

African Journals Online (AJOL)

DJFLEX

This article summarizes the Bluetooth technology – a type of Wireless Personal Area Network (WPAN) with emphasis ... facilitating data transmission over short distances from fixed and ... primarily designed for low power consumption, with a.

Introduction to wireless sensor networks

CERN Document Server

Forster, Anna

2016-01-01

Explores real-world wireless sensor network development, deployment, and applications. The book begins with an introduction to wireless sensor networks and their fundamental concepts. Hardware components, operating systems, protocols, and algorithms that make up the anatomy of a sensor node are described in chapter two. Properties of wireless communications, medium access protocols, wireless links, and link estimation protocols are described in chapter three and chapter four. Routing basics and metrics, clustering techniques, time synchronization and localization protocols, as well as sensing techniques are introduced in chapter five to nine. The concluding chapter summarizes the learnt methods and shows how to use them to deploy real-world sensor networks in a structured way.

A Seamless Handoff Scheme with Access Point Load Balance for Real-Time Services Support in 802.11 Wireless LANs

Science.gov (United States)

Manodham, Thavisak; Loyola, Luis; Miki, Tetsuya

IEEE 802.11 wirelesses LANs (WLANs) have been rapidly deployed in enterprises, public areas, and households. Voice-over-IP (VoIP) and similar applications are now commonly used in mobile devices over wireless networks. Recent works have improved the quality of service (QoS) offering higher data rates to support various kinds of real-time applications. However, besides the need for higher data rates, seamless handoff and load balancing among APs are key issues that must be addressed in order to continue supporting real-time services across wireless LANs and providing fair services to all users. In this paper, we introduce a novel access point (AP) with two transceivers that improves network efficiency by supporting seamless handoff and traffic load balancing in a wireless network. In our proposed scheme, the novel AP uses the second transceiver to scan and find neighboring STAs in the transmission range and then sends the results to neighboring APs, which compare and analyze whether or not the STA should perform a handoff. The initial results from our simulations show that the novel AP module is more effective than the conventional scheme and a related work in terms of providing a handoff process with low latency and sharing traffic load with neighbor APs.

A medical-grade wireless architecture for remote electrocardiography.

Science.gov (United States)

Kang, Kyungtae; Park, Kyung-Joon; Song, Jae-Jin; Yoon, Chang-Hwan; Sha, Lui

2011-03-01

In telecardiology, electrocardiogram (ECG) signals from a patient are acquired by sensors and transmitted in real time to medical personnel across a wireless network. The use of IEEE 802.11 wireless LANs (WLANs), which are already deployed in many hospitals, can provide ubiquitous connectivity and thus allow cardiology patients greater mobility. However, engineering issues, including the error-prone nature of wireless channels and the unpredictable delay and jitter due to the nondeterministic nature of access to the wireless medium, need to be addressed before telecardiology can be safely realized. We propose a medical-grade WLAN architecture for remote ECG monitoring, which employs the point-coordination function (PCF) for medium access control and Reed-Solomon coding for error control. Realistic simulations with uncompressed two-lead ECG data from the MIT-BIH arrhythmia database demonstrate reliable wireless ECG monitoring; the reliability of ECG transmission exceeds 99.99% with the initial buffering delay of only 2.4 s.

Data aggregation in wireless sensor networks using the SOAP protocol

International Nuclear Information System (INIS)

Al-Yasiri, A; Sunley, A

2007-01-01

Wireless sensor networks (WSN) offer an increasingly attractive method of data gathering in distributed system architectures and dynamic access via wireless connectivity. Wireless sensor networks have physical and resource limitations, this leads to increased complexity for application developers and often results in applications that are closely coupled with network protocols. In this paper, a data aggregation framework using SOAP (Simple Object Access Protocol) on wireless sensor networks is presented. The framework works as a middleware for aggregating data measured by a number of nodes within a network. The aim of the study is to assess the suitability of the protocol in such environments where resources are limited compared to traditional networks

Data aggregation in wireless sensor networks using the SOAP protocol

Energy Technology Data Exchange (ETDEWEB)

Al-Yasiri, A; Sunley, A [School of Computing, Science and Engineering, University of Salford, Greater Manchester, M5 4WT (United Kingdom)

2007-07-15

Wireless sensor networks (WSN) offer an increasingly attractive method of data gathering in distributed system architectures and dynamic access via wireless connectivity. Wireless sensor networks have physical and resource limitations, this leads to increased complexity for application developers and often results in applications that are closely coupled with network protocols. In this paper, a data aggregation framework using SOAP (Simple Object Access Protocol) on wireless sensor networks is presented. The framework works as a middleware for aggregating data measured by a number of nodes within a network. The aim of the study is to assess the suitability of the protocol in such environments where resources are limited compared to traditional networks.

Wired and wireless convergent extended-reach optical access network using direct-detection of all-optical OFDM super-channel signal.

Science.gov (United States)

Chow, C W; Yeh, C H; Sung, J Y; Hsu, C W

2014-12-15

We propose and demonstrate the feasibility of using all-optical orthogonal frequency division multiplexing (AO-OFDM) for the convergent optical wired and wireless access networks. AO-OFDM relies on all-optically generated orthogonal subcarriers; hence, high data rate (> 100 Gb/s) can be easily achieved without hitting the speed limit of electronic digital-to-analog and analog-to-digital converters (DAC/ADC). A proof-of-concept convergent access network using AO-OFDM super-channel (SC) is demonstrated supporting 40 - 100 Gb/s wired and gigabit/s 100 GHz millimeter-wave (MMW) ROF transmissions.

Cognitive Radio Wireless Sensor Networks: Applications, Challenges and Research Trends

Science.gov (United States)

Joshi, Gyanendra Prasad; Nam, Seung Yeob; Kim, Sung Won

2013-01-01

A cognitive radio wireless sensor network is one of the candidate areas where cognitive techniques can be used for opportunistic spectrum access. Research in this area is still in its infancy, but it is progressing rapidly. The aim of this study is to classify the existing literature of this fast emerging application area of cognitive radio wireless sensor networks, highlight the key research that has already been undertaken, and indicate open problems. This paper describes the advantages of cognitive radio wireless sensor networks, the difference between ad hoc cognitive radio networks, wireless sensor networks, and cognitive radio wireless sensor networks, potential application areas of cognitive radio wireless sensor networks, challenges and research trend in cognitive radio wireless sensor networks. The sensing schemes suited for cognitive radio wireless sensor networks scenarios are discussed with an emphasis on cooperation and spectrum access methods that ensure the availability of the required QoS. Finally, this paper lists several open research challenges aimed at drawing the attention of the readers toward the important issues that need to be addressed before the vision of completely autonomous cognitive radio wireless sensor networks can be realized. PMID:23974152

Cognitive Radio Wireless Sensor Networks: Applications, Challenges and Research Trends

Directory of Open Access Journals (Sweden)

Gyanendra Prasad Joshi

2013-08-01

Full Text Available A cognitive radio wireless sensor network is one of the candidate areas where cognitive techniques can be used for opportunistic spectrum access. Research in this area is still in its infancy, but it is progressing rapidly. The aim of this study is to classify the existing literature of this fast emerging application area of cognitive radio wireless sensor networks, highlight the key research that has already been undertaken, and indicate open problems. This paper describes the advantages of cognitive radio wireless sensor networks, the difference between ad hoc cognitive radio networks, wireless sensor networks, and cognitive radio wireless sensor networks, potential application areas of cognitive radio wireless sensor networks, challenges and research trend in cognitive radio wireless sensor networks. The sensing schemes suited for cognitive radio wireless sensor networks scenarios are discussed with an emphasis on cooperation and spectrum access methods that ensure the availability of the required QoS. Finally, this paper lists several open research challenges aimed at drawing the attention of the readers toward the important issues that need to be addressed before the vision of completely autonomous cognitive radio wireless sensor networks can be realized.

Cognitive radio wireless sensor networks: applications, challenges and research trends.

Science.gov (United States)

Joshi, Gyanendra Prasad; Nam, Seung Yeob; Kim, Sung Won

2013-08-22

A cognitive radio wireless sensor network is one of the candidate areas where cognitive techniques can be used for opportunistic spectrum access. Research in this area is still in its infancy, but it is progressing rapidly. The aim of this study is to classify the existing literature of this fast emerging application area of cognitive radio wireless sensor networks, highlight the key research that has already been undertaken, and indicate open problems. This paper describes the advantages of cognitive radio wireless sensor networks, the difference between ad hoc cognitive radio networks, wireless sensor networks, and cognitive radio wireless sensor networks, potential application areas of cognitive radio wireless sensor networks, challenges and research trend in cognitive radio wireless sensor networks. The sensing schemes suited for cognitive radio wireless sensor networks scenarios are discussed with an emphasis on cooperation and spectrum access methods that ensure the availability of the required QoS. Finally, this paper lists several open research challenges aimed at drawing the attention of the readers toward the important issues that need to be addressed before the vision of completely autonomous cognitive radio wireless sensor networks can be realized.

Sustainable wireless networks

CERN Document Server

Zheng, Zhongming; Xuemin

2013-01-01

This brief focuses on network planning and resource allocation by jointly considering cost and energy sustainability in wireless networks with sustainable energy. The characteristics of green energy and investigating existing energy-efficient green approaches for wireless networks with sustainable energy is covered in the first part of this brief. The book then addresses the random availability and capacity of the energy supply. The authors explore how to maximize the energy sustainability of the network and minimize the failure probability that the mesh access points (APs) could deplete their

On Radio over Fiber for Heterogeneous Wireless Networks

DEFF Research Database (Denmark)

Riaz, M. Tahir; Nielsen, Rasmus Hjorth; Pedersen, Jens Myrup

2009-01-01

The paper provides an overview of the radio over fiber (RoF) technology and its potential use in heterogeneous wireless networks. Wireless communications have seen a huge growth in the last decade. It has been estimated that five in every six people in the entire world will have a mobile phone...... in 2010. The vast growing use of Internet on the mobile devices has also been increased significantly. In order to provide a broadband access for mobile communications, a new wireless infrastructure (fiber optic networks for distributed, extendible heterogeneous radio architectures and service...... provisioning - FUTON) based on RoF technology has been introduced. The project adopts centralized processing of radio signals for number of wireless base stations can enhance the network performance in terms of bandwidth, and QoS parameters. The simplified remote access units (RAU) are expected to not only...

WIRELESS TECHNOLOGIES for LOCATION-BASED SERVICES

Directory of Open Access Journals (Sweden)

Dewi Wirastuti

2012-06-01

Full Text Available This paper presents an overview of wireless technologies that support location-based services (LBS. Satellite and cellular networks have exploited their communication infrastructure to offer LBS. The rapid deployment of mobile broadband wireless networks has offered another appealing application area. Key to the realisation of LBS is an efficient and accurate positioning technique with various methods and offering different performance levels. So far, Global Positioning System (GPS has offered the best accuracy at a low cost but it is challenged by poor indoor coverage. With the rapid deployment of broadband wireless access ubiquitously, Mobile WiMAX (Worldwide Interoperability for Microwave Access is seen as a potential positioning option for LBS. Some key features of WiMAX, i.e., broadband benefit, high speed and large coverage area; it will be exploited to provide LBS.

Enhancing Cellular Coverage Quality by Virtual Access Point and Wireless Power Transfer

Directory of Open Access Journals (Sweden)

Jinsong Gui

2018-01-01

Full Text Available The ultradensification deploying for cellular networks is a direct and effective method for the improvement of network capacity. However, the benefit is achieved at the cost of network infrastructure investment and operating overheads, especially when there is big gap between peak-hour Internet traffic and average one. Therefore, we put forward the concept of virtual cellular coverage area, where wireless terminals with high-end configuration are motivated to enhance cellular coverage quality by both providing RF energy compensation and rewarding free traffic access to Internet. This problem is formulated as the Stackelberg game based on three-party circular decision, where a Macro BS (MBS acts as the leader to offer a charging power to Energy Transferring Relays (ETRs, and the ETRs and their associating Virtual Access Points (VAPs act as the followers to make their decisions, respectively. According to the feedback from the followers, the leader may readjust its strategy. The circular decision is repeated until the powers converge. Also, the better response algorithm for each game player is proposed to iteratively achieve the Stackelberg-Nash Equilibrium (SNE. Theoretical analysis proves the convergence of the proposed game scheme, and simulation results demonstrate its effectiveness.

Experiment of Wireless Sensor Network to Monitor Field Data

Directory of Open Access Journals (Sweden)

Kwang Sik Kim

2009-08-01

Full Text Available Recently the mobile wireless network has been drastically enhanced and one of the most efficient ways to realize the ubiquitous network will be to develop the converged network by integrating the mobile wireless network with other IP fixed network like NGN (Next Generation Network. So in this paper the term of the wireless ubiquitous network is used to describe this approach. In this paper, first, the wireless ubiquitous network architecture is described based on IMS which has been standardized by 3GPP (3rd Generation Partnership Program. Next, the field data collection system to match the satellite data using location information is proposed based on the concept of the wireless ubiquitous network architecture. The purpose of the proposed system is to provide more accurate analyzing method with the researchers in the remote sensing area.

Flexible network wireless transceiver and flexible network telemetry transceiver

Science.gov (United States)

Brown, Kenneth D.

2008-08-05

A transceiver for facilitating two-way wireless communication between a baseband application and other nodes in a wireless network, wherein the transceiver provides baseband communication networking and necessary configuration and control functions along with transmitter, receiver, and antenna functions to enable the wireless communication. More specifically, the transceiver provides a long-range wireless duplex communication node or channel between the baseband application, which is associated with a mobile or fixed space, air, water, or ground vehicle or other platform, and other nodes in the wireless network or grid. The transceiver broadly comprises a communication processor; a flexible telemetry transceiver including a receiver and a transmitter; a power conversion and regulation mechanism; a diplexer; and a phased array antenna system, wherein these various components and certain subcomponents thereof may be separately enclosed and distributable relative to the other components and subcomponents.

Service time analysis of secondary packet transmission with opportunistic channel access

KAUST Repository

Usman, Muneer; Yang, Hongchuan; Alouini, Mohamed-Slim

2014-01-01

Cognitive radio transceiver can opportunistically access the underutilized channels of primary systems for new wireless services. The secondary transmission may be interrupted by the primary user's transmission. To facilitate the delay analysis of such secondary packet transmission, we study the resulting extended delivery time for a fixed-size secondary packet that includes both transmission time and waiting time. In particular we derive the exact distribution functions of extended delivery time of secondary transmission for both continuous sensing and periodic sensing cases. Selected numerical results are presented for illustrating the mathematical formulation.

Service time analysis of secondary packet transmission with opportunistic channel access

KAUST Repository

Usman, Muneer

2014-09-01

Cognitive radio transceiver can opportunistically access the underutilized channels of primary systems for new wireless services. The secondary transmission may be interrupted by the primary user\\'s transmission. To facilitate the delay analysis of such secondary packet transmission, we study the resulting extended delivery time for a fixed-size secondary packet that includes both transmission time and waiting time. In particular we derive the exact distribution functions of extended delivery time of secondary transmission for both continuous sensing and periodic sensing cases. Selected numerical results are presented for illustrating the mathematical formulation.

Performance evaluation of modulation and multiple access schemes in ultraviolet optical wireless connections for two atmosphere thickness cases.

Science.gov (United States)

Raptis, Nikos; Pikasis, Evangelos; Syvridis, Dimitris

2016-08-01

The exploitation of optical wireless communication channels in a non-line-of-sight regime is studied for point-to-point and networking configurations considering the use of light-emitting diodes. Two environments with different scattering center densities are considered, assuming operation at 265 nm. The bit error rate performance of both pulsed and multicarrier modulation schemes is examined, using numerical approaches. In the networking scenario, a central node only receives data, one node transmits useful data, and the rest of them act as interferers. The performance of the desirable node's transmissions is evaluated. The access to the medium is controlled by a code division multiple access scheme.

Transmission Delay Based Control over Networks with Wireless Links

Institute of Scientific and Technical Information of China (English)

无

2002-01-01

To achieve the mobility of computers during communication, the TCP connections between fixed host and mobile host may often traverse wired and wireless networks, and the recovery of losses due to wireless transmission error is much different from congestion control. The paper analyzes the side effect of RTT estimation while making the TCP source to handle congestion and wireless error losses properly. Then present a strategy using information feedback by the last hop acknowledgement and monitoring the queuing level of the wired bottleneck link by calculating the changes in transmission delay along the path. With the identification of the early stage of congestion, it can respond to wired congestion quickly while keeping wireless link more reliable, and make TCP react to the different packets losses more appropriately.

Adoption of wireless internet parks: An empirical study in Qatar

OpenAIRE

Weerakkody, V

2008-01-01

This paper examines the adoption of free wireless internet parks (iPark) by Qatari citizens as means of accessing electronic services from public parks. The Qatar government has launched the iPark concept with a view of providing free internet access for all citizens while enjoying the outdoors. By offering free wireless Internet access, the Qatari government encourages its citizen's to actively participate in the global information society with a view of bridging the digital divide. Using a ...

Frameless ALOHA Protocol for Wireless Networks

DEFF Research Database (Denmark)

Stefanovic, Cedomir; Popovski, Petar; Vukobratovic, Dejan

2012-01-01

We propose a novel distributed random access scheme for wireless networks based on slotted ALOHA, motivated by the analogies between successive interference cancellation and iterative belief-propagation decoding on erasure channels. The proposed scheme assumes that each user independently accesse...

Networking wireless sensors

National Research Council Canada - National Science Library

Krishnamachari, Bhaskar

2005-01-01

... by networking techniques across multiple layers. The topics covered include network deployment, localization, time synchronization, wireless radio characteristics, medium-access, topology control, routing, data-centric techniques, and transport protocols. Ideal for researchers and designers seeking to create new algorithms and protocols and enginee...

Economics and Governance of the wireless Internet

DEFF Research Database (Denmark)

Falch, Morten; Henten, Anders; Tadayoni, Reza

barriers of entry. In this paper three issues are discussed: 1) Developments in pricing schemes for Internet interconnection and Internet access with special focus on the role of wireless access. 2) Developments in supporting infrastructures with special focus on the increasing role of wireless......The Internet has undergone a growing diversification with regard to types of users, kinds of services and use of transmission technologies and infrastructures. Today, internet services are delivered by the use of many different wired and wireless communication technologies with different technical...... capabilities and limitations, and with different techno-economic characteristics. The question is whether these trends challenge the current mode of governance for the Internet. In the early days, the Internet was considered to be open, free, competitive, with a high level of entrepreneurialism, and with low...

Design and implementation about the campus wireless network

International Nuclear Information System (INIS)

Qi Fazhi; An Dehai; Wang Yanming; Cui Tao; Chen Gang; Liu Baoxu

2007-01-01

With the development of network applications, flexibility and wieldy is becoming more and more important for network users. Based on the analysis of the needs of campus wireless network. This article design and analysis the deployment mechanism, register system and protection system of wireless network. Built a wireless network system base on IHEP network environment, realization the 'always and everywhere' access the network in the IHEP campus area. (authors)

Introductory survey for wireless infrared communications

Directory of Open Access Journals (Sweden)

Munsif Ali Jatoi

2014-08-01

Full Text Available Wireless infrared communications can be defined as the propagation of light waves in free space using infrared radiation whose range is 400–700 nm. This range corresponds to frequencies of hundreds of terahertz, which is high for higher data rate applications. Wireless infrared is applied for higher data rates applications such as wireless computing, wireless video and wireless multimedia communication applications. Introduced by Gfeller, this field has grown with different link configurations, improved transmitter efficiency, increased receiver responsivity and various multiple access techniques for improved quality. Errors are caused because of background light, which causes degradation overall system performance. Error correction techniques are used to remove the errors caused during transmission. This study provides a brief account on field theory used for error correction in wireless infrared systems. The results are produced in terms of bit error rate and signal-to-noise ratio for various bit lengths to show the ability of encoding and decoding algorithms.

Architectural and Mobility Management Designs in Internet-Based Infrastructure Wireless Mesh Networks

Science.gov (United States)

Zhao, Weiyi

2011-01-01

Wireless mesh networks (WMNs) have recently emerged to be a cost-effective solution to support large-scale wireless Internet access. They have numerous applications, such as broadband Internet access, building automation, and intelligent transportation systems. One research challenge for Internet-based WMNs is to design efficient mobility…

Wireless Network Penetration Testing and Security Auditing

Directory of Open Access Journals (Sweden)

Wang Shao-Long

2016-01-01

Full Text Available IEEE802.11 wireless wireless networks have security issues that are vulnerable to a variety of attacks. Due to using radio to transport data, attackers can bypass firewalls, sniff sensitive information, intercept packets and send malicious packets. Security auditing and penetration testing is expected to ensure wireless networks security. The contributions of this work are analyzed the vulnerability and types of attacks pertaining to IEEE 802.11 WLAN, performed well known attacks in a laboratory environment to conduct penetration tests to confirm whether our wireless network is hackable or not. WAIDPS is configured as auditing tool to view wireless attacks, such as WEP/WPA/WPA2 cracking, rouge access points, denial of service attack. WAIDPS is designed to detect wireless intrusion with additional features. Penetration testing and auditing will mitigate the risk and threatening to protect WALN.

60 GHz Wireless Propagation Channels: Characterization, Modeling and Evaluation

OpenAIRE

Gustafson, Carl

2014-01-01

To be able to connect wirelessly to the internet is nowadays a part of everyday life and the number of wireless devices accessing wireless networks worldwide are increasing rapidly. However, with the increasing number of wireless devices and applications and the amount available bandwidth, spectrum shortage is an issue. A promising way to increase the amount of available spectrum is to utilize frequency bands in the mm-wave range of 30-300 GHz that previously have not been used for typical co...

Experience of wireless local area network in a radiation oncology department.

Science.gov (United States)

Mandal, Abhijit; Asthana, Anupam Kumar; Aggarwal, Lalit Mohan

2010-01-01

The aim of this work is to develop a wireless local area network (LAN) between different types of users (Radiation Oncologists, Radiological Physicists, Radiation Technologists, etc) for efficient patient data management and to made easy the availability of information (chair side) to improve the quality of patient care in Radiation Oncology department. We have used mobile workstations (Laptops) and stationary workstations, all equipped with wireless-fidelity (Wi-Fi) access. Wireless standard 802.11g (as recommended by Institute of Electrical and Electronic Engineers (IEEE, Piscataway, NJ) has been used. The wireless networking was configured with the Service Set Identifier (SSID), Media Access Control (MAC) address filtering, and Wired Equivalent Privacy (WEP) network securities. We are successfully using this wireless network in sharing the indigenously developed patient information management software. The proper selection of the hardware and the software combined with a secure wireless LAN setup will lead to a more efficient and productive radiation oncology department.

A Calibrated Test-Set for Measurement of Access-Point Time Specifications in Hybrid Wired/Wireless Industrial Communication †

Directory of Open Access Journals (Sweden)

Federico Tramarin

2018-05-01

Full Text Available In factory automation and process control systems, hybrid wired/wireless networks are often deployed to connect devices of difficult reachability such as those mounted on mobile equipment. A widespread implementation of these networks makes use of Access Points (APs to implement wireless extensions of Real-Time Ethernet (RTE networks via the IEEE 802.11 Wireless LAN (WLAN. Unfortunately, APs may introduce random delays in frame forwarding, mainly related to their internal behavior (e.g., queue management, processing times, that clearly impact the overall worst case execution time of real-time tasks involved in industrial process control systems. As a consequence, the knowledge of such delays becomes a crucial design parameter, and their estimation is definitely of utter importance. In this scenario, the paper presents an original and effective method to measure the aforementioned delays introduced by APs, exploiting a hybrid loop-back link and a simple, yet accurate set-up with moderate instrumentation requirements. The proposed method, which requires an initial calibration phase by means of a reference AP, has been successfully tested on some commercial APs to prove its effectiveness. The proposed measurement procedure is proven to be general and, as such, can be profitably adopted in even different scenarios.

Airborne wireless communication systems, airborne communication methods, and communication methods

Science.gov (United States)

Deaton, Juan D [Menan, ID; Schmitt, Michael J [Idaho Falls, ID; Jones, Warren F [Idaho Falls, ID

2011-12-13

An airborne wireless communication system includes circuitry configured to access information describing a configuration of a terrestrial wireless communication base station that has become disabled. The terrestrial base station is configured to implement wireless communication between wireless devices located within a geographical area and a network when the terrestrial base station is not disabled. The circuitry is further configured, based on the information, to configure the airborne station to have the configuration of the terrestrial base station. An airborne communication method includes answering a 911 call from a terrestrial cellular wireless phone using an airborne wireless communication system.

A Model for QoS - Aware Wireless Communication in Hospitals.

Science.gov (United States)

Alavikia, Zahra; Khadivi, Pejman; Hashemi, Masoud Reza

2012-01-01

In the recent decade, research regarding wireless applications in electronic health (e-Health) services has been increasing. The main benefits of using wireless technologies in e-Health applications are simple communications, fast delivery of medical information, reducing treatment cost and also reducing the medical workers' error rate. However, using wireless communications in sensitive healthcare environment raises electromagnetic interference (EMI). One of the most effective methods to avoid the EMI problem is power management. To this end, some of methods have been proposed in the literature to reduce EMI effects in health care environments. However, using these methods may result in nonaccurate interference avoidance and also may increase network complexity. To overcome these problems, we introduce two approaches based on per-user location and hospital sectoring for power management in sensitive healthcare environments. Although reducing transmission power could avoid EMI, it causes a number of successful message deliveries to the access point to decrease and, hence, the quality of service requirements cannot be meet. In this paper, we propose the use of relays for decreasing the probability of outage in the aforementioned scenario. Relay placement is the main factor to enjoy the usefulness of relay station benefits in the network and, therefore, we use the genetic algorithm to compute the optimum positions of a fixed number of relays. We have considered delay and maximum blind point coverage as two main criteria in relay station problem. The performance of the proposed method in outage reduction is investigated through simulations.

Optical wireless connected objects for healthcare.

Science.gov (United States)

Toumieux, Pascal; Chevalier, Ludovic; Sahuguède, Stéphanie; Julien-Vergonjanne, Anne

2015-10-01

In this Letter the authors explore the communication capabilities of optical wireless technology for a wearable device dedicated to healthcare application. In an indoor environment sensible to electromagnetic perturbations such as a hospital, the use of optical wireless links can permit reducing the amount of radio frequencies in the patient environment. Moreover, this technology presents the advantage to be secure, low-cost and easy to deploy. On the basis of commercially available components, a custom-made wearable device is presented, which allows optical wireless transmission of accelerometer data in the context of physical activity supervision of post-stroke patients in hospital. Considering patient mobility, the experimental performance is established in terms of packet loss as a function of the number of receivers fixed to the ceiling. The results permit to conclude that optical wireless links can be used to perform such mobile remote monitoring applications. Moreover, based on the measurements obtained with one receiver, it is possible to theoretically determine the performance according to the number of receivers to be deployed.

Data security issues arising from integration of wireless access into healthcare networks.

Science.gov (United States)

Frenzel, John C

2003-04-01

The versatility of having Ethernet speed connectivity without wires is rapidly driving adoption of wireless data networking by end users across all types of industry. Designed to be easy to configure and work among diverse platforms, wireless brings online data to mobile users. This functionality is particularly useful in modern clinical medicine. Wireless presents operators of networks containing or transmitting sensitive and confidential data with several new types of security vulnerabilities, and potentially opens previously protected core network resources to outside attack. Herein, we review the types of vulnerabilities, the tools necessary to exploit them, and strategies to thwart a successful attack.

Revenue-Maximizing Radio Access Technology Selection with Net Neutrality Compliance in Heterogeneous Wireless Networks

Directory of Open Access Journals (Sweden)

Elissar Khloussy

2018-01-01

Full Text Available The net neutrality principle states that users should have equal access to all Internet content and that Internet Service Providers (ISPs should not practice differentiated treatment on any of the Internet traffic. While net neutrality aims to restrain any kind of discrimination, it also grants exemption to a certain category of traffic known as specialized services (SS, by allowing the ISP to dedicate part of the resources for the latter. In this work, we consider a heterogeneous LTE/WiFi wireless network and we investigate revenue-maximizing Radio Access Technology (RAT selection strategies that are net neutrality-compliant, with exemption granted to SS traffic. Our objective is to find out how the bandwidth reservation for SS traffic would be made in a way that allows maximizing the revenue while being in compliance with net neutrality and how the choice of the ratio of reserved bandwidth would affect the revenue. The results show that reserving bandwidth for SS traffic in one RAT (LTE can achieve higher revenue. On the other hand, when the capacity is reserved across both LTE and WiFi, higher social benefit in terms of number of admitted users can be realized, as well as lower blocking probability for the Internet access traffic.

Wireless multimedia communication systems design, analysis, and implementation

CERN Document Server

Rao, KR; Bakmaz, Bojan M

2014-01-01

Rapid progress in software, hardware, mobile networks, and the potential of interactive media poses many questions for researchers, manufacturers, and operators of wireless multimedia communication systems. Wireless Multimedia Communication Systems: Design, Analysis, and Implementation strives to answer those questions by not only covering the underlying concepts involved in the design, analysis, and implementation of wireless multimedia communication systems, but also by tackling advanced topics such as mobility management, security components, and smart grids.Offering an accessible treatment

Cross-layer design for radio resource allocation based on priority scheduling in OFDMA wireless access network

Directory of Open Access Journals (Sweden)

Chen Yen-Wen

2011-01-01

Full Text Available Abstract The orthogonal frequency-division multiple access (OFDMA system has the advantages of flexible subcarrier allocation and adaptive modulation with respect to channel conditions. However, transmission overhead is required in each frame to broadcast the arrangement of radio resources to all mobile stations within the coverage of the same base station. This overhead greatly affects the utilization of valuable radio resources. In this paper, a cross layer scheme is proposed to reduce the number of traffic bursts at the downlink of an OFDMA wireless access network so that the overhead of the media access protocol (MAP field can be minimized. The proposed scheme considers the priorities and the channel conditions of quality of service (QoS traffic streams to arrange for them to be sent with minimum bursts in a heuristic manner. In addition, the trade-off between the degradation of the modulation level and the reduction of traffic bursts is investigated. Simulation results show that the proposed scheme can effectively reduce the traffic bursts and, therefore, increase resource utilization.

Accessing data transfer reliability for duty cycled mobile wireless sensor network

International Nuclear Information System (INIS)

Shaikh, F.K.

2014-01-01

Mobility in WSNs (Wireless Sensor Networks) introduces significant challenges which do not arise in static WSNs. Reliable data transport is an important aspect of attaining consistency and QoS (Quality of Service) in several applications of MWSNs (Mobile Wireless Sensor Networks). It is important to understand how each of the wireless sensor networking characteristics such as duty cycling, collisions, contention and mobility affects the reliability of data transfer. If reliability is not managed well, the MWSN can suffer from overheads which reduce its applicability in the real world. In this paper, reliability assessment is being studied by deploying MWSN in different indoor and outdoor scenarios with various duty cycles of the motes and speeds of the mobile mote. Results show that the reliability is greatly affected by the duty cycled motes and the mobility using inherent broadcast mechanisms. (author)

Spread Spectrum Techniques and their Applications to Wireless Communications

DEFF Research Database (Denmark)

Prasad, Ramjee; Cianca, E.

2005-01-01

Spread Spectrum (SS) radio communications is on the verge of potentially explosive commercial development An SS-based multiple access, such as CDMA, has been chosen for 3G wireless communications. Other current applications of SS techniues are in Wireless LANs and Satellite Navigation Systems...

Competition in the domain of wireless networks security

Science.gov (United States)

Bednarczyk, Mariusz

2017-04-01

Wireless networks are very popular and have found wide spread usage amongst various segments, also in military environment. The deployment of wireless infrastructures allow to reduce the time it takes to install and dismantle communications networks. With wireless, users are more mobile and can easily get access to the network resources all the time. However, wireless technologies like WiFi or Bluetooth have security issues that hackers have extensively exploited over the years. In the paper several serious security flaws in wireless technologies are presented. Most of them enable to get access to the internal networks and easily carry out man-in-the-middle attacks. Very often, they are used to launch massive denial of service attacks that target the physical infrastructure as well as the RF spectrum. For instance, there are well known instances of Bluetooth connection spoofing in order to steal WiFi password stored in the mobile device. To raise the security awareness and protect wireless networks against an adversary attack, an analysis of attack methods and tools over time is presented in the article. The particular attention is paid to the severity, possible targets as well as the ability to persist in the context of protective measures. Results show that an adversary can take complete control of the victims' mobile device features if the users forget to use simple safety principles.

Accounting for Energy Cost When Designing Energy-Efficient Wireless Access Networks

Directory of Open Access Journals (Sweden)

Greta Vallero

2018-03-01

Full Text Available Because of the increase of the data traffic demand, wireless access networks, through which users access telecommunication services, have expanded, in terms of size and of capability and, consequently, in terms of power consumption. Therefore, costs to buy the necessary power for the supply of base stations of those networks is becoming very high, impacting the communication cost. In this study, strategies to reduce the amount of money spent for the purchase of the energy consumed by the base stations are proposed for a network powered by solar panels, energy batteries and the power grid. First, the variability of the energy prices is exploited. It provides a cost reduction of up to 30%, when energy is bought in advance. If a part of the base stations is deactivated when the energy price is higher than a given threshold, a compromise between the energy cost and the user coverage drop is needed. In the simulated scenario, the necessary energy cost can be reduced by more than 40%, preserving the user coverage by greater than 94%. Second, the network is introduced to the energy market: it buys and sells energy from/to the traditional power grid. Finally, costs are reduced by the reduction of power consumption of the network, achieved by using microcell base stations. In the considered scenario, up to a 31% cost reduction is obtained, without the deterioration of the quality of service, but a huge Capex expenditure is required.

Real-Time Communication in Wireless Home Networks

NARCIS (Netherlands)

Scholten, Johan; Jansen, P.G.

This paper describes a medium access protocol for real-time communication in wireless networks. Medium access is controlled by a scheduler, which utilizes a pre-emptive earliest deadline first (PEDF) scheduling algorithm. The scheduler prevents collisions in the network, where normally only

Insecurity of Wireless Networks

Energy Technology Data Exchange (ETDEWEB)

Sheldon, Frederick T [ORNL; Weber, John Mark [Dynetics, Inc.; Yoo, Seong-Moo [University of Alabama, Huntsville; Pan, W. David [University of Alabama, Huntsville

2012-01-01

Wireless is a powerful core technology enabling our global digital infrastructure. Wi-Fi networks are susceptible to attacks on Wired Equivalency Privacy, Wi-Fi Protected Access (WPA), and WPA2. These attack signatures can be profiled into a system that defends against such attacks on the basis of their inherent characteristics. Wi-Fi is the standard protocol for wireless networks used extensively in US critical infrastructures. Since the Wired Equivalency Privacy (WEP) security protocol was broken, the Wi-Fi Protected Access (WPA) protocol has been considered the secure alternative compatible with hardware developed for WEP. However, in November 2008, researchers developed an attack on WPA, allowing forgery of Address Resolution Protocol (ARP) packets. Subsequent enhancements have enabled ARP poisoning, cryptosystem denial of service, and man-in-the-middle attacks. Open source systems and methods (OSSM) have long been used to secure networks against such attacks. This article reviews OSSMs and the results of experimental attacks on WPA. These experiments re-created current attacks in a laboratory setting, recording both wired and wireless traffic. The article discusses methods of intrusion detection and prevention in the context of cyber physical protection of critical Internet infrastructure. The basis for this research is a specialized (and undoubtedly incomplete) taxonomy of Wi-Fi attacks and their adaptations to existing countermeasures and protocol revisions. Ultimately, this article aims to provide a clearer picture of how and why wireless protection protocols and encryption must achieve a more scientific basis for detecting and preventing such attacks.

Performance Analysis of Cluster Formation in Wireless Sensor Networks.

Science.gov (United States)

Montiel, Edgar Romo; Rivero-Angeles, Mario E; Rubino, Gerardo; Molina-Lozano, Heron; Menchaca-Mendez, Rolando; Menchaca-Mendez, Ricardo

2017-12-13

Clustered-based wireless sensor networks have been extensively used in the literature in order to achieve considerable energy consumption reductions. However, two aspects of such systems have been largely overlooked. Namely, the transmission probability used during the cluster formation phase and the way in which cluster heads are selected. Both of these issues have an important impact on the performance of the system. For the former, it is common to consider that sensor nodes in a clustered-based Wireless Sensor Network (WSN) use a fixed transmission probability to send control data in order to build the clusters. However, due to the highly variable conditions experienced by these networks, a fixed transmission probability may lead to extra energy consumption. In view of this, three different transmission probability strategies are studied: optimal, fixed and adaptive. In this context, we also investigate cluster head selection schemes, specifically, we consider two intelligent schemes based on the fuzzy C-means and k-medoids algorithms and a random selection with no intelligence. We show that the use of intelligent schemes greatly improves the performance of the system, but their use entails higher complexity and selection delay. The main performance metrics considered in this work are energy consumption, successful transmission probability and cluster formation latency. As an additional feature of this work, we study the effect of errors in the wireless channel and the impact on the performance of the system under the different transmission probability schemes.

Performance Analysis of Cluster Formation in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Edgar Romo Montiel

2017-12-01

Full Text Available Clustered-based wireless sensor networks have been extensively used in the literature in order to achieve considerable energy consumption reductions. However, two aspects of such systems have been largely overlooked. Namely, the transmission probability used during the cluster formation phase and the way in which cluster heads are selected. Both of these issues have an important impact on the performance of the system. For the former, it is common to consider that sensor nodes in a clustered-based Wireless Sensor Network (WSN use a fixed transmission probability to send control data in order to build the clusters. However, due to the highly variable conditions experienced by these networks, a fixed transmission probability may lead to extra energy consumption. In view of this, three different transmission probability strategies are studied: optimal, fixed and adaptive. In this context, we also investigate cluster head selection schemes, specifically, we consider two intelligent schemes based on the fuzzy C-means and k-medoids algorithms and a random selection with no intelligence. We show that the use of intelligent schemes greatly improves the performance of the system, but their use entails higher complexity and selection delay. The main performance metrics considered in this work are energy consumption, successful transmission probability and cluster formation latency. As an additional feature of this work, we study the effect of errors in the wireless channel and the impact on the performance of the system under the different transmission probability schemes.

Using digital watermarking to enhance security in wireless medical image transmission.

Science.gov (United States)

Giakoumaki, Aggeliki; Perakis, Konstantinos; Banitsas, Konstantinos; Giokas, Konstantinos; Tachakra, Sapal; Koutsouris, Dimitris

2010-04-01

During the last few years, wireless networks have been increasingly used both inside hospitals and in patients' homes to transmit medical information. In general, wireless networks suffer from decreased security. However, digital watermarking can be used to secure medical information. In this study, we focused on combining wireless transmission and digital watermarking technologies to better secure the transmission of medical images within and outside the hospital. We utilized an integrated system comprising the wireless network and the digital watermarking module to conduct a series of tests. The test results were evaluated by medical consultants. They concluded that the images suffered no visible quality degradation and maintained their diagnostic integrity. The proposed integrated system presented reasonable stability, and its performance was comparable to that of a fixed network. This system can enhance security during the transmission of medical images through a wireless channel.

Use of consumer wireless devices by South Africans with severe communication disability.

Science.gov (United States)

Bornman, Juan; Bryen, Diane Nelson; Moolman, Enid; Morris, John

2016-01-01

Advancements in wireless technology (e.g. cell phones and tablets) have opened new communication opportunities and environments for individuals with severe communication disabilities. The advancement of these technologies poses challenges to ensuring that these individuals enjoy equal access to this increasingly essential technology. However, a paucity of research exists. To describe the nature and frequency with which South African adults with severe communication disabilities have access to and use wireless devices, as well as the types of activities for which wireless devices are used. Survey research was conducted with 30 individuals who use augmentative and alternative communication (AAC) technology using the Survey of User Needs Questionnaire developed in the United States, and localized to the South African context. All participants, despite their limited education, unemployment and low economic status, owned and/or used mainstream wireless devices. Slightly more than half of the participants (53.3%) needed adaptations to their wireless devices. Advantages of using wireless devices were highlighted, including connecting with others (through using text messaging, social networking, making plans with others, sharing photos and videos with friends), for leisure activities (e.g. listening to music, watching videos, playing games), and for safety purposes (e.g. to navigate when lost, using the device when in trouble and needing immediate assistance). These wireless devices offer substantial benefits and opportunities to individuals with disabilities who rely on AAC in terms of independence, social participation, education and safety/security. However, they still do not enjoy equal opportunity to access and use wireless devices relative to the non-disabled population.

Reliable and Efficient Communications in Wireless Sensor Networks

International Nuclear Information System (INIS)

Abdelhakim, M.M.

2014-01-01

Wireless sensor network (WSN) is a key technology for a wide range of military and civilian applications. Limited by the energy resources and processing capabilities of the sensor nodes, reliable and efficient communications in wireless sensor networks are challenging, especially when the sensors are deployed in hostile environments. This research aims to improve the reliability and efficiency of time-critical communications in WSNs, under both benign and hostile environments. We start with wireless sensor network with mobile access points (SENMA), where the mobile access points traverse the network to collect information from individual sensors. Due to its routing simplicity and energy efficiency, SENMA has attracted lots of attention from the research community. Here, we study reliable distributed detection in SENMA under Byzantine attacks, where some authenticated sensors are compromised to report fictitious information. The q-out-of-m rule is considered. It is popular in distributed detection and can achieve a good trade-off between the miss detection probability and the false alarm rate. However, a major limitation with this rule is that the optimal scheme parameters can only be obtained through exhaustive search. By exploiting the linear relationship between the scheme parameters and the network size, we propose simple but effective sub-optimal linear approaches. Then, for better flexibility and scalability, we derive a near-optimal closed-form solution based on the central limit theorem. It is proved that the false alarm rate of the q-out-of-m scheme diminishes exponentially as the network size increases, even if the percentage of malicious nodes remains fixed. This implies that large-scale sensor networks are more reliable under malicious attacks. To further improve the performance under time varying attacks, we propose an effective malicious node detection scheme for adaptive data fusion; the proposed scheme is analyzed using the entropy-based trust model

Tactical Wireless Networking in Coalition Environments: Implementing an IEEE 802.20 Wireless End-User Network Utilizing FLASH-OFDM to Provide a Secure Mobile Extension to Existing WAN

National Research Council Canada - National Science Library

Parrish, William J; Tovar, Daniel R

2005-01-01

This thesis will focus on the area of 802.20 wireless networking as a feasible "last mile" solution to wireless access in a tactical coalition environment and will be implemented into a series of experiments...

WiMax taking wireless to the max

CERN Document Server

Pareek, Deepak

2006-01-01

With market value expected to reach 5 billion by 2007 and the endorsement of some of the biggest names in telecommunications, World Interoperability for Microwave Access (WiMAX) is poised to change the broadband wireless landscape. But how much of WiMAX's touted potential is merely hype? Now that several pre-WiMAX networks have been deployed, what are the operators saying about QoS and ROI? How and when will device manufacturers integrate WiMAX into their products? What is the business case for using WiMAX rather than any number of other established wireless alternatives?WiMAX: Taking Wireless

Enabling multimode wireless access networks using remote radio heads

DEFF Research Database (Denmark)

Kardaras, Georgios; Soler, José; Dittmann, Lars

2012-01-01

and management plane. Switching between wireless standards becomes easily feasible through firmware upgrading. Finally, real-time configuration of radio functionalities, such as transmit power, receiver gain, carrier frequency, channel bandwidth and others result in a modular software defined radio platform...

Managing healthcare information using short message service (SMS) in wireless broadband networks

Science.gov (United States)

Documet, Jorge; Tsao, Sinchai; Documet, Luis; Liu, Brent J.; Zhou, Zheng; Joseph, Anika O.

2007-03-01

Due to the ubiquity of cell phones, SMS (Short Message Service) has become an ideal means to wirelessly manage a Healthcare environment and in particular PACS (Picture Archival and Communications System) data. SMS is a flexible and mobile method for real-time access and control of Healthcare information systems such as HIS (Hospital Information System) or PACS. Unlike conventional wireless access methods, SMS' mobility is not limited by the presence of a WiFi network or any other localized signal. It provides a simple, reliable yet flexible method to communicate with an information system. In addition, SMS services are widely available for low costs from cellular phone service providers and allows for more mobility than other services such as wireless internet. This paper aims to describe a use case of SMS as a means of remotely communicating with a PACS server. Remote access to a PACS server and its Query-Retrieve services allows for a more convenient, flexible and streamlined radiology workflow. Wireless access methods such as SMS will increase dedicated PACS workstation availability for more specialized DICOM (Digital Imaging and Communications in Medicine) workflow management. This implementation will address potential security, performance and cost issues of applying SMS as part of a healthcare information management system. This is in an effort to design a wireless communication system with optimal mobility and flexibility at minimum material and time costs.

A hybrid MAC protocol design for energy-efficient very-high-throughput millimeter wave, wireless sensor communication networks

Science.gov (United States)

Jian, Wei; Estevez, Claudio; Chowdhury, Arshad; Jia, Zhensheng; Wang, Jianxin; Yu, Jianguo; Chang, Gee-Kung

2010-12-01

This paper presents an energy-efficient Medium Access Control (MAC) protocol for very-high-throughput millimeter-wave (mm-wave) wireless sensor communication networks (VHT-MSCNs) based on hybrid multiple access techniques of frequency division multiplexing access (FDMA) and time division multiplexing access (TDMA). An energy-efficient Superframe for wireless sensor communication network employing directional mm-wave wireless access technologies is proposed for systems that require very high throughput, such as high definition video signals, for sensing, processing, transmitting, and actuating functions. Energy consumption modeling for each network element and comparisons among various multi-access technologies in term of power and MAC layer operations are investigated for evaluating the energy-efficient improvement of proposed MAC protocol.

A SURVEY on WIRELESS MESH NETWORKS, ROUTING METRICS and PROTOCOLS

Directory of Open Access Journals (Sweden)

Safak DURUKAN ODABASI

2013-01-01

Full Text Available Today, Internet has become an indispensable part of our daily lives. It has a growing user community in many fields from banking transactions to online entertainment. It will be very efficient for users, as the next generation internet access becomes wireless like frequently used services such as cellular phones. But for providing this, a new network is needed to be designed or an existing network must be improved as well as making changes on infrastructure. At this point, mesh network infrastructure arises and offers more sophisticated internet access with less need. The most important advantage of mesh networks is the capability of working without infrastructure. Mesh networks are an additional access technology more than being a renewed one in the next generation wireless networks called 4G. In this study, wireless mesh networks and example applications are mentioned. Base architecture and design factors are emphasized, current routing protocols that are used on wireless mesh networks and routing metrics on which these protocols are based, are explained. Finally, the performance effects of these protocols and metrics on different network topologies are referred.

Modeling Multistandard Wireless Networks in OPNET

DEFF Research Database (Denmark)

Zakrzewska, Anna; Berger, Michael Stübert; Ruepp, Sarah Renée

2011-01-01

Future wireless communication is emerging towards one heterogeneous platform. In this new environment wireless access will be provided by multiple radio technologies that are cooperating and complementing one another. The paper investigates the possibilities of developing such a multistandard sys...... system using OPNET Modeler. A network model consisting of LTE interworking with WLAN and WiMAX is considered from the radio resource management perspective. In particular, implementing a joint packet scheduler across multiple systems is discussed more in detail....

Mobile Robot Positioning with 433-MHz Wireless Motes with Varying Transmission Powers and a Particle Filter.

Science.gov (United States)

Canedo-Rodriguez, Adrian; Rodriguez, Jose Manuel; Alvarez-Santos, Victor; Iglesias, Roberto; Regueiro, Carlos V

2015-04-30

In wireless positioning systems, the transmitter's power is usually fixed. In this paper, we explore the use of varying transmission powers to increase the performance of a wireless localization system. To this extent, we have designed a robot positioning system based on wireless motes. Our motes use an inexpensive, low-power sub-1-GHz system-on-chip (CC1110) working in the 433-MHz ISM band. Our localization algorithm is based on a particle filter and infers the robot position by: (1) comparing the power received with the expected one; and (2) integrating the robot displacement. We demonstrate that the use of transmitters that vary their transmission power over time improves the performance of the wireless positioning system significantly, with respect to a system that uses fixed power transmitters. This opens the door for applications where the robot can localize itself actively by requesting the transmitters to change their power in real time.

Mobile Robot Positioning with 433-MHz Wireless Motes with Varying Transmission Powers and a Particle Filter

Directory of Open Access Journals (Sweden)

Adrian Canedo-Rodriguez

2015-04-01

Full Text Available In wireless positioning systems, the transmitter’s power is usually fixed. In this paper, we explore the use of varying transmission powers to increase the performance of a wireless localization system. To this extent, we have designed a robot positioning system based on wireless motes. Our motes use an inexpensive, low-power sub-1-GHz system-on-chip (CC1110 working in the 433-MHz ISM band. Our localization algorithm is based on a particle filter and infers the robot position by: (1 comparing the power received with the expected one; and (2 integrating the robot displacement. We demonstrate that the use of transmitters that vary their transmission power over time improves the performance of the wireless positioning system significantly, with respect to a system that uses fixed power transmitters. This opens the door for applications where the robot can localize itself actively by requesting the transmitters to change their power in real time.

Wireless technology for ABC Assessment

DEFF Research Database (Denmark)

Kristensen, Margit; Kyng, Morten; Christensen, Erika Frischknecht

are developing: A wireless biomonitoring system (WBMS), where data, collected from (injured) persons is distributed wirelessly to displays, available for any rescuer in need of accessing the data, independently of the rescuers location. A biosensor for measuring respiration sound and frequency, to give direct....... Firstly in the daily EMS work where the collected data can be available at the hospital before the victim arrives and data can be used in the before-arrival-planning process. Secondly in larger incidents with several victims where a WBMS can support rescuers at the incident site in the assessment...

Wireless Augmented Reality Communication System

Science.gov (United States)

Devereaux, Ann (Inventor); Jedrey, Thomas (Inventor); Agan, Martin (Inventor)

2017-01-01

A portable unit is for video communication to select a user name in a user name network. A transceiver wirelessly accesses a communication network through a wireless connection to a general purpose node coupled to the communication network. A user interface can receive user input to log on to a user name network through the communication network. The user name network has a plurality of user names, at least one of the plurality of user names is associated with a remote portable unit, logged on to the user name network and available for video communication.

Digital signal processing for wireless communication using Matlab

CERN Document Server

Gopi, E S

2016-01-01

This book examines signal processing techniques used in wireless communication illustrated by using the Matlab program. The author discusses these techniques as they relate to Doppler spread; delay spread; Rayleigh and Rician channel modeling; rake receiver; diversity techniques; MIMO and OFDM -based transmission techniques; and array signal processing. Related topics such as detection theory, link budget, multiple access techniques, and spread spectrum are also covered.   ·         Illustrates signal processing techniques involved in wireless communication using Matlab ·         Discusses multiple access techniques such as Frequency division multiple access, Time division multiple access, and Code division multiple access ·         Covers band pass modulation techniques such as Binary phase shift keying, Differential phase shift keying, Quadrature phase shift keying, Binary frequency shift keying, Minimum shift keying, and Gaussian minimum shift keying.

Use of a wireless local area network in an orthodontic clinic.

Science.gov (United States)

Mupparapu, Muralidhar; Binder, Robert E; Cummins, John M

2005-06-01

Radiographic images and other patient records, including medical histories, demographics, and health insurance information, can now be stored digitally and accessed via patient management programs. However, digital image acquisition and diagnosis and treatment planning are independent tasks, and each is time consuming, especially when performed at different computer workstations. Networking or linking the computers in an office enhances access to imaging and treatment planning tools. Access can be further enhanced if the entire network is wireless. Thanks to wireless technology, stand-alone, desk-bound personal computers have been replaced with mobile, hand-held devices that can communicate with each other and the rest of the world via the Internet. As with any emerging technology, some issues should be kept in mind when adapting to the wireless environment. Foremost is network security. Second is the choice of mobile hardware devices that are used by the orthodontist, office staff, and patients. This article details the standards and choices in wireless technology that can be implemented in an orthodontic clinic and suggests how to select suitable mobile hardware for accessing or adding data to a preexisting network. The network security protocols discussed comply with HIPAA regulations and boost the efficiency of a modern orthodontic clinic.

Access Point Security Service for wireless ad-hoc communication

NARCIS (Netherlands)

Scholten, Johan; Nijdam, M.

2006-01-01

This paper describes the design and implementation of a security solution for ad-hoc peer-to-peer communication. The security solution is based on a scenario where two wireless devices require secure communication, but share no security relationship a priori. The necessary requirements for the

A Fair Contention Access Scheme for Low-Priority Traffic in Wireless Body Area Networks

Directory of Open Access Journals (Sweden)

Shagufta Henna

2017-08-01

Full Text Available Recently, wireless body area networks (WBANs have attracted significant consideration in ubiquitous healthcare. A number of medium access control (MAC protocols, primarily derived from the superframe structure of the IEEE 802.15.4, have been proposed in literature. These MAC protocols aim to provide quality of service (QoS by prioritizing different traffic types in WBANs. A contention access period (CAPwith high contention in priority-based MAC protocols can result in higher number of collisions and retransmissions. During CAP, traffic classes with higher priority are dominant over low-priority traffic; this has led to starvation of low-priority traffic, thus adversely affecting WBAN throughput, delay, and energy consumption. Hence, this paper proposes a traffic-adaptive priority-based superframe structure that is able to reduce contention in the CAP period, and provides a fair chance for low-priority traffic. Simulation results in ns-3 demonstrate that the proposed MAC protocol, called traffic- adaptive priority-based MAC (TAP-MAC, achieves low energy consumption, high throughput, and low latency compared to the IEEE 802.15.4 standard, and the most recent priority-based MAC protocol, called priority-based MAC protocol (PA-MAC.

Use of consumer wireless devices by South Africans with severe communication disability

Directory of Open Access Journals (Sweden)

Juan Bornman

2016-02-01

Full Text Available Background: Advancements in wireless technology (e.g. cell phones and tablets have opened new communication opportunities and environments for individuals with severe communication disabilities. The advancement of these technologies poses challenges to ensuring that these individuals enjoy equal access to this increasingly essential technology. However, a paucity of research exists. Objectives: To describe the nature and frequency with which South African adults with severe communication disabilities have access to and use wireless devices, as well as the types of activities for which wireless devices are used. Method: Survey research was conducted with 30 individuals who use augmentative and alternative communication (AAC technology using the Survey of User Needs Questionnaire developed in the United States, and localized to the South African context. Results: All participants, despite their limited education, unemployment and low economic status, owned and/or used mainstream wireless devices. Slightly more than half of the participants (53.3% needed adaptations to their wireless devices. Advantages of using wireless devices were highlighted, including connecting with others (through using text messaging, social networking, making plans with others, sharing photos and videos with friends, for leisure activities (e.g. listening to music, watching videos, playing games, and for safety purposes (e.g. to navigate when lost, using the device when in trouble and needing immediate assistance. Conclusion: These wireless devices offer substantial benefits and opportunities to individuals with disabilities who rely on AAC in terms of independence, social participation, education and safety/security. However, they still do not enjoy equal opportunity to access and use wireless devices relative to the non-disabled population.

A Comparison of Mobile and Fixed Device Access on User Engagement Associated With Women, Infants, and Children (WIC) Online Nutrition Education.

Science.gov (United States)

Brusk, John J; Bensley, Robert J

2016-11-15

Online health education has expanded its reach due to cost-effective implementation and demonstrated effectiveness. However, a limitation exists with the evaluation of online health education implementations and how the impact of the system is attenuated by the extent to which a user engages with it. Moreover, the current online health education research does not consider how this engagement has been affected by the transition from fixed to mobile user access over the last decade. This paper focuses on comparing the impact mobile versus fixed devices have on user engagement key performance indicators (KPI) associated with the wichealth website (.org), an Internet-based parent-child feeding intervention offered to clients associated with the US Department of Agriculture's Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Data were collected from 612,201 nutrition education lessons completed by 305,735 unique WIC participants in 21 states over a 1-year period. Data consisted of system-collected measures, profile items, and items from an exit survey administered at the conclusion of each lesson. User engagement was defined based on 3 KPIs associated with usage of the wichealth website: number of link views, link view time, and progression in stage of readiness to change. Independent samples t tests were used to compare KPIs between fixed only and mobile only device users and paired samples t tests were used to compare KPIs within users who completed at least one lesson each on both a fixed and mobile device. A logistic regression was performed to estimate the odds of KPI performance thresholds in the independent samples study group given access device type while controlling for confounding of user characteristics associated with these KPIs. Analysis of 8 user characteristics (lessons completed, race, ethnicity, language, state of residence, pregnancy status, beginning stage of change, and preferred nutrition education method) were

Towards Effective Intra-flow Network Coding in Software Defined Wireless Mesh Networks

OpenAIRE

Donghai Zhu; Xinyu Yang Yang; Peng Zhao; Wei Yu

2016-01-01

Wireless Mesh Networks (WMNs) have potential to provide convenient broadband wireless Internet access to mobile users.With the support of Software-Defined Networking (SDN) paradigm that separates control plane and data plane, WMNs can be easily deployed and managed. In addition, by exploiting the broadcast nature of the wireless medium and the spatial diversity of multi-hop wireless networks, intra-flow network coding has shown a greater benefit in comparison with traditional routing paradigm...

Revisiting of Channel Access Mechanisms in Mobile Wireless Networks through Exploiting Physical Layer Technologies

Directory of Open Access Journals (Sweden)

Junmei Yao

2018-01-01

Full Text Available The wireless local area networks (WLANs have been widely deployed with the rapid development of mobile devices and have further been brought into new applications with infrastructure mobility due to the growth of unmanned aerial vehicles (UAVs. However, the WLANs still face persistent challenge on increasing the network throughput to meet the customer’s requirement and fight against the node mobility. Interference is a well-known issue that would degrade the network performance due to the broadcast characteristics of the wireless signals. Moreover, with infrastructure mobility, the interference becomes the key obstacle in pursuing the channel capacity. Legacy interference management mechanism through the channel access control in the MAC layer design of the 802.11 standard has some well-known drawbacks, such as exposed and hidden terminal problems, inefficient rate adaptation, and retransmission schemes, making the efficient interference management an everlasting research topic over the years. Recently, interference management through exploiting physical layer mechanisms has attracted much research interest and has been proven to be a promising way to improve the network throughput, especially under the infrastructure mobility scenarios which provides more indicators for node dynamics. In this paper, we introduce a series of representative physical layer techniques and analyze how they are exploited for interference management to improve the network performance. We also provide some discussions about the research challenges and give potential future research topics in this area.

The Audacity of Fiber-Wireless (FiWi) Networks

Science.gov (United States)

Maier, Martin; Ghazisaidi, Navid; Reisslein, Martin

A plethora of enabling optical and wireless technologies have been emerging that can be used to build future-proof bimodal fiber-wireless (FiWi) broadband access networks. After overviewing key enabling radio-over-fiber (RoF) and radio-and-fiber (R&F) technologies and briefly surveying the state of the art of FiWi networks, we introduce an Ethernet-based access-metro FiWi network, called SuperMAN, that integrates next-generation WiFi and WiMAX networks with WDM-enhanced EPON and RPR networks. Throughout the paper we pay close attention to the technical challenges and opportunities of FiWi networks, but also elaborate on their societal benefits and potential to shift the current research focus from optical-wireless networking to the exploitation of personal and in-home computing facilities to create new unforeseen services and applications as we are about to enter the Petabyte age.

Virtual Lab for Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

PICOVICI, D.

2008-06-01

Full Text Available This article details an experimental system developed to enhance the education and research in the area of wireless networks technologies. The system referred, as Virtual Lab (VL is primarily targeting first time users or users with limited experience in programming and using wireless sensor networks. The VL enables a set of predefined sensor networks to be remotely accessible and controlled for constructive and time-efficient experimentation. In order to facilitate the user's wireless sensor applications, the VL is using three main components: a a Virtual Lab Motes (VLM, representing the wireless sensor, b a Virtual Lab Client (VLC, representing the user's tool to interact with the VLM and c a Virtual Lab Server (VLS representing the software link between the VLM and VLC. The concept has been proven using the moteiv produced Tmote Sky modules. Initial experimental use clearly demonstrates that the VL approach reduces dramatically the learning curve involved in programming and using the associated wireless sensor nodes. In addition the VL allows the user's focus to be directed towards the experiment and not towards the software programming challenges.

The art of wireless sensor networks

CERN Document Server

2014-01-01

During the last one and a half decades, wireless sensor networks have witnessed significant growth and tremendous development in both academia and industry.   “The Art of Wireless Sensor Networks: Volume 1: Fundamentals” focuses on the fundamentals concepts in the design, analysis, and implementation of wireless sensor networks. It covers the various layers of the lifecycle of this type of network from the physical layer up to the application layer. Its rationale is that the first volume covers contemporary design issues, tools, and protocols for radio-based two-dimensional terrestrial sensor networks. All the book chapters in this volume include up-to-date research work spanning various classic facets of the physical properties and functional behavior of wireless sensor networks, including physical layer, medium access control, data routing, topology management, mobility management, localization, task management, data management, data gathering, security, middleware, sensor technology, standards, and ...

Route Instruction Mechanism for Mobile Users Leveraging Distributed Wireless Resources

Science.gov (United States)

Kakehi, Takeshi; Shinkuma, Ryoichi; Murase, Tutomu; Motoyoshi, Gen; Yamori, Kyoko; Takahashi, Tatsuro

The market growths of smart-phones and thin clients have been significantly increasing communication traffic in mobile networks. To handle the increased traffic, network operators should consider how to leverage distributed wireless resources such as distributed spots of wireless local access networks. In this paper, we consider the system where multiple moving users share distributed wireless access points on their traveling routes between their start and goal points and formulate as an optimization problem. Then, we come up with three algorithms as a solution for the problem. The key idea here is ‘longcut route instruction’, in which users are instructed to choose a traveling route where less congested access points are available; even if the moving distance increases, the throughput for users in the system would improve. In this paper, we define the gain function. Moreover, we analyze the basic characteristics of the system using as a simple model as possible.

A Game Theoretic Framework for Bandwidth Allocation and Pricing in Federated Wireless Networks

Science.gov (United States)

Gu, Bo; Yamori, Kyoko; Xu, Sugang; Tanaka, Yoshiaki

With the proliferation of IEEE 802.11 wireless local area networks, large numbers of wireless access points have been deployed, and it is often the case that a user can detect several access points simultaneously in dense metropolitan areas. Most owners, however, encrypt their networks to prevent the public from accessing them due to the increased traffic and security risk. In this work, we use pricing as an incentive mechanism to motivate the owners to share their networks with the public, while at the same time satisfying users' service demand. Specifically, we propose a “federated network” concept, in which radio resources of various wireless local area networks are managed together. Our algorithm identifies two candidate access points with the lowest price being offered (if available) to each user. We then model the price announcements of access points as a game, and characterize the Nash Equilibrium of the system. The efficiency of the Nash Equilibrium solution is evaluated via simulation studies as well.

Convergence of Photonics and Electronics for Terahertz Wireless Communications

DEFF Research Database (Denmark)

Salazar, Adrian Ruiz; Rommel, Simon; Anufriyev, E.

2016-01-01

Terahertz wireless communications are expected to offer the required high capacity and low latency performance necessary for short-range wireless access and control applications. We present an overview of some the activities in this area in the newly started H2020 ITN project CELTA: Convergence o...... of Electronics and Photonics Technologies Enabling Terahertz Applications....

OCP: Opportunistic Carrier Prediction for Wireless Networks

Science.gov (United States)

2008-08-01

Many protocols have been proposed for medium access control in wireless networks. MACA [13], MACAW [3], and FAMA [8] are the earlier proposals for...world performance of carrier sense. In Proceedings of ACM SIGCOMM E-WIND Workshop, 2005. [13] P. Karn. MACA : A new channel access method for packet radio

DWDM Fiber-Wireless Access System with Centralized Optical Frequency Comb-based RF Carrier Generation

DEFF Research Database (Denmark)

Pang, Xiaodan; Beltrán, Marta; Sánchez, José

2013-01-01

We propose and experimentally demonstrate an optical wireless DWDM system at 60 GHz with optical incoherent heterodyne up-conversion using an optical frequency comb. Multiple users with wireline and wireless services are simultaneously supported....

Mobile agents affect worm spreading in wireless ad hoc networks

International Nuclear Information System (INIS)

Huang, Zi-Gang; Sun, Jin-Tu; Wang, Ying-Hai; Wang, Sheng-Jun; Xu, Xin-Jian

2009-01-01

Considering the dynamic nature of portable computing devices with wireless communication capability, an extended model is introduced for worm spreading in the wireless ad hoc network, with a population of mobile agents in a planar distribution, starting from an initial infected seed. The effect of agents' mobility on worm spreading is investigated via extensive Monte Carlo simulations. The threshold behavior and the dynamics of worm epidemics in the wireless networks are greatly affected by both agents' mobility and spatial and temporal correlations. The medium access control mechanism for the wireless communication promotes the sensitivity of the spreading dynamics to agents' mobility

Wireless LAN security management with location detection capability in hospitals.

Science.gov (United States)

Tanaka, K; Atarashi, H; Yamaguchi, I; Watanabe, H; Yamamoto, R; Ohe, K

2012-01-01

In medical institutions, unauthorized access points and terminals obstruct the stable operation of a large-scale wireless local area network (LAN) system. By establishing a real-time monitoring method to detect such unauthorized wireless devices, we can improve the efficiency of security management. We detected unauthorized wireless devices by using a centralized wireless LAN system and a location detection system at 370 access points at the University of Tokyo Hospital. By storing the detected radio signal strength and location information in a database, we evaluated the risk level from the detection history. We also evaluated the location detection performance in our hospital ward using Wi-Fi tags. The presence of electric waves outside the hospital and those emitted from portable game machines with wireless communication capability was confirmed from the detection result. The location detection performance showed an error margin of approximately 4 m in detection accuracy and approximately 5% in false detection. Therefore, it was effective to consider the radio signal strength as both an index of likelihood at the detection location and an index for the level of risk. We determined the location of wireless devices with high accuracy by filtering the detection results on the basis of radio signal strength and detection history. Results of this study showed that it would be effective to use the developed location database containing radio signal strength and detection history for security management of wireless LAN systems and more general-purpose location detection applications.

A Model for QoS – Aware Wireless Communication in Hospitals

Science.gov (United States)

Alavikia, Zahra; Khadivi, Pejman; Hashemi, Masoud Reza

2012-01-01

In the recent decade, research regarding wireless applications in electronic health (e-Health) services has been increasing. The main benefits of using wireless technologies in e-Health applications are simple communications, fast delivery of medical information, reducing treatment cost and also reducing the medical workers’ error rate. However, using wireless communications in sensitive healthcare environment raises electromagnetic interference (EMI). One of the most effective methods to avoid the EMI problem is power management. To this end, some of methods have been proposed in the literature to reduce EMI effects in health care environments. However, using these methods may result in nonaccurate interference avoidance and also may increase network complexity. To overcome these problems, we introduce two approaches based on per-user location and hospital sectoring for power management in sensitive healthcare environments. Although reducing transmission power could avoid EMI, it causes a number of successful message deliveries to the access point to decrease and, hence, the quality of service requirements cannot be meet. In this paper, we propose the use of relays for decreasing the probability of outage in the aforementioned scenario. Relay placement is the main factor to enjoy the usefulness of relay station benefits in the network and, therefore, we use the genetic algorithm to compute the optimum positions of a fixed number of relays. We have considered delay and maximum blind point coverage as two main criteria in relay station problem. The performance of the proposed method in outage reduction is investigated through simulations. PMID:23493832

Regressive Prediction Approach to Vertical Handover in Fourth Generation Wireless Networks

Directory of Open Access Journals (Sweden)

Abubakar M. Miyim

2014-11-01

Full Text Available The over increasing demand for deployment of wireless access networks has made wireless mobile devices to face so many challenges in choosing the best suitable network from a set of available access networks. Some of the weighty issues in 4G wireless networks are fastness and seamlessness in handover process. This paper therefore, proposes a handover technique based on movement prediction in wireless mobile (WiMAX and LTE-A environment. The technique enables the system to predict signal quality between the UE and Radio Base Stations (RBS/Access Points (APs in two different networks. Prediction is achieved by employing the Markov Decision Process Model (MDPM where the movement of the UE is dynamically estimated and averaged to keep track of the signal strength of mobile users. With the help of the prediction, layer-3 handover activities are able to occur prior to layer-2 handover, and therefore, total handover latency can be reduced. The performances of various handover approaches influenced by different metrics (mobility velocities were evaluated. The results presented demonstrate good accuracy the proposed method was able to achieve in predicting the next signal level by reducing the total handover latency.

Wireless networking for the dental office: current wireless standards and security protocols.

Science.gov (United States)

Mupparapu, Muralidhar; Arora, Sarika

2004-11-15

Digital radiography has gained immense popularity in dentistry today in spite of the early difficulty for the profession to embrace the technology. The transition from film to digital has been happening at a faster pace in the fields of Orthodontics, Oral Surgery, Endodontics, Periodontics, and other specialties where the radiographic images (periapical, bitewing, panoramic, cephalometric, and skull radiographs) are being acquired digitally, stored within a server locally, and eventually accessed for diagnostic purposes, along with the rest of the patient data via the patient management software (PMS). A review of the literature shows the diagnostic performance of digital radiography is at least comparable to or even better than that of conventional radiography. Similarly, other digital diagnostic tools like caries detectors, cephalometric analysis software, and digital scanners were used for many years for the diagnosis and treatment planning purposes. The introduction of wireless charged-coupled device (CCD) sensors in early 2004 (Schick Technologies, Long Island City, NY) has moved digital radiography a step further into the wireless era. As with any emerging technology, there are concerns that should be looked into before adapting to the wireless environment. Foremost is the network security involved in the installation and usage of these wireless networks. This article deals with the existing standards and choices in wireless technologies that are available for implementation within a contemporary dental office. The network security protocols that protect the patient data and boost the efficiency of modern day dental clinics are enumerated.

Orthogonal frequency division multiple access fundamentals and applications

CERN Document Server

Jiang, Tao; Zhang, Yan

2010-01-01

Supported by the expert-level advice of pioneering researchers, Orthogonal Frequency Division Multiple Access Fundamentals and Applications provides a comprehensive and accessible introduction to the foundations and applications of one of the most promising access technologies for current and future wireless networks. It includes authoritative coverage of the history, fundamental principles, key techniques, and critical design issues of OFDM systems. Covering various techniques of effective resource management for OFDM/OFDMA-based wireless communication systems, this cutting-edge reference:Add

Toward Wireless Health Monitoring via an Analog Signal Compression-Based Biosensing Platform.

Science.gov (United States)

Zhao, Xueyuan; Sadhu, Vidyasagar; Le, Tuan; Pompili, Dario; Javanmard, Mehdi

2018-06-01

Wireless all-analog biosensor design for the concurrent microfluidic and physiological signal monitoring is presented in this paper. The key component is an all-analog circuit capable of compressing two analog sources into one analog signal by the analog joint source-channel coding (AJSCC). Two circuit designs are discussed, including the stacked-voltage-controlled voltage source (VCVS) design with the fixed number of levels, and an improved design, which supports a flexible number of AJSCC levels. Experimental results are presented on the wireless biosensor prototype, composed of printed circuit board realizations of the stacked-VCVS design. Furthermore, circuit simulation and wireless link simulation results are presented on the improved design. Results indicate that the proposed wireless biosensor is well suited for sensing two biological signals simultaneously with high accuracy, and can be applied to a wide variety of low-power and low-cost wireless continuous health monitoring applications.

Topology and routing optimization for congestion minimization in optical wireless networks

NARCIS (Netherlands)

Ouveysi, I.; Shu, F.; Chen, W.; Shen, G.; Zukerman, M.

2010-01-01

Optical wireless networks have appealing features such as very high broadband data rates and cost effectiveness. They represent a potential alternative to the last mile (first mile) wireless access problem. However, they are also highly vulnerable to external disturbances such as adverse weather and

Combined centralised and distributed mechanism for utilisation of node association in broadband wireless network

Science.gov (United States)

Ulvan, A.; Ulvan, M.; Pranoto, H.

2018-02-01

Mobile broadband wireless access system has the stations that might be fixed, nomadic or mobile. Regarding the mobility, the node association procedure is critical for network entry as well as network re-entry during handover. The flexibility and utilisation of MAC protocols scheduling have an important role. The standard provides the Partition Scheme as the scheduling mechanism which separates the allocation of minislots for scheduling. However, minislots cannot be flexibly reserved for centralised and distributed scheduling. In this paper we analysed the scheduling mechanism to improve the utilisation of minislots allocation during the exchange of MAC massages. The centralised and distributed scheduling is implemented in some topology scenarios. The result shows the proposed mechanism has better performance for node association than partition scheme.

Protocol design and analysis for cooperative wireless networks

CERN Document Server

Song, Wei; Jin, A-Long

2017-01-01

This book focuses on the design and analysis of protocols for cooperative wireless networks, especially at the medium access control (MAC) layer and for crosslayer design between the MAC layer and the physical layer. It highlights two main points that are often neglected in other books: energy-efficiency and spatial random distribution of wireless devices. Effective methods in stochastic geometry for the design and analysis of wireless networks are also explored. After providing a comprehensive review of existing studies in the literature, the authors point out the challenges that are worth further investigation. Then, they introduce several novel solutions for cooperative wireless network protocols that reduce energy consumption and address spatial random distribution of wireless nodes. For each solution, the book offers a clear system model and problem formulation, details of the proposed cooperative schemes, comprehensive performance analysis, and extensive numerical and simulation results that validate th...

3D-Printed Disposable Wireless Sensors with Integrated Microelectronics for Large Area Environmental Monitoring

KAUST Repository

Farooqui, Muhammad Fahad

2017-05-19

Large area environmental monitoring can play a crucial role in dealing with crisis situations. However, it is challenging as implementing a fixed sensor network infrastructure over large remote area is economically unfeasible. This work proposes disposable, compact, dispersible 3D-printed wireless sensor nodes with integrated microelectronics which can be dispersed in the environment and work in conjunction with few fixed nodes for large area monitoring applications. As a proof of concept, the wireless sensing of temperature, humidity, and H2S levels are shown which are important for two critical environmental conditions namely forest fires and industrial leaks. These inkjet-printed sensors and an antenna are realized on the walls of a 3D-printed cubic package which encloses the microelectronics developed on a 3D-printed circuit board. Hence, 3D printing and inkjet printing are uniquely combined in order to realize a low-cost, fully integrated wireless sensor node.

Wireless Sensor Network for Indoor Air Quality Monitoring

Directory of Open Access Journals (Sweden)

Jun Li

2014-06-01

Full Text Available Indoor air quality monitoring system consists of wireless sensor device, nRF24L01 wireless transceiver modules, C8051MCU, STM32103 remote monitoring platform, alarm device and data server. Distributed in the interior space of wireless sensors measure parameters of the local air quality, wireless transceiver module of the MCU to transmit data to the remote monitoring platform for analysis which displayed and stored field environment data or charts. The data collecting from wireless sensors to be send by wireless Access Point to the remote data server based on B/S architecture, intelligent terminals such as mobile phone, laptop, tablet PC on the Internet monitor indoor air quality in real-time. When site environment air quality index data exceeds the threshold in the monitoring device, the remote monitoring platform sends out the alarm SMS signal to inform user by GSM module. Indoor air quality monitoring system uses modular design method, has the portability and scalability has the low manufacture cost, real-time monitoring data and man-machine interaction.

LiFi: transforming fibre into wireless

Science.gov (United States)

Yin, Liang; Islim, Mohamed Sufyan; Haas, Harald

2017-01-01

Light-fidelity (LiFi) uses energy-efficient light-emitting diodes (LEDs) for high-speed wireless communication, and it has a great potential to be integrated with fibre communication for future gigabit networks. However, by making fibre communication wireless, multiuser interference arises. Traditional methods use orthogonal multiple access (OMA) for interference avoidance. In this paper, multiuser interference is exploited with the use of non-orthogonal multiple access (NOMA) relying on successive interference cancellation (SIC). The residual interference due to imperfect SIC in practical scenarios is characterized with a proportional model. Results show that NOMA offers 5 -10 dB gain on the equivalent signal-to-interference-plus-noise ratio (SINR) over OMA. The bit error rate (BER) performance of direct current optical orthogonal frequency division multiplexing (DCO-OFDM) is shown to be significantly improved when SIC is used.

Sharing your urban residential WiFi (UR-WiFi)

NARCIS (Netherlands)

Kawade, Santosh; van Bloem, J.W.H.; Abhayawardhana, V.S.; Wisely, D.

2006-01-01

Cheap and ubiquitous broadband wireless access is what most of the operators are aiming for. This paper analyses an innovative proposal to extend the traditional fixed coverage offered by residential broadband into an urban wireless coverage using urban residential wireless fidelity (UR-WiFi)

160 Gbit/s photonics wireless transmission in the 300-500 GHz band

DEFF Research Database (Denmark)

Yu, Xianbin; Jia, S.; Hu, Hao

2016-01-01

To accommodate the ever increasing wireless traffic in the access networks, considerable efforts have been recently invested in developing photonics-assisted wireless communication systems with very high data rates. Superior to photonic millimeter-wave systems, terahertz (THz) band (300 GHz-10 THz...

How 5G Wireless (and Concomitant Technologies Will Revolutionize Healthcare?

Directory of Open Access Journals (Sweden)

Siddique Latif

2017-12-01

Full Text Available The need to have equitable access to quality healthcare is enshrined in the United Nations (UN Sustainable Development Goals (SDGs, which defines the developmental agenda of the UN for the next 15 years. In particular, the third SDG focuses on the need to “ensure healthy lives and promote well-being for all at all ages”. In this paper, we build the case that 5G wireless technology, along with concomitant emerging technologies (such as IoT, big data, artificial intelligence and machine learning, will transform global healthcare systems in the near future. Our optimism around 5G-enabled healthcare stems from a confluence of significant technical pushes that are already at play: apart from the availability of high-throughput low-latency wireless connectivity, other significant factors include the democratization of computing through cloud computing; the democratization of Artificial Intelligence (AI and cognitive computing (e.g., IBM Watson; and the commoditization of data through crowdsourcing and digital exhaust. These technologies together can finally crack a dysfunctional healthcare system that has largely been impervious to technological innovations. We highlight the persistent deficiencies of the current healthcare system and then demonstrate how the 5G-enabled healthcare revolution can fix these deficiencies. We also highlight open technical research challenges, and potential pitfalls, that may hinder the development of such a 5G-enabled health revolution.

SDN Based User-Centric Framework for Heterogeneous Wireless Networks

Directory of Open Access Journals (Sweden)

Zhaoming Lu

2016-01-01

Full Text Available Due to the rapid growth of mobile data traffic, more and more basestations and access points (APs have been densely deployed to provide users with ubiquitous network access, which make current wireless network a complex heterogeneous network (HetNet. However, traditional wireless networks are designed with network-centric approaches where different networks have different quality of service (QoS strategies and cannot easily cooperate with each other to serve network users. Massive network infrastructures could not assure users perceived network and service quality, which is an indisputable fact. To address this issue, we design a new framework for heterogeneous wireless networks with the principle of user-centricity, refactoring the network from users’ perspective to suffice their requirements and preferences. Different from network-centric approaches, the proposed framework takes advantage of Software Defined Networking (SDN and virtualization technology, which will bring better perceived services quality for wireless network users. In the proposed user-centric framework, control plane and data plane are decoupled to manage the HetNets in a flexible and coadjutant way, and resource virtualization technology is introduced to abstract physical resources of HetNets into unified virtualized resources. Hence, ubiquitous and undifferentiated network connectivity and QoE (quality of experience driven fine-grained resource management could be achieved for wireless network users.

Resource and Traffic Management Techniques for Performance Optimization in Wireless Mesh Networks

OpenAIRE

D'Elia, Francesco Paolo

2010-01-01

Since Internet was born, it has steadily evolved. New devices, new needs, new applications, new protocols, and this evolution is not going to slow down in the near future. As a result of the introduction and standardization of wireless access technology, we are living through an inevitable replacement of the old wired technology. We are going through a wireless revolution, which brings with it new ways to access information: simply, anywhere, anytime. The new Internet challenge is to embo...

Medium access control and network layer design for 60 GHz wireless personal area networks

NARCIS (Netherlands)

An, X.

2010-01-01

The unlicensed frequency band around 60 GHz is a very promising spectrum due to its potential to provide multiple gigabits per second based data rates for short range wireless communication. Hence, 60 GHz radio is an attractive candidate to enable ultra high rate Wireless Personal Area Networks

Portable wireless power transmission system for video capsule endoscopy.

Science.gov (United States)

Zhiwei, Jia; Guozheng, Yan; Bingquan, Zhu

2014-10-01

Wireless power transmission is considered a practical way of overcoming the power shortage of wireless capsule endoscopy (VCE). However, most patients cannot tolerate the long hours of lying in a fixed transmitting coil during diagnosis. To develop a portable wireless power transmission system for VCE, a compact transmitting coil and a portable inverter circuit driven by rechargeable batteries are proposed. The couple coils, optimized considering the stability and safety conditions, are 28 turns of transmitting coil and six strands of receiving coil. The driven circuit is designed according to the portable principle. Experiments show that the integrated system could continuously supply power to a dual-head VCE for more than 8 h at a frame rate of 30 frames per second with resolution of 320 × 240. The portable VCE exhibits potential for clinical applications, but requires further improvement and tests.

Detection of Spoofed MAC Addresses in 802.11 Wireless Networks

Science.gov (United States)

Tao, Kai; Li, Jing; Sampalli, Srinivas

Medium Access Control (MAC) address spoofing is considered as an important first step in a hacker's attempt to launch a variety of attacks on 802.11 wireless networks. Unfortunately, MAC address spoofing is hard to detect. Most current spoofing detection systems mainly use the sequence number (SN) tracking technique, which has drawbacks. Firstly, it may lead to an increase in the number of false positives. Secondly, such techniques cannot be used in systems with wireless cards that do not follow standard 802.11 sequence number patterns. Thirdly, attackers can forge sequence numbers, thereby causing the attacks to go undetected. We present a new architecture called WISE GUARD (Wireless Security Guard) for detection of MAC address spoofing on 802.11 wireless LANs. It integrates three detection techniques - SN tracking, Operating System (OS) fingerprinting & tracking and Received Signal Strength (RSS) fingerprinting & tracking. It also includes the fingerprinting of Access Point (AP) parameters as an extension to the OS fingerprinting for detection of AP address spoofing. We have implemented WISE GUARD on a test bed using off-the-shelf wireless devices and open source drivers. Experimental results show that the new design enhances the detection effectiveness and reduces the number of false positives in comparison with current approaches.

Mobile access to the Internet: from personal bubble to satellites

Science.gov (United States)

Gerla, Mario

2001-10-01

Mobile, wireless access and networking has emerged in the last few years as one of the most important directions of Internet growth. The popularity of mobile, and, more generally, nomadic Internet access is due to many enabling factors including: (a) emergence of meaningful applications tailored to the individual on the move; (b) small form factor and long battery life; (c) efficient middleware designed to support mobility; and, (d) efficient wireless networking technologies. A key player in the mobile Internet access is the nomad, i.e. the individual equipped with various computing and I/O gadgets (cellular phone, earphones, GPS navigator, palm pilot, beeper, portable scanner, digital camera, etc.). These devices form his/her Personal Area Network or PAN or personal bubble. The connectivity within the bubble is wireless (using for example a low cost, low power wireless LAN such as Bluetooth). The bubble can expand and contract dynamically depending on needs. It may temporarily include sensors and actuators as the nomad walks into a new environment. In this paper, we identify the need for the interconnection of the PAN with other wireless networks in order to achieve costeffective mobile access to the Internet. We will overview some key networking technologies required to support the PAN (eg, Bluetooth). We will also discuss an emerging technology, Ad Hoc wireless networking which is the natural complement of the PAN in sparsely populated areas. Finally, we will identify the need for intelligent routers to assist the mobile user in the selection of the best Internet access strategy.

Wireless Cellular Mobile Communications

Directory of Open Access Journals (Sweden)

V. Zalud

2002-12-01

Full Text Available In this article is briefly reviewed the history of wireless cellularmobile communications, examined the progress in current secondgeneration (2G cellular standards and discussed their migration to thethird generation (3G. The European 2G cellular standard GSM and itsevolution phases GPRS and EDGE are described somewhat in detail. Thethird generation standard UMTS taking up on GSM/GPRS core network andequipped with a new advanced access network on the basis of codedivision multiple access (CDMA is investigated too. A sketch of theperspective of mobile communication beyond 3G concludes this article.

A wireless computational platform for distributed computing based traffic monitoring involving mixed Eulerian-Lagrangian sensing

KAUST Repository

Jiang, Jiming

2013-06-01

This paper presents a new wireless platform designed for an integrated traffic monitoring system based on combined Lagrangian (mobile) and Eulerian (fixed) sensing. The sensor platform is built around a 32-bit ARM Cortex M4 micro-controller and a 2.4GHz 802.15.4 ISM compliant radio module, and can be interfaced with fixed traffic sensors, or receive data from vehicle transponders. The platform is specially designed and optimized to be integrated in a solar-powered wireless sensor network in which traffic flow maps are computed by the nodes directly using distributed computing. A MPPT circuitry is proposed to increase the power output of the attached solar panel. A self-recovering unit is designed to increase reliability and allow periodic hard resets, an essential requirement for sensor networks. A radio monitoring circuitry is proposed to monitor incoming and outgoing transmissions, simplifying software debug. An ongoing implementation is briefly discussed, and compared with existing platforms used in wireless sensor networks. © 2013 IEEE.

An Efficient Radio Access Control Mechanism for Wireless Network-On-Chip Architectures

Directory of Open Access Journals (Sweden)

Maurizio Palesi

2015-03-01

Full Text Available Modern systems-on-chip (SoCs today contain hundreds of cores, and this number is predicted to reach the thousands by the year 2020. As the number of communicating elements increases, there is a need for an efficient, scalable and reliable communication infrastructure. As technology geometries shrink to the deep submicron regime, however, the communication delay and power consumption of global interconnections become the major bottleneck. The network-on-chip (NoC design paradigm, based on a modular packet-switched mechanism, can address many of the on-chip communication issues, such as the performance limitations of long interconnects and integration of large number of cores on a chip. Recently, new communication technologies based on the NoC concept have emerged with the aim of improving the scalability limitations of conventional NoC-based architectures. Among them, wireless NoCs (WiNoCs use the radio medium for reducing the performance and energy penalties of long-range and multi-hop communications. As the radio medium can be accessed by a single transmitter at a time, a radio access control mechanism (RACM is needed. In this paper, we present a novel RACM, which allows one to improve both the performance and energy figures of the WiNoC. Experiments, carried out on both synthetic and real traffic scenarios, have shown the effectiveness of the proposed RACM. On average, a 30% reduction in communication delay and a 25% energy savings have been observed when the proposed RACM is applied to a known WiNoC architecture.

Cyber Insurance for Heterogeneous Wireless Networks

OpenAIRE

Lu, Xiao; Niyato, Dusit; Jiang, Hai; Wang, Ping; Poor, H. Vincent

2017-01-01

Heterogeneous wireless networks (HWNs) composed of densely deployed base stations of different types with various radio access technologies have become a prevailing trend to accommodate ever-increasing traffic demand in enormous volume. Nowadays, users rely heavily on HWNs for ubiquitous network access that contains valuable and critical information such as financial transactions, e-health, and public safety. Cyber risks, representing one of the most significant threats to network security an...

A Framework for Planning a Unified Wired and Wireless ICT Infrastructure

DEFF Research Database (Denmark)

Riaz, M. Tahir; Nielsen, Rasmus Hjorth; Pedersen, Jens Myrup

The increase in the use of information and communication technology (ICT) has pushed the existing access networks to their limits. Whole new access networks are currently being deployed and are expected to take full advantage of the already started synergy of services converging on to one network....... Through a brief survey of synergy and technology trends, it is concluded that a future network will complementary use of wired and wireless technologies. In this context the paper proposes a framework for planning of unified wired and wireless ICT infrastructures. The framework includes different input...

A Framework for Planning a Unified Wired and Wireless ICT Infrastructure

DEFF Research Database (Denmark)

Riaz, M. Tahir; Nielsen, Rasmus Hjorth; Pedersen, Jens Myrup

2010-01-01

The increase in the use of information and communication technology (ICT) has pushed the existing access networks to their limits. Whole new access networks are currently being deployed and are expected to fully support the already started synergy of services converging on to one network. Through...... a brief survey of synergy and technology trends, it is concluded that a future network will use wired and wireless as complementary technologies. In this context the paper proposes a framework for planning of unified wired and wireless ICT infrastructures. The framework includes different input parameters...

New ergonomic headset for Tongue-Drive System with wireless smartphone interface.

Science.gov (United States)

Park, Hangue; Kim, Jeonghee; Huo, Xueliang; Hwang, In-O; Ghovanloo, Maysam

2011-01-01

Tongue Drive System (TDS) is a wireless tongue-operated assistive technology (AT), developed for people with severe physical disabilities to control their environment using their tongue motion. We have developed a new ergonomic headset for the TDS with a user-friendly smartphone interface, through which users will be able to wirelessly control various devices, access computers, and drive wheelchairs. This headset design is expected to act as a flexible and multifunctional communication interface for the TDS and improve its usability, accessibility, aesthetics, and convenience for the end users.

Isochronous wireless network for real-time communication in industrial automation

CERN Document Server

Trsek, Henning

2016-01-01

This dissertation proposes and investigates an isochronous wireless network for industrial control applications with guaranteed latencies and jitter. Based on a requirements analysis of real industrial applications and the characterisation of the wireless channel, the solution approach is developed. It consists of a TDMA-based medium access control, a dynamic resource allocation and the provision of a global time base for the wired and the wireless network. Due to the global time base, the solution approach allows a seamless and synchronous integration into existing wired Real-time Ethernet systems.

Impact of fixed-mobile convergence

DEFF Research Database (Denmark)

Pachnicke, Stephan; Andrus, Bogdan-Mihai; Autenrieth, Achim

2016-01-01

Fixed-Mobile Convergence (FMC) is a very trendy concept as it promises integration of the previously separated fixed access network and the mobile network. From this novel approach telecommunication operators expect significant cost savings and performance improvements. FMC can be separated...

Energy efficient medium access protocol for wireless medical body area sensor networks.

Science.gov (United States)

Omeni, O; Wong, A; Burdett, A J; Toumazou, C

2008-12-01

This paper presents a novel energy-efficient MAC Protocol designed specifically for wireless body area sensor networks (WBASN) focused towards pervasive healthcare applications. Wireless body area networks consist of wireless sensor nodes attached to the human body to monitor vital signs such as body temperature, activity or heart-rate. The network adopts a master-slave architecture, where the body-worn slave node periodically sends sensor readings to a central master node. Unlike traditional peer-to-peer wireless sensor networks, the nodes in this biomedical WBASN are not deployed in an ad hoc fashion. Joining a network is centrally managed and all communications are single-hop. To reduce energy consumption, all the sensor nodes are in standby or sleep mode until the centrally assigned time slot. Once a node has joined a network, there is no possibility of collision within a cluster as all communication is initiated by the central node and is addressed uniquely to a slave node. To avoid collisions with nearby transmitters, a clear channel assessment algorithm based on standard listen-before-transmit (LBT) is used. To handle time slot overlaps, the novel concept of a wakeup fallback time is introduced. Using single-hop communication and centrally controlled sleep/wakeup times leads to significant energy reductions for this application compared to more ldquoflexiblerdquo network MAC protocols such as 802.11 or Zigbee. As duty cycle is reduced, the overall power consumption approaches the standby power. The protocol is implemented in hardware as part of the Sensiumtrade system-on-chip WBASN ASIC, in a 0.13- mum CMOS process.

Dynamic Contention Window Control Scheme in IEEE 802.11e EDCA-Based Wireless LANs

Science.gov (United States)

Abeysekera, B. A. Hirantha Sithira; Matsuda, Takahiro; Takine, Tetsuya

In the IEEE 802.11 MAC protocol, access points (APs) are given the same priority as wireless terminals in terms of acquiring the wireless link, even though they aggregate several downlink flows. This feature leads to a serious throughput degradation of downlink flows, compared with uplink flows. In this paper, we propose a dynamic contention window control scheme for the IEEE 802.11e EDCA-based wireless LANs, in order to achieve fairness between uplink and downlink TCP flows while guaranteeing QoS requirements for real-time traffic. The proposed scheme first determines the minimum contention window size in the best-effort access category at APs, based on the number of TCP flows. It then determines the minimum and maximum contention window sizes in higher priority access categories, such as voice and video, so as to guarantee QoS requirements for these real-time traffic. Note that the proposed scheme does not require any modification to the MAC protocol at wireless terminals. Through simulation experiments, we show the effectiveness of the proposed scheme.

Adaptive Information Access on Multiple Applications Support Wireless Sensor Networks

DEFF Research Database (Denmark)

Tobgay, Sonam; Olsen, Rasmus Løvenstein; Prasad, Ramjee

2014-01-01

information is challenged by dynamic nature of information elements. These challenges are more prominent in case of wireless sensor network (WSN) applications, as the information that the sensor node collects are mostly dynamic in nature (say, temperature). Therefore, it is likely that there can be a mismatch...

Adaptive Information Access in Multiple Applications Support Wireless Sensor Network

DEFF Research Database (Denmark)

Tobgay, Sonam; Olsen, Rasmus Løvenstein; Prasad, Ramjee

2012-01-01

Nowadays, due to wide applicability of Wireless Sensor Network (WSN) added by the low cost sensor devices, its popularity among the researchers and industrialists are very much visible. A substantial amount of works can be seen in the literature on WSN which are mainly focused on application...

Resilient Disaster Network Based on Software Defined Cognitive Wireless Network Technology

Directory of Open Access Journals (Sweden)

Goshi Sato

2015-01-01

Full Text Available In order to temporally recover the information network infrastructure in disaster areas from the Great East Japan Earthquake in 2011, various wireless network technologies such as satellite IP network, 3G, and Wi-Fi were effectively used. However, since those wireless networks are individually introduced and installed but not totally integrated, some of networks were congested due to the sudden network traffic generation and unbalanced traffic distribution, and eventually the total network could not effectively function. In this paper, we propose a disaster resilient network which integrates various wireless networks into a cognitive wireless network that users can use as an access network to the Internet at the serious disaster occurrence. We designed and developed the disaster resilient network based on software defined network (SDN technology to automatically select the best network link and route among the possible access networks to the Internet by periodically monitoring their network states and evaluate those using extended AHP method. In order to verify the usefulness of our proposed system, a prototype system is constructed and its performance is evaluated.

Verification of electromagnetic effects from wireless devices in operating nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Ye, Song Hae; Kim, Young Sik; Lyou, Ho Sun; Kim, Min Suk [Korea Hydro and Nuclear Power Co. (KHNP), Central Research Institute, Daejeon (Korea, Republic of); Lyou, Joon [Dept. of Electronics Engineering, Chungnam National University, Daejeon (Korea, Republic of)

2015-10-15

Wireless communication technologies, especially smart phones, have become increasingly common. Wireless technology is widely used in general industry and this trend is also expected to grow with the development of wireless technology. However, wireless technology is not currently applied in any domestic operating nuclear power plants (NPPs) because of the highest priority of the safety policy. Wireless technology is required in operating NPPs, however, in order to improve the emergency responses and work efficiency of the operators and maintenance personnel during its operation. The wired telephone network in domestic NPPs can be simply connected to a wireless local area network to use wireless devices. This design change can improve the ability of the operators and personnel to respond to an emergency situation by using important equipment for a safe shutdown. IEEE 802.11 smart phones (Wi-Fi standard), Internet Protocol (IP) phones, personal digital assistant (PDA) for field work, notebooks used with web cameras, and remote site monitoring tablet PCs for on-site testing may be considered as wireless devices that can be used in domestic operating NPPs. Despite its advantages, wireless technology has only been used during the overhaul period in Korean NPPs due to the electromagnetic influence of sensitive equipment and cyber security problems. This paper presents the electromagnetic verification results from major sensitive equipment after using wireless devices in domestic operating NPPs. It also provides a solution for electromagnetic interference/radio frequency interference (EMI/RFI) from portable and fixed wireless devices with a Wi-Fi communication environment within domestic NPPs.

Verification of electromagnetic effects from wireless devices in operating nuclear power plants

Directory of Open Access Journals (Sweden)

Song-Hae Ye

2015-10-01

Full Text Available Wireless communication technologies, especially smartphones, have become increasingly common. Wireless technology is widely used in general industry and this trend is also expected to grow with the development of wireless technology. However, wireless technology is not currently applied in any domestic operating nuclear power plants (NPPs because of the highest priority of the safety policy. Wireless technology is required in operating NPPs, however, in order to improve the emergency responses and work efficiency of the operators and maintenance personnel during its operation. The wired telephone network in domestic NPPs can be simply connected to a wireless local area network to use wireless devices. This design change can improve the ability of the operators and personnel to respond to an emergency situation by using important equipment for a safe shutdown. IEEE 802.11 smartphones (Wi-Fi standard, Internet Protocol (IP phones, personal digital assistant (PDA for field work, notebooks used with web cameras, and remote site monitoring tablet PCs for on-site testing may be considered as wireless devices that can be used in domestic operating NPPs. Despite its advantages, wireless technology has only been used during the overhaul period in Korean NPPs due to the electromagnetic influence of sensitive equipment and cyber security problems. This paper presents the electromagnetic verification results from major sensitive equipment after using wireless devices in domestic operating NPPs. It also provides a solution for electromagnetic interference/radio frequency interference (EMI/RFI from portable and fixed wireless devices with a Wi-Fi communication environment within domestic NPPs.

Verification of electromagnetic effects from wireless devices in operating nuclear power plants

International Nuclear Information System (INIS)

Ye, Song Hae; Kim, Young Sik; Lyou, Ho Sun; Kim, Min Suk; Lyou, Joon

2015-01-01

Wireless communication technologies, especially smart phones, have become increasingly common. Wireless technology is widely used in general industry and this trend is also expected to grow with the development of wireless technology. However, wireless technology is not currently applied in any domestic operating nuclear power plants (NPPs) because of the highest priority of the safety policy. Wireless technology is required in operating NPPs, however, in order to improve the emergency responses and work efficiency of the operators and maintenance personnel during its operation. The wired telephone network in domestic NPPs can be simply connected to a wireless local area network to use wireless devices. This design change can improve the ability of the operators and personnel to respond to an emergency situation by using important equipment for a safe shutdown. IEEE 802.11 smart phones (Wi-Fi standard), Internet Protocol (IP) phones, personal digital assistant (PDA) for field work, notebooks used with web cameras, and remote site monitoring tablet PCs for on-site testing may be considered as wireless devices that can be used in domestic operating NPPs. Despite its advantages, wireless technology has only been used during the overhaul period in Korean NPPs due to the electromagnetic influence of sensitive equipment and cyber security problems. This paper presents the electromagnetic verification results from major sensitive equipment after using wireless devices in domestic operating NPPs. It also provides a solution for electromagnetic interference/radio frequency interference (EMI/RFI) from portable and fixed wireless devices with a Wi-Fi communication environment within domestic NPPs

Analisa Pengaruh Tarif Dan Kualitas Terhadap Voluntary Churn Produk Flexi Trendy (Studi Kasus : PT. Telkom Wilayah Kota Semarang )

OpenAIRE

Santoso, Haryo; Saptadi, Singgih; Benita, Benita

2010-01-01

At twenty first century, telecommunication has being developed rapidly. It has been proven by technologies appearance in the telecommunication sector which facilitates people to communicate each to another. There are two kinds of wireless telecommunication service that has been known in Indonesia, Full Mobility telecommunication service or Mobile Wireless Access (MWA) and Limited Mobility or Fixed Wireless Access (FWA). While, the used technology are consist of GSM (Global System for Mobile C...

Wireless "Questions-Bank" System to Enhance M-Learning in School Education

Directory of Open Access Journals (Sweden)

Samir Abou El-Seoud

2010-01-01

Full Text Available Abstract: Through wireless devices and wireless applications, M-learning supports an integrated access to Web content and services in education anytime and anywhere. This paper describes the analysis, design, and implementation of "Wireless Questions-Bank System", that allows the students to take web-based quizzes, web-based free exercises, web-based exams (midterm, and final, to download course reviews, to download previous exams and their model answers, to access the system through the Mobile and take quick quizzes and exercises. The system facilitates generation of automatic, balanced, and different exam sheets, that containing different types of questions, covering the entire curriculum, and displaying gradually from easiness to difficulty. The exam sheet produced by the system, takes into account the different levels of the students from excellent, good, to fair, and avoids any mistakes of language and non-clear terminologies

KeyWare: an open wireless distributed computing environment

Science.gov (United States)

Shpantzer, Isaac; Schoenfeld, Larry; Grindahl, Merv; Kelman, Vladimir

1995-12-01

Deployment of distributed applications in the wireless domain lack equivalent tools, methodologies, architectures, and network management that exist in LAN based applications. A wireless distributed computing environment (KeyWareTM) based on intelligent agents within a multiple client multiple server scheme was developed to resolve this problem. KeyWare renders concurrent application services to wireline and wireless client nodes encapsulated in multiple paradigms such as message delivery, database access, e-mail, and file transfer. These services and paradigms are optimized to cope with temporal and spatial radio coverage, high latency, limited throughput and transmission costs. A unified network management paradigm for both wireless and wireline facilitates seamless extensions of LAN- based management tools to include wireless nodes. A set of object oriented tools and methodologies enables direct asynchronous invocation of agent-based services supplemented by tool-sets matched to supported KeyWare paradigms. The open architecture embodiment of KeyWare enables a wide selection of client node computing platforms, operating systems, transport protocols, radio modems and infrastructures while maintaining application portability.

M2M massive wireless access

DEFF Research Database (Denmark)

Zanella, Andrea; Zorzi, Michele; Santos, André F.

2013-01-01

In order to make the Internet of Things a reality, ubiquitous coverage and low-complexity connectivity are required. Cellular networks are hence the most straightforward and realistic solution to enable a massive deployment of always connected Machines around the globe. Nevertheless, a paradigm...... shift in the conception and design of future cellular networks is called for. Massive access attempts, low-complexity and cheap machines, sporadic transmission and correlated signals are among the main properties of this new reality, whose main consequence is the disruption of the development...... Access Reservation, Coded Random Access and the exploitation of multiuser detection in random access. Additionally, we will show how the properties of machine originated signals, such as sparsity and spatial/time correlation can be exploited. The end goal of this paper is to provide motivation...

Seamless and secure communications over heterogeneous wireless networks

CERN Document Server

Cao, Jiannong

2014-01-01

This brief provides an overview of the requirements, challenges, design issues and major techniques for seamless and secure communications over heterogeneous wireless networks. It summarizes and provides detailed insights into the latest research on handoff management, mobility management, fast authentication and security management to support seamless and secure roaming for mobile clients. The reader will also learn about the challenges in developing relevant technologies and providing ubiquitous Internet access over heterogeneous wireless networks. The authors have extensive experience in im

Anticipating WPS PIN Vulnerability to Secure Wireless Network

Directory of Open Access Journals (Sweden)

Indra Dwi Rianto

2013-12-01

Full Text Available WiFi Protected Setup (WPS is a standardized function supported by numerous vendors of wireless routers and access point to help set up connection to a wireless local area network. It is designed to simplify the set up and generally enabled by default. Due to design flaw, the WPS or QSS PIN is susceptible to a brute forceattack. In this paper, we test the security vulnerability occurred, evaluate the performance and give recommendations to anticipate the attack.

The wireless networking system of Earthquake precursor mobile field observation

Science.gov (United States)

Wang, C.; Teng, Y.; Wang, X.; Fan, X.; Wang, X.

2012-12-01

The mobile field observation network could be real-time, reliably record and transmit large amounts of data, strengthen the physical signal observations in specific regions and specific period, it can improve the monitoring capacity and abnormal tracking capability. According to the features of scatter everywhere, a large number of current earthquake precursor observation measuring points, networking technology is based on wireless broadband accessing McWILL system, the communication system of earthquake precursor mobile field observation would real-time, reliably transmit large amounts of data to the monitoring center from measuring points through the connection about equipment and wireless accessing system, broadband wireless access system and precursor mobile observation management center system, thereby implementing remote instrument monitoring and data transmition. At present, the earthquake precursor field mobile observation network technology has been applied to fluxgate magnetometer array geomagnetic observations of Tianzhu, Xichang,and Xinjiang, it can be real-time monitoring the working status of the observational instruments of large area laid after the last two or three years, large scale field operation. Therefore, it can get geomagnetic field data of the local refinement regions and provide high-quality observational data for impending earthquake tracking forecast. Although, wireless networking technology is very suitable for mobile field observation with the features of simple, flexible networking etc, it also has the phenomenon of packet loss etc when transmitting a large number of observational data due to the wireless relatively weak signal and narrow bandwidth. In view of high sampling rate instruments, this project uses data compression and effectively solves the problem of data transmission packet loss; Control commands, status data and observational data transmission use different priorities and means, which control the packet loss rate within

DESIGN OF CAUCUS MEDIUM ACCESS CONTROL (C-MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS IN SMART GRIDS

Directory of Open Access Journals (Sweden)

JEETU SHARMA

2017-10-01

Full Text Available A Caucus-based medium access control protocol (C-MAC is proposed to reduce the end to end delay and battery consumption of the sensor nodes deployed in the monitoring of various smart grid regions, such as substation, pole and wires, perimeter security, real time and non-real-time monitoring using wireless sensor networks. The objective is to prolong the network lifetime and to reduce the end to end delay by mitigating the energy-hole problem and by eliminating bottlenecks significantly by using caucus based efficient synchronization techniques in multi-hop square grid topology of the wireless sensor networks (WSNs. The protocol self-reliantly and adaptively schedules node’s wake-up times, decreases idle listening and collisions, increases network throughput, and extends network lifetime. It induces a low duty cycle for adjusting wake-up times of sensor nodes. The appropriate selection of active and sleep time slots and next hop relay nodes are proposed to minimize the data transmission latency and to reduce battery consumption to increase the network lifetime. The uniform and synchronized transmission of the data packets is of prime importance to improve the network performance. Simulation results justify that the proposed C-MAC protocol increases the network lifetime, successful data transmission ratio along-with the reduction in end to end delay. The objective of this paper is to envisage benefits and utilization of C-MAC protocol for WSNs deployed in smart grids and to draw the attention of researchers in this area.

Towards a Versatile Problem Diagnosis Infrastructure for LargeWireless Sensor Networks

NARCIS (Netherlands)

Iwanicki, Konrad; Steen, van Maarten

2007-01-01

In this position paper, we address the issue of durable maintenance of a wireless sensor network, which will be crucial if the vision of large, long-lived sensornets is to become reality. Durable maintenance requires tools for diagnosing and fixing occurring problems, which can range from

Fixed-Rate Compressed Floating-Point Arrays.

Science.gov (United States)

Lindstrom, Peter

2014-12-01

Current compression schemes for floating-point data commonly take fixed-precision values and compress them to a variable-length bit stream, complicating memory management and random access. We present a fixed-rate, near-lossless compression scheme that maps small blocks of 4(d) values in d dimensions to a fixed, user-specified number of bits per block, thereby allowing read and write random access to compressed floating-point data at block granularity. Our approach is inspired by fixed-rate texture compression methods widely adopted in graphics hardware, but has been tailored to the high dynamic range and precision demands of scientific applications. Our compressor is based on a new, lifted, orthogonal block transform and embedded coding, allowing each per-block bit stream to be truncated at any point if desired, thus facilitating bit rate selection using a single compression scheme. To avoid compression or decompression upon every data access, we employ a software write-back cache of uncompressed blocks. Our compressor has been designed with computational simplicity and speed in mind to allow for the possibility of a hardware implementation, and uses only a small number of fixed-point arithmetic operations per compressed value. We demonstrate the viability and benefits of lossy compression in several applications, including visualization, quantitative data analysis, and numerical simulation.

Effect Through Broadcasting System Access Point For Video Transmission

Directory of Open Access Journals (Sweden)

Leni Marlina

2015-08-01

Full Text Available Most universities are already implementing wired and wireless network that is used to access integrated information systems and the Internet. At present it is important to do research on the influence of the broadcasting system through the access point for video transmitter learning in the university area. At every university computer network through the access point must also use the cable in its implementation. These networks require cables that will connect and transmit data from one computer to another computer. While wireless networks of computers connected through radio waves. This research will be a test or assessment of how the influence of the network using the WLAN access point for video broadcasting means learning from the server to the client. Instructional video broadcasting from the server to the client via the access point will be used for video broadcasting means of learning. This study aims to understand how to build a wireless network by using an access point. It also builds a computer server as instructional videos supporting software that can be used for video server that will be emitted by broadcasting via the access point and establish a system of transmitting video from the server to the client via the access point.

Wireless technologies for closed-loop retinal prostheses

Science.gov (United States)

Ng, David C.; Bai, Shun; Yang, Jiawei; Tran, Nhan; Skafidas, Efstratios

2009-12-01

In this paper, we discuss various technologies needed to develop retinal prostheses with wireless power and data telemetry operation. In addition to the need to communicate with the implanted device, supply of power to the retinal prosthesis is especially difficult. This is because, in the implanted state, the device is not fixed in position due to constant motion of the eye. Furthermore, a retinal prosthesis incorporating a high density electrode array of more than 1000 electrodes is expected to consume approximately 45 mW of power and require 300 kbps of image and stimulation data. The front end of the wireless power and data transmission, the antenna, needs to be small compared to the size of the eye. Also, the wireless module is expected to operate in the reactive near-field region due to small separation between the transmit and receive antennas compared to their size and corresponding operating wavelength. An inductive link is studied as a means to transfer power and for data telemetry between the implant and external unit. In this work, the use of integrated circuit and microfabrication technologies for implementing inductive links is discussed. A closed-loop approach is taken to improve performance and reach optimum operation condition. Design and simulation data are presented as the basis for development of viable wireless module prototypes.

PDA-phone-based instant transmission of radiological images over a CDMA network by combining the PACS screen with a Bluetooth-interfaced local wireless link.

Science.gov (United States)

Kim, Dong Keun; Yoo, Sun K; Park, Jeong Jin; Kim, Sun Ho

2007-06-01

Remote teleconsultation by specialists is important for timely, correct, and specialized emergency surgical and medical decision making. In this paper, we designed a new personal digital assistant (PDA)-phone-based emergency teleradiology system by combining cellular communication with Bluetooth-interfaced local wireless links. The mobility and portability resulting from the use of PDAs and wireless communication can provide a more effective means of emergency teleconsultation without requiring the user to be limited to a fixed location. Moreover, it enables synchronized radiological image sharing between the attending physician in the emergency room and the remote specialist on picture archiving and communication system terminals without distorted image acquisition. To enable rapid and fine-quality radiological image transmission over a cellular network in a secure manner, progressive compression and security mechanisms have been incorporated. The proposed system is tested over a code division Multiple Access 1x-Evolution Data-Only network to evaluate the performance and to demonstrate the feasibility of this system in a real-world setting.

An orthogonal wavelet division multiple-access processor architecture for LTE-advanced wireless/radio-over-fiber systems over heterogeneous networks

Science.gov (United States)

Mahapatra, Chinmaya; Leung, Victor CM; Stouraitis, Thanos

2014-12-01

The increase in internet traffic, number of users, and availability of mobile devices poses a challenge to wireless technologies. In long-term evolution (LTE) advanced system, heterogeneous networks (HetNet) using centralized coordinated multipoint (CoMP) transmitting radio over optical fibers (LTE A-ROF) have provided a feasible way of satisfying user demands. In this paper, an orthogonal wavelet division multiple-access (OWDMA) processor architecture is proposed, which is shown to be better suited to LTE advanced systems as compared to orthogonal frequency division multiple access (OFDMA) as in LTE systems 3GPP rel.8 (3GPP, http://www.3gpp.org/DynaReport/36300.htm). ROF systems are a viable alternative to satisfy large data demands; hence, the performance in ROF systems is also evaluated. To validate the architecture, the circuit is designed and synthesized on a Xilinx vertex-6 field-programmable gate array (FPGA). The synthesis results show that the circuit performs with a clock period as short as 7.036 ns (i.e., a maximum clock frequency of 142.13 MHz) for transform size of 512. A pipelined version of the architecture reduces the power consumption by approximately 89%. We compare our architecture with similar available architectures for resource utilization and timing and provide performance comparison with OFDMA systems for various quality metrics of communication systems. The OWDMA architecture is found to perform better than OFDMA for bit error rate (BER) performance versus signal-to-noise ratio (SNR) in wireless channel as well as ROF media. It also gives higher throughput and mitigates the bad effect of peak-to-average-power ratio (PAPR).

Energy-efficient data collection in wireless sensor networks with time constraints

NARCIS (Netherlands)

Mitici, M.A.; Goseling, Jasper; de Graaf, Maurits; Boucherie, Richardus J.

We consider the problem of retrieving a reliable estimate of an attribute from a wireless sensor network within a fixed time window and with minimum energy consumption for the sensors. The sensors are located in the plane according to some random spatial process. They perform energy harvesting and

Open-Source tools: Incidence in the wireless security of the Technical University of Babahoyo

Directory of Open Access Journals (Sweden)

Joffre León-Acurio

2018-02-01

Full Text Available Computer security is a fundamental part of an organization, especially in Higher Education institutions, where there is very sensitive information, capable of being vulnerable by diffeerent methods of intrusion, the most common being free access through wireless points. The main objective of this research is to analyze the impact of the open source tools in charge of managing the security information of the wireless network, such as OSSIM, a set of active and passive components used to manage events that generate tra c within the network. net. This research exposes the use of free software as a viable option of low cost to solve the problems that a ict student sta , such as lack of access to academic services, problems of wireless interconnectivity, with the purpose to restore confidence in students in the Use of the services offered by the institution for research-related development, guaranteeing free and free access to the internet. The level of dissatisfaction on the part of the students con rms the problem presented at the Technical University of Babahoyo, thus confirming the positive influence of the Open-Source tools for the institution’s wireless security.

Secure Your Wireless Network: Going Wireless Comes with Its Own Special Set of Security Concerns

Science.gov (United States)

Bloomquist, Jane; Musa, Atif

2004-01-01

Imagine a completely wireless school, an open network in which all students and staff can roam around using laptops or handheld computers to browse the Internet, access files and applications on the school server, and communicate with each other and the world via e-mail. It's a great picture--and at some schools the future is already here. But…

Energy-Efficiency Analysis of a Distributed Queuing Medium Access Control Protocol for Biomedical Wireless Sensor Networks in Saturation Conditions

Directory of Open Access Journals (Sweden)

Christos Verikoukis

2011-01-01

Full Text Available The aging population and the high quality of life expectations in our society lead to the need of more efficient and affordable healthcare solutions. For this reason, this paper aims for the optimization of Medium Access Control (MAC protocols for biomedical wireless sensor networks or wireless Body Sensor Networks (BSNs. The hereby presented schemes always have in mind the efficient management of channel resources and the overall minimization of sensors’ energy consumption in order to prolong sensors’ battery life. The fact that the IEEE 802.15.4 MAC does not fully satisfy BSN requirements highlights the need for the design of new scalable MAC solutions, which guarantee low-power consumption to the maximum number of body sensors in high density areas (i.e., in saturation conditions. In order to emphasize IEEE 802.15.4 MAC limitations, this article presents a detailed overview of this de facto standard for Wireless Sensor Networks (WSNs, which serves as a link for the introduction and initial description of our here proposed Distributed Queuing (DQ MAC protocol for BSN scenarios. Within this framework, an extensive DQ MAC energy-consumption analysis in saturation conditions is presented to be able to evaluate its performance in relation to IEEE 802.5.4 MAC in highly dense BSNs. The obtained results show that the proposed scheme outperforms IEEE 802.15.4 MAC in average energy consumption per information bit, thus providing a better overall performance that scales appropriately to BSNs under high traffic conditions. These benefits are obtained by eliminating back-off periods and collisions in data packet transmissions, while minimizing the control overhead.

Resource management for multimedia services in high data rate wireless networks

CERN Document Server

Zhang, Ruonan; Pan, Jianping

2017-01-01

This brief offers a valuable resource on principles of quality-of-service (QoS) provisioning and the related link-layer resource management techniques for high data-rate wireless networks. The primary emphasis is on protocol modeling and analysis. It introduces media access control (MAC) protocols, standards of wireless local area networks (WLANs), wireless personal area networks (WPANs), and wireless body area networks (WBANs), discussing their key technologies, applications, and deployment scenarios. The main analytical approaches and models for performance analysis of the fundamental resource scheduling mechanisms, including the contention-based, reservation-based, and hybrid MAC, are presented. To help readers understand and evaluate system performance, the brief contains a range of simulation results. In addition, a thorough bibliography provides an additional tool. This brief is an essential resource for engineers, researchers, students, and users of wireless networks.

Hands-On Open Access Broadband Wireless Technology Lab Mapping Course Outcomes to Lab Experiments

Directory of Open Access Journals (Sweden)

Yazan Alqudah

2012-10-01

Full Text Available The unprecedented growth in wireless communication is offering opportunities and challenges for educators. Thanks to technology advances and job opportunities, more and more students are interested in wireless communications courses. However, bridging the gap between classroom and real-world experience remains a challenge. Advanced undergraduate communications courses typically focus more on theory. Some courses are given online, and lack hands-on experiments. Driven by feedback from industry and students, we propose practical laboratory experiments that attempt to bridge the gap between classroom and real world. The laboratory exercises take advantage of the infrastructure of deployed wireless networks and allow students to measure, and analyze data, as well as to interact. The proposed labs can be used even in online courses. This paper describes the experiments proposed, the procedures and typical results. The experiments are tied to course objective.

Towards Controlling Latency in Wireless Networks

KAUST Repository

Bouacida, Nader

2017-04-24

Wireless networks are undergoing an unprecedented revolution in the last decade. With the explosion of delay-sensitive applications in the Internet (i.e., online gaming and VoIP), latency becomes a major issue for the development of wireless technology. Taking advantage of the significant decline in memory prices, industrialists equip the network devices with larger buffering capacities to improve the network throughput by limiting packets drops. Over-buffering results in increasing the time that packets spend in the queues and, thus, introducing more latency in networks. This phenomenon is known as “bufferbloat”. While throughput is the dominant performance metric, latency also has a huge impact on user experience not only for real-time applications but also for common applications like web browsing, which is sensitive to latencies in order of hundreds of milliseconds. Concerns have arisen about designing sophisticated queue management schemes to mitigate the effects of such phenomenon. My thesis research aims to solve bufferbloat problem in both traditional half-duplex and cutting-edge full-duplex wireless systems by reducing delay while maximizing wireless links utilization and fairness. Our work shed lights on buffer management algorithms behavior in wireless networks and their ability to reduce latency resulting from excessive queuing delays inside oversized static network buffers without a significant loss in other network metrics. First of all, we address the problem of buffer management in wireless full-duplex networks by using Wireless Queue Management (WQM), which is an active queue management technique for wireless networks. Our solution is based on Relay Full-Duplex MAC (RFD-MAC), an asynchronous media access control protocol designed for relay full-duplexing. Compared to the default case, our solution reduces the end-to-end delay by two orders of magnitude while achieving similar throughput in most of the cases. In the second part of this thesis

A wireless sensor enabled by wireless power.

Science.gov (United States)

Lee, Da-Sheng; Liu, Yu-Hong; Lin, Chii-Ruey

2012-11-22

Through harvesting energy by wireless charging and delivering data by wireless communication, this study proposes the concept of a wireless sensor enabled by wireless power (WPWS) and reports the fabrication of a prototype for functional tests. One WPWS node consists of wireless power module and sensor module with different chip-type sensors. Its main feature is the dual antenna structure. Following RFID system architecture, a power harvesting antenna was designed to gather power from a standard reader working in the 915 MHz band. Referring to the Modbus protocol, the other wireless communication antenna was integrated on a node to send sensor data in parallel. The dual antenna structure integrates both the advantages of an RFID system and a wireless sensor. Using a standard UHF RFID reader, WPWS can be enabled in a distributed area with a diameter up to 4 m. Working status is similar to that of a passive tag, except that a tag can only be queried statically, while the WPWS can send dynamic data from the sensors. The function is the same as a wireless sensor node. Different WPWSs equipped with temperature and humidity, optical and airflow velocity sensors are tested in this study. All sensors can send back detection data within 8 s. The accuracy is within 8% deviation compared with laboratory equipment. A wireless sensor network enabled by wireless power should be a totally wireless sensor network using WPWS. However, distributed WPWSs only can form a star topology, the simplest topology for constructing a sensor network. Because of shielding effects, it is difficult to apply other complex topologies. Despite this limitation, WPWS still can be used to extend sensor network applications in hazardous environments. Further research is needed to improve WPWS to realize a totally wireless sensor network.

3D-Printed Disposable Wireless Sensors with Integrated Microelectronics for Large Area Environmental Monitoring

KAUST Repository

Farooqui, Muhammad Fahad; Karimi, Muhammad Akram; Salama, Khaled N.; Shamim, Atif

2017-01-01

disposable, compact, dispersible 3D-printed wireless sensor nodes with integrated microelectronics which can be dispersed in the environment and work in conjunction with few fixed nodes for large area monitoring applications. As a proof of concept

A Uniform Voltage Gain Control for Alignment Robustness in Wireless EV Charging

Directory of Open Access Journals (Sweden)

Yabiao Gao

2015-08-01

Full Text Available The efficiency of wireless power transfer is sensitive to the horizontal and vertical distances between the transmitter and receiver coils due to the magnetic coupling change. To address the output voltage variation and efficiency drop caused by misalignment, a uniform voltage gain frequency control is implemented to improve the power delivery and efficiency of wireless power transfer under misalignment. The frequency is tuned according to the amplitude and phase-frequency characteristics of coupling variations in order to maintain a uniform output voltage in the receiver coil. Experimental comparison of three control methods, including fixed frequency control, resonant frequency control, and the proposed uniform gain control was conducted and demonstrated that the uniform voltage gain control is the most robust method for managing misalignment in wireless charging applications.

Wireless Heart Patients and the Quantified Self

DEFF Research Database (Denmark)

Grew, Julie Christina; Svendsen, Mette Nordahl

2017-01-01

Remote monitoring of implantable cardioverter defibrillator (ICD) patients links patients wirelessly to the clinic via a box in their bedroom. The box transmits data from the ICD to a remote database accessible to clinicians without patient involvement. Data travel across time and space; clinicia...

A Hybrid TDMA/CSMA-Based Wireless Sensor and Data Transmission Network for ORS Intra-Microsatellite Applications.

Science.gov (United States)

Wang, Long; Liu, Yong; Yin, Zengshan

2018-05-12

To achieve launch-on-demand for Operationally Responsive Space (ORS) missions, in this article, an intra-satellite wireless network (ISWN) is presented. It provides a wireless and modularized scheme for intra-spacecraft sensing and data buses. By removing the wired data bus, the commercial off-the-shelf (COTS) based wireless modular architecture will reduce both the volume and weight of the satellite platform, thus achieving rapid design and cost savings in development and launching. Based on the on-orbit data demand analysis, a hybrid time division multiple access/carrier sense multiple access (TDMA/CSMA) protocol is proposed. It includes an improved clear channel assessment (CCA) mechanism and a traffic adaptive slot allocation method. To analyze the access process, a Markov model is constructed. Then a detailed calculation is given in which the unsaturated cases are considered. Through simulations, the proposed protocol is proved to commendably satisfy the demands and performs better than existing schemes. It helps to build a full-wireless satellite instead of the current wired ones, and will contribute to provide dynamic space capabilities for ORS missions.

Data transmission techniques for short-range optical fiber and wireless communication links

DEFF Research Database (Denmark)

Pham, Tien Thang

The research work described in this thesis is devoted to experimental investigation of techniques for cost-effective high-speed optical communications supporting both wired and wireless services. The main contributions of this thesis have expanded the state-of-the-art in two main areas: high......-speed optical/wireless integration and advanced modulation formats for intensity modulation with direct detection (IM/DD) optical systems. Regarding optical/wireless integration, this thesis focuses on integration of broadband ultra-wide band (UWB) and 60-GHz band wireless systems into optical fiber access...... networks to distribute wireless services in personal area networks (PANs). Photonic technologies to generate and distribute gigabit UWB and 60-GHz-band signals are proposed and demonstrated. Two novel methods are proposed and demonstrated to optically generate Federal Communications Commission (FCC...

11th International Conference On Broad-Band Wireless Computing, Communication and Applications

CERN Document Server

Xhafa, Fatos; Yim, Kangbin

2017-01-01

The success of all-IP networking and wireless technology has changed the ways of living the people around the world. The progress of electronic integration and wireless communications is going to pave the way to offer people the access to the wireless networks on the fly, based on which all electronic devices will be able to exchange the information with each other in ubiquitous way whenever necessary. The aim of the volume is to provide latest research findings, innovative research results, methods and development techniques from both theoretical and practical perspectives related to the emerging areas of broadband and wireless computing. This proceedings volume presents the results of the 11th International Conference on Broad-Band Wireless Computing, Communication And Applications (BWCCA-2016), held November 5-7, 2016, at Soonchunhyang University, Asan, Korea. .

Advertisement-Based Energy Efficient Medium Access Protocols for Wireless Sensor Networks

Science.gov (United States)

Ray, Surjya Sarathi

One of the main challenges that prevents the large-scale deployment of Wireless Sensor Networks (WSNs) is providing the applications with the required quality of service (QoS) given the sensor nodes' limited energy supplies. WSNs are an important tool in supporting applications ranging from environmental and industrial monitoring, to battlefield surveillance and traffic control, among others. Most of these applications require sensors to function for long periods of time without human intervention and without battery replacement. Therefore, energy conservation is one of the main goals for protocols for WSNs. Energy conservation can be performed in different layers of the protocol stack. In particular, as the medium access control (MAC) layer can access and control the radio directly, large energy savings is possible through intelligent MAC protocol design. To maximize the network lifetime, MAC protocols for WSNs aim to minimize idle listening of the sensor nodes, packet collisions, and overhearing. Several approaches such as duty cycling and low power listening have been proposed at the MAC layer to achieve energy efficiency. In this thesis, I explore the possibility of further energy savings through the advertisement of data packets in the MAC layer. In the first part of my research, I propose Advertisement-MAC or ADV-MAC, a new MAC protocol for WSNs that utilizes the concept of advertising for data contention. This technique lets nodes listen dynamically to any desired transmission and sleep during transmissions not of interest. This minimizes the energy lost in idle listening and overhearing while maintaining an adaptive duty cycle to handle variable loads. Additionally, ADV-MAC enables energy efficient MAC-level multicasting. An analytical model for the packet delivery ratio and the energy consumption of the protocol is also proposed. The analytical model is verified with simulations and is used to choose an optimal value of the advertisement period

A Low Collision and High Throughput Data Collection Mechanism for Large-Scale Super Dense Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Chunyang Lei

2016-07-01

Full Text Available Super dense wireless sensor networks (WSNs have become popular with the development of Internet of Things (IoT, Machine-to-Machine (M2M communications and Vehicular-to-Vehicular (V2V networks. While highly-dense wireless networks provide efficient and sustainable solutions to collect precise environmental information, a new channel access scheme is needed to solve the channel collision problem caused by the large number of competing nodes accessing the channel simultaneously. In this paper, we propose a space-time random access method based on a directional data transmission strategy, by which collisions in the wireless channel are significantly decreased and channel utility efficiency is greatly enhanced. Simulation results show that our proposed method can decrease the packet loss rate to less than 2 % in large scale WSNs and in comparison with other channel access schemes for WSNs, the average network throughput can be doubled.

A Low Collision and High Throughput Data Collection Mechanism for Large-Scale Super Dense Wireless Sensor Networks.

Science.gov (United States)

Lei, Chunyang; Bie, Hongxia; Fang, Gengfa; Gaura, Elena; Brusey, James; Zhang, Xuekun; Dutkiewicz, Eryk

2016-07-18

Super dense wireless sensor networks (WSNs) have become popular with the development of Internet of Things (IoT), Machine-to-Machine (M2M) communications and Vehicular-to-Vehicular (V2V) networks. While highly-dense wireless networks provide efficient and sustainable solutions to collect precise environmental information, a new channel access scheme is needed to solve the channel collision problem caused by the large number of competing nodes accessing the channel simultaneously. In this paper, we propose a space-time random access method based on a directional data transmission strategy, by which collisions in the wireless channel are significantly decreased and channel utility efficiency is greatly enhanced. Simulation results show that our proposed method can decrease the packet loss rate to less than 2 % in large scale WSNs and in comparison with other channel access schemes for WSNs, the average network throughput can be doubled.

Directional Medium Access Control (MAC Protocols in Wireless Ad Hoc and Sensor Networks: A Survey

Directory of Open Access Journals (Sweden)

David Tung Chong Wong

2015-06-01

Full Text Available This survey paper presents the state-of-the-art directional medium access control (MAC protocols in wireless ad hoc and sensor networks (WAHSNs. The key benefits of directional antennas over omni-directional antennas are longer communication range, less multipath interference, more spatial reuse, more secure communications, higher throughput and reduced latency. However, directional antennas lead to single-/multi-channel directional hidden/exposed terminals, deafness and neighborhood, head-of-line blocking, and MAC-layer capture which need to be overcome. Addressing these problems and benefits for directional antennas to MAC protocols leads to many classes of directional MAC protocols in WAHSNs. These classes of directional MAC protocols presented in this survey paper include single-channel, multi-channel, cooperative and cognitive directional MACs. Single-channel directional MAC protocols can be classified as contention-based or non-contention-based or hybrid-based, while multi-channel directional MAC protocols commonly use a common control channel for control packets/tones and one or more data channels for directional data transmissions. Cooperative directional MAC protocols improve throughput in WAHSNs via directional multi-rate/single-relay/multiple-relay/two frequency channels/polarization, while cognitive directional MAC protocols leverage on conventional directional MAC protocols with new twists to address dynamic spectrum access. All of these directional MAC protocols are the pillars for the design of future directional MAC protocols in WAHSNs.

Joint Hybrid Backhaul and Access Links Design in Cloud-Radio Access Networks

KAUST Repository

Dhifallah, Oussama Najeeb

2015-09-06

The cloud-radio access network (CRAN) is expected to be the core network architecture for next generation mobile radio systems. In this paper, we consider the downlink of a CRAN formed of one central processor (the cloud) and several base station (BS), where each BS is connected to the cloud via either a wireless or capacity-limited wireline backhaul link. The paper addresses the joint design of the hybrid backhaul links (i.e., designing the wireline and wireless backhaul connections from the cloud to the BSs) and the access links (i.e., determining the sparse beamforming solution from the BSs to the users). The paper formulates the hybrid backhaul and access link design problem by minimizing the total network power consumption. The paper solves the problem using a two-stage heuristic algorithm. At one stage, the sparse beamforming solution is found using a weighted mixed 11/12 norm minimization approach; the correlation matrix of the quantization noise of the wireline backhaul links is computed using the classical rate-distortion theory. At the second stage, the transmit powers of the wireless backhaul links are found by solving a power minimization problem subject to quality-of-service constraints, based on the principle of conservation of rate by utilizing the rates found in the first stage. Simulation results suggest that the performance of the proposed algorithm approaches the global optimum solution, especially at high signal-to-interference-plus-noise ratio (SINR).

A wireless laser displacement sensor node for structural health monitoring.

Science.gov (United States)

Park, Hyo Seon; Kim, Jong Moon; Choi, Se Woon; Kim, Yousok

2013-09-30

This study describes a wireless laser displacement sensor node that measures displacement as a representative damage index for structural health monitoring (SHM). The proposed measurement system consists of a laser displacement sensor (LDS) and a customized wireless sensor node. Wireless communication is enabled by a sensor node that consists of a sensor module, a code division multiple access (CDMA) communication module, a processor, and a power module. An LDS with a long measurement distance is chosen to increase field applicability. For a wireless sensor node driven by a battery, we use a power control module with a low-power processor, which facilitates switching between the sleep and active modes, thus maximizing the power consumption efficiency during non-measurement and non-transfer periods. The CDMA mode is also used to overcome the limitation of communication distance, which is a challenge for wireless sensor networks and wireless communication. To evaluate the reliability and field applicability of the proposed wireless displacement measurement system, the system is tested onsite to obtain the required vertical displacement measurements during the construction of mega-trusses and an edge truss, which are the primary structural members in a large-scale irregular building currently under construction. The measurement values confirm the validity of the proposed wireless displacement measurement system and its potential for use in safety evaluations of structural elements.

A Wireless Laser Displacement Sensor Node for Structural Health Monitoring

Directory of Open Access Journals (Sweden)

Se Woon Choi

2013-09-01

Full Text Available This study describes a wireless laser displacement sensor node that measures displacement as a representative damage index for structural health monitoring (SHM. The proposed measurement system consists of a laser displacement sensor (LDS and a customized wireless sensor node. Wireless communication is enabled by a sensor node that consists of a sensor module, a code division multiple access (CDMA communication module, a processor, and a power module. An LDS with a long measurement distance is chosen to increase field applicability. For a wireless sensor node driven by a battery, we use a power control module with a low-power processor, which facilitates switching between the sleep and active modes, thus maximizing the power consumption efficiency during non-measurement and non-transfer periods. The CDMA mode is also used to overcome the limitation of communication distance, which is a challenge for wireless sensor networks and wireless communication. To evaluate the reliability and field applicability of the proposed wireless displacement measurement system, the system is tested onsite to obtain the required vertical displacement measurements during the construction of mega-trusses and an edge truss, which are the primary structural members in a large-scale irregular building currently under construction. The measurement values confirm the validity of the proposed wireless displacement measurement system and its potential for use in safety evaluations of structural elements.

An Adaptive Handover Prediction Scheme for Seamless Mobility Based Wireless Networks

Directory of Open Access Journals (Sweden)

Ali Safa Sadiq

2014-01-01

Full Text Available We propose an adaptive handover prediction (AHP scheme for seamless mobility based wireless networks. That is, the AHP scheme incorporates fuzzy logic with AP prediction process in order to lend cognitive capability to handover decision making. Selection metrics, including received signal strength, mobile node relative direction towards the access points in the vicinity, and access point load, are collected and considered inputs of the fuzzy decision making system in order to select the best preferable AP around WLANs. The obtained handover decision which is based on the calculated quality cost using fuzzy inference system is also based on adaptable coefficients instead of fixed coefficients. In other words, the mean and the standard deviation of the normalized network prediction metrics of fuzzy inference system, which are collected from available WLANs are obtained adaptively. Accordingly, they are applied as statistical information to adjust or adapt the coefficients of membership functions. In addition, we propose an adjustable weight vector concept for input metrics in order to cope with the continuous, unpredictable variation in their membership degrees. Furthermore, handover decisions are performed in each MN independently after knowing RSS, direction toward APs, and AP load. Finally, performance evaluation of the proposed scheme shows its superiority compared with representatives of the prediction approaches.

Data Access Based on a Guide Map of the Underwater Wireless Sensor Network.

Science.gov (United States)

Wei, Zhengxian; Song, Min; Yin, Guisheng; Song, Houbing; Wang, Hongbin; Ma, Xuefei; Cheng, Albert M K

2017-10-17

Underwater wireless sensor networks (UWSNs) represent an area of increasing research interest, as data storage, discovery, and query of UWSNs are always challenging issues. In this paper, a data access based on a guide map (DAGM) method is proposed for UWSNs. In DAGM, the metadata describes the abstracts of data content and the storage location. The center ring is composed of nodes according to the shortest average data query path in the network in order to store the metadata, and the data guide map organizes, diffuses and synchronizes the metadata in the center ring, providing the most time-saving and energy-efficient data query service for the user. For this method, firstly the data is stored in the UWSN. The storage node is determined, the data is transmitted from the sensor node (data generation source) to the storage node, and the metadata is generated for it. Then, the metadata is sent to the center ring node that is the nearest to the storage node and the data guide map organizes the metadata, diffusing and synchronizing it to the other center ring nodes. Finally, when there is query data in any user node, the data guide map will select a center ring node nearest to the user to process the query sentence, and based on the shortest transmission delay and lowest energy consumption, data transmission routing is generated according to the storage location abstract in the metadata. Hence, specific application data transmission from the storage node to the user is completed. The simulation results demonstrate that DAGM has advantages with respect to data access time and network energy consumption.

Development of a personal digital assistant-based wireless application in clinical practice.

Science.gov (United States)

Chen, Yen-Cheng; Chiu, Hou-Chang; Tsai, Ming-Dar; Chang, Hang; Chong, Chee-Fah

2007-02-01

Our study aims to develop a personal digital assistant (PDA)-based wireless application in medical information processing by using Bluetooth and IEEE 802.11b wireless standards and SyncML codes. In this study, an "integrated database access module" is used to provide a unified integrated access interface while consistency of wireless data transmission is achieved by using the standardized SyncML protocol. A prototype of the system has been developed, implemented, and tested for its mobility, usability, stability, and performance with questionnaire survey. Response time for browsing/searching was usually less than 3s. The average time intervals needed for data transmissions were 68.6+/-8.5s for Bluetooth and 47.0+/-4.8s for 802.11b. The five-point Likert scale (from 1=least to 5=most) questionnaire survey of 30 medical professionals yielded a high degree of satisfaction with the system's mobility (4.18+/-0.89), usability (4.69+/-0.90), stability (3.81+/-0.94), and performance (3.97+/-0.88). The results of our study suggested that PDA applications which exploit wireless communication are convenient and feasible in clinical practice.

Simplified Fiber-Wireless Distribution of HD Video in Passive and Active W-band Close Proximity Terminals

DEFF Research Database (Denmark)

Lebedev, Alexander; Rodes Lopez, Roberto; Yu, Xianbin

2012-01-01

We experimentally demonstrate uncompressed high-definition (HD) video distribution at 84 GHz Radio over Fiber link achieving up to 3 meters of wireless transmission. We experimentally emulate Metro-Access architecture by deploying single/multimode fibers. Passive and active approaches for remote...... antenna unit (RAU) are experimentally investigated. The bit error rate (BER) performance of the optical and wireless channels is reported. A successful transmission of uncompressed HD video in the W-band wireless channel is demonstrated with prospects to pave the way for application-focused fiber-wireless...

160 Gbit/s photonics wireless transmission in the 300-500 GHz band

Directory of Open Access Journals (Sweden)

X. Yu

2016-11-01

Full Text Available To accommodate the ever increasing wireless traffic in the access networks, considerable efforts have been recently invested in developing photonics-assisted wireless communication systems with very high data rates. Superior to photonic millimeter-wave systems, terahertz (THz band (300 GHz-10 THz provides a much larger bandwidth and thus promises an extremely high capacity. However, the capacity potential of THz wireless systems has by no means been achieved yet. Here, we successfully demonstrate 160 Gbit/s wireless transmission by using a single THz emitter and modulating 25 GHz spaced 8 channels (20 Gbps per channel in the 300-500 GHz band, which is the highest bitrate in the frequency band above 300 GHz, to the best of our knowledge.

Clock Synchronization for Multihop Wireless Sensor Networks

Science.gov (United States)

Solis Robles, Roberto

2009-01-01

In wireless sensor networks, more so generally than in other types of distributed systems, clock synchronization is crucial since by having this service available, several applications such as media access protocols, object tracking, or data fusion, would improve their performance. In this dissertation, we propose a set of algorithms to achieve…

TRICALCAR : Weaving Community Based Wireless Networks in ...

International Development Research Centre (IDRC) Digital Library (Canada)

... wireless champions by facilitating the exchange of knowledge between them and with other like-minded actors in the region. The training materials and knowledge gained during the experience will be documented and made available online. The idea is to improve Internet access in rural and urban marginalized areas at ...

Network performance and fault analytics for LTE wireless service providers

CERN Document Server

Kakadia, Deepak; Gilgur, Alexander

2017-01-01

 This book is intended to describe how to leverage emerging technologies big data analytics and SDN, to address challenges specific to LTE and IP network performance and fault management data in order to more efficiently manage and operate an LTE wireless networks. The proposed integrated solutions permit the LTE network service provider to operate entire integrated network, from RAN to Core , from UE to application service, as one unified system and correspondingly collect and align disparate key metrics and data, using an integrated and holistic approach to network analysis. The LTE wireless network performance and fault involves the network performance and management of network elements in EUTRAN, EPC and IP transport components, not only as individual components, but also as nuances of inter-working of these components. The key metrics for EUTRAN include radio access network accessibility, retainability, integrity, availability and mobility. The key metrics for EPC include MME accessibility, mobility and...

Interference-Aware Radio Resource Management for Local Area Wireless Networks

Directory of Open Access Journals (Sweden)

Ribeiro CássioB

2011-01-01

Full Text Available Interference-aware multiple access is an enabler to cost-efficient and reliable high data-rate local area wireless access. In this paper, we propose an interference-aware radio resource management scheme where receivers inform about their throughput, interference, and signal levels by means of broadcast messages tied to data reception. In the proposed scheme, the conventional scheduler is extended to interference-aware operation where individual scheduling decisions are based on estimated change in system-level performance. The performance of the proposed scheme is evaluated in system simulations where it is compared to a conventional scheduler and a centralized scheduler (global optimum. The convergence of the proposed scheduler is analyzed and signaling overhead of an example implementation is characterized. The results demonstrate that the proposed scheme enables fair and efficient wireless access in challenging interference scenarios, for example, multiple networks deployed in the same geographical area and sharing a common band.

Large-Scale Wireless Temperature Monitoring System for Liquefied Petroleum Gas Storage Tanks

Directory of Open Access Journals (Sweden)

Guangwen Fan

2015-09-01

Full Text Available Temperature distribution is a critical indicator of the health condition for Liquefied Petroleum Gas (LPG storage tanks. In this paper, we present a large-scale wireless temperature monitoring system to evaluate the safety of LPG storage tanks. The system includes wireless sensors networks, high temperature fiber-optic sensors, and monitoring software. Finally, a case study on real-world LPG storage tanks proves the feasibility of the system. The unique features of wireless transmission, automatic data acquisition and management, local and remote access make the developed system a good alternative for temperature monitoring of LPG storage tanks in practical applications.

Large-Scale Wireless Temperature Monitoring System for Liquefied Petroleum Gas Storage Tanks.

Science.gov (United States)

Fan, Guangwen; Shen, Yu; Hao, Xiaowei; Yuan, Zongming; Zhou, Zhi

2015-09-18

Temperature distribution is a critical indicator of the health condition for Liquefied Petroleum Gas (LPG) storage tanks. In this paper, we present a large-scale wireless temperature monitoring system to evaluate the safety of LPG storage tanks. The system includes wireless sensors networks, high temperature fiber-optic sensors, and monitoring software. Finally, a case study on real-world LPG storage tanks proves the feasibility of the system. The unique features of wireless transmission, automatic data acquisition and management, local and remote access make the developed system a good alternative for temperature monitoring of LPG storage tanks in practical applications.

Introduction to Wireless Localization With iPhone SDK Examples

CERN Document Server

Chan, Eddie C L

2012-01-01

This book provides a comprehensive overview of the entire landscape of both outdoor and indoor wireless positioning, and guides the reader step by step in the implementation of wireless positioning applications on the iPhone. Explanations of fundamental positioning techniques are given throughout the text, along with many programming examples, providing the reader with an independent, practical, and enjoyable learning of the material while gaining a real feel for the subject.  Provides an accessible introduction to positioning technologies such as Global Positioning System and Wi-Fi posi

Deployment of Wireless Sensor Networks in Crop Storages

DEFF Research Database (Denmark)

Juul, Jakob Pilegaard; Green, Ole; Jacobsen, Rune Hylsberg

2015-01-01

of a wireless sensor network based system that provides continuous, automatic, and up-to-date information on a crop storage, while presenting the data in an easily accessible manner, is also described. The design decisions, challenges, and practical experiences from real-world large scale deployment...

Convergence of photonics and electronics for Terahertz wireless communications – the ITN CELTA project

DEFF Research Database (Denmark)

Tafur Monroy, Idelfonso

2016-01-01

Terahertz wireless communications is expected to offer the required high capacity and low latency performance required from short-range wireless access and control applications. We present an overview of some the activities in this area in the newly started H2020 ITN project CELTA: convergence of...... of electronics and photonics technologies enabling Terahertz applications...

Wireless Competition in Canada: An Assessment

Directory of Open Access Journals (Sweden)

Jeffrey Church

2013-08-01

Full Text Available If there’s one thing Canadians agree on, it’s that Canada’s wireless industry can and should be more competitive. The federal government is on side with the policy objective of having four carriers in every region and has responded with policies that provide commercial advantages to entrants. But, the rub is that there has not been a study that actually assesses the state of competition in wireless services in Canada, until now. Those in favour of policies that will promote and sustain entry point to Canada’s high average revenue per user and low wireless penetration rate (mobile connections per capita as evidence that there is insufficient competition. The difficulty is that the facts are not consistent with this simplistic analysis. Measurements of wireless penetration are skewed toward countries that maintain the Calling Party Pays Protocol and favour pay-as-you-go plans, both of which encourage inflated user counts. Canada’s participation per capita on monthly plans and minutes of voice per capita are not outliers. Moreover, in terms of smartphone adoption and smartphone data usage, Canada is a global leader, contributing to high average revenue per user. Consistent with being world leaders in the rollout of high speed wireless networks, Canada lead its peer group in capital expenditures per subscriber in 2012: the competition of importance to Canadians is not just over price, but also over the quality of wireless networks. In any event, none of the measures typically used in international comparisons are relevant to assessing the competitiveness of Canadian wireless services. The appropriate competitive analysis recognizes two relevant features of the technology of wireless services: (i high fixed and sunk capital costs; and (ii economies of scale and scope. The implications of these are that profitability requires mark ups over short run measures of cost — high gross margins — and that there will be a natural, upper limit on

Fixed mobile convergence handbook

CERN Document Server

Ahson, Syed A

2010-01-01

From basic concepts to future directions, this handbook provides technical information on all aspects of fixed-mobile convergence (FMC). The book examines such topics as integrated management architecture, business trends and strategic implications for service providers, personal area networks, mobile controlled handover methods, SIP-based session mobility, and supervisory and notification aggregator service. Case studies are used to illustrate technical and systematic implementation of unified and rationalized internet access by fixed-mobile network convergence. The text examines the technolo

Convergencia de sistemas de comunicación ópticos e inalámbricos (Converged wireless and optical communication systems)

DEFF Research Database (Denmark)

Tafur Monroy, Idelfonso; Guerrero Gonzalez, Neil; Caballero Jambrina, Antonio

2009-01-01

Users of tele-information services are demanding instant access, everywhere and anytime. Wireless communication systems offers mobility and flexibility while optical fiber based systems offer large bandwidth, secure and lower power consumption for transport of tele-communication signals. None...... of the two technologies separately can satisfy the demands of user for ubiquitous and affordable access to information services. Converged optical and wireless systems offer a solution that combines the best of both technologies. This article review the trends in converged optical-wireless communication...... systems and outline the role that photonic technologies is playing in making the vision of a converged network a reality....

Reliable low-power wireless networks over unstable transmission power

NARCIS (Netherlands)

Kotian, Roshan; Exarchakos, Georgios; Liotta, Antonio

2017-01-01

Internet of Things promises large scale interconnected sensing and actuation capabilities in domains, areas, applications and activities never accessed before by Internet. Besides other technical barriers, wireless network node lifetime impedes its applicability. To reduce the energy cost incurred

Cloud based spectrum manager for future wireless regulatory environment

CSIR Research Space (South Africa)

Masonta, MT

2015-12-01

Full Text Available The regulatory environment in radio frequency spectrum management lags the advancement of wireless technologies, especially in the area of cognitive radio and dynamic spectrum access. In this paper we argue that the solution towards spectrum Pareto...

FixO3: Advancement towards Open Ocean Observatory Data Management Harmonisation

Science.gov (United States)

Behnken, Andree; Pagnani, Maureen; Huber, Robert; Lampitt, Richard

2015-04-01

Since 2002 there has been a sustained effort, supported as European framework projects, to harmonise both the technology and the data management of Open Ocean fixed observatories run by European nations. FixO3 started in September 2013, and for 3 more years will coordinate the convergence of data management best practice across a constellation of moorings in the Atlantic, in both hemispheres, and in the Mediterranean. To ensure the continued existence of these unique sources of oceanographic data as sustained observatories it is vital to improve access to the data collected, both in terms of methods of presentation, real-time availability, long-term archiving and quality assurance. The data management component of FixO3 improves access to marine observatory data by harmonising data management standards, formats and workflows covering the complete life cycle of data from real time data acquisition to long-term archiving. Legal and data policy aspects have been examined and discussed to identify transnational barriers to open-access to marine observatory data. As a result, a harmonised FixO3 data policy was drafted, which provides a formal basis for data exchange between FixO3 infrastructures, and also enables open access to data for the general public. FixO3 interacts with other European infrastructures such as EMODnet, SeaDataNet, PANGAEA, and especially aims to harmonise efforts with OceanSites and MyOcean. The project landing page (www.fixo3.eu) offers detailed information about every observatory as well as data visualisations and direct downloads. In addition to this, metadata for all FixO3 - relevant data are available from the searchable FixO3 metadata catalogue, which is also accessible from the project web page. This catalogue is hosted by PANGAEA and receives updates in regular intervals. The FixO3 Standards & Services registry ties in with the GEOSS Components and Services Registry (CSR) and provides additional observatory information. The data management

Human-Centric Wireless Communication Networks

OpenAIRE

Cavallari, Riccardo

2016-01-01

This thesis covers two main topics: the design and performance evaluation of Wireless Body Area Networks (WBANs), and the simulation and mathematical modeling of Delay Tolerant Networks (DTNs). Different Medium Access Control (MAC) protocols for WBANs are implemented on dedicated hardware in order to evaluate, through extensive measurement campaigns, the performance of the network in terms of packet loss rate, delay and energy consumption. Novel solutions to cope with bo...

Performance of the hybrid wireless mesh protocol for wireless mesh networks

DEFF Research Database (Denmark)

Boye, Magnus; Staalhagen, Lars

2010-01-01

Wireless mesh networks offer a new way of providing end-user access and deploying network infrastructure. Though mesh networks offer a price competitive solution to wired networks, they also come with a set of new challenges such as optimal path selection, channel utilization, and load balancing....... and proactive. Two scenarios of different node density are considered for both path selection modes. The results presented in this paper are based on a simulation model of the HWMP specification in the IEEE 802.11s draft 4.0 implemented in OPNET Modeler....

An economical wireless cavity-nest viewer

Science.gov (United States)

Daniel P. Huebner; Sarah R. Hurteau

2007-01-01

Inspection of cavity nests and nest boxes is often required during studies of cavity-nesting birds, and fiberscopes and pole-mounted video cameras are sometimes used for such inspection. However, the cost of these systems may be prohibitive for some potential users. We describe a user-built, wireless cavity viewer that can be used to access cavities as high as 15 m and...

ALOHA Random Access that Operates as a Rateless Code

DEFF Research Database (Denmark)

Stefanovic, Cedomir; Popovski, Petar

2013-01-01

Various applications of wireless Machine-to-Machine (M2M) communications have rekindled the research interest in random access protocols, suitable to support a large number of connected devices. Slotted ALOHA and its derivatives represent a simple solution for distributed random access in wireless...... the contention when the instantaneous throughput is maximized. The paper presents the related analysis, providing heuristic criteria for terminating the contention period and showing that very high throughputs can be achieved, even for a low number for contending users. The demonstrated results potentially have...

Analyzing Options for Airborne Emergency Wireless Communications

Energy Technology Data Exchange (ETDEWEB)

Michael Schmitt; Juan Deaton; Curt Papke; Shane Cherry

2008-03-01

In the event of large-scale natural or manmade catastrophic events, access to reliable and enduring commercial communication systems is critical. Hurricane Katrina provided a recent example of the need to ensure communications during a national emergency. To ensure that communication demands are met during these critical times, Idaho National Laboratory (INL) under the guidance of United States Strategic Command has studied infrastructure issues, concerns, and vulnerabilities associated with an airborne wireless communications capability. Such a capability could provide emergency wireless communications until public/commercial nodes can be systematically restored. This report focuses on the airborne cellular restoration concept; analyzing basic infrastructure requirements; identifying related infrastructure issues, concerns, and vulnerabilities and offers recommended solutions.

Broadcast of four HD videos with LED ceiling lighting: optical-wireless MAC

Science.gov (United States)

Bouchet, Olivier; Porcon, Pascal; Gueutier, Eric

2011-09-01

The European project "hOME Gigabit Access Network" (OMEGA) targeted various wireless and wired solutions for 1 Gbit/s connectivity in Home Area Networks (HANs). One objective was to evaluate the suitability of optical wireless technologies in two spectral regions: visible light (visible-light communications - VLC) and near infrared (infrared communications - IRC). Several demonstrators have been built, all of them largely relying on overthe- shelf components. The demonstrators included a "wide-area" VLC broadcast link based on LED ceiling lighting and a laser-based high-data-rate "wide-area" IRC prototype. In this paper we discuss an adapted optical-wireless media-access-control (OWMAC) sublayer, which was developed and implemented during the project. It is suitable for both IRC and VLC. The VLC prototype is based on DMT signal processing and provides broadcasting at { 100 Mbit/s over an area of approximately 5 m2. The IRC prototype provides {300 Mbit/s half-duplex communication over an area of approximately 30 m2. The IRC mesh network, composed of one base station and two terminals, is based on OOK modulation, multi-sector transceivers, and an ultra-fast sector switch. After a brief discussion about the design of the optical-wireless data link layer and the optical-wireless switch (OWS) card, we address the card development and implementation. We also present applications for the VLC and IRC prototypes and measurement results regarding the MAC layer.

Efficient Smart Antenna Systems (4G) For CDMA Wireless Communication

OpenAIRE

Singla, Brahm Mohinder; Kumar, Ashish

2012-01-01

Today, mobile communications play a central role in the voice/data network arena. With the deployment of mass scale 3G just around the corner, new directions are already being researched. In this paper we address about the 4TH G mobile communications.The Fourth Generation (4G) Mobile Communications should not focus only on the data-rate increase and new air interface.4G Mobile should instead con-verge the advanced wireless mobile communications and high-speed wireless access systems into an O...

A wireless computational platform for distributed computing based traffic monitoring involving mixed Eulerian-Lagrangian sensing

KAUST Repository

Jiang, Jiming; Claudel, Christian G.

2013-01-01

.4GHz 802.15.4 ISM compliant radio module, and can be interfaced with fixed traffic sensors, or receive data from vehicle transponders. The platform is specially designed and optimized to be integrated in a solar-powered wireless sensor network in which

Wireless Cellular Mobile Communications

OpenAIRE

Zalud, V.

2002-01-01

In this article is briefly reviewed the history of wireless cellular mobile communications, examined the progress in current second generation (2G) cellular standards and discussed their migration to the third generation (3G). The European 2G cellular standard GSM and its evolution phases GPRS and EDGE are described somewhat in detail. The third generation standard UMTS taking up on GSM/GPRS core network and equipped with a new advanced access network on the basis of code division multiple ac...

Energy efficiency in hybrid mobile and wireless networks

Energy Technology Data Exchange (ETDEWEB)

Abbas, Ziaul Haq

2012-07-01

Wireless Internet access is almost pervasive nowadays, and many types of wireless networks can be used to access the Internet. However, along with this growth, there is an even greater concern about the energy consumption and efficiency of mobile devices as well as of the supporting networks, triggering the appearance of the concept of green communication. While some efforts have been made towards this direction, challenges still exist and need to be tackled from diverse perspectives. Cellular networks, WLANs, and ad hoc networks in the form of wireless mesh networks are the most popular technologies for wireless Internet access. The availability of such a variety of access networks has also paved the way to explore synergistic approaches for Internet access, leading to the concept of hybrid networks and relay communications. In addition, many mobile devices are being equipped with multiple interfaces, enabling them to operate in hybrid networks. In contrast, the improvements in the battery technology itself have not matched the pace of the emerging mobile applications. The situation becomes more sophisticated when a mobile device functions also as a relay node to forward other station's data. In the literature, energy efficiency of mobile devices has been addressed from various perspectives such as protocol-level efforts, battery management efforts, etc. However, there is little work on energy efficiency in hybrid mobile and wireless networks and devices with heterogeneous connections. For example, when there are multiple networks available to a mobile device, how to achieve optimum long-term energy consumption of such a device is an open question. Furthermore, in today's cellular networks, micro-, pico-, and femto-cells are the most popular network topologies in order to support high data rate services and high user density. With the growth of such small-cell solutions, the energy consumption of these networks is also becoming an important concern for operators

Parity-Check Network Coding for Multiple Access Relay Channel in Wireless Sensor Cooperative Communications

Directory of Open Access Journals (Sweden)

Du Bing

2010-01-01

Full Text Available A recently developed theory suggests that network coding is a generalization of source coding and channel coding and thus yields a significant performance improvement in terms of throughput and spatial diversity. This paper proposes a cooperative design of a parity-check network coding scheme in the context of a two-source multiple access relay channel (MARC model, a common compact model in hierarchical wireless sensor networks (WSNs. The scheme uses Low-Density Parity-Check (LDPC as the surrogate to build up a layered structure which encapsulates the multiple constituent LDPC codes in the source and relay nodes. Specifically, the relay node decodes the messages from two sources, which are used to generate extra parity-check bits by a random network coding procedure to fill up the rate gap between Source-Relay and Source-Destination transmissions. Then, we derived the key algebraic relationships among multidimensional LDPC constituent codes as one of the constraints for code profile optimization. These extra check bits are sent to the destination to realize a cooperative diversity as well as to approach MARC decode-and-forward (DF capacity.

Opportunistic-harvesting: RF wireless power transfer scheme for multiple access relays system

NARCIS (Netherlands)

Rajaram, A.; Jayakody, D.N.K.; Srinivasan, K.; Chen, B.; Sharma, V.

2017-01-01

Wireless communications have become one of the main stake holders on which our contemporary world relies for carrying out many daily activities. In this era, the number of connected devices is increasing rapidly, contemplating not only smart phone, but also growing connectivity of machines, sensors,

Wireless Augmented Reality Prototype (WARP)

Science.gov (United States)

Devereaux, A. S.

1999-01-01

Initiated in January, 1997, under NASA's Office of Life and Microgravity Sciences and Applications, the Wireless Augmented Reality Prototype (WARP) is a means to leverage recent advances in communications, displays, imaging sensors, biosensors, voice recognition and microelectronics to develop a hands-free, tetherless system capable of real-time personal display and control of computer system resources. Using WARP, an astronaut may efficiently operate and monitor any computer-controllable activity inside or outside the vehicle or station. The WARP concept is a lightweight, unobtrusive heads-up display with a wireless wearable control unit. Connectivity to the external system is achieved through a high-rate radio link from the WARP personal unit to a base station unit installed into any system PC. The radio link has been specially engineered to operate within the high- interference, high-multipath environment of a space shuttle or space station module. Through this virtual terminal, the astronaut will be able to view and manipulate imagery, text or video, using voice commands to control the terminal operations. WARP's hands-free access to computer-based instruction texts, diagrams and checklists replaces juggling manuals and clipboards, and tetherless computer system access allows free motion throughout a cabin while monitoring and operating equipment.

Ubiquitous wireless ECG recording: a powerful tool physicians should embrace.

Science.gov (United States)

Saxon, Leslie A

2013-04-01

The use of smart phones has increased dramatically and there are nearly a billion users on 3G and 4G networks worldwide. Nearly 60% of the U.S. population uses smart phones to access the internet, and smart phone sales now surpass those of desktop and laptop computers. The speed of wireless communication technology on 3G and 4G networks and the widespread adoption and use of iOS equipped smart phones (Apple Inc., Cupertino, CA, USA) provide infrastructure for the transmission of wireless biomedical data, including ECG data. These technologies provide an unprecedented opportunity for physicians to continually access data that can be used to detect issues before symptoms occur or to have definitive data when symptoms are present. The technology also greatly empowers and enables the possibility for unprecedented patient participation in their own medical education and health status as well as that of their social network. As patient advocates, physicians and particularly cardiac electrophysiologists should embrace the future and promise of wireless ECG recording, a technology solution that can truly scale across the global population. © 2013 Wiley Periodicals, Inc.

E- and W-band high-capacity hybrid fiber-wireless link

DEFF Research Database (Denmark)

Vegas Olmos, Juan José; Pang, Xiaodan; Tafur Monroy, Idelfonso

2014-01-01

In this paper we summarize the work conducted in our group in the area of E- and W-band optical high-capacity fiber-wireless links. We present performance evaluations of E- and W-band mm-wave signal generation using photonic frequency upconversion employing both VCSELs and ECLs, along with transm...... in mobile backhaul/fronthaul applications, dense distributed antenna systems and fiber-over-radio scenarios.......In this paper we summarize the work conducted in our group in the area of E- and W-band optical high-capacity fiber-wireless links. We present performance evaluations of E- and W-band mm-wave signal generation using photonic frequency upconversion employing both VCSELs and ECLs, along...... with transmission over different type of optical fibers and for a number of values for the wireless link distance. Hybrid wireless-optical links can be composed of mature and resilient technology available off-the-shelf, and provide functionalities that can add value to optical access networks, specifically...

Energy harvesting for wireless sensors by using piezoelectric transducers

Energy Technology Data Exchange (ETDEWEB)

Duerager, Christian [Empa, Swiss Federal Laboratories for Materials Science and Technology, Duebendorf (Switzerland)

2012-07-01

Wireless sensor technology, which integrates transducers, measurement electronics and wireless communication, has become increasingly vital in structural health monitoring (SHM) applications. Compared to traditional wired systems, wireless solutions reduce the installation time and costs and are not subjected to breakage caused by harsh weather conditions or other extreme events. Because of the low installation costs, wireless sensor networks allow the deployment of a big number of wireless sensor nodes on the structures. Moreover, the nodes can be placed on particularly critical components of the structure difficult to reach by wires. In most of the cases the power supply are conventional batteries, which could be a problem because of their finite life span. Furthermore, in the case of wireless sensor nodes located on structures, it is often advantageous to embed them, which makes an access impossible. Therefore, if a method of obtaining the untapped energy surrounding these sensors was implemented, significant life could be added to the power supply. Various approaches to energy harvesting and energy storage are discussed and limitations associated with the current technology are addressed. In this paper we first discuss the research that has been performed in the area of energy harvesting for wireless sensor technologies by using the ambient vibration energy. In many cases the energy produced by the ambient vibrations is far too small to directly power a wireless sensor node. Therefore, in a second step we discuss the development process for an electronic energy harvesting circuit optimized for piezoelectric transducers. In the last part of this paper an experiment with different piezoelectric transducers and their applicability for energy harvesting applications on vibrating structures will be discussed. (orig.)

Multichannel signal enhancement using a remote wireless microphone

NARCIS (Netherlands)

Bloemendal, Brian; Van De Laar, Jakob; Sommen, Piet

2012-01-01

A novel approach to multichannel signal enhancement is presented that exploits data from a remote wireless microphone (RWM). This RWM is placed near an interfering source and transmits only autocorrelation data of its observations to a host, i.e., not the entire signal. The host has access to the

Web: A Wireless Experiment Box for the Dextre Pointing Package ELC Payload

Science.gov (United States)

Bleier, Leor Z.; Marrero-Fontanez, Victor J.; Sparacino, Pietro A.; Moreau, Michael C.; Mitchell, Jason W.

2012-01-01

The Wireless Experiment Box (WEB) was proposed to work with the International Space Station (ISS) External Wireless Communication (EWC) system to support high-definition video from the Dextre Pointing Package (DPP). DPP/WEB was a NASA GSFC proposed ExPRESS Logistics Carrier (ELC) payload designed to flight test an integrated suite of Autonomous Rendezvous and Docking (AR&D) technologies to enable a wide spectrum of future missions across NASA and other US Government agencies. The ISS EWC uses COTS Wireless Access Points (WAPs) to provide high-rate bi-directional communications to ISS. In this paper, we discuss WEB s packaging, operation, antenna development, and performance testing.

WEB - A Wireless Experiment Box for the Dextre Pointing Package ELC Payload

Science.gov (United States)

Bleier, Leor Z.; Marrero-Fontanez, Victor J.; Sparacino, Pietro A.; Moreau, Michael C.; Mitchell, Jason William

2012-01-01

The Wireless Experiment Box (WEB) was proposed to work with the International Space Station (ISS) External Wireless Communication (EWC) system to support high-definition video from the Dextre Pointing Package (DPP). DPP/WEB was a NASA GSFC proposed ExPRESS Logistics Carrier (ELC) payload designed to flight test an integrated suite of Autonomous Rendezvous and Docking (AR&D) technologies to enable a wide spectrum of future missions across NASA and other US Government agencies. The ISS EWC uses COTS Wireless Access Points (WAPs) to provide high-rate bi-directional communications to ISS. In this paper, we discuss WEB s packaging, operation, antenna development, and performance testing.

Energy-efficient digital and wireless IC design for wireless smart sensing

Science.gov (United States)

Zhou, Jun; Huang, Xiongchuan; Wang, Chao; Tae-Hyoung Kim, Tony; Lian, Yong

2017-10-01

Wireless smart sensing is now widely used in various applications such as health monitoring and structural monitoring. In conventional wireless sensor nodes, significant power is consumed in wirelessly transmitting the raw data. Smart sensing adds local intelligence to the sensor node and reduces the amount of wireless data transmission via on-node digital signal processing. While the total power consumption is reduced compared to conventional wireless sensing, the power consumption of the digital processing becomes as dominant as wireless data transmission. This paper reviews the state-of-the-art energy-efficient digital and wireless IC design techniques for reducing the power consumption of the wireless smart sensor node to prolong battery life and enable self-powered applications.

Medium access control and hardware prototype designs for low-energy wireless sensor networks

Energy Technology Data Exchange (ETDEWEB)

Kohvakka, M.

2009-07-01

A Wireless Sensor Network (WSN) is an emerging technology consisting of small, cheap, and ultra-low energy sensor nodes, which cooperatively monitor physical quantities, actuate, and perform data processing tasks. A deployment may comprise thousands of randomly distributed autonomous nodes, which must self-configure and create a multi-hop network topology.This thesis focuses on low-energy WSNs targeting to long network lifetime. The main research problem is the combination of adaptive and scalable multi-hop networking with constrained energy budget, processing power, and communication bandwidth. The research problem is approached by energy-efficient protocols and low-power sensor node platforms. The main contribution of this thesis is an energy-efficient Medium Access Control (MAC) design for TUTWSN (Tampere University of Technology Wireless Sensor Network). The design comprises channel access and networking mechanisms, which specify data exchange, link synchronization, network self-configuration, and neighbor discovery operations. The second outcome are several low-power sensor node platforms, which have been designed and implemented to evaluate the performance of the MAC design and hardware components in real deployments. The third outcome are the performance models and analysis of several MAC designs including TUTWSN, IEEE 802.15.4, and the most essential research proposals.The results and conclusion of this Thesis indicate that it is possible to implement multi-hop WSNs in harsh and dynamic operation conditions with years of lifetime using current low-cost components and batteries. Energy analysis results indicate that the lowest energy consumption is achieved by using simple and high data-rate transceivers. It is also critical to minimize sleep mode power consumption of all components and to use accurate wake-up timers. However, the selection of components constitutes only a minor part of the solution, and an energy-efficient MAC layer design being able to

Application of wireless LAN technology to remote monitoring for inspection equipment

International Nuclear Information System (INIS)

Ishiyama, Koichi; Kimura, Takashi; Miura, Yasushi; Yamaguchi, Katsuhiro; Kabuki, Toshihide

2011-01-01

To support inspections under an Integrated Safeguards regime into Tokai Reprocessing Plant (TRP), the IAEA suggested making use of Remote Monitoring (RM) capabilities to the inspection equipment (surveillance camera and NDA systems) installed in the spent fuel storage area at TRP. Since TRP had no pre-prepared cabling infrastructure for data transmission in the spent fuel storage area, the option of wireless LAN was chosen over the telephone line due to its lower installation costs. Feasibility studies and tests were performed by TRP on communication and particularly on long-term continuous communication using wireless LAN equipment composed of APs (AP: Access Point) and the external antennas for introducing wireless LAN technology to RM. As a result it was recognized that wireless LAN has enough ability to communicate for long periods of time and consequently the IAEA installed the AP and the external antenna to each inspection equipment and the wireless LAN technology was applied for RM. In this paper, the summary of each test and the results are reported. (author)

Optical wireless link between a nanoscale antenna and a transducing rectenna.

Science.gov (United States)

Dasgupta, Arindam; Mennemanteuil, Marie-Maxime; Buret, Mickaël; Cazier, Nicolas; Colas-des-Francs, Gérard; Bouhelier, Alexandre

2018-05-18

Initiated as a cable-replacement solution, short-range wireless power transfer has rapidly become ubiquitous in the development of modern high-data throughput networking in centimeter to meter accessibility range. Wireless technology is now penetrating a higher level of system integration for chip-to-chip and on-chip radiofrequency interconnects. However, standard CMOS integrated millimeter-wave antennas have typical size commensurable with the operating wavelength, and are thus an unrealistic solution for downsizing transmitters and receivers to the micrometer and nanometer scale. Herein, we demonstrate a light-in and electrical signal-out, on-chip wireless near-infrared link between a 220 nm optical antenna and a sub-nanometer rectifying antenna converting the transmitted optical energy into direct electrical current. The co-integration of subwavelength optical functional devices with electronic transduction offers a disruptive solution to interface photons and electrons at the nanoscale for on-chip wireless optical interconnects.

Dynamic power control for wireless backbone mesh networks: a survey

CSIR Research Space (South Africa)

Olwal, TO

2010-01-01

Full Text Available points of failures, and robust against RF interference, obstacles or power outage. This is because WMRs forming wireless backbone mesh networks (WBMNs) are built on advanced physical technologies. Such nodes perform both accessing and forwarding...

Wireless Technology Use Case Requirement Analysis for Future Space Applications

Science.gov (United States)

Abedi, Ali; Wilkerson, DeLisa

2016-01-01

This report presents various use case scenarios for wireless technology -including radio frequency (RF), optical, and acoustic- and studies requirements and boundary conditions in each scenario. The results of this study can be used to prioritize technology evaluation and development and in the long run help in development of a roadmap for future use of wireless technology. The presented scenarios cover the following application areas: (i) Space Vehicles (manned/unmanned), (ii) Satellites and Payloads, (iii) Surface Explorations, (iv) Ground Systems, and (v) Habitats. The requirement analysis covers two parallel set of conditions. The first set includes the environmental conditions such as temperature, radiation, noise/interference, wireless channel characteristics and accessibility. The second set of requirements are dictated by the application and may include parameters such as latency, throughput (effective data rate), error tolerance, and reliability. This report provides a comprehensive overview of all requirements from both perspectives and details their effects on wireless system reliability and network design. Application area examples are based on 2015 NASA Technology roadmap with specific focus on technology areas: TA 2.4, 3.3, 5.2, 5.5, 6.4, 7.4, and 10.4 sections that might benefit from wireless technology.

Wired or Wireless Internet?

DEFF Research Database (Denmark)

Gimpel, Gregory

2010-01-01

This paper finds that network externalities play a minimal role in the choice of internet access technology. Potential adopters of mobile laptop internet view broadband technology as a black box, the technological details of which donot matter. The study uses qualitative techniques to explore how...... the speed of technological obsolescence, market share dominance, and the black boxing of technology influence consumer intention to adopt WiMax and 3G wireless internet for their laptop computers. The results, implications for industry, and areas for further research are discussed....

A forensic readiness model for Wireless Local Area Networks

CSIR Research Space (South Africa)

Ngobeni, S

2010-01-01

Full Text Available of cyber crime, where criminals deliberately and actively break into WLANs with the intent to cause harm or access sensitive information. WLAN digital forensics is seen not only as a response to cyber crime in wireless environments, but also as a means...

Next Generation RFID-Based Medical Service Management System Architecture in Wireless Sensor Network

Science.gov (United States)

Tolentino, Randy S.; Lee, Kijeong; Kim, Yong-Tae; Park, Gil-Cheol

Radio Frequency Identification (RFID) and Wireless Sensor Network (WSN) are two important wireless technologies that have wide variety of applications and provide unlimited future potentials most especially in healthcare systems. RFID is used to detect presence and location of objects while WSN is used to sense and monitor the environment. Integrating RFID with WSN not only provides identity and location of an object but also provides information regarding the condition of the object carrying the sensors enabled RFID tag. However, there isn't any flexible and robust communication infrastructure to integrate these devices into an emergency care setting. An efficient wireless communication substrate for medical devices that addresses ad hoc or fixed network formation, naming and discovery, transmission efficiency of data, data security and authentication, as well as filtration and aggregation of vital sign data need to be study and analyze. This paper proposed an efficient next generation architecture for RFID-based medical service management system in WSN that possesses the essential elements of each future medical application that are integrated with existing medical practices and technologies in real-time, remote monitoring, in giving medication, and patient status tracking assisted by embedded wearable wireless sensors which are integrated in wireless sensor network.

Contemporary, emerging, and ratified wireless security standards: an update for the networked dental office.

Science.gov (United States)

Mupparapu, Muralidhar

2006-02-15

Wireless networking is not new to contemporary dental offices around the country. Wireless routers and network cards have made access to patient records within the office handy and, thereby, saving valuable chair side time and increasing productivity. As is the case with any rapidly developing technology, wireless technology also changes with the same rate. Unless, the users of the wireless networking understand the implications of these changes and keep themselves updated periodically, the office network will become obsolete very quickly. This update of the emerging security protocols and pertaining to ratified wireless 802.11 standards will be timely for the contemporary dentist whose office is wirelessly networked. This article brings the practicing dentist up-to-date on the newer versions and standards in wireless networking that are changing at a fast pace. The introduction of newer 802.11 standards like super G, Super AG, Multiple Input Multiple Output (MIMO), and pre-n are changing the pace of adaptation of this technology. Like any other rapidly transforming technology, information pertaining to wireless networking should be a priority for the contemporary dentist, an eventual end-user in order to be a well-informed and techno-savvy consumer.

Application of an automated wireless structural monitoring system for long-span suspension bridges

International Nuclear Information System (INIS)

Kurata, M.; Lynch, J. P.; Linden, G. W. van der; Hipley, P.; Sheng, L.-H.

2011-01-01

This paper describes an automated wireless structural monitoring system installed at the New Carquinez Bridge (NCB). The designed system utilizes a dense network of wireless sensors installed in the bridge but remotely controlled by a hierarchically designed cyber-environment. The early efforts have included performance verification of a dense network of wireless sensors installed on the bridge and the establishment of a cellular gateway to the system for remote access from the internet. Acceleration of the main bridge span was the primary focus of the initial field deployment of the wireless monitoring system. An additional focus of the study is on ensuring wireless sensors can survive for long periods without human intervention. Toward this end, the life-expectancy of the wireless sensors has been enhanced by embedding efficient power management schemes in the sensors while integrating solar panels for power harvesting. The dynamic characteristics of the NCB under daily traffic and wind loads were extracted from the vibration response of the bridge deck and towers. These results have been compared to a high-fidelity finite element model of the bridge.

Application of AN Automated Wireless Structural Monitoring System for Long-Span Suspension Bridges

Science.gov (United States)

Kurata, M.; Lynch, J. P.; van der Linden, G. W.; Hipley, P.; Sheng, L.-H.

2011-06-01

This paper describes an automated wireless structural monitoring system installed at the New Carquinez Bridge (NCB). The designed system utilizes a dense network of wireless sensors installed in the bridge but remotely controlled by a hierarchically designed cyber-environment. The early efforts have included performance verification of a dense network of wireless sensors installed on the bridge and the establishment of a cellular gateway to the system for remote access from the internet. Acceleration of the main bridge span was the primary focus of the initial field deployment of the wireless monitoring system. An additional focus of the study is on ensuring wireless sensors can survive for long periods without human intervention. Toward this end, the life-expectancy of the wireless sensors has been enhanced by embedding efficient power management schemes in the sensors while integrating solar panels for power harvesting. The dynamic characteristics of the NCB under daily traffic and wind loads were extracted from the vibration response of the bridge deck and towers. These results have been compared to a high-fidelity finite element model of the bridge.

Optical wireless communications to OC-768 and beyond

Science.gov (United States)

Medved, David B.; Davidovich, Leonid

2001-10-01

Laser and LED-based wireless communication systems are currently providing license-free interconnection for broadband voice, data and video transport. These systems allow for the immediate, reliable and low-cost extension of copper and fiber-based networks to any end user, providing efficient First Mile bypass access to high data rate backbone networks at speeds ranging from T-1 voice to full throughput ATM at 155 Mbps and up to Gigabit Ethernet. These wireless optical beams constitute a Virtual Fiber in the air, providing the capabilities of fiber in situations where wired connectivity is unavailable, impractical, expensive or slow-to-implement, while achieving a combination of low cost, speed and reliability that cannot be matched by microwave, mm wave, spread spectrum or other competing (actually complementary) wireless technologies. The carrier frequency of the optical beam is about 10,000 times higher than the highest frequencies used by the millimeter wave technology. By means of Wavelength Division Multiplexing more than 1000 independent data channels can be projected into the air on a single beam thus providing a potential bandwidth ten million times that of any RF solution. The twin barriers of physics and regulatory bureaucracy to this essentially infinite wireless bandwidth are thus eliminated by this Virtual Fiber. As user density and individual bandwidth needs escalate, the optical wireless will be the preferred medium of choice in both network and cellular interconnection. A mesh topology which integrates our optical wireless systems with the latest Optical Access switches and routing equipment will be described using case study examples from Japan to South America. As the Bandwidth Blowout continues to push the limits of electronics and especially in the case of DWDM (Dense Wavelength Division Multiples), the conventional optical wireless solutions are no longer feasible. Instead of using f.o. transceivers to convert photons to electrons and thence

Buffer management in wireless full-duplex systems

KAUST Repository

Bouacida, Nader

2015-10-19

Wireless full-duplex radios can simultaneously transmit and receive using the same frequency. In theory, this can double the throughput. In fact, there is only little work addressing aspects other than throughput gains in full-duplex systems. Over-buffering in today\\'s networks or the so-called “bufferbloat” phenomenon creates excessive end-to-end delays resulting in network performance degradation. Our analysis shows that full-duplex systems may suffer from high latency caused by bloated buffers. In this paper, we address the problem of buffer management in full-duplex networks by using Wireless Queue Management (WQM), which is an active queue management technique for wireless networks. Our solution is based on Relay Full-Duplex MAC (RFD-MAC), an asynchronous media access control protocol designed for relay full-duplexing. We compare the performance of WQM in full-duplex environment to Drop Tail mechanism over various scenarios. Our solution reduces the end-to-end delay by two orders of magnitude while achieving similar throughput in most of the cases.

Mobility management techniques for the next-generation wireless networks

Science.gov (United States)

Sun, Junzhao; Howie, Douglas P.; Sauvola, Jaakko J.

2001-10-01

The tremendous demands from social market are pushing the booming development of mobile communications faster than ever before, leading to plenty of new advanced techniques emerging. With the converging of mobile and wireless communications with Internet services, the boundary between mobile personal telecommunications and wireless computer networks is disappearing. Wireless networks of the next generation need the support of all the advances on new architectures, standards, and protocols. Mobility management is an important issue in the area of mobile communications, which can be best solved at the network layer. One of the key features of the next generation wireless networks is all-IP infrastructure. This paper discusses the mobility management schemes for the next generation mobile networks through extending IP's functions with mobility support. A global hierarchical framework model for the mobility management of wireless networks is presented, in which the mobility management is divided into two complementary tasks: macro mobility and micro mobility. As the macro mobility solution, a basic principle of Mobile IP is introduced, together with the optimal schemes and the advances in IPv6. The disadvantages of the Mobile IP on solving the micro mobility problem are analyzed, on the basis of which three main proposals are discussed as the micro mobility solutions for mobile communications, including Hierarchical Mobile IP (HMIP), Cellular IP, and Handoff-Aware Wireless Access Internet Infrastructure (HAWAII). A unified model is also described in which the different micro mobility solutions can coexist simultaneously in mobile networks.

Capacity analysis of wireless mesh networks | Gumel | Nigerian ...

African Journals Online (AJOL)

... number of nodes (n) in a linear topology. The degradation is found to be higher in a fully mesh network as a result of increase in interference and MAC layer contention in the network. Key words: Wireless mesh network (WMN), Adhoc network, Network capacity analysis, Bottleneck collision domain, Medium access control ...

IP communication optimization for 6LoWPAN-Based Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Li MA

2014-07-01

Full Text Available The emergence of 6LoWPAN makes it possible that Wireless Sensor Networks access to the Internet. However, the cost of IP communication between 6LoWPAN wireless sensor node and external internet node is still relatively high. This paper proposed a new addressing configuration and compression scheme in 6LoWPAN network called IPHC-NAT, which largely reduced the proportion of the IP header in 6LoWPAN packet, designed and constructed a bidirectional data transmission gateway to connect 6LoWPAN wireless sensor node with IPv6 client. The experimental results show the feasibility of the design of IPHC-NAT and the data transmission efficiency has significantly been improved compared to the original 6LoWPAN network.

Simulation and Emulation of MIMO Wireless Baseband Transceivers

Directory of Open Access Journals (Sweden)

Andreas Burg

2010-01-01

Full Text Available The development of state-of-the-art wireless communication transceivers in semiconductor technology is a challenging process due to complexity and stringent requirements of modern communication standards such as IEEE 802.11n. This tutorial paper describes a complete design, verification, and performance characterization methodology that is tailored to the needs of the development of state-of-the-art wireless baseband transceivers for both research and industrial products. Compared to the methods widely used for the development of communication research testbeds, the described design flow focuses on the evolution of a given system specification to a final ASIC implementation through multiple design representations. The corresponding verification and characterization environment supports rapid floating-point and fixed-point performance characterization and ensures consistency across the entire design process and across all design representations. This framework has been successfully employed for the development and verification of an industrial-grade, fully standard compliant, 4-stream IEEE 802.11n MIMO-OFDM baseband transceiver.

Wireless mesh networks.

Science.gov (United States)

Wang, Xinheng

2008-01-01

Wireless telemedicine using GSM and GPRS technologies can only provide low bandwidth connections, which makes it difficult to transmit images and video. Satellite or 3G wireless transmission provides greater bandwidth, but the running costs are high. Wireless networks (WLANs) appear promising, since they can supply high bandwidth at low cost. However, the WLAN technology has limitations, such as coverage. A new wireless networking technology named the wireless mesh network (WMN) overcomes some of the limitations of the WLAN. A WMN combines the characteristics of both a WLAN and ad hoc networks, thus forming an intelligent, large scale and broadband wireless network. These features are attractive for telemedicine and telecare because of the ability to provide data, voice and video communications over a large area. One successful wireless telemedicine project which uses wireless mesh technology is the Emergency Room Link (ER-LINK) in Tucson, Arizona, USA. There are three key characteristics of a WMN: self-organization, including self-management and self-healing; dynamic changes in network topology; and scalability. What we may now see is a shift from mobile communication and satellite systems for wireless telemedicine to the use of wireless networks based on mesh technology, since the latter are very attractive in terms of cost, reliability and speed.

Extending RTA/Linux with fixed-priority scheduling with deferred preemption

NARCIS (Netherlands)

Bergsma, M.; Holenderski, M.J.; Bril, R.J.; Lukkien, J.J.; Petters, S.M.; Zijlstra, P.

2009-01-01

Fixed-Priority Scheduling with Deferred Preemption (FPDS) is a middle ground between Fixed-Priority Pre-emptive Scheduling and Fixed-Priority Non-preemptive Scheduling, and offers advantages with respect to context switch overhead and resource access control. In this paper we present our work on

Design of handoff procedures for broadband wireless access IEEE 802.16 based networks

Directory of Open Access Journals (Sweden)

V. Rangel–Licea

2008-01-01

Full Text Available IEEE 802.16 is a protocol for fixed broad band wire less access that is currently trying to add mobility among mobile users in the standard. However, mobility adds some technical barriers that should be solved first, this is the case of HO "handoff" (change of connection between two base stations "BS" by a mobile user. In this paper, the problem of HO in IEEE 802.16 is approached try ing to maintain the quality of service (QoS of mobile users. A mechanism for changing connection during HO is pre sented. A simulation model based on OPNET MODELER1 was developed to evaluate the performance of the proposed HO mechanism. Finally, this paper demonstrates that it is possible to implement a seam less HO mech a nism over IEEE 802.16 even for users with de manding applications such as voice over IP.

Dynamic wireless sensor networks

CERN Document Server

Oteafy, Sharief M A

2014-01-01

In this title, the authors leap into a novel paradigm of scalability and cost-effectiveness, on the basis of resource reuse. In a world with much abundance of wirelessly accessible devices, WSN deployments should capitalize on the resources already available in the region of deployment, and only augment it with the components required to meet new application requirements. However, if the required resources already exist in that region, WSN deployment converges to an assignment and scheduling scheme to accommodate for the new application given the existing resources. Such resources are polled

Information Source Selection and Management Framework in Wireless Sensor Network

DEFF Research Database (Denmark)

Tobgay, Sonam; Olsen, Rasmus Løvenstein; Prasad, Ramjee

2013-01-01

information source selection and management framework and presents an algorithm which selects the information source based on the information mismatch probability [1]. The sampling rate for every access is decided as per the maximum allowable power consumption limit. Index Terms-wireless sensor network...

A Survey of Wireless Fair Queuing Algorithms with Location-Dependent Channel Errors

Directory of Open Access Journals (Sweden)

Anca VARGATU

2011-01-01

Full Text Available The rapid development of wireless networks has brought more and more attention to topics related to fair allocation of resources, creation of suitable algorithms, taking into account the special characteristics of wireless environment and insurance fair access to the transmission channel, with delay bound and throughput guaranteed. Fair allocation of resources in wireless networks requires significant challenges, because of errors that occur only in these networks, such as location-dependent and bursty channel errors. In wireless networks, frequently happens, because interference of radio waves, that a user experiencing bad radio conditions during a period of time, not to receive resources in that period. This paper analyzes some resource allocation algorithms for wireless networks with location dependent errors, specifying the base idea for each algorithm and the way how it works. The analyzed fair queuing algorithms differ by the way they treat the following aspects: how to select the flows which should receive additional services, how to allocate these resources, which is the proportion received by error free flows and how the flows affected by errors are compensated.

Wireless Handheld Computers in the Preclinical Undergraduate Curriculum

Directory of Open Access Journals (Sweden)

Matt Jackson

2003-02-01

Full Text Available This report presents the results of a pilot project using wireless PDAs as teaching tools in an undergraduate medical curriculum. This technology was used to foster a transition from a passive to an interactive learning environment in the classroom and provided a solution for the implementation of computer-based exams for a large class. Wayne State Medical School recently provided model e570 Toshiba PocketPCs® (personal digital assistants or PDAs, network interface cards, and application software developed by CampusMobility® to 20 sophomore medical students. The pilot group of preclinical students used the PDAs to access web-based course content, for communication, scheduling, to participate in interactive teaching sessions, and to complete course evaluations. Another part of this pilot has been to utilize the PDAs for computer-based exams in a wireless environment. Server authentication that restricted access during the exams and a proctoring console to monitor and record the PDA screens will be described in this report. Results of a student satisfaction survey will be presented.

Apparatus and method supporting wireless access to multiple security layers in an industrial control and automation system or other system

Science.gov (United States)

Chen, Yu-Gene T.

2013-04-16

A method includes receiving a message at a first wireless node. The first wireless node is associated with a first wired network, and the first wired network is associated with a first security layer. The method also includes transmitting the message over the first wired network when at least one destination of the message is located in the first security layer. The method further includes wirelessly transmitting the message for delivery to a second wireless node when at least one destination of the message is located in a second security layer. The second wireless node is associated with a second wired network, and the second wired network is associated with the second security layer. The first and second security layers may be associated with different security paradigms and/or different security domains. Also, the message could be associated with destinations in the first and second security layers.

A Multifactor Secure Authentication System for Wireless Payment

Science.gov (United States)

Sanyal, Sugata; Tiwari, Ayu; Sanyal, Sudip

Organizations are deploying wireless based online payment applications to expand their business globally, it increases the growing need of regulatory requirements for the protection of confidential data, and especially in internet based financial areas. Existing internet based authentication systems often use either the Web or the Mobile channel individually to confirm the claimed identity of the remote user. The vulnerability is that access is based on only single factor authentication which is not secure to protect user data, there is a need of multifactor authentication. This paper proposes a new protocol based on multifactor authentication system that is both secure and highly usable. It uses a novel approach based on Transaction Identification Code and SMS to enforce another security level with the traditional Login/password system. The system provides a highly secure environment that is simple to use and deploy with in a limited resources that does not require any change in infrastructure or underline protocol of wireless network. This Protocol for Wireless Payment is extended as a two way authentications system to satisfy the emerging market need of mutual authentication and also supports secure B2B communication which increases faith of the user and business organizations on wireless financial transaction using mobile devices.

Underwater Optical Wireless Communications, Networking, and Localization: A Survey

KAUST Repository

Saeed, Nasir; Celik, Abdulkadir; Al-Naffouri, Tareq Y.; Alouini, Mohamed-Slim

2018-01-01

Underwater wireless communications can be carried out through acoustic, radio frequency (RF), and optical waves. Compared to its bandwidth limited acoustic and RF counterparts, underwater optical wireless communications (UOWCs) can support higher data rates at low latency levels. However, severe aquatic channel conditions (e.g., absorption, scattering, turbulence, etc.) pose great challenges for UOWCs and significantly reduce the attainable communication ranges, which necessitates efficient networking and localization solutions. Therefore, we provide a comprehensive survey on the challenges, advances, and prospects of underwater optical wireless networks (UOWNs) from a layer by layer perspective which includes: 1) Potential network architectures; 2) Physical layer issues including propagation characteristics, channel modeling, and modulation techniques 3) Data link layer problems covering link configurations, link budgets, performance metrics, and multiple access schemes; 4) Network layer topics containing relaying techniques and potential routing algorithms; 5) Transport layer subjects such as connectivity, reliability, flow and congestion control; 6) Application layer goals and state-of-the-art UOWN applications, and 7) Localization and its impacts on UOWN layers. Finally, we outline the open research challenges and point out the future directions for underwater optical wireless communications, networking, and localization research.

Open-source telemedicine platform for wireless medical video communication.

Science.gov (United States)

Panayides, A; Eleftheriou, I; Pantziaris, M

2013-01-01

An m-health system for real-time wireless communication of medical video based on open-source software is presented. The objective is to deliver a low-cost telemedicine platform which will allow for reliable remote diagnosis m-health applications such as emergency incidents, mass population screening, and medical education purposes. The performance of the proposed system is demonstrated using five atherosclerotic plaque ultrasound videos. The videos are encoded at the clinically acquired resolution, in addition to lower, QCIF, and CIF resolutions, at different bitrates, and four different encoding structures. Commercially available wireless local area network (WLAN) and 3.5G high-speed packet access (HSPA) wireless channels are used to validate the developed platform. Objective video quality assessment is based on PSNR ratings, following calibration using the variable frame delay (VFD) algorithm that removes temporal mismatch between original and received videos. Clinical evaluation is based on atherosclerotic plaque ultrasound video assessment protocol. Experimental results show that adequate diagnostic quality wireless medical video communications are realized using the designed telemedicine platform. HSPA cellular networks provide for ultrasound video transmission at the acquired resolution, while VFD algorithm utilization bridges objective and subjective ratings.

Open-Source Telemedicine Platform for Wireless Medical Video Communication

Science.gov (United States)

Panayides, A.; Eleftheriou, I.; Pantziaris, M.

2013-01-01

An m-health system for real-time wireless communication of medical video based on open-source software is presented. The objective is to deliver a low-cost telemedicine platform which will allow for reliable remote diagnosis m-health applications such as emergency incidents, mass population screening, and medical education purposes. The performance of the proposed system is demonstrated using five atherosclerotic plaque ultrasound videos. The videos are encoded at the clinically acquired resolution, in addition to lower, QCIF, and CIF resolutions, at different bitrates, and four different encoding structures. Commercially available wireless local area network (WLAN) and 3.5G high-speed packet access (HSPA) wireless channels are used to validate the developed platform. Objective video quality assessment is based on PSNR ratings, following calibration using the variable frame delay (VFD) algorithm that removes temporal mismatch between original and received videos. Clinical evaluation is based on atherosclerotic plaque ultrasound video assessment protocol. Experimental results show that adequate diagnostic quality wireless medical video communications are realized using the designed telemedicine platform. HSPA cellular networks provide for ultrasound video transmission at the acquired resolution, while VFD algorithm utilization bridges objective and subjective ratings. PMID:23573082

Autonomous solutions for powering wireless sensor nodes in rivers

Science.gov (United States)

Kamenar, E.; Maćešić, S.; Gregov, G.; Blažević, D.; Zelenika, S.; Marković, K.; Glažar, V.

2015-05-01

There is an evident need for monitoring pollutants and/or other conditions in river flows via wireless sensor networks. In a typical wireless sensor network topography, a series of sensor nodes is to be deployed in the environment, all wirelessly connected to each other and/or their gateways. Each sensor node is composed of active electronic devices that have to be constantly powered. In general, batteries can be used for this purpose, but problems may occur when they have to be replaced. In the case of large networks, when sensor nodes can be placed in hardly accessible locations, energy harvesting can thus be a viable powering solution. The possibility to use three different small-scale river flow energy harvesting principles is hence thoroughly studied in this work: a miniaturized underwater turbine, a so-called `piezoelectric eel' and a hybrid turbine solution coupled with a rigid piezoelectric beam. The first two concepts are then validated experimentally in laboratory as well as in real river conditions. The concept of the miniaturised hydro-generator is finally embedded into the actual wireless sensor node system and its functionality is confirmed.

Open-Source Telemedicine Platform for Wireless Medical Video Communication

Directory of Open Access Journals (Sweden)

A. Panayides

2013-01-01

Full Text Available An m-health system for real-time wireless communication of medical video based on open-source software is presented. The objective is to deliver a low-cost telemedicine platform which will allow for reliable remote diagnosis m-health applications such as emergency incidents, mass population screening, and medical education purposes. The performance of the proposed system is demonstrated using five atherosclerotic plaque ultrasound videos. The videos are encoded at the clinically acquired resolution, in addition to lower, QCIF, and CIF resolutions, at different bitrates, and four different encoding structures. Commercially available wireless local area network (WLAN and 3.5G high-speed packet access (HSPA wireless channels are used to validate the developed platform. Objective video quality assessment is based on PSNR ratings, following calibration using the variable frame delay (VFD algorithm that removes temporal mismatch between original and received videos. Clinical evaluation is based on atherosclerotic plaque ultrasound video assessment protocol. Experimental results show that adequate diagnostic quality wireless medical video communications are realized using the designed telemedicine platform. HSPA cellular networks provide for ultrasound video transmission at the acquired resolution, while VFD algorithm utilization bridges objective and subjective ratings.

Underwater Optical Wireless Communications, Networking, and Localization: A Survey

KAUST Repository

Saeed, Nasir

2018-02-28

Underwater wireless communications can be carried out through acoustic, radio frequency (RF), and optical waves. Compared to its bandwidth limited acoustic and RF counterparts, underwater optical wireless communications (UOWCs) can support higher data rates at low latency levels. However, severe aquatic channel conditions (e.g., absorption, scattering, turbulence, etc.) pose great challenges for UOWCs and significantly reduce the attainable communication ranges, which necessitates efficient networking and localization solutions. Therefore, we provide a comprehensive survey on the challenges, advances, and prospects of underwater optical wireless networks (UOWNs) from a layer by layer perspective which includes: 1) Potential network architectures; 2) Physical layer issues including propagation characteristics, channel modeling, and modulation techniques 3) Data link layer problems covering link configurations, link budgets, performance metrics, and multiple access schemes; 4) Network layer topics containing relaying techniques and potential routing algorithms; 5) Transport layer subjects such as connectivity, reliability, flow and congestion control; 6) Application layer goals and state-of-the-art UOWN applications, and 7) Localization and its impacts on UOWN layers. Finally, we outline the open research challenges and point out the future directions for underwater optical wireless communications, networking, and localization research.

Traffic Agents for Improving QoS in Mixed Infrastructure and Ad Hoc Modes Wireless LAN

Directory of Open Access Journals (Sweden)

Yuan Hai-Feng

2006-01-01

Full Text Available As an important complement to infrastructured wireless networks, mobile ad hoc networks (MANET are more flexible in providing wireless access services, but more difficult in meeting different quality of service (QoS requirements for mobile customers. Both infrastructure and ad hoc network structures are supported in wireless local area networks (WLAN, which can offer high data-rate wireless multimedia services to the mobile stations (MSs in a limited geographical area. For those out-of-coverage MSs, how to effectively connect them to the access point (AP and provide QoS support is a challenging issue. By mixing the infrastructure and the ad hoc modes in WLAN, we propose in this paper a new coverage improvement scheme that can identify suitable idle MSs in good service zones as traffic agents (TAs to relay traffic from those out-of-coverage MSs to the AP. The service coverage area of WLAN is then expanded. The QoS requirements (e.g., bandwidth of those MSs are considered in the selection process of corresponding TAs. Mathematical analysis, verified by computer simulations, shows that the proposed TA scheme can effectively reduce blocking probability when traffic load is light.

``Low Power Wireless Technologies: An Approach to Medical Applications''

Science.gov (United States)

Bellido O., Francisco J.; González R., Miguel; Moreno M., Antonio; de La Cruz F, José Luis

Wireless communication supposed a great both -quantitative and qualitative, jump in the management of the information, allowing the access and interchange of it without the need of a physical cable connection. The wireless transmission of voice and information has remained in constant evolution, arising new standards like BluetoothTM, WibreeTM or ZigbeeTM developed under the IEEE 802.15 norm. These newest wireless technologies are oriented to systems of communication of short-medium distance and optimized for a low cost and minor consume, becoming recognized as a flexible and reliable medium for data communications across a broad range of applications due to the potential that the wireless networks presents to operate in demanding environments providing clear advantages in cost, size, power, flexibility, and distributed intelligence. About the medical applications, the remote health or telecare (also called eHealth) is getting a bigger place into the manufacturers and medical companies, in order to incorporate products for assisted living and remote monitoring of health parameteres. At this point, the IEEE 1073, Personal Health Devices Working Group, stablish the framework for these kind of applications. Particularly, the 1073.3.X describes the physical and transport layers, where the new ultra low power short range wireless technologies can play a big role, providing solutions that allow the design of products which are particularly appropriate for monitor people’s health with interoperability requirements.

Membrane potentials of membranes with fixed ionic sites

NARCIS (Netherlands)

van den Berg, Albert; van der Wal, P.D.; van der Wal, P.D.; Skowronska-ptasinska, M.; Sudhölter, E.J.R.; Sudholter, Ernst; Bergveld, Piet; Reinhoudt, David

1990-01-01

A theoretical model has been developed to simulate the formation of a membrane potential as a function of physically accessible parameters. The description is an extension of the well-known Teorell-Meyer-Sievers (TMS) model, now including free and fixed ionic sites and free and fixed neutral

Wireless Biological Electronic Sensors.

Science.gov (United States)

Cui, Yue

2017-10-09

The development of wireless biological electronic sensors could open up significant advances for both fundamental studies and practical applications in a variety of areas, including medical diagnosis, environmental monitoring, and defense applications. One of the major challenges in the development of wireless bioelectronic sensors is the successful integration of biosensing units and wireless signal transducers. In recent years, there are a few types of wireless communication systems that have been integrated with biosensing systems to construct wireless bioelectronic sensors. To successfully construct wireless biological electronic sensors, there are several interesting questions: What types of biosensing transducers can be used in wireless bioelectronic sensors? What types of wireless systems can be integrated with biosensing transducers to construct wireless bioelectronic sensors? How are the electrical sensing signals generated and transmitted? This review will highlight the early attempts to address these questions in the development of wireless biological electronic sensors.

Unlocking the Laboratory: Autonomous Wireless Sensor Authentication in Practice

Science.gov (United States)

Huggard, Meriel; McGoldrick, Ciaran

2013-01-01

Purpose: The purpose of this study is to evaluate a practical laboratory task where final year undergraduate students design, implement and validate an inferred security wireless sensor access system. Design/methodology/approach: The quality of the learning and technical environment was evaluated from a number of perspectives using a mixed methods…

Performance Evaluation of High Speed Multicarrier System for Optical Wireless Communication

Science.gov (United States)

Mathur, Harshita; Deepa, T.; Bartalwar, Sophiya

2018-04-01

Optical wireless communication (OWC) in the infrared and visible range is quite impressive solution, especially where radio communication face challenges. Visible light communication (VLC) uses visible light over a range of 400 and 800 THz and is a subdivision of OWC technologies. With an increasing demand for use of wireless communications, wireless access via Wi-Fi is facing many challenges especially in terms of capacity, availability, security and efficiency. VLC uses intensity modulation and direct detection (IM/DD) techniques and hence they require the signals to certainly be real valued positive sequences. These constraints pose limitation on digital modulation techniques. These limitations result in spectrum-efficiency or power-efficiency losses. In this paper, we investigate an amplitude shift keying (ASK) based orthogonal frequency division multiplexing (OFDM) signal transmission scheme using LabVIEW for VLC technology.

A Trace-Driven Analysis of Wireless Group Communication Mechanisms

Directory of Open Access Journals (Sweden)

Surendar Chandra

2012-08-01

Full Text Available Wireless access is increasingly ubiquitous while mobile devices that use them are resource rich. These trends allow wireless users to collaborate with each other. We investigate various group communication paradigms that underly collaboration applications. We synthesize durations when members collaborate using wireless device availability traces. Wireless users operate from a variety of locations. Hence, we analyzed the behavior of wireless users in universities, corporations, conference venues, and city-wide hotspots. We show that the availability durations are longer in corporations followed by university and then in hotspots. The number of simultaneously available wireless users is small in all the scenarios. The session lengths are becoming smaller while the durations between sessions are becoming larger. We observed user churn in all the scenarios. We show that synchronous mechanisms require less effort to maintain update synchronicity among the group members. However, distributed mechanisms require a large number of replicas in order to propagate updates among the users. For asynchronous mechanisms, we show that pull-based mechanisms naturally randomize the times when updates are propagated and thus achieve better performance than push based mechanisms.We develop an adaptive approach that customizes the update frequency using the last session duration and show that this mechanism exhibits good performance when the required update frequency intervals are large. We also show that for a given number of gossips, it is preferable to propagate updates to all available nodes rather than increasing the frequency while correspondingly reducing the number of nodes to propagate updates.We develop a middleware to illustrate the practicality of our approach.

Advanced routing protocols for wireless networks

CERN Document Server

Campista , Miguel Elias Mitre

2014-01-01

This text introduces the principles of routing protocols and metrics as they affect wireless networking environments, specifically in urban areas. Timely because of the recent rise in small city life, this topic includes the consideration of ad hoc, mesh, vehicular, sensor, and delay tolerant networks. These approaches are each unique, and author Miguel Mitre Campista provides a thorough, but accessible, explanation of their individual characteristics for engineers, computer scientists, IT professionals, and curious Internet users.

Real-time 2.5  Gbit/s spatial circuit switching on W-band wireless links

DEFF Research Database (Denmark)

Rodríguez, Sebastián; Morales Vicente, Alvaro; Gallardo, Omar

2017-01-01

A spatial circuit switching system based on a beam steering application for W-band wireless links is proposed and experimentally demonstrated. The system enables two simultaneous transmissions of a 2.5 Gbit∕s data signal over a carrier of 81 GHz, while allowing the receiver to dynamically switch...... between them. The performance of the system is tested with the real-time measurements of the BER, achieving values below the FEC limit for 7% of overhead and serving to prove the viability of wireless spatial circuit switching in the next generation of wireless access networks....

An Overview of Vertical Handoff Decision Algorithms in NGWNs and a new Scheme for Providing Optimized Performance in Heterogeneous Wireless Networks

Directory of Open Access Journals (Sweden)

Ionut BOSOANCA

2011-01-01

Full Text Available Because the increasingly development and use of wireless networks and mobile technologies, was implemented the idea that users of mobile terminals must have access in different wireless networks simultaneously. Therefore one of the main interest points of Next Generation Wireless Networks (NGWNs, refers to the ability to support wireless network access equipment to ensure a high rate of services between different wireless networks. To solve these problems it was necessary to have decision algorithms to decide for each user of mobile terminal, which is the best network at some point, for a service or a specific application that the user needs. Therefore to make these things, different algorithms use the vertical handoff technique. Below are presented a series of algorithms based on vertical handoff technique with a classification of the different existing vertical handoff decision strategies, which tries to solve these issues of wireless network selection at a given time for a specific application of an user. Based on our synthesis on vertical handoff decision strategies given below, we build our strategy based on solutions presented below, taking the most interesting aspect of each one.

Spatial Air Index Based on Largest Empty Rectangles for Non-Flat Wireless Broadcast in Pervasive Computing

Directory of Open Access Journals (Sweden)

Jun-Hong Shen

2016-11-01

Full Text Available In pervasive computing, location-based services (LBSs are valuable for mobile clients based on their current locations. LBSs use spatial window queries to enable useful applications for mobile clients. Based on skewed access patterns of mobile clients, non-flat wireless broadcast has been shown to efficiently disseminate spatial objects to mobile clients. In this paper, we consider a scenario in which spatial objects are broadcast to mobile clients over a wireless channel in a non-flat broadcast manner to process window queries. For such a scenario, we propose an efficient spatial air index method to handle window query access in non-flat wireless broadcast environments. The concept of largest empty rectangles is used to avoid unnecessary examination of the broadcast content, thus reducing the processing time for window queries. Simulation results show that the proposed spatial air index method outperforms the existing methods under various settings.

A Middleware Solution for Wireless IoT Applications in Sparse Smart Cities

Science.gov (United States)

Lanzone, Stefano; Riberto, Giulio; Stefanelli, Cesare; Tortonesi, Mauro

2017-01-01

The spread of off-the-shelf mobile devices equipped with multiple wireless interfaces together with sophisticated sensors is paving the way to novel wireless Internet of Things (IoT) environments, characterized by multi-hop infrastructure-less wireless networks where devices carried by users act as sensors/actuators as well as network nodes. In particular, the paper presents Real Ad-hoc Multi-hop Peer-to peer-Wireless IoT Application (RAMP-WIA), a novel solution that facilitates the development, deployment, and management of applications in sparse Smart City environments, characterized by users willing to collaborate by allowing new applications to be deployed on their smartphones to remotely monitor and control fixed/mobile devices. RAMP-WIA allows users to dynamically configure single-hop wireless links, to manage opportunistically multi-hop packet dispatching considering that the network topology (together with the availability of sensors and actuators) may abruptly change, to actuate reliably sensor nodes specifically considering that only part of them could be actually reachable in a timely manner, and to upgrade dynamically the nodes through over-the-air distribution of new software components. The paper also reports the performance of RAMP-WIA on simple but realistic cases of small-scale deployment scenarios with off-the-shelf Android smartphones and Raspberry Pi devices; these results show not only the feasibility and soundness of the proposed approach, but also the efficiency of the middleware implemented when deployed on real testbeds. PMID:29099745

A Middleware Solution for Wireless IoT Applications in Sparse Smart Cities.

Science.gov (United States)

Bellavista, Paolo; Giannelli, Carlo; Lanzone, Stefano; Riberto, Giulio; Stefanelli, Cesare; Tortonesi, Mauro

2017-11-03

The spread of off-the-shelf mobile devices equipped with multiple wireless interfaces together with sophisticated sensors is paving the way to novel wireless Internet of Things (IoT) environments, characterized by multi-hop infrastructure-less wireless networks where devices carried by users act as sensors/actuators as well as network nodes. In particular, the paper presents Real Ad-hoc Multi-hop Peer-to peer-Wireless IoT Application (RAMP-WIA), a novel solution that facilitates the development, deployment, and management of applications in sparse Smart City environments, characterized by users willing to collaborate by allowing new applications to be deployed on their smartphones to remotely monitor and control fixed/mobile devices. RAMP-WIA allows users to dynamically configure single-hop wireless links, to manage opportunistically multi-hop packet dispatching considering that the network topology (together with the availability of sensors and actuators) may abruptly change, to actuate reliably sensor nodes specifically considering that only part of them could be actually reachable in a timely manner, and to upgrade dynamically the nodes through over-the-air distribution of new software components. The paper also reports the performance of RAMP-WIA on simple but realistic cases of small-scale deployment scenarios with off-the-shelf Android smartphones and Raspberry Pi devices; these results show not only the feasibility and soundness of the proposed approach, but also the efficiency of the middleware implemented when deployed on real testbeds.

A Middleware Solution for Wireless IoT Applications in Sparse Smart Cities

Directory of Open Access Journals (Sweden)

Paolo Bellavista

2017-11-01

Full Text Available The spread of off-the-shelf mobile devices equipped with multiple wireless interfaces together with sophisticated sensors is paving the way to novel wireless Internet of Things (IoT environments, characterized by multi-hop infrastructure-less wireless networks where devices carried by users act as sensors/actuators as well as network nodes. In particular, the paper presents Real Ad-hoc Multi-hop Peer-to peer-Wireless IoT Application (RAMP-WIA, a novel solution that facilitates the development, deployment, and management of applications in sparse Smart City environments, characterized by users willing to collaborate by allowing new applications to be deployed on their smartphones to remotely monitor and control fixed/mobile devices. RAMP-WIA allows users to dynamically configure single-hop wireless links, to manage opportunistically multi-hop packet dispatching considering that the network topology (together with the availability of sensors and actuators may abruptly change, to actuate reliably sensor nodes specifically considering that only part of them could be actually reachable in a timely manner, and to upgrade dynamically the nodes through over-the-air distribution of new software components. The paper also reports the performance of RAMP-WIA on simple but realistic cases of small-scale deployment scenarios with off-the-shelf Android smartphones and Raspberry Pi devices; these results show not only the feasibility and soundness of the proposed approach, but also the efficiency of the middleware implemented when deployed on real testbeds.

Securing While Sampling in Wireless Body Area Networks With Application to Electrocardiography.

Science.gov (United States)

Dautov, Ruslan; Tsouri, Gill R

2016-01-01

Stringent resource constraints and broadcast transmission in wireless body area network raise serious security concerns when employed in biomedical applications. Protecting data transmission where any minor alteration is potentially harmful is of significant importance in healthcare. Traditional security methods based on public or private key infrastructure require considerable memory and computational resources, and present an implementation obstacle in compact sensor nodes. This paper proposes a lightweight encryption framework augmenting compressed sensing with wireless physical layer security. Augmenting compressed sensing to secure information is based on the use of the measurement matrix as an encryption key, and allows for incorporating security in addition to compression at the time of sampling an analog signal. The proposed approach eliminates the need for a separate encryption algorithm, as well as the predeployment of a key thereby conserving sensor node's limited resources. The proposed framework is evaluated using analysis, simulation, and experimentation applied to a wireless electrocardiogram setup consisting of a sensor node, an access point, and an eavesdropper performing a proximity attack. Results show that legitimate communication is reliable and secure given that the eavesdropper is located at a reasonable distance from the sensor node and the access point.

Survey on Cloud Radio Access Network

Directory of Open Access Journals (Sweden)

Reeta Chhatani

2016-01-01

Full Text Available The existing wireless network will face the challenge of data tsunami in the near future. Densification of network will deal huge data traffic but will increase the interferences and network cost. At the same time, the existing wireless network is underutilized due to dynamic traffic. To deal with this adverse scenario, a change in the current network architecture is required. Based on virtualization, Cloud Radio Access Network (CRAN was proposed for wireless network. In CRAN the functionality of base station will be distributed into base band unit (BBU and remote radio heads (RRH which will achieve benefits of centralization. This paper presents a survey on CRAN centring on optimized resource allocation, energy efficiency and throughput maximization under fronthaul capacity. The existing solution and future opportunities in CRAN are also summarized.

GCF: Green Conflict Free TDMA Scheduling for Wireless Sensor Network

DEFF Research Database (Denmark)

Pawar, Pranav M.; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

2012-01-01

The last few years have seen the promising growth in the application of wireless sensor networks (WSNs). The contribution of this paper is on a cluster-based time division multiple access (TDMA) scheduling algorithm to improve the performance of WSN applications in terms of energy efficiency, delay...

SECURITY IN THE ERA OF MOBILE WIRELESS ENTERPRISES

Directory of Open Access Journals (Sweden)

STEGĂROIU CARINA-ELENA

2014-02-01

Full Text Available In modern times, the mobility of people and data are becoming essential to business. An important role in this development is played by wireless technology, but the risks to users of wireless technology have increased as the service has become more popular. As mobility and the use of smaller, personal devices increases, it is obvious that the security must be implemented as close to the source as possible, meaning in all end devices, but such solutions are difficult to deploy and very hard to manage. Wireless security is just an aspect of computer security, however organizations may be particularly vulnerable to security breaches. There are effective countermeasures (like disabling open switchports during switch configuration and VLAN configuration to limit network access that are available to protect both the network and the information it contains, but such countermeasures must be applied uniformly to all network devices. Consequently, a security policy must be described and written down to allow managers as well as technicians to react correctly to undesired circumstances

Hand Gesture Based Wireless Robotic Arm Control for Agricultural Applications

Science.gov (United States)

Kannan Megalingam, Rajesh; Bandhyopadhyay, Shiva; Vamsy Vivek, Gedela; Juned Rahi, Muhammad

2017-08-01

One of the major challenges in agriculture is harvesting. It is very hard and sometimes even unsafe for workers to go to each plant and pluck fruits. Robotic systems are increasingly combined with new technologies to automate or semi automate labour intensive work, such as e.g. grape harvesting. In this work we propose a semi-automatic method for aid in harvesting fruits and hence increase productivity per man hour. A robotic arm fixed to a rover roams in the in orchard and the user can control it remotely using the hand glove fixed with various sensors. These sensors can position the robotic arm remotely to harvest the fruits. In this paper we discuss the design of hand glove fixed with various sensors, design of 4 DoF robotic arm and the wireless control interface. In addition the setup of the system and the testing and evaluation under lab conditions are also presented in this paper.

QoS Support Polling Scheme for Multimedia Traffic in Wireless LAN MAC Protocol

Institute of Scientific and Technical Information of China (English)

YANG Zhijun; ZHAO Dongfeng

2008-01-01

Quality of service (QoS) support is a key attribute for multimedia traffic including video, voice, and data in wireless local area networks (LANs) but is limited in 802.11-based wireless LANs. A polling-based scheme called the point coordination function (PCF) was developed for 802.11 LANs to support the trans-mission of multimedia traffic. However, the PCF is not able to meet the desired practical traffic differentiation requirements for real-time data. This paper describes a QoS support polling scheme based on the IEEE 802.11 medium access control (MAC) protocol. The scheme uses a two-level polling mechanism with the QoS classes differentiated by two different access policies. Stations with higher priority traffic such as key or real-time data form the first level and can access the common channel through an exhaustive access policy. Other stations with lower priority traffic form the second level and can access the channel through a gated access policy. A system model based on imbedded Markov chain theory and a generation function were setup to explicitly analyze the mean information packet waiting time of the two-level polling scheme. Theo-retical and simulation results show that the new scheme efficiently differentiates services to guarantee better QoS and system stability.

On Throughput Improvement of Wireless Ad Hoc Networks with Hidden Nodes

Science.gov (United States)

Choi, Hong-Seok; Lim, Jong-Tae

In this letter, we present the throughput analysis of the wireless ad hoc networks based on the IEEE 802.11 MAC (Medium Access Control). Especially, our analysis includes the case with the hidden node problem so that it can be applied to the multi-hop networks. In addition, we suggest a new channel access control algorithm to maximize the network throughput and show the usefulness of the proposed algorithm through simulations.

Multi-Channel Multi-Radio Using 802.11 Based Media Access for Sink Nodes in Wireless Sensor Networks

OpenAIRE

Campbell, Carlene E.-A.; Khan, Shafiullah; Singh, Dhananjay; Loo, Kok-Keong

2011-01-01

The next generation surveillance and multimedia systems will become increasingly deployed as wireless sensor networks in order to monitor parks, public places and for business usage. The convergence of data and telecommunication over IP-based networks has paved the way for wireless networks. Functions are becoming more intertwined by the compelling force of innovation and technology. For example, many closed-circuit TV premises surveillance systems now rely on transmitting their images and da...

Cost-effective hybrid RF/FSO backhaul solution for next generation wireless systems

KAUST Repository

Dahrouj, Hayssam; Douik, Ahmed; Rayal, Frank; Al-Naffouri, Tareq Y.; Alouini, Mohamed-Slim

2015-01-01

The rapid pace of demand for mobile data services and the limited supply of capacity in the current wireless access networks infrastructure are leading network operators to increase the density of base station deployments to improve network

A Priority-Based Adaptive MAC Protocol for Wireless Body Area Networks

Directory of Open Access Journals (Sweden)

Sabin Bhandari

2016-03-01

Full Text Available In wireless body area networks (WBANs, various sensors and actuators are placed on/inside the human body and connected wirelessly. WBANs have specific requirements for healthcare and medical applications, hence, standard protocols like the IEEE 802.15.4 cannot fulfill all the requirements. Consequently, many medium access control (MAC protocols, mostly derived from the IEEE 802.15.4 superframe structure, have been studied. Nevertheless, they do not support a differentiated quality of service (QoS for the various forms of traffic coexisting in a WBAN. In particular, a QoS-aware MAC protocol is essential for WBANs operating in the unlicensed Industrial, Scientific, and Medical (ISM bands, because different wireless services like Bluetooth, WiFi, and Zigbee may coexist there and cause severe interference. In this paper, we propose a priority-based adaptive MAC (PA-MAC protocol for WBANs in unlicensed bands, which allocates time slots dynamically, based on the traffic priority. Further, multiple channels are effectively utilized to reduce access delays in a WBAN, in the presence of coexisting systems. Our performance evaluation results show that the proposed PA-MAC outperforms the IEEE 802.15.4 MAC and the conventional priority-based MAC in terms of the average transmission time, throughput, energy consumption, and data collision ratio.

A Priority-Based Adaptive MAC Protocol for Wireless Body Area Networks.

Science.gov (United States)

Bhandari, Sabin; Moh, Sangman

2016-03-18

In wireless body area networks (WBANs), various sensors and actuators are placed on/inside the human body and connected wirelessly. WBANs have specific requirements for healthcare and medical applications, hence, standard protocols like the IEEE 802.15.4 cannot fulfill all the requirements. Consequently, many medium access control (MAC) protocols, mostly derived from the IEEE 802.15.4 superframe structure, have been studied. Nevertheless, they do not support a differentiated quality of service (QoS) for the various forms of traffic coexisting in a WBAN. In particular, a QoS-aware MAC protocol is essential for WBANs operating in the unlicensed Industrial, Scientific, and Medical (ISM) bands, because different wireless services like Bluetooth, WiFi, and Zigbee may coexist there and cause severe interference. In this paper, we propose a priority-based adaptive MAC (PA-MAC) protocol for WBANs in unlicensed bands, which allocates time slots dynamically, based on the traffic priority. Further, multiple channels are effectively utilized to reduce access delays in a WBAN, in the presence of coexisting systems. Our performance evaluation results show that the proposed PA-MAC outperforms the IEEE 802.15.4 MAC and the conventional priority-based MAC in terms of the average transmission time, throughput, energy consumption, and data collision ratio.

REAL TIME ANALYSIS OF WIRELESS CONTROLLER AREA NETWORK

Directory of Open Access Journals (Sweden)

Gerardine Immaculate Mary

2014-09-01

Full Text Available It is widely known that Control Area Networks (CAN are used in real-time, distributed and parallel processing which cover manufacture plants, humanoid robots, networking fields, etc., In applications where wireless conditions are encountered it is convenient to continue the exchange of CAN frames within the Wireless CAN (WCAN. The WCAN considered in this research is based on wireless token ring protocol (WTRP; a MAC protocol for wireless networks to reduce the number of retransmissions due to collision and the wired counterpart CAN attribute on message based communication. WCAN uses token frame method to provide channel access to the nodes in the system. This method allow all the nodes to share common broadcast channel by taken turns in transmitting upon receiving the token frame which is circulating within the network for specified amount of time. This method provides high throughput in bounded latency environment, consistent and predictable delays and good packet delivery ratio. The most important factor to consider when evaluating a control network is the end-to-end time delay between sensors, controllers, and actuators. The correct operation of a control system depends on the timeliness of the data coming over the network, and thus, a control network should be able to guarantee message delivery within a bounded transmission time. The proposed WCAN is modeled and simulated using QualNet, and its average end to end delay and packet delivery ratio (PDR are calculated. The parameters boundaries of WCAN are evaluated to guarantee a maximum throughput and a minimum latency time, in the case of wireless communications, precisely WCAN.

Reactive and adaptive monitoring to secure aggregation in wireless sensor networks

NARCIS (Netherlands)

Labraoui, Nabila; Gueroui, Mourad; Aliouat, Makhlouf; Petit, Jonathan

Data aggregation is considered as one of the fundamental distributed data processing procedures for saving the energy and minimizing the medium access layer contention in wireless sensor networks. However, sensor networks are likely to be deployed in an untrusted environment, which make them

Energy Harvesting - Wireless Sensor Networks for Indoors Applications Using IEEE 802.11

DEFF Research Database (Denmark)

Fafoutis, Xenofon; Sørensen, Thomas; Madsen, Jan

2014-01-01

The paper investigates the feasibility of using IEEE 802.11 in energy harvesting low-power sensing applications. The investigation is based on a prototype carbon dioxide sensor node that is powered by artificial indoors light. The wireless communication module of the sensor node is based on the RTX......4100 module. RTX4100 incorporates a wireless protocol that duty-cycles the radio while being compatible with IEEE 802.11 access points. The presented experiments demonstrate sustainable operation but indicate a trade-off between the benefits of using IEEE 802.11 in energy harvesting applications...

Optimizing Energy and Modulation Selection in Multi-Resolution Modulation For Wireless Video Broadcast/Multicast

KAUST Repository

She, James

2009-11-01

Emerging technologies in Broadband Wireless Access (BWA) networks and video coding have enabled high-quality wireless video broadcast/multicast services in metropolitan areas. Joint source-channel coded wireless transmission, especially using hierarchical/superposition coded modulation at the channel, is recognized as an effective and scalable approach to increase the system scalability while tackling the multi-user channel diversity problem. The power allocation and modulation selection problem, however, is subject to a high computational complexity due to the nonlinear formulation and huge solution space. This paper introduces a dynamic programming framework with conditioned parsing, which significantly reduces the search space. The optimized result is further verified with experiments using real video content. The proposed approach effectively serves as a generalized and practical optimization framework that can gauge and optimize a scalable wireless video broadcast/multicast based on multi-resolution modulation in any BWA network.

Optimizing Energy and Modulation Selection in Multi-Resolution Modulation For Wireless Video Broadcast/Multicast

KAUST Repository

She, James; Ho, Pin-Han; Shihada, Basem

2009-01-01

Emerging technologies in Broadband Wireless Access (BWA) networks and video coding have enabled high-quality wireless video broadcast/multicast services in metropolitan areas. Joint source-channel coded wireless transmission, especially using hierarchical/superposition coded modulation at the channel, is recognized as an effective and scalable approach to increase the system scalability while tackling the multi-user channel diversity problem. The power allocation and modulation selection problem, however, is subject to a high computational complexity due to the nonlinear formulation and huge solution space. This paper introduces a dynamic programming framework with conditioned parsing, which significantly reduces the search space. The optimized result is further verified with experiments using real video content. The proposed approach effectively serves as a generalized and practical optimization framework that can gauge and optimize a scalable wireless video broadcast/multicast based on multi-resolution modulation in any BWA network.

ENERGY EFFICIENT ROUTING PROTOCOLS FOR WIRELESS AD HOC NETWORKS – A SURVEY

Directory of Open Access Journals (Sweden)

K. Sankar

2012-06-01

Full Text Available Reducing energy consumption, primarily with the goal of extending the lifetime of battery-powered devices, has emerged as a fundamental challenge in wireless communication. The performance of the medium access control (MAC scheme not only has a fairly significant end-result on the behaviour of the routing approach employed, but also on the energy consumption of the wireless network interface card (NIC. We investigate the inadequacies of the MAC schemes designed for ad hoc wireless networks in the context of power awareness herein. The topology changes due to uncontrollable factors such as node mobility, weather, interference, noise, as well as on controllable parameters such as transmission power and antenna direction results in significant amount of energy loss. Controlling rapid topology changes by minimizing the maximum transmission power used in ad hoc wireless networks, while still maintaining networks connectivity can prolong battery life and hence network lifetime considerably. In addition, we systematically explore the potential energy consumption pitfalls of non–power-based and power based routing schemes. We suggest a thorough energy-based performance survey of energy aware routing protocols for wireless mobile ad-hoc networks. We also present the statistical performance metrics measured by our simulations.

A wireless smart sensor network for automated monitoring of cable tension

International Nuclear Information System (INIS)

Sim, Sung-Han; Cho, Soojin; Li, Jian; Jo, Hongki; Park, Jong-Woong; Jung, Hyung-Jo; Spencer Jr, Billie F

2014-01-01

As cables are primary load carrying members in cable-stayed bridges, monitoring the tension forces of the cables provides valuable information regarding structural soundness. Incorporating wireless smart sensors with vibration-based tension estimation methods provides an efficient means of autonomous long-term monitoring of cable tensions. This study develops a wireless cable tension monitoring system using MEMSIC’s Imote2 smart sensors. The monitoring system features autonomous operation, sustainable energy harvesting and power consumption, and remote access using the internet. To obtain the tension force, an in-network data processing strategy associated with the vibration-based tension estimation method is implemented on the Imote2-based sensor network, significantly reducing the wireless data transmission and the power consumption. The proposed monitoring system has been deployed and validated on the Jindo Bridge, a cable-stayed bridge located in South Korea. (paper)

A wireless smart sensor network for automated monitoring of cable tension

Science.gov (United States)

Sim, Sung-Han; Li, Jian; Jo, Hongki; Park, Jong-Woong; Cho, Soojin; Spencer, Billie F., Jr.; Jung, Hyung-Jo

2014-02-01

As cables are primary load carrying members in cable-stayed bridges, monitoring the tension forces of the cables provides valuable information regarding structural soundness. Incorporating wireless smart sensors with vibration-based tension estimation methods provides an efficient means of autonomous long-term monitoring of cable tensions. This study develops a wireless cable tension monitoring system using MEMSIC’s Imote2 smart sensors. The monitoring system features autonomous operation, sustainable energy harvesting and power consumption, and remote access using the internet. To obtain the tension force, an in-network data processing strategy associated with the vibration-based tension estimation method is implemented on the Imote2-based sensor network, significantly reducing the wireless data transmission and the power consumption. The proposed monitoring system has been deployed and validated on the Jindo Bridge, a cable-stayed bridge located in South Korea.

Compact wireless control network protocol with fast path switching

Directory of Open Access Journals (Sweden)

Yasutaka Kawamoto

2017-08-01

Full Text Available Sensor network protocol stacks require the addition or adjustment of functions based on customer requirements. Sensor network protocols that require low delay and low packet error rate (PER, such as wireless control networks, often adopt time division multiple access (TDMA. However, it is difficult to add or adjust functions in protocol stacks that use TDMA methods. Therefore, to add or adjust functions easily, we propose NES-SOURCE, a compact wireless control network protocol with a fast path-switching function. NES-SOURCE is implemented using carrier sense multiple access/collision avoidance (CSMA/CA rather than TDMA. Wireless control networks that use TDMA prevent communication failure by duplicating the communication path. If CSMA/CA networks use duplicate paths, collisions occur frequently, and communication will fail. NES-SOURCE switches paths quickly when communication fails, which reduces the effect of communication failures. Since NES-SOURCE is implemented using CSMA/CA rather than TDMA, the implementation scale is less than one-half that of existing network stacks. Furthermore, since NES-SOURCE’s code complexity is low, functions can be added or adjusted easily and quickly. Communication failures occur owing to changes in the communication environment and collisions. Experimental results demonstrate that the proposed NES-SOURCE’s path-switching function reduces the amount of communication failures when the communication environment changes owing to human movement and others. Furthermore, we clarify the relationships among the probability of a changing communication environment, the collision occurrence rate, and the PER of NES-SOURCE.

Implementation of Wireless Communications Systems on FPGA-Based Platforms

Directory of Open Access Journals (Sweden)

Voros NS

2007-01-01

Full Text Available Wireless communications are a very popular application domain. The efficient implementation of their components (access points and mobile terminals/network interface cards in terms of hardware cost and design time is of great importance. This paper describes the design and implementation of the HIPERLAN/2 WLAN system on a platform including general purpose microprocessors and FPGAs. Detailed implementation results (performance, code size, and FPGA resources utilization are presented. The main goal of the design case presented is to provide insight into the design aspects of a complex system based on FPGAs. The results prove that an implementation based on microprocessors and FPGAs is adequate for the access point part of the system where the expected volumes are rather small. At the same time, such an implementation serves as a prototyping of an integrated implementation (System-on-Chip, which is necessary for the mobile terminals of a HIPERLAN/2 system. Finally, firmware upgrades were developed allowing the implementation of an outdoor wireless communication system on the same platform.

The Wireless ATM Architecture

Directory of Open Access Journals (Sweden)

R. Palitefka

1998-06-01

Full Text Available An overview of the proposed wireless ATM structure is provided. Wireless communication have been developed to a level where offered services can now be extended beyond voice and data. There are already wireless LANs, cordless systems offering data services and mobile data. Wireless LAN systems are basically planned for local, on-promises and in-house networking providing short distance radio or infrared links between computer system. The main challenge of wireless ATM is to harmonise the development of broadband wireless system with service B -ISDN/ATM and ATM LANs, and offer multimedia multiservice features for the support of time-sensitive voice communication, video, desktop multimedia applications, and LAN data traffic for the wireless user.

Analysis of Blocking Rate and Bandwidth Usage of Mobile IPTV Services in Wireless Cellular Networks

Directory of Open Access Journals (Sweden)

Mingfu Li

2014-01-01

Full Text Available Mobile IPTV services over wireless cellular networks become more and more popular, owing to the significant growth in access bandwidth of wireless cellular networks such as 3G/4G and WiMAX. However, the spectrum resources of wireless cellular networks is rare. How to enhance the spectral efficiency of mobile networks becomes an important issue. Unicast, broadcast, and multicast are the most important transport schemes for offering mobile IPTV services over wireless cellular networks. Therefore, bandwidth usages and blocking rates of unicast, broadcast, and multicast IPTV services were analyzed and compared in this paper. Simulations were also conducted to validate the analytical results. Numerical results demonstrate that the presented analysis is correct, and multicast scheme achieves the best bandwidth usage and blocking rate performance, relative to the other two schemes.

Analysis of blocking rate and bandwidth usage of mobile IPTV services in wireless cellular networks.

Science.gov (United States)

Li, Mingfu

2014-01-01

Mobile IPTV services over wireless cellular networks become more and more popular, owing to the significant growth in access bandwidth of wireless cellular networks such as 3G/4G and WiMAX. However, the spectrum resources of wireless cellular networks is rare. How to enhance the spectral efficiency of mobile networks becomes an important issue. Unicast, broadcast, and multicast are the most important transport schemes for offering mobile IPTV services over wireless cellular networks. Therefore, bandwidth usages and blocking rates of unicast, broadcast, and multicast IPTV services were analyzed and compared in this paper. Simulations were also conducted to validate the analytical results. Numerical results demonstrate that the presented analysis is correct, and multicast scheme achieves the best bandwidth usage and blocking rate performance, relative to the other two schemes.

Ultra Secure High Reliability Wireless Radiation Monitor

International Nuclear Information System (INIS)

Cordaro, J.; Shull, D.; Farrar, M.; Reeves, G.

2011-01-01

Radiation monitoring in nuclear facilities is essential to safe operation of the equipment as well as protecting personnel. In specific, typical air monitoring of radioactive gases or particulate involves complex systems of valves, pumps, piping and electronics. The challenge is to measure a representative sample in areas that are radioactively contaminated. Running cables and piping to these locations is very expensive due to the containment requirements. Penetration into and out of an airborne or containment area is complex and costly. The process rooms are built with thick rebar-enforced concrete walls with glove box containment chambers inside. Figure 1 shows high temperature radiation resistance cabling entering the top of a typical glove box. In some case, the entire processing area must be contained in a 'hot cell' where the only access into the chamber is via manipulators. An example is shown in Figure 2. A short range wireless network provides an ideal communication link for transmitting the data from the radiation sensor to a 'clean area', or area absent of any radiation fields or radioactive contamination. Radiation monitoring systems that protect personnel and equipment must meet stringent codes and standards due to the consequences of failure. At first glance a wired system would seem more desirable. Concerns with wireless communication include latency, jamming, spoofing, man in the middle attacks, and hacking. The Department of Energy's Savannah River National Laboratory (SRNL) has developed a prototype wireless radiation air monitoring system that address many of the concerns with wireless and allows quick deployment in radiation and contamination areas. It is stand alone and only requires a standard 120 VAC, 60 Hz power source. It is designed to be mounted or portable. The wireless link uses a National Security Agency (NSA) Suite B compliant wireless network from Fortress Technologies that is considered robust enough to be used for classified data

ULTRA SECURE HIGH RELIABILITY WIRELESS RADIATION MONITOR

Energy Technology Data Exchange (ETDEWEB)

Cordaro, J.; Shull, D.; Farrar, M.; Reeves, G.

2011-08-03

Radiation monitoring in nuclear facilities is essential to safe operation of the equipment as well as protecting personnel. In specific, typical air monitoring of radioactive gases or particulate involves complex systems of valves, pumps, piping and electronics. The challenge is to measure a representative sample in areas that are radioactively contaminated. Running cables and piping to these locations is very expensive due to the containment requirements. Penetration into and out of an airborne or containment area is complex and costly. The process rooms are built with thick rebar-enforced concrete walls with glove box containment chambers inside. Figure 1 shows high temperature radiation resistance cabling entering the top of a typical glove box. In some case, the entire processing area must be contained in a 'hot cell' where the only access into the chamber is via manipulators. An example is shown in Figure 2. A short range wireless network provides an ideal communication link for transmitting the data from the radiation sensor to a 'clean area', or area absent of any radiation fields or radioactive contamination. Radiation monitoring systems that protect personnel and equipment must meet stringent codes and standards due to the consequences of failure. At first glance a wired system would seem more desirable. Concerns with wireless communication include latency, jamming, spoofing, man in the middle attacks, and hacking. The Department of Energy's Savannah River National Laboratory (SRNL) has developed a prototype wireless radiation air monitoring system that address many of the concerns with wireless and allows quick deployment in radiation and contamination areas. It is stand alone and only requires a standard 120 VAC, 60 Hz power source. It is designed to be mounted or portable. The wireless link uses a National Security Agency (NSA) Suite B compliant wireless network from Fortress Technologies that is considered robust enough to be

An Ultraviolet Optical Wireless Sensor Network in Multi-scattering Channels

Science.gov (United States)

Kedar, Debbie; Arnon, Shlomi

2006-10-01

Networks of wirelessly communicating sensors are a promising technology for future data-gathering systems in both civilian and military applications including medical and environmental monitoring and surveillance, home security and industry. Optical wireless communication is a potential solution for the links, particularly thanks to the small and lightweight hardware and low power consumption. A noteworthy feature of optical wireless communication at ultraviolet wavelengths is that scattering of radiation by atmospheric particles is significant, so that the backscattering of light by these particles can function as a vehicle of communication as if numerous tiny reflecting mirrors were placed in the atmosphere. Also, almost no solar radiation penetrates the atmosphere in this spectral band, which is hence called the solar blind ultraviolet spectrum, so that very large field-of-view receivers can be used. In this paper we present a model of a non-line-of-sight (NLOS) optical wireless sensor network operating in the solar blind ultraviolet spectrum. The system feasibility is evaluated and found to facilitate miniature operational sensor networks. The problem of multi-access interference is addressed and the possibility of overcoming it using WDM diversity methods is investigated.

OPNET Modeler simulations of performance for multi nodes wireless systems

Directory of Open Access Journals (Sweden)

Krupanek Beata

2016-01-01

Full Text Available Paper presents a study under the Quality of Service in modern wireless sensor networks. Such a networks are characterized by small amount of data transmitted in fixed periods. Very often this data must by transmitted in real time so data transmission delays should be well known. This article shows multimode network simulated in packet OPNET Modeler. Also nowadays the quality of services is very important especially in multi-nodes systems such a home automation or measurement systems.

End-to-end Configuration of Wireless Realtime Communication over Heterogeneous Protocols

DEFF Research Database (Denmark)

Malinowsky, B.; Grønbæk, Jesper; Schwefel, Hans-Peter

2015-01-01

This paper describes a wireless real-time communication system design using two Time Division Multiple Access (TDMA) protocols. Messages are subject to prioritization and queuing. For this interoperation scenario, we show a method for end-to-end configuration of protocols and queue sizes. Such co...

Access Point Backhaul Resource Aggregation as a Many-to-One Matching Game in Wireless Local Area Networks

Directory of Open Access Journals (Sweden)

Kawther Hassine

2017-01-01

Full Text Available This paper studies backhaul bandwidth aggregation in the context of a wireless local area network composed of two different types of access points: those with spare backhaul capacity (which we term providers and those in shortage of it (beneficiaries; the aim is to transfer excess capacity from providers to beneficiaries. We model the system as a matching game with many-to-one setting wherein several providers can be matched to one beneficiary and adopt the so-called deferred acceptance algorithm to reach an optimal and stable solution. We consider two flavors, when the beneficiaries are limited in their resource demands and when they are not, and two scenarios, when resources are abundant and when they are scarce. Our results show that the many-to-one setting outperforms the one-to-one case in terms of overall throughput gain, resource usage, and individual beneficiaries satisfaction by up to 50%, whether resources are scarce or abundant. As of the limited versus nonlimited case, the former ensures more fair sharing of spectral resources and higher satisfaction percentage between beneficiaries.

Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

Science.gov (United States)

Razaque, Abdul; Elleithy, Khaled M.

2014-01-01

This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC) for wireless sensor networks (WSNs), which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols, BN-MAC reduces idle listening time, emissions, and collision handling at low cost at one-hop neighbor nodes and achieves high channel utilization under heavy network loads. BN-MAC is particularly designed for region-wise WSNs. Each region is controlled by a boarder node (BN), which is of paramount importance. The BN coordinates with the remaining nodes within and beyond the region. Unlike other hybrid MAC protocols, BN-MAC incorporates three promising models that further reduce the energy consumption, idle listening time, overhearing, and congestion to improve the throughput and reduce the latency. One of the models used with BN-MAC is automatic active and sleep (AAS), which reduces the ideal listening time. When nodes finish their monitoring process, AAS lets them automatically go into the sleep state to avoid the idle listening state. Another model used in BN-MAC is the intelligent decision-making (IDM) model, which helps the nodes sense the nature of the environment. Based on the nature of the environment, the nodes decide whether to use the active or passive mode. This decision power of the nodes further reduces energy consumption because the nodes turn off the radio of the transceiver in the passive mode. The third model is the least-distance smart neighboring search (LDSNS), which determines the shortest efficient path to the one-hop neighbor and also provides cross-layering support to handle the mobility of the nodes. The BN-MAC also incorporates a semi

Energy-efficient boarder node medium access control protocol for wireless sensor networks.

Science.gov (United States)

Razaque, Abdul; Elleithy, Khaled M

2014-03-12

This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC) for wireless sensor networks (WSNs), which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols, BN-MAC reduces idle listening time, emissions, and collision handling at low cost at one-hop neighbor nodes and achieves high channel utilization under heavy network loads. BN-MAC is particularly designed for region-wise WSNs. Each region is controlled by a boarder node (BN), which is of paramount importance. The BN coordinates with the remaining nodes within and beyond the region. Unlike other hybrid MAC protocols, BN-MAC incorporates three promising models that further reduce the energy consumption, idle listening time, overhearing, and congestion to improve the throughput and reduce the latency. One of the models used with BN-MAC is automatic active and sleep (AAS), which reduces the ideal listening time. When nodes finish their monitoring process, AAS lets them automatically go into the sleep state to avoid the idle listening state. Another model used in BN-MAC is the intelligent decision-making (IDM) model, which helps the nodes sense the nature of the environment. Based on the nature of the environment, the nodes decide whether to use the active or passive mode. This decision power of the nodes further reduces energy consumption because the nodes turn off the radio of the transceiver in the passive mode. The third model is the least-distance smart neighboring search (LDSNS), which determines the shortest efficient path to the one-hop neighbor and also provides cross-layering support to handle the mobility of the nodes. The BN-MAC also incorporates a semi

Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Abdul Razaque

2014-03-01

Full Text Available This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC for wireless sensor networks (WSNs, which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols, BN-MAC reduces idle listening time, emissions, and collision handling at low cost at one-hop neighbor nodes and achieves high channel utilization under heavy network loads. BN-MAC is particularly designed for region-wise WSNs. Each region is controlled by a boarder node (BN, which is of paramount importance. The BN coordinates with the remaining nodes within and beyond the region. Unlike other hybrid MAC protocols, BN-MAC incorporates three promising models that further reduce the energy consumption, idle listening time, overhearing, and congestion to improve the throughput and reduce the latency. One of the models used with BN-MAC is automatic active and sleep (AAS, which reduces the ideal listening time. When nodes finish their monitoring process, AAS lets them automatically go into the sleep state to avoid the idle listening state. Another model used in BN-MAC is the intelligent decision-making (IDM model, which helps the nodes sense the nature of the environment. Based on the nature of the environment, the nodes decide whether to use the active or passive mode. This decision power of the nodes further reduces energy consumption because the nodes turn off the radio of the transceiver in the passive mode. The third model is the least-distance smart neighboring search (LDSNS, which determines the shortest efficient path to the one-hop neighbor and also provides cross-layering support to handle the mobility of the nodes. The BN-MAC also incorporates a semi

Wireless Communication Technologies

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. Wireless Communication Technologies. Since 1999, the wireless LAN has experienced a tremendous growth. Reasons: Adoption of industry standards. Interoperability testing. The progress of wireless equipments to higher data rates. Rapid decrease in product ...

Worlds largest particle physics laboratory selects Proxim Wireless Mesh

CERN Multimedia

2007-01-01

"Proxim Wireless has announced that the European Organization for Nuclear Research (CERN), the world's largest particle physics laboratory and the birthplace of the World Wide Web, is using it's ORiNOCO AP-4000 mesh access points to extend the range of the laboratory's Wi-Fi network and to provide continuous monitoring of the lab's calorimeters" (1/2 page)

PRESSURE - WATER and Other Data from FIXED PLATFORM and Other Platforms From TOGA Area - Pacific (30 N to 30 S) from 19910409 to 19950508 (NODC Accession 9500137)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The current, temperature and wind data in this accession was collected over a four year period from 48 current meters fixed from 8 moorings as part of Equatorial...

Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling.

Science.gov (United States)

Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

2015-09-18

This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols.

Seals monitoring systems using wireless communications

International Nuclear Information System (INIS)

Hermand, Guillaume; Bertrand, Johan; Farhoud, Radwan; Suzuki, Kei; ETO, Jiro; Tanabe, Hiromi; Takamura, Hisashi; Suyama, Yasuhiro

2012-01-01

Document available in extended abstract form only. Wireless monitoring based on electromagnetic waves is a promising application for deep geological nuclear waste repositories. It should allow data transmission without installing wires across the various seals (disposal cell plugs, gallery plugs, shaft plugs). Developments of the wireless system (e.g. transmitter and receiver) are in progress in order to fit the repository requirements. A common research program has been elaborated by RWMC and Andra. The present work aims at developing the wireless monitoring technology to intermediate level waste (ILW) disposal facilities concept. In this concept, ILW packages will be emplaced in disposal cells with concrete liner. After the operational phase, the cells will be backfilled with sealing material. In practice, this work demonstrates the feasibility of adapting and optimizing the wireless transmission system for specific repository cases. After preliminary transmission studies, it was decided to make a representative test in situ of a wireless transmission through the clay from a sealed side to an accessible side of the repository. In order to reduce the attenuation of magnetic flux caused by steel components between the transmitter and the receiver, the receiving antenna is installed in a dedicated borehole (drilled from the accessible side). Two types of reception antennas have been designed. According to its coil orientation, type A antenna measures the electromagnetic wave perpendicular to the borehole axis. On the other hand, type B antenna with a coil set in-line with the tubular casing, measures the electromagnetic wave parallel to the borehole axis. The outside cylinder (pressure tight case) is made of PVC considering the attenuation of electromagnetic flux. According to the direction of electromagnetic flux and position of the boreholes in the final repository design, type A or type B will be chosen. For the 'representative' test, a borehole, TSF1002 has been

Household wireless electroencephalogram hat

Science.gov (United States)

Szu, Harold; Hsu, Charles; Moon, Gyu; Yamakawa, Takeshi; Tran, Binh

2012-06-01

We applied Compressive Sensing to design an affordable, convenient Brain Machine Interface (BMI) measuring the high spatial density, and real-time process of Electroencephalogram (EEG) brainwaves by a Smartphone. It is useful for therapeutic and mental health monitoring, learning disability biofeedback, handicap interfaces, and war gaming. Its spec is adequate for a biomedical laboratory, without the cables hanging over the head and tethered to a fixed computer terminal. Our improved the intrinsic signal to noise ratio (SNR) by using the non-uniform placement of the measuring electrodes to create the proximity of measurement to the source effect. We computing a spatiotemporal average the larger magnitude of EEG data centers in 0.3 second taking on tethered laboratory data, using fuzzy logic, and computing the inside brainwave sources, by Independent Component Analysis (ICA). Consequently, we can overlay them together by non-uniform electrode distribution enhancing the signal noise ratio and therefore the degree of sparseness by threshold. We overcame the conflicting requirements between a high spatial electrode density and precise temporal resolution (beyond Event Related Potential (ERP) P300 brainwave at 0.3 sec), and Smartphone wireless bottleneck of spatiotemporal throughput rate. Our main contribution in this paper is the quality and the speed of iterative compressed image recovery algorithm based on a Block Sparse Code (Baranuick et al, IEEE/IT 2008). As a result, we achieved real-time wireless dynamic measurement of EEG brainwaves, matching well with traditionally tethered high density EEG.

Dynamic sink assignment for efficient energy consumption in wireless sensor networks

KAUST Repository

Oikonomou, Konstantinos N.

2012-04-01

Efficient energy consumption is a challenging problem in wireless sensor networks (WSNs) and closely related to extending network lifetime. The usual way of tackling this issue for topologies with fixed link weight and fixed sink location, has been shown to be severely affected by the energy hole problem. In this paper, the energy consumption problem is initially studied for WSNs with fixed sink assignment and it is analytically shown that energy consumption is minimized when the sink is assigned to the node that is the solution of a suitably formulated 1-median problem. This motivates the introduction of a dynamic environment where link weights change based on the energy level and the aggregate traffic load of the adjacent nodes. Then, the sink is adaptively allowed to move among neighbor nodes, according to a scalable sink migration strategy. Simulation results support the analytical claims demonstrating energy consumption reduction and an additional network lifetime increment when migration is employed in the dynamic environment. © 2012 IEEE.

Transmit Power Optimisation in Wireless Network

Directory of Open Access Journals (Sweden)

Besnik Terziu

2011-09-01

Full Text Available Transmit power optimisation in wireless networks based on beamforming have emerged as a promising technique to enhance the spectrum efficiency of present and future wireless communication systems. The aim of this study is to minimise the access point power consumption in cellular networks while maintaining a targeted quality of service (QoS for the mobile terminals. In this study, the targeted quality of service is delivered to a mobile station by providing a desired level of Signal to Interference and Noise Ratio (SINR. Base-stations are coordinated across multiple cells in a multi-antenna beamforming system. This study focuses on a multi-cell multi-antenna downlink scenario where each mobile user is equipped with a single antenna, but where multiple mobile users may be active simultaneously in each cell and are separated via spatial multiplexing using beamforming. The design criteria is to minimize the total weighted transmitted power across the base-stations subject to SINR constraints at the mobile users. The main contribution of this study is to define an iterative algorithm that is capable of finding the joint optimal beamformers for all basestations, based on a correlation-based channel model, the full-correlation model. Among all correlated channel models, the correlated channel model used in this study is the most accurate, giving the best performance in terms of power consumption. The environment here in this study is chosen to be Non-Light of- Sight (NLOS condition, where a signal from a wireless transmitter passes several obstructions before arriving at a wireless receiver. Moreover there are many scatterers local to the mobile, and multiple reflections can occur among them before energy arrives at the mobile. The proposed algorithm is based on uplink-downlink duality using the Lagrangian duality theory. Time-Division Duplex (TDD is chosen as the platform for this study since it has been adopted to the latest technologies in Fourth

Software Defined Networks in Wireless Sensor Architectures

Directory of Open Access Journals (Sweden)

Jesús Antonio Puente Fernández

2018-03-01

Full Text Available Nowadays, different protocols coexist in Internet that provides services to users. Unfortunately, control decisions and distributed management make it hard to control networks. These problems result in an inefficient and unpredictable network behaviour. Software Defined Networks (SDN is a new concept of network architecture. It intends to be more flexible and to simplify the management in networks with respect to traditional architectures. Each of these aspects are possible because of the separation of control plane (controller and data plane (switches in network devices. OpenFlow is the most common protocol for SDN networks that provides the communication between control and data planes. Moreover, the advantage of decoupling control and data planes enables a quick evolution of protocols and also its deployment without replacing data plane switches. In this survey, we review the SDN technology and the OpenFlow protocol and their related works. Specifically, we describe some technologies as Wireless Sensor Networks and Wireless Cellular Networks and how SDN can be included within them in order to solve their challenges. We classify different solutions for each technology attending to the problem that is being fixed.

Fixing Accessibility Issues in Open-Source Teaching Repositories

Directory of Open Access Journals (Sweden)

Francisco Javier Díaz

2017-12-01

Full Text Available In the LINTI, New Information Technologies Research Laboratory at the Computer Science School, in the National University of La Plata, it is being developed a project that involves the integration of the repository, implemented using DSpace, with different tools and platforms used in academic tasks. Accessibility is a process that cuts across all software development stages, so when using a free software product it is important to evaluate it in order to correct faults if it´s necessary. This article describes a DSpace repository accessibility validation, using screen readers for manual test, automatic validation with software tools and experimental test with users with and without disabilities. The evaluation involves the proper basic functions and the implemented extensions. The original DSpace software was extended through the integration with different tools and platforms, such as Moodle LMS, the library management system called Meran, file management services like DropBox and GoogleDrive and the social network Facebook.  The tools used during accessibility evaluation were Examinator, Google ChromeVox and one entirely implemented in the LINTI, called SiMor. The experimental tests were made with blind and deaf persons, most of them college students. All the validation results are detailed using tables and graphs, where it can observe the measured values. It is also described the changes that was necessary to carry out in the repository to improve the user experience and ensure Web service accessibility.

Digital Predistortion of 75-110GHzW-Band Frequency Multiplier for Fiber Wireless Short Range Access Systems

DEFF Research Database (Denmark)

Zhao, Ying; Pang, Xiaodan; Deng, Lei

2011-01-01

We present a digital predistortion technique to effectively compensate high nonlinearity of a sextuple multiplier operating at 99.6GHz. An 18.9dB adjacent-channel power ratio (ACPR) improvement is guaranteed and a W-band fiber-wireless system is experimentally investigated.......We present a digital predistortion technique to effectively compensate high nonlinearity of a sextuple multiplier operating at 99.6GHz. An 18.9dB adjacent-channel power ratio (ACPR) improvement is guaranteed and a W-band fiber-wireless system is experimentally investigated....

Photonics-assisted wireless link based on mm-wave reconfigurable antennas

DEFF Research Database (Denmark)

Feliciano daCosta, Igor; Cerqueira Sodré, Arismar; Rodriguez Páez, Juan Sebastián

2017-01-01

The authors report a novel concept for photonics-assisted and broadband optical-wireless indoor networks based on optically-controlled reconfigurable antenna arrays (OCRAAs) and photonic down conversion (PDC) techniques, operating in the 28 and 38 GHz frequency bands. The antenna bandwidth is opt...... for access networks in the mm-wave frequency range....

Wireless security in mobile health.

Science.gov (United States)

Osunmuyiwa, Olufolabi; Ulusoy, Ali Hakan

2012-12-01

Mobile health (m-health) is an extremely broad term that embraces mobile communication in the health sector and data packaging. The four broad categories of wireless networks are wireless personal area network, wireless metropolitan area network, wireless wide area network, and wireless local area network. Wireless local area network is the most notable of the wireless networking tools obtainable in the health sector. Transfer of delicate and critical information on radio frequencies should be secure, and the right to use must be meticulous. This article covers the business opportunities in m-health, threats faced by wireless networks in hospitals, and methods of mitigating these threats.

Sensors on speaking terms: Schedule-based medium access control protocols for wireless sensor networks

NARCIS (Netherlands)

van Hoesel, L.F.W.

2007-01-01

Wireless sensor networks make the previously unobservable, observable. The basic idea behind these networks is straightforward: all wires are cut in traditional sensing systems and the sensors are equipped with batteries and radio's to virtually restore the cut wires. The resulting sensors can be

A Probabilistic Model of the LMAC Protocol for Concurrent Wireless Sensor Networks

DEFF Research Database (Denmark)

Esparza, Luz Judith R; Zeng, Kebin; Nielsen, Bo Friis

2011-01-01

We present a probabilistic model for the network setup phase of the Lightweight Medium Access Protocol (LMAC) for concurrent Wireless Sensor Networks. In the network setup phase, time slots are allocated to the individual sensors through resolution of successive collisions. The setup phase...

Optimization Modeling and Decision Support for Wireless Infrastructure Deployment in Disaster Planning and Management

DEFF Research Database (Denmark)

Bartolacci, Michael R.; Mihovska, Albena D.; Ozceylan, Dilek

2013-01-01

Natural disasters and emergencies create the need for communication between and among the affected populace and emergency responders as well as other parties such as governmental agencies and aid organizations. Such communications include the dissemination of key information such as evacuation...... orders and locations of emergency shelters. In particular, the coordination of efforts between responding organizations require additional communication solutions that typically rely heavily on wireless communications to complement fixed line infrastructure due to the ease of use and portability. While...... the deployment of temporary mobile networks and other wireless equipment following disasters has been successfully accomplished by governmental agencies and network providers following previous disasters, there appears to be little optimization effort involved with respect to maximizing key performance measures...

Efficient Bandwidth Allocation for Integrated Services in Broadband Wireless ATM Networks

DEFF Research Database (Denmark)

Liu, Hong; Dittmann, Lars; Gliese, Ulrik Bo

1999-01-01

An efficient bandwidth allocation scheme is proposed for supporting intergrated services in wireless ATM networks. These include CBR, VBR amd ABR types of traffic. The proposed scheme is based om A-PRMA for carrying ATM traffic in a dynamic TDMA type access system. It allows mobile users to adjust...

Secure Data Exchange in Environmental Health Monitoring System through Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Amang Sudarsono

2016-04-01

Full Text Available Recently, disseminating latest sensory information regarding the status of environmental health in the surroundings of human life is one of very important circumstances which must be known by everyone. These circumstances should be accessible at anytime and anywhere by everyone through any type of end-user devices, both fixed and mobile devices, i.e., Desktop PCs, Laptop PCs, and Smartphones. Wireless Sensor Network (WSN is one of the networks which deals with data sensors distribution from sensor nodes to the gateway node toward a Data Center Server. However, there is a big possibility for many adversaries to intercept and even manipulate data sensors crossing the network. Hence, a secure data sensor exchange in the system would be strongly desirable. In this research, we propose an environmental health conditions monitoring system through WSN and its implementation with considering secure data sensor exchange within the network and secure data sensor access. This work may contribute to support a part of smart cities and take in part the Internet of Thing (IoT technology. In our proposed system, we collect some environmental health information such as temperature, humidity, luminosity, noise, carbon monoxide (CO and carbon dioxide (CO2 from sensor nodes. We keep the confidentiality and integrity of transmitted data sensors propagating through IEEE802.15.4-based communication toward a gateway node. Further, the collected data sensors in the gateway are synchronized to the Data Center Server through a secure TCP/IP connection for permanently storing. At anytime and anywhere, only legitimated users who successfully pass-through an attribute-based authentication system are able to access the data sensors.

Handoff Between a Wireless Local Area Network (WLAN and a Wide Area Network (UMTS

Directory of Open Access Journals (Sweden)

J. Sánchez–García

2009-04-01

Full Text Available With the appearance of wireless data networks with variable coverage, band width and handoff strategies, in addition to the growing need of mobile nodes to freely roam among these networks, the support of an interoperable handoff strategy for hybrid wireless data networks is a requirement that needs to be addressed. The current trend in wireless data networks is to offer multimedia access to mobile users by employing the wireless local area network (WLAN standard IEEE802.11 while the user is located indoors; on the other hand, 3rd generation wireless networks (WAN are being deployed to provide coverage while the user is located outdoors. As a result, the mobile node will require a handoff mechanism to allow the user to roam between WLAN and WAN environments; up to this date several strategies have been proposed (Sattari et al., 2004 and HyoJin, 2007 in the literature, however, none of these have been standardized to date. To support this interoperability, the mobile node must be equipped with configurable wireless inetrfaces to support the handoff between the WLAN and the WAN networks. In this work a new algorithm is proposed to allow a mobile node to roam between a wireless local area network (IEEE802.11 and a WAN base station (UMTS, while employing IP mobility support. The algorithm is implemented in simulation, using the Network Simulator 2.

The Resource Mapping Algorithm of Wireless Virtualized Networks for Saving Energy in Ultradense Small Cells

Directory of Open Access Journals (Sweden)

Sai Zou

2015-01-01

Full Text Available As the current network is designed for peak loads, it results in insufficient resource utilization and energy waste. Virtualized technology makes it possible that intelligent energy perception network could be deployed and resource sharing could become an effective energy saving technology. How to make more small cells into sleeping state for energy saving in ultradense small cell system has become a research hot spot. Based on the mapping feature of virtualized network, a new wireless resource mapping algorithm for saving energy in ultradense small cells has been put forward when wireless resource amount is satisfied in every small cell. First of all, the method divides the virtual cells. Again through the alternate updating between small cell mapping and wireless resource allocation, least amount of small cells is used and other small cells turn into sleeping state on the premise of guaranteeing users’ QoS. Next, the energy consumption of the wireless access system, wireless resource utilization, and the convergence of the proposed algorithm are analyzed in theory. Finally, the simulation results demonstrate that the algorithm can effectively reduce the system energy consumption and required wireless resource amount under the condition of satisfying users’ QoS.

The radio-on-fiber-wavelength-division-multiplexed-passive-optical network (WDM-RoF-PON) for wireless and wire layout with linearly-polarized dual-wavelength fiber laser and carrier reusing

Science.gov (United States)

Ji, Wei; Chang, Jun

2013-07-01

In this paper, we design a WDM-RoF-PON based on linearly-polarized dual-wavelength fiber laser and CSRZ-DPSK, which can achieve wire-line and wireless access synchronously. With the CSRZ-DPSK modulation, the wireless access in ONU can save RF source and the frequency of radio carrier can be controlled by OLT. The dual-wavelength fiber laser is the union light source of WDM-PON with polarization multiplexing. By the RSOA and downstream light source reusing, the ONU can save omit laser source and makes the WDM-PON to be colorless. The networking has the credible transmission property, including wireless access and fiber transmission. The networking also has excellent covering range.

CCNA Wireless Study Guide

CERN Document Server

Lammle, Todd

2010-01-01

A complete guide to the CCNA Wireless exam by leading networking authority Todd Lammle. The CCNA Wireless certification is the most respected entry-level certification in this rapidly growing field. Todd Lammle is the undisputed authority on networking, and this book focuses exclusively on the skills covered in this Cisco certification exam. The CCNA Wireless Study Guide joins the popular Sybex study guide family and helps network administrators advance their careers with a highly desirable certification.: The CCNA Wireless certification is the most respected entry-level wireless certification

Wireless ad hoc networks access for aeronautical communications

OpenAIRE

Besse , Frédéric; Garcia , Fabien; Pirovano , Alain; Radzik , José

2010-01-01

International audience; There is an increasing interest in the current aeronautical context to offer new services for civil aircraft passengers. For example, airlines want to offer their customers the opportunity to access the Internet, to manage their mails, to watch video on demand, to access corporate VPNs.... All these services represent a new type of air-ground communications called APC (Aeronautical Passenger Communications) in the ATN (Aeronautical Telecommunication Network) context. I...

An Outline of Data Aggregation Security in Heterogeneous Wireless Sensor Networks.

Science.gov (United States)

Boubiche, Sabrina; Boubiche, Djallel Eddine; Bilami, Azzedine; Toral-Cruz, Homero

2016-04-12

Data aggregation processes aim to reduce the amount of exchanged data in wireless sensor networks and consequently minimize the packet overhead and optimize energy efficiency. Securing the data aggregation process is a real challenge since the aggregation nodes must access the relayed data to apply the aggregation functions. The data aggregation security problem has been widely addressed in classical homogeneous wireless sensor networks, however, most of the proposed security protocols cannot guarantee a high level of security since the sensor node resources are limited. Heterogeneous wireless sensor networks have recently emerged as a new wireless sensor network category which expands the sensor nodes' resources and capabilities. These new kinds of WSNs have opened new research opportunities where security represents a most attractive area. Indeed, robust and high security level algorithms can be used to secure the data aggregation at the heterogeneous aggregation nodes which is impossible in classical homogeneous WSNs. Contrary to the homogeneous sensor networks, the data aggregation security problem is still not sufficiently covered and the proposed data aggregation security protocols are numberless. To address this recent research area, this paper describes the data aggregation security problem in heterogeneous wireless sensor networks and surveys a few proposed security protocols. A classification and evaluation of the existing protocols is also introduced based on the adopted data aggregation security approach.

An Outline of Data Aggregation Security in Heterogeneous Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Sabrina Boubiche

2016-04-01

Full Text Available Data aggregation processes aim to reduce the amount of exchanged data in wireless sensor networks and consequently minimize the packet overhead and optimize energy efficiency. Securing the data aggregation process is a real challenge since the aggregation nodes must access the relayed data to apply the aggregation functions. The data aggregation security problem has been widely addressed in classical homogeneous wireless sensor networks, however, most of the proposed security protocols cannot guarantee a high level of security since the sensor node resources are limited. Heterogeneous wireless sensor networks have recently emerged as a new wireless sensor network category which expands the sensor nodes’ resources and capabilities. These new kinds of WSNs have opened new research opportunities where security represents a most attractive area. Indeed, robust and high security level algorithms can be used to secure the data aggregation at the heterogeneous aggregation nodes which is impossible in classical homogeneous WSNs. Contrary to the homogeneous sensor networks, the data aggregation security problem is still not sufficiently covered and the proposed data aggregation security protocols are numberless. To address this recent research area, this paper describes the data aggregation security problem in heterogeneous wireless sensor networks and surveys a few proposed security protocols. A classification and evaluation of the existing protocols is also introduced based on the adopted data aggregation security approach.

An Outline of Data Aggregation Security in Heterogeneous Wireless Sensor Networks

Science.gov (United States)

Boubiche, Sabrina; Boubiche, Djallel Eddine; Bilami, Azzedine; Toral-Cruz, Homero

2016-01-01

Data aggregation processes aim to reduce the amount of exchanged data in wireless sensor networks and consequently minimize the packet overhead and optimize energy efficiency. Securing the data aggregation process is a real challenge since the aggregation nodes must access the relayed data to apply the aggregation functions. The data aggregation security problem has been widely addressed in classical homogeneous wireless sensor networks, however, most of the proposed security protocols cannot guarantee a high level of security since the sensor node resources are limited. Heterogeneous wireless sensor networks have recently emerged as a new wireless sensor network category which expands the sensor nodes’ resources and capabilities. These new kinds of WSNs have opened new research opportunities where security represents a most attractive area. Indeed, robust and high security level algorithms can be used to secure the data aggregation at the heterogeneous aggregation nodes which is impossible in classical homogeneous WSNs. Contrary to the homogeneous sensor networks, the data aggregation security problem is still not sufficiently covered and the proposed data aggregation security protocols are numberless. To address this recent research area, this paper describes the data aggregation security problem in heterogeneous wireless sensor networks and surveys a few proposed security protocols. A classification and evaluation of the existing protocols is also introduced based on the adopted data aggregation security approach. PMID:27077866

Optimization and Verification of the TR-MAC Protocol for Wireless Sensor Networks

NARCIS (Netherlands)

Morshed, S.; Heijenk, Geert

2015-01-01

Energy-efficiency is an important requirement in the design of communication protocols for wireless sensor networks (WSN). TR-MAC is an energy-efficient medium access control (MAC) layer protocol for low power WSN that exploits transmitted-reference (TR) modulation in the physical layer. The

Wireless Transmission of Big Data: A Transmission Time Analysis over Fading Channel

KAUST Repository

Wang, Wen-Jing; Yang, Hong-Chuan; Alouini, Mohamed-Slim

2018-01-01

In this paper, we investigate the transmission time of a large amount of data over fading wireless channel with adaptive modulation and coding (AMC). Unlike traditional transmission systems, where the transmission time of a fixed amount of data is typically regarded as a constant, the transmission time with AMC becomes a random variable, as the transmission rate varies with the fading channel condition. To facilitate the design and optimization of wireless transmission schemes for big data applications, we present an analytical framework to determine statistical characterizations for the transmission time of big data with AMC. In particular, we derive the exact statistics of transmission time over block fading channels. The probability mass function (PMF) and cumulative distribution function (CDF) of transmission time are obtained for both slow and fast fading scenarios. We further extend our analysis to Markov channel, where transmission time becomes the sum of a sequence of exponentially distributed time slots. Analytical expression for the probability density function (PDF) of transmission time is derived for both fast fading and slow fading scenarios. These analytical results are essential to the optimal design and performance analysis of future wireless transmission systems for big data applications.

Wireless Transmission of Big Data: A Transmission Time Analysis over Fading Channel

KAUST Repository

Wang, Wen-Jing

2018-04-10

In this paper, we investigate the transmission time of a large amount of data over fading wireless channel with adaptive modulation and coding (AMC). Unlike traditional transmission systems, where the transmission time of a fixed amount of data is typically regarded as a constant, the transmission time with AMC becomes a random variable, as the transmission rate varies with the fading channel condition. To facilitate the design and optimization of wireless transmission schemes for big data applications, we present an analytical framework to determine statistical characterizations for the transmission time of big data with AMC. In particular, we derive the exact statistics of transmission time over block fading channels. The probability mass function (PMF) and cumulative distribution function (CDF) of transmission time are obtained for both slow and fast fading scenarios. We further extend our analysis to Markov channel, where transmission time becomes the sum of a sequence of exponentially distributed time slots. Analytical expression for the probability density function (PDF) of transmission time is derived for both fast fading and slow fading scenarios. These analytical results are essential to the optimal design and performance analysis of future wireless transmission systems for big data applications.

Spectrum access games for cognitive radio networks

CSIR Research Space (South Africa)

Masonta, MT

2010-09-01

Full Text Available received a wide acceptance in next generation and intelligent wireless communication systems. In this paper the authors make use of game theory approach to model and analyze cognitive radio networks in order to allow dynamic spectrum access in broadband...

The wireless internet explained

CERN Document Server

Rhoton, John

2001-01-01

The Wireless Internet Explained covers the full spectrum of wireless technologies from a wide range of vendors, including initiatives by Microsoft and Compaq. The Wireless Internet Explained takes a practical look at wireless technology. Rhoton explains the concepts behind the physics, and provides an overview that clarifies the convoluted set of standards heaped together under the umbrella of wireless. It then expands on these technical foundations to give a panorama of the increasingly crowded landscape of wireless product offerings. When it comes to actual implementation the book gives abundant down-to-earth advice on topics ranging from the selection and deployment of mobile devices to the extremely sensitive subject of security.Written by an expert on Internet messaging, the author of Digital Press''s successful Programmer''s Guide to Internet Mail and X.400 and SMTP: Battle of the E-mail Protocols, The Wireless Internet Explained describes and evaluates the current state of the fast-growing and crucial...

A Secure Key Establishment Protocol for ZigBee Wireless Sensor Networks

DEFF Research Database (Denmark)

Yuksel, Ender; Nielson, Hanne Riis; Nielson, Flemming

2010-01-01

ZigBee is a wireless sensor network standard that defines network and application layers on top of IEEE 802.15.4's physical and medium access control layers. In the latest version of ZigBee, enhancements are prescribed for the security sublayer but we show in this paper that problems persist...

Wireless power transfer system

Science.gov (United States)

Wu, Hunter; Sealy, Kylee; Gilchrist, Aaron

2016-02-23

A system includes a first stage of an inductive power transfer system with an LCL load resonant converter with a switching section, an LCL tuning circuit, and a primary receiver pad. The IPT system includes a second stage with a secondary receiver pad, a secondary resonant circuit, a secondary rectification circuit, and a secondary decoupling converter. The secondary receiver pad connects to the secondary resonant circuit. The secondary resonant circuit connects to the secondary rectification circuit. The secondary rectification circuit connects to the secondary decoupling converter. The second stage connects to a load. The load includes an energy storage element. The second stage and load are located on a vehicle and the first stage is located at a fixed location. The primary receiver pad wirelessly transfers power to the secondary receiver pad across a gap when the vehicle positions the secondary receiver pad with respect to the primary receiver pad.

mm-Wave Hybrid Photonic Wireless Links for Ultra-High Speed Wireless Transmissions

DEFF Research Database (Denmark)

Rommel, Simon; Vegas Olmos, Juan José; Tafur Monroy, Idelfonso

Hybrid photonic-wireless transmission schemes in the mm-wave frequency range are promising candidates to enable the multi-gigabit per second data communications required from wireless and mobile networks of the 5th and future generations. Large FCC spectrum allocations for wireless transmission...

Collaborative Indoor Access Point Localization Using Autonomous Mobile Robot Swarm.

Science.gov (United States)

Awad, Fahed; Naserllah, Muhammad; Omar, Ammar; Abu-Hantash, Alaa; Al-Taj, Abrar

2018-01-31

Localization of access points has become an important research problem due to the wide range of applications it addresses such as dismantling critical security threats caused by rogue access points or optimizing wireless coverage of access points within a service area. Existing proposed solutions have mostly relied on theoretical hypotheses or computer simulation to demonstrate the efficiency of their methods. The techniques that rely on estimating the distance using samples of the received signal strength usually assume prior knowledge of the signal propagation characteristics of the indoor environment in hand and tend to take a relatively large number of uniformly distributed random samples. This paper presents an efficient and practical collaborative approach to detect the location of an access point in an indoor environment without any prior knowledge of the environment. The proposed approach comprises a swarm of wirelessly connected mobile robots that collaboratively and autonomously collect a relatively small number of non-uniformly distributed random samples of the access point's received signal strength. These samples are used to efficiently and accurately estimate the location of the access point. The experimental testing verified that the proposed approach can identify the location of the access point in an accurate and efficient manner.

Collaborative Indoor Access Point Localization Using Autonomous Mobile Robot Swarm

Directory of Open Access Journals (Sweden)

Fahed Awad

2018-01-01

Full Text Available Localization of access points has become an important research problem due to the wide range of applications it addresses such as dismantling critical security threats caused by rogue access points or optimizing wireless coverage of access points within a service area. Existing proposed solutions have mostly relied on theoretical hypotheses or computer simulation to demonstrate the efficiency of their methods. The techniques that rely on estimating the distance using samples of the received signal strength usually assume prior knowledge of the signal propagation characteristics of the indoor environment in hand and tend to take a relatively large number of uniformly distributed random samples. This paper presents an efficient and practical collaborative approach to detect the location of an access point in an indoor environment without any prior knowledge of the environment. The proposed approach comprises a swarm of wirelessly connected mobile robots that collaboratively and autonomously collect a relatively small number of non-uniformly distributed random samples of the access point’s received signal strength. These samples are used to efficiently and accurately estimate the location of the access point. The experimental testing verified that the proposed approach can identify the location of the access point in an accurate and efficient manner.

The television white space opportunity in Southern Africa: from field measurements to quantifying white spaces

CSIR Research Space (South Africa)

Lysko, AA

2015-01-01

Full Text Available The lack of sufficient fixed-line communication infrastructure in African rural areas has resulted in wireless communication being the only cost effective alternative solution for broadband connectivity. However, access to valuable spectrum...

Scalable Video Streaming Relay for Smart Mobile Devices in Wireless Networks.

Science.gov (United States)

Kwon, Dongwoo; Je, Huigwang; Kim, Hyeonwoo; Ju, Hongtaek; An, Donghyeok

2016-01-01

Recently, smart mobile devices and wireless communication technologies such as WiFi, third generation (3G), and long-term evolution (LTE) have been rapidly deployed. Many smart mobile device users can access the Internet wirelessly, which has increased mobile traffic. In 2014, more than half of the mobile traffic around the world was devoted to satisfying the increased demand for the video streaming. In this paper, we propose a scalable video streaming relay scheme. Because many collisions degrade the scalability of video streaming, we first separate networks to prevent excessive contention between devices. In addition, the member device controls the video download rate in order to adapt to video playback. If the data are sufficiently buffered, the member device stops the download. If not, it requests additional video data. We implemented apps to evaluate the proposed scheme and conducted experiments with smart mobile devices. The results showed that our scheme improves the scalability of video streaming in a wireless local area network (WLAN).

Scalable Video Streaming Relay for Smart Mobile Devices in Wireless Networks

Science.gov (United States)

Kwon, Dongwoo; Je, Huigwang; Kim, Hyeonwoo; Ju, Hongtaek; An, Donghyeok

2016-01-01

Recently, smart mobile devices and wireless communication technologies such as WiFi, third generation (3G), and long-term evolution (LTE) have been rapidly deployed. Many smart mobile device users can access the Internet wirelessly, which has increased mobile traffic. In 2014, more than half of the mobile traffic around the world was devoted to satisfying the increased demand for the video streaming. In this paper, we propose a scalable video streaming relay scheme. Because many collisions degrade the scalability of video streaming, we first separate networks to prevent excessive contention between devices. In addition, the member device controls the video download rate in order to adapt to video playback. If the data are sufficiently buffered, the member device stops the download. If not, it requests additional video data. We implemented apps to evaluate the proposed scheme and conducted experiments with smart mobile devices. The results showed that our scheme improves the scalability of video streaming in a wireless local area network (WLAN). PMID:27907113

Over-the-horizon, connected home/office (OCHO): situation management of environmental, medical, and security conditions at remote premises via broadband wireless access

Science.gov (United States)

Hortos, William S.

2010-04-01

Broadband wireless access standards, together with advances in the development of commercial sensing and actuator devices, enable the feasibility of a consumer service for a multi-sensor system that monitors the conditions within a residence or office: the environment/infrastructure, patient-occupant health, and physical security. The proposed service is a broadband reimplementation and combination of existing services to allow on-demand reports on and management of the conditions by remote subscribers. The flow of on-demand reports to subscribers and to specialists contracted to mitigate out-of-tolerance conditions is the foreground process. Service subscribers for an over-the-horizon connected home/office (OCHO) monitoring system are the occupant of the premises and agencies, contracted by the service provider, to mitigate or resolve any observed out-of-tolerance condition(s) at the premises. Collectively, these parties are the foreground users of the OCHO system; the implemented wireless standards allow the foreground users to be mobile as they request situation reports on demand from the subsystems on remote conditions that comprise OCHO via wireless devices. An OCHO subscriber, i.e., a foreground user, may select the level of detail found in on-demand reports, i.e., the amount of information displayed in the report of monitored conditions at the premises. This is one context of system operations. While foreground reports are sent only periodically to subscribers, the information generated by the monitored conditions at the premises is continuous and is transferred to a background configuration of servers on which databases reside. These databases are each used, generally, in non-real time, for the assessment and management of situations defined by attributes like those being monitored in the foreground by OCHO. This is the second context of system operations. Context awareness and management of conditions at the premises by a second group of analysts and

Wireless Phone Use and Risk of Adult Glioma: Evidence from a Meta-Analysis.

Science.gov (United States)

Wang, Peng; Hou, Chongxian; Li, Yanwen; Zhou, Dong

2018-04-28

Wireless phone use has been increasing rapidly and is associated with the risk of glioma. Many studies have been conducted on this association without reaching agreement. The aim of this meta-analysis was to determine the possible association between wireless phone use and risk of adult glioma. Eligible studies were identified by searching PubMed and Embase up to July 2017. Random-effects or fixed-effects model was used to combine the results depending on the heterogeneity of the analysis. Publication bias was evaluated using Begg's funnel plot and Egger's regression asymmetry test. Subgroup analysis was performed to evaluate possible influence of these variables. Ten studies on the association of wireless phone use and risk of glioma were included. The combined odds ratio of adult gliomas associated with ever use of wireless phones was 1.03 (95% confidence interval [CI], 0.92-1.16) with high heterogeneity (I 2  = 54.2%, P = 0.013). In subgroup analyses, no significant association was found between tumor location in the temporal lobe and adult glioma risk, with odds ratios of 1.26 (95% CI, 0.87-1.84), 0.93 (95% CI, 0.69-1.24), and 1.61 (95% CI, 0.78-3.33). A significant association with risk of glioma was found in long-term users (≥10 years) with odds ratio of 1.33 (95% CI, 1.05-1.67). Ever use of wireless phones was not significantly associated with risk of adult glioma, but there could be increased risk in long-term users. Copyright © 2018 Elsevier Inc. All rights reserved.

GSM module for wireless radiation monitoring system via SMS

Science.gov (United States)

Rahman, Nur Aira Abd; Hisyam Ibrahim, Noor; Lombigit, Lojius; Azman, Azraf; Jaafar, Zainudin; Arymaswati Abdullah, Nor; Hadzir Patai Mohamad, Glam

2018-01-01

A customised Global System for Mobile communication (GSM) module is designed for wireless radiation monitoring through Short Messaging Service (SMS). This module is able to receive serial data from radiation monitoring devices such as survey meter or area monitor and transmit the data as text SMS to a host server. It provides two-way communication for data transmission, status query, and configuration setup. The module hardware consists of GSM module, voltage level shifter, SIM circuit and Atmega328P microcontroller. Microcontroller provides control for sending, receiving and AT command processing to GSM module. The firmware is responsible to handle task related to communication between device and host server. It process all incoming SMS, extract, and store new configuration from Host, transmits alert/notification SMS when the radiation data reach/exceed threshold value, and transmits SMS data at every fixed interval according to configuration. Integration of this module with radiation survey/monitoring device will create mobile and wireless radiation monitoring system with prompt emergency alert at high-level radiation.

Design of Cyberwar Laboratory Exercises to Implement Common Security Attacks against IEEE 802.11 Wireless Networks

Directory of Open Access Journals (Sweden)

Mina Malekzadeh

2010-01-01

Full Text Available In wireless network communications, radio waves travel through free space; hence, the information reaches any receiving point with appropriate radio receivers. This aspect makes the wireless networks vulnerable to various types of attacks. A true understanding of these attacks provides better ability to defend the network against the attacks, thus eliminating potential threats from the wireless systems. This work presents a series of cyberwar laboratory exercises that are designed for IEEE 802.11 wireless networks security courses. The exercises expose different aspects of violations in security such as confidentiality, privacy, availability, and integrity. The types of attacks include traffic analysis, rogue access point, MAC filtering, replay, man-in-the-middle, and denial of service attacks. For each exercise, the materials are presented as open-source tools along with descriptions of the respective methods, procedures, and penetration techniques.

Design and Implementation of an IoT Access Point for Smart Home

Directory of Open Access Journals (Sweden)

Chih-Yung Chang

2015-12-01

Full Text Available Network communication and micro-electro-mechanical embedded technologies have attracted much attention in recent years. Through these technologies, the capabilities of sensing, identification, and communication can be embedded in various smart devices. These smart devices can automatically connect to the Internet and form an intelligent network called Internet of Things (IoT. However, these devices are embedded with different wireless communication interfaces such as Wi-Fi and ZigBee. This paper presents the design and implementation of an IoT access point that supports functionalities of coordination of various wireless transmission protocols. Based on the existing Wi-Fi access point, we have embedded a ZigBee module and implemented ZigBee and UPnP protocols into the designed IoT access point, which supports ZigBee communication capabilities over the Internet.

Dense Clustered Multi-Channel Wireless Sensor Cloud

Directory of Open Access Journals (Sweden)

Sivaramakrishnan Sivakumar

2015-08-01

Full Text Available Dense Wireless Sensor Network Clouds have an inherent issue of latency and packet drops with regards to data collection. Though there is extensive literature that tries to address these issues through either scheduling, channel contention or a combination of the two, the problem still largely exists. In this paper, a Clustered Multi-Channel Scheduling Protocol (CMSP is designed that creates a Voronoi partition of a dense network. Each partition is assigned a channel, and a scheduling scheme is adopted to collect data within the Voronoi partitions. This scheme collects data from the partitions concurrently and then passes it to the base station. CMSP is compared using simulation with other multi-channel protocols like Tree-based Multi-Channel, Multi-Channel MAC and Multi-frequency Media Access Control for wireless sensor networks. Results indicate CMSP has higher throughput and data delivery ratio at a lower power consumption due to network partitioning and hierarchical scheduling that minimizes load on the network.

Wireless optical network for a home network

Science.gov (United States)

Bouchet, Olivier; Porcon, Pascal; Walewski, Joachim W.; Nerreter, Stefan; Langer, Klaus-Dieter; Fernández, Luz; Vucic, Jelena; Kamalakis, Thomas; Ntogari, Georgia; Neokosmidis, Ioannis; Gueutier, Eric

2010-08-01

During the European collaborative project OMEGA, two optical-wireless prototypes have been developed. The first prototype operates in the near-infrared spectral region and features Giga Ethernet connectivity, a simple transceiver architecture due to the use of on-off keying, a multi-sector transceiver, and an ultra-fast switch for sector-to-sector hand over. This full-duplex system, composed by one base station and one module, transmits data on three meters. The second prototype is a visible-light-communications system based on DMT signal processing and an adapted MAC sublayer. Data rates around to 100 Mb/s at the physical layer are achieved. This broadcast system, composed also by one base station and one module, transmits data up to two meters. In this paper we present the adapted optical wireless media-access-control sublayer protocol for visible-light communications. This protocol accommodates link adaptation from 128 Mb/s to 1024 Mb/s with multi-sector coverage, and half-duplex or full-duplex transmission.

Fast collision resolution for real time services in SDMA based wireless ATM networks

DEFF Research Database (Denmark)

Vornefeld, U.; Schieimer, D.; Walke, B.

1999-01-01

protocol, the influence of SDMA on a contention based access protocol is investigated under collision resolution schemes derived from classical splitting algorithms. Although this work is embedded in the framework of wireless ATM and HIPERLAN/2 systems, the ideas are generally applicable....

Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture

Science.gov (United States)

Steele, Kerry D [Kennewick, WA; Anderson, Gordon A [Benton City, WA; Gilbert, Ronald W [Morgan Hill, CA

2011-02-01

Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture are described. In one aspect, a communications device identification method includes providing identification information regarding a group of wireless identification devices within a wireless communications range of a reader, using the provided identification information, selecting one of a plurality of different search procedures for identifying unidentified ones of the wireless identification devices within the wireless communications range, and identifying at least some of the unidentified ones of the wireless identification devices using the selected one of the search procedures.

Application priority framework for fixed mobile converged communication networks

OpenAIRE

Chaudhry, Saqib Rasool

2011-01-01

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. The current prospects in wired and wireless access networks, it is becoming increasingly important to address potential convergence in order to offer integrated broadband services. These systems will need to offer higher data transmission capacities and long battery life, which is the catalyst for an everincreasing variety of air interface technologies targeting local area to wide area connec...

Wireless adiabatic power transfer

International Nuclear Information System (INIS)

Rangelov, A.A.; Suchowski, H.; Silberberg, Y.; Vitanov, N.V.

2011-01-01

Research highlights: → Efficient and robust mid-range wireless energy transfer between two coils. → The adiabatic energy transfer is analogous to adiabatic passage in quantum optics. → Wireless energy transfer is insensitive to any resonant constraints. → Wireless energy transfer is insensitive to noise in the neighborhood of the coils. - Abstract: We propose a technique for efficient mid-range wireless power transfer between two coils, by adapting the process of adiabatic passage for a coherently driven two-state quantum system to the realm of wireless energy transfer. The proposed technique is shown to be robust to noise, resonant constraints, and other interferences that exist in the neighborhood of the coils.

Wireless communication technology NFC

OpenAIRE

MÁROVÁ, Kateřina

2014-01-01

Aim of this bachelor thesis is to handle the issue of new wireless communication technology NFC (Near Field Communication) including a comparison of advantages and disadvantages of NFC with other wireless technologies (Bluetooth, Wi-Fi, etc.). NFC is a technology for wireless communications between different electronic devices, one of which is typically a mobile phone. Near Field Communication allows wireless communication at very short distance by approaching or enclosing two devices and can...

75 FR 8400 - In the Matter of Certain Wireless Communications System Server Software, Wireless Handheld...

Science.gov (United States)

2010-02-24

... Communications System Server Software, Wireless Handheld Devices and Battery Packs; Notice of Investigation... within the United States after importation of certain wireless communications system server software... certain wireless communications system server software, wireless handheld devices or battery packs that...