Cooperative Linear Combining on Quantize-Forward Relay Channel With $M$-Ary Phase Shift Keying
Xianglan Jin · IEEE Transactions on Vehicular Technology · 2022
This work considers quantize–forward (QF) relay channels with$M$-ary phase shift keying at the source and$q$-bit uniform phase quantization at the relay. A cooperative linear combining (CLC) detection which linearly combines the received signals at the destination is proposed in the QF relay channel by deriving an equivalent signal-to-noise ratio for the source-relay-destination link. Furthermore, the proposed detection is simplified by approximating$Q$function in two directions: small$q$and large$q$. The CLC detection and its simplified version are also extended to multi-relay channels. Simulation results verify that the CLC and simplified CLC detections achieve reasonable performance with less complexity than the maximum-likelihood detection. It demonstrates that applying$(\log _{2} M+2)$-bit uniform phase quantization at the relay and the simplified CLC detection at the destination can be an appropriate choice in terms of performance, complexity, and memory.