Multihop Best-Relay Selection for Vehicular Communication Over Highways Traffic.

Multihop relaying is a transmission technique that splits the communication link between the source and the destination into several, possibly shorter, hops for extended coverage, improved reliability, and less power consumption. Previous works on multihop communications use the assumption of frequency-flat and quasi-static fading, which can be justified only for narrowband systems resulting from stationary or quasi-static channels. In this paper, we extend multihop relaying into vehicular communication in highways. We deploy a precoded transmission over multihop vehicle-to-vehicle links that is characterized by time- and frequency-selective fading. We propose and investigate a transmission scheme where traveling vehicles are allowed to relay signals via neighboring vehicles to the final destination. With the aid of the precoded transmission and best-relaying vehicular selection, we succeeded to extract the rich diversity gains that are inherent in these types of doubly selective fading channels (i.e., through time and frequency dimensions), and through space dimension using cooperative transmission. We developed a mathematical model and derived a tight upper-bound expression for the pairwise error probability for future studies and analysis. Computer simulations are used to verify the correctness and accuracy of the derived analytical error. [ABSTRACT FROM AUTHOR]