Relay Selection in Dual-Hop Vehicular Networks

In this letter, we investigate cooperative diversity with relay selection over cascaded Rayleigh fading channels. In particular, we analyze the performance of a relay selection scheme for cooperative vehicular networks with the decode-and-forward (DF) protocol. Only the “best” relay, which satisfies an index of merit, is selected. We ignore the direct transmission between the source (
S
) and its destination (
D
), and assume that the destination has perfect knowledge of the
S
→
R
and
R
→
D
channel gains. We study the performance of the underlying scheme in terms of outage probability and investigate its achievable diversity order.