1,351 research outputs found
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
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
BCB Based Packaging for Low Actuation Voltage RF MEMS Devices
This paper outlines the issues related to RF MEMS packaging and low actuation
voltage. An original approach is presented concerning the modeling of
capacitive contacts using multiphysics simulation and advanced
characterization. A similar approach is used concerning packaging development
where multi-physics simulations are used to optimize the process. A devoted
package architecture is proposed featuring very low loss at microwave range
Millimeter wave carbon nanotube gas sensor
This Letter reports experimental observations regarding the significant changes in the transmission modulus and phase of the propagating microwave signals up to 110 GHz in a micromachined coplanar waveguide supported on a dielectric membrane with a thickness of 1.4 m filled with a mixture of carbon nanotubes when exposed to nitrogen gas. These large shifts of amplitude and phase of microwave signals due to gas absorption represent the experimental basis on which a miniature wireless gas sensor could be implemented
- …