2009/08/07 by Rui Wang, Wang, Rui, Vincent K. N. Lau +3
Computer Science · Mathematics · #FOS: Computer and information sciences #Information Theory (cs.IT) #cs.IT #math.IT
paper · pdf · doi:10.48550/arxiv.0908.1004
arxiv created 2009/08/07 · arxiv updated 2009/12/01
In this paper, utilizing the relay buffers, we propose an opportunistic decode-wait-and-forward relay scheme for a point-to-point communication system with a half-duplexing relay network to better exploit the time diversity and relay mobility. For instance, we analyze the asymptotic throughput-delay tradeoffs in a dense relay network for two scenarios: (1) fixed relays with microscopic fading channels (multipath channels), and (2) mobile relays with macroscopic fading channels (path loss). In the first scenario, the proposed scheme can better exploit the multi-relay diversity in the sense that with K fixed relays and a cost of O(K) average end-to-end packet delay, it could achieve the same optimal asymptotic average throughput as the existing designs (such as regular decode-and-forward relay schemes) with K2 fixed relays. In the second scenario, the proposed scheme achieves the maximum throughput of Θ(log K) at a cost of O(K/q) average end-to-end packet delay, where 0<q≤ 1/2 measures the speed of relays' mobility. This system throughput is unattainable for the existing designs with low relay mobility, the proposed relay scheme can exploit the relays' mobility more efficiently.