1,234 research outputs found
Medium Access Control for Wireless Sensor Networks based on Impulse Radio Ultra Wideband
This paper describes a detailed performance evaluation of distributed Medium
Access Control (MAC) protocols for Wireless Sensor Networks based on Impulse
Radio Ultra Wideband (IR-UWB) Physical layer (PHY). Two main classes of Medium
Access Control protocol have been considered: Slotted and UnSlotted with
reliability. The reliability is based on Automatic Repeat ReQuest (ARQ). The
performance evaluation is performed using a complete Wireless Sensor Networks
(WSN) simulator built on the Global Mobile Information System Simulator
(GloMoSim). The optimal operating parameters are first discussed for IR-UWB in
terms of slot size, retransmission delay and the number of retransmission, then
a comparison between IR-UWB and other transmission techniques in terms of
reliability latency and power efficiency
Simulation Platform for Wireless Sensor Networks Based on Impulse Radio Ultra Wide Band
Impulse Radio Ultra Wide Band (IR-UWB) is a promising technology to address
Wireless Sensor Network (WSN) constraints. However, existing network simulation
tools do not provide a complete WSN simulation architecture, with the IR-UWB
specificities at the PHYsical (PHY) and the Medium Access Control (MAC) layers.
In this paper, we propose a WSN simulation architecture based on the IR-UWB
technique. At the PHY layer, we take into account the pulse collision by
dealing with the pulse propagation delay. We also modelled MAC protocols
specific to IRUWB, for WSN applications. To completely fit the WSN simulation
requirements, we propose a generic and reusable sensor and sensing channel
model. Most of the WSN application performances can be evaluated thanks to the
proposed simulation architecture. The proposed models are implemented on a
scalable and well known network simulator: Global Mobile Information System
Simulator (GloMoSim). However, they can be reused for all other packet based
simulation platforms
Performance Evaluation of Impluse Radio Ultra Wide Band Wireless Sensor Networks
This paper presents a performance evaluation of Wireless Sensor Networks
(WSN) based on Impulse Radio Ultra Wideband (IR-UWB) over a new simulation
platform developed for this purpose. The simulation platform is built on an
existing network simulator: Global Mobile Information System Simulator
(GloMoSim). It mainly focuses on the accurately modeling of IR-UWB PHYsical
(PHY) and Medium Access Control (MAC) layer. Pulse collision is modeled
according to the used time hopping sequence (THS) and the pulse propagation
delay in order to increase the simulation fidelity. It also includes a
detection and identification application based on a new sensing channel and new
sensor device models. The proposed architecture is generic so it can be reused
for any simulation platform. The performance evaluation is based on one of the
typical WSN applications: local area protection, where sensor nodes are densely
scattered in an access regulated area in order to detect, identify and report
non authorized accesses to a base station for analysis. Two networks topologies
using different protocol stacks are investigated. Their performance evaluation
is presented in terms of reliability and latency
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 2Ă—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.Â
Wireless Alliance for Testing Experiment and Research (WALTER) Experts Workshop
The purpose of the publication is to describe the WALTER experts workshop and related results and findings.
The workshop was conducted in Ispra, Varese, Italy from the 2nd to the 3rd of July 2008 at the European Commission JRC facilities.
The workshop was organized as part of the FP7 WALTER project, which has the objective of define a networked test bed laboratory to evaluate UltraWideBand (UWB) technology and equipment.
The purpose of WALTER workshop was to present and discuss the current regulatory, standardization and research status of UltraWideBand (UWB) technology with special focus on the definition of requirements, methodologies and tools for UWB measurements and testing.
The WALTER workshop had the following main objectives:
- Identify the main regulatory and standardization challenges for the adoption of UWB in Europe and the world. Support the identification and resolution of conflicting requirements.
- Identify the main challenges in the UWB testing and measurements. Describe how the current industrial and research activity could support the resolution of these challenges.
- Discuss the future developments like UWB at 60 GHz and innovative interference and mitigation techniques including Detect And Avoid (DAA).
A number of international experts in the UltraWideBand field have been invited to participate to this workshop, to encourage bi-directional communication: in one direction to disseminate the information on WALTER project and its activities, in the other direction to collect the input and feedback on the regulatory and standardization work, industrial activity and research studies.JRC.G.6-Sensors, radar technologies and cybersecurit
- …