Space, cost, and signal processing constraints, among others, often preclude the use of multiple antennas at wireless terminals. This paper investigates distributed decodeand-forward fixed relays (infrastructure-based relaying) which are engaged in cooperation in a two-hop wireless network as a means of removing the burden of multiple antennas on wireless terminals. In contrast to mobile terminals, the deployment of a small number of antennas on infrastructure-based fixed relays is feasible, thus, the paper examines the impact of multiple antennas on the performance of the distributed cooperative fixed relays. Threshold-based maximal ratio combining (MRC) and thresholdbased selection combining (SC) of these multiple antenna signals are studied and analyzed. It is found that the end-to-end (E2E) error performance of a network which has few relays with many antennas is not significantly worse than that which has many relays each with a fewer antennas. Obviously, the former network has a tremendous deployment cost advantage over the latter. It is also observed that the E2E error performance of a network in which the multiple antennas at relays are configured in SC fashion is not significantly worse than that in which MRC is used. For implementation, SC presents a significantly lower complexity and cost than a full-blown MRC. The analysis in this paper uses the versatile Nakagami fading channels in contrast to the Rayleigh model used in most previous works.

Additional Metadata
Keywords Cooperative diversity, Fading channels, Fixed wireless relays, Multiple antennas, Selection combining, Threshold maximal ratio combining
Persistent URL
Journal IEEE Transactions on Wireless Communications
Adinoyi, A. (Abdulkareem), & Yanikömeroǧlu, H. (2007). Cooperative relaying in multi-antenna fixed relay networks. IEEE Transactions on Wireless Communications, 6(2), 533–544. doi:10.1109/TWC.2007.05227