Antenna selection with user scheduling in traffic-aware cellular two-way relay networks

We investigate the outage performance of a cellular multiuser two-way relaying networks (TWRNs), where a multi-antenna base station (BS) communicates with one of the several single-antenna mobile stations (MSs) via a single-antenna relay terminal. We employ antenna selection at BS coupled with MS selection to maximize the end-to-end signal-to-noise ratio (SNR). In view of asymmetric traffic requirements at the end terminals, we derive the tight closed-form overall outage probability (OOP) expression of the considered system under Rayleigh fading. We also derive an asymptotic outage behavior in high SNR regime to reveal the impact of asymmetric traffic and system parameters on the achievable diversity order. Moreover, we formulate an optimization problem of relay location to minimize the OOP of the considered system. Numerical and simulation results corroborate our theoretical analysis and findings, and also demonstrate that the optimal relay location has a significant impact on the OOP performance under asymmetric traffic demands.