Joint power and location optimization for analog network coding with multi-antenna sources

We consider a two-way relay system where multi-antenna sources employ beamforming to communicate bidirectionally via a single-antenna relay with analog network coding over Nakagami-m fading channels. We address the problem of both separate and joint optimization of power allocation and relay location in order to minimize the overall system outage probability. Our results demonstrate that separate optimization of relay location is more significant than that of power allocation to improve the overall system outage performance. We further emphasize that the joint optimization of power allocation and relay location can provide noticeable outage performance improvement over unbalanced per-hop fading conditions and/or nonidentical antenna configurations.