New Paper Reveals the Importance of Vehicles as Obstacles in Vehicular Networks

 Rui Meireles and Mate Boban

Rui Meireles and Mate Boban, dual degree Ph.D. students in Computer Science (CS) and Electrical and Computer Engineering (ECE), respectively, will present their paper "Experimental Study on the Impact of Obstructions in Vehicular Ad Hoc Networks" at the 2010 IEEE Vehicular Networking Conference. 

This international conference, which will be held in December 13-15, 2010, in Jersey City, New Jersey, seeks to bring together researchers, professionals, and practitioners to present and discuss recent developments and challenges in vehicular networking technologies, and their applications.

Meireles explains that "channel models for vehicular networks typically disregard the effect of vehicles as physical obstructions for the wireless signal". For this reason, in this paper, the authors aim to clarify the vali-dity of this simplification by quantifying the impact of obstructions through a series of wireless experiments.

In the abstract of the paper, the authors explain: "Using two cars equipped with Dedicated Short Range Communications (DSRC) hardware designed for vehicular use, we perform experimental measurements in order to collect received signal power and packet delivery ratio information in a multitude of relevant scenarios: parking lot, open space, highway, suburban and urban canyon. Upon separating the data into line of sight (LOS) and non-line of sight (NLOS) categories, our results show that obstructing vehicles cause significant impact on the channel quality. A single obstacle can cause a drop of over 20 dB in received signal strength when two cars communicate at a distance of 10 m. At longer distances, NLOS conditions affect the usable range of communication, effectively halving the distance at which communication can be achieved with 90\% chance of success. The presented results motivate the inclusion of vehicles in the radio propagation models used for VANET simulation in order to increase the level of realism and meaningfulness."

The paper was co-written by Meireles; Boban; Peter Steenkiste, faculty at CMU in Computer Science and Electrical Computer Engineering Departments; Ozan Tonguz, faculty at CMU in Electrical Computer Engineering Department; and João Barros, faculty at FEUP/IT.

October 2010