A Review of UWB MAC Protocols

In this paper, we review several ultra-wideband (UWB) medium access control (MAC) protocols that have been proposed to date. This review then considers the possibility of developing an optimal MAC layer for high data rate UWB transmission systems that transmit very little power especially in application to mobile devices. MAC in UWB wireless networks is necessary to coordinate channel access among competing devices. Unique UWB characteristics offer great challenges and opportunities in effective UWB MAC design. We first present the background of UWB and the concept of MAC protocols for UWB. Secondly, we summarize four UWB MAC protocols that have been proposed by other researchers and finally, a conclusion with a view to the planned future work. The main contribution of this paper is that it presents a summarised version of several MAC protocols applicable to UWB systems. This will hopefully initiate further research and developments in UWB MAC protocol design

Finding the Optimal MAC Protocol for Low-Power High Data Rate Ultra-Wideband (UWB) Networks

In this paper, we explore the possibility of designing an optimal medium access control (MAC) layer for high data rate ultra-wideband (UWB) transmission systems that transmit very little power especially in mobile devices. MAC in UWB wireless networks is necessary to coordinate channel access among competing devices. The unique UWB characteristics offer great challenges and opportunities in effective UWB MAC design. We first study the background of UWB and available MAC protocols that have been used in UWB. Secondly, we analyse the power consumption for UWB in mobile devices based on competing short-range wireless technologies such as Bluetooth and Wi-Fi as references. Finally we present the key issue that will be considered in the design of an optimal MAC layer that will fully exploit UWB potential as a low-power, high data rate, short range wireless transmission system

Ultra wideband: applications, technology and future perspectives

Ultra Wide Band (UWB) wireless communications offers a radically different approach to wireless communication compared to conventional narrow band systems. Global interest in the technology is huge. This paper reports on the state of the art of UWB wireless technology and highlights key application areas, technological challenges, higher layer protocol issues, spectrum operating zones and future drivers. The majority of the discussion focuses on the state of the art of UWB technology as it is today and in the near future

An efficient ultra-wideband digital transceiver for wireless applications on the field-programmable gate array platform

The ultra-wideband (UWB) technology is a promising short-range communication technology for most wireless applications. The UWB works at higher frequencies and is affected by interferences with the same frequency standards. This manuscript has designed an efficient and low-cost implementation of IEEE 802.15.4a-based UWB-digital transceiver (DTR). The design module contains UWB transmitter (TX), channel, and UWB-receiver (RX) units. Convolutional encoding and modulation units like burst position modulation and binary phase-shift keying modulation are used to construct the UWB-TX. The synchronization and Viterbi decoder units are used to recover the original data bits and are affected by noise in UWB-RX. The UWB-DTR is synthesized using Xilinx ISE® environment with Verilog hardware description language (HDL) and implemented on Artix-7 field-programmable gate array (FPGA). The UWB-DTR utilizes less than 2% (slices and look-up table/LUTs), operates at 268 MHz, and consumes 91 mW of total power on FPGA. The transceiver achieves a 6.86 Mbps data rate, which meets the IEEE 802.15.4a standard. The UWB-DTR module obtains the bit error rate (BER) of 2×10-4 by transmitting 105 data bits. The UWB-DTR module is compared with similar physical layer (PHY) transceivers with improvements in chip area (slices), power, data rate, and BER. 

An Overview on Wireless Sensor Networks Technology and Evolution

Wireless sensor networks (WSNs) enable new applications and require non-conventional paradigms for protocol design due to several constraints. Owing to the requirement for low device complexity together with low energy consumption (i.e., long network lifetime), a proper balance between communication and signal/data processing capabilities must be found. This motivates a huge effort in research activities, standardization process, and industrial investments on this field since the last decade. This survey paper aims at reporting an overview of WSNs technologies, main applications and standards, features in WSNs design, and evolutions. In particular, some peculiar applications, such as those based on environmental monitoring, are discussed and design strategies highlighted; a case study based on a real implementation is also reported. Trends and possible evolutions are traced. Emphasis is given to the IEEE 802.15.4 technology, which enables many applications of WSNs. Some example of performance characteristics of 802.15.4-based networks are shown and discussed as a function of the size of the WSN and the data type to be exchanged among nodes

A low Complexity Wireless Gigabit Ethernet IFoF 60 GHz H/W Platform and Issues

6 pagesInternational audienceThis paper proposes a complete IFoF system architecture derived from simplified IEEE802.15.3c PHY layer proposal to successfully ensure near 1 Gbps on the air interface. The system architecture utilizes low complexity baseband processing modules. The byte/frame synchronization technique is designed to provide a high value of preamble detection probability and a very small value of the false detection probability. Conventional Reed-Solomon RS (255, 239) coding is used for Channel Forward Error Correction (FEC). Good communication link quality and Bit Error Rate (BER) results at 875 Mbps are achieved with directional antennas

Modélisation et simulation de réseaux locaux et personnels sans fil : intégration des couches PHY et MAC

Dans ce travail nous nous intéressons à la modélisation des couches MAC et PHY dans le cadre des réseaux sans fil à faible, portée. Il présente les techniques de modélisation utilisées pour l'intégration des couches MAC-PHYs (Medium Access Control and Physical layer) de type IR-UWB (Impulse Radio Ultra Wideband) d'une part, et des nouvelles techniques de transmission à 60GHz incluant le beamforming d'autre part, dans le simulateur GloMoSim/QualNet. La modélisation de IR-UWB est basée sur la prise en compte directe des collisions d'impulsions et de l'interférence multi-utilisateur au niveau de la couche PHY par l'introduction du concept de séquences de réception et la notion d'orthogonalité en réception. L'architecture de modélisation proposée est basée sur l'utilisation d'une matrice d'interférence, elle a été développée en deux étapes : une première modélisation basée sur des trains d'impulsions uniformément espacées et une deuxième modélisation plus complète prenant en compte l'utilisation des séquences de sauts aléatoires également appelés séquences de time hopping. L'évaluation de performances de cette partie est basée sur une application typique des réseaux de capteurs dans le cadre d'une application de détection d'intrusion sur une surface protégée. La modélisation à 60 GHz à pour but la prise en compte des nouvelles techniques d'amélioration du débit, notamment l'agrégation et le beamforming. La prise en compte du beamforming est basée sur la définition, des diagrammes de rayonnement des antennes ainsi que de l'interface MAC-PHY/Antenne. La modélisation des deux protocoles de beamforming définis dans le standard 802.15.3c est également effectuée. L'évaluation de performances de cette partie est basée sur un système de distribution de contenu multimédia.In this work, we focus on physical and medium access control layer modeling and simulation for short range wireless communication. In particular, the modeling of the Impulse Radio Ultra Wide Band technique for wireless sensor networks and the high data rate communication modeling which uses millimeter wave and beamforming. The first part deals with the modeling of Impulse Radio Ultra Wide Band. The proposed model takes into account the pulse collision induced by multiple concurrent transmissions at the physical layer which is also called multi user interference. This aspect is accurately introduced thanks to the concept of reception time hopping sequences of concurrent reception and their orthogonality. The simulation architecture is built using two models: the first model is based on a uniformly distributed pulse train and the second model, more complete, takes into account variable time hopping sequences. The performance evaluation of this part is based on a typical wireless sensor networks application, in which sensor nodes are scattered on a particular area to detect and report intrusion events to a base station. The second part deals with the modeling of high data rate communication using millimeter wave. The targeted goal of millimeter wave transmission is to increase the data rate using some novel techniques: beamforming and data aggregation. Beamforming is modeled on the so-called codebook beamforming defined as the new beamforming technique for high data rate wireless communication standards. A methodology is developed to take into account the radiation pattern defined by the codebook indexes. For each index the gain of the directional antenna is computed for each direction. This is used in the simulation model physical layer to determine the directional antenna gain in a particular direction during the propagation stage. The defined protocols for sector level and beam level training defined in the 802.15.3c draft are also modeled. The performance evaluation of this part is based on a multimedia distribution system

Analysis of the IEEE 802.15.4a ultra wideband physical layer through wireless sensor network simulations in OMNET++

Wireless Sensor Networks are the main representative of pervasive computing in large-scale physical environments. These networks consist of a large number of small, wireless devices embedded in the physical world to be used for surveillance, environmental monitoring or other data capture, processing and transfer applications. Ultra wideband has emerged as one of the newest and most promising concepts for wireless technology. Considering all its advantages it seems a likely communication technology candidate for future wireless sensor networks. This paper considers the viability of ultra wideband technology in wireless sensor networks by employing an IEEE 802.15.4a low-rate ultra wideband physical layer model in the OMNET++ simulation environment. An elaborate investigation into the inner workings of the IEEE 802.15.4a UWB physical layer is performed. Simulation experiments are used to provide a detailed analysis of the performance of the IEEE 802.15.4a UWB physical layer over several communication distances. A proposal for a cognitive, adaptive communication approach to optimize for speed and distance is also presented. AFRIKAANS : Draadlose Sensor Netwerke is die hoof verteenwoordiger vir deurdringende rekenarisering in groot skaal fisiese omgewings. Hierdie tipe netwerke bestaan uit ’n groot aantal klein, draadlose apparate wat in die fisiese wêreld ingesluit word vir die doel van bewaking, omgewings monitering en vele ander data opvang, verwerk en oordrag applikasies. Ultra wyeband het opgestaan as een van die nuutste en mees belowend konsepte vir draadlose kommunikasie tegnologie. As al die voordele van dié kommunikasie tegnologie in ag geneem word, blyk dit om ’n baie goeie kandidaat te wees vir gebruik in toekomstige draadlose sensor netwerke. Hierdie verhandeling oorweeg die vatbaarheid van die gebruik van die ultra wyeband tegnologie in draadlose sensor netwerke deur ’n IEEE 802.15.4a lae-tempo ultra wyeband fisiese laag model in die OMNET++ simulasie omgewing toe te pas. ’n Breedvoerige ondersoek word geloots om die fyn binneste werking van die IEEE 802.15.4a UWB fisiese laag te verstaan. Simulasie eksperimente word gebruik om ’n meer gedetaileerde analiese omtrent die werkverrigting van die IEEE 802.15.4a UWB fisiese laag te verkry oor verskillende kommunikasie afstande. ’n Voorstel vir ’n omgewings bewuste, aanpasbare kommunikasie tegniek word bespreek met die doel om die spoed en afstand van kommunikasie te optimiseer.Dissertation (MEng)--University of Pretoria, 2011.Electrical, Electronic and Computer Engineeringunrestricte