Non-Line-of-Sight 2.6GHz Relay Backhaul Channel Performance: Field Test and Analysis

Relay technologies have been standardized in 3GPP long term evolution (LTE), and can be a useful tool for coverage extension in diverse deployments. The backhaul channel between the relay and its donor eNodeB is essential to the end-to-end relay performance. Recently there has been an increased interest in deployments with non-line-of-sight (NLoS) backhaul channel conditions. In this paper, the NLoS backhaul channel quality has been measured in the real field, and the results show that NLoS backhaul has obvious gain over donor-UE channel and can be good enough to support relay data forwarding. Rules of thumb for NLoS relay deployment are identified that can help to minimize the diffraction loss or to utilize the strong reflections to improve the channel quality.