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Torrance, CA, United States

Martinez F.J.,University of Zaragoza | Toh C.K.,Alico Systems Inc | Toh C.K.,National Cheng Kung University | Cano J.-C.,Polytechnic University of Valencia | And 2 more authors.
Wireless Personal Communications

In this paper, we present a statistical analysis based on the 2k factorial methodology to determine the representative factors affecting traffic safety applications in Vehicular ad hoc networks (VANETs). Our purpose is to determine what are the key factors affecting Warning Message Dissemination (WMD) in order to concentrate on such parameters, thus reducing the amount of required simulation time when evaluating VANETs. Simulation results show that the key factors affecting warning messages delivery are: (i) the transmission range, (ii) the radio propagation model used, and (iii) the density of vehicles. Based on this statistical analysis, we evaluate a compound key factor: neighbor density. This factor combines the above-mentioned factors into a single entity, reducing the number of factors that must be taken into account for VANET researchers to evaluate the benefits of their proposals. © 2011 Springer Science+Business Media, LLC. Source

Mirkamali A.,Ecole Polytechnique de Montreal | Mirkamali A.,Alico Systems Inc | Deban R.,Ecole Polytechnique de Montreal | Siaka F.,Ecole Polytechnique de Montreal | Laurin J.-J.,Ecole Polytechnique de Montreal
IET Microwaves, Antennas and Propagation

A novel feed system for circular arrays enabling beam steering over 360° in the azimuth plane with a stable scanned beam is proposed. It consists of rotating and fixed parts. The rotating part is a two-dimensional offset fed parabolic reflector which is inside a circular parallel plate waveguide. The power coming from the rotating part is coupled with the elements of the circular array through a fixed coupling structure. The rotating part is light and its moment of inertia is significantly less than the conventional rotating antenna systems for beam scanning. Therefore, the beam can be steered much faster than the current rotating antenna systems. The details of the structure including the rotating and the fixed parts are presented and a design procedure for the fixed coupling section is suggested. The performance of the feed system is investigated by simulations and measurements. It is shown that the simulations and experimental results are in good agreement. © The Institution of Engineering and Technology. Source

Fulton C.J.,University of Oklahoma | Mirkamali A.,Alico Systems Inc
IEEE Antennas and Propagation Magazine

A computer-aided technique is proposed to obtain the embedded characteristics of the elements in a cylindrical phased array using a unitcell approach in Ansys High Frequency Structure Simulator (HFSS). The proposed technique is general and can be used with other commercially available electromagnetic (EM) products that support periodic boundary conditions. Therefore, it can be widely adopted by engineers and researchers to analyze arbitrary element structures in cylindrical phased arrays. The implementation of the technique is discussed in detail, and the related formulation is presented. The method is verified by comparing its results with published literature as well as results obtained through full-wave analysis of a ring of microstrip patch antennas in HFSS. © 1990-2011 IEEE. Source

Cano J.,Polytechnic University of Valencia | Cano J.-C.,Polytechnic University of Valencia | Toh C.K.,Alico Systems Inc | Calafate C.T.,Polytechnic University of Valencia | Manzoni P.,Polytechnic University of Valencia
IEEE Communications Magazine

Mobile ad hoc networks are highly dynamic networks that offer multihop communications in the presence of changing topologies without the need for any fixed infrastructure support. These networks can be useful in a wide variety of scenarios, but setting them up and deploying services on them is a difficult task, even for experienced users. In this article we present EasyMANET 's an extensible platform the main objective of which is to encourage the widespread adoption and use of MANETs by non-expert users. To achieve this objective, EasyMANET provides two essential elements: an address autoconfiguration system and a name resolution service known as Visual DNS. The autoconfiguration system allows users to join an 802.11-based MANET by establishing the parameters of their terminal interfaces quickly and transparently. Thereafter, Visual DNS offers a graphical view of MANET participants and gives users the possibility to access the services made available by other users. Examples are communication services (text-based chat, VoIP, videoconference), file sharing, and localization services. We performed several laboratory experiments, and evaluated the performance of EasyMANET based on address autoconfiguration time and Visual DNS performance. Results show that EasyMANET can be established within seconds, and EasyMANET applications are easy to use. In fact, over 360 students have tried using Easy- MANET without problems. © 2006 IEEE. Source

Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 119.51K | Year: 2008

Currently there is no affordable military band on-the-move non-line-of-sight (NLOS) or beyond-line-of-sight (BLOS) communications capability available for land vehicles, helicopters, boats or small UAVs. The current state-of-the-art in Satellite-On-the-Move (SOTM) terminals for Blue Force Tracking (BFT) application is the unit deployed for OIF/OEF which provides 2.4 Kbps utilizing a commercial L-band satellite. The key goals of this project is to develop a low cost, military band, high data rate (> 16 Kbps) on-the-move (OTM), small footprint (< 1 cubic foot) satellite terminal which supports Blue Force Tracking (BFT), situation awareness (SA), and C2 missions. We have investigated the DoD satellite offerings and believe that the X-band Wideband Gap Filler Satellite (WGS) provides the optimum capability to support small aperture on-the-move terminals. Our proposed design will support WGS X-band. In the interim these terminals will also support XTAR a commercial X-band service provider with operational capability available today. Alico Systems proposed approach is based on utilizing low cost beam steering antenna technology with no moving parts. An innovative approach is proposed for tracking the satellite with low cost components. Our design supports >32 Kbps forward and >8 Kbps reverse data rate on-the-move with a

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