Symmetric Semideterministic Relay Networks With No Interference at the Relays

A symmetric semideterministic relay network is introduced, generalizing Aref networks. In the considered model, there is no interference at the relays, but the links from the source and the relays to the sink are interfering and nondeterministic. An achievable rate is determined for an arbitrary number of relays, based on symmetric relaying and simultaneous partial and backward decoding at the sink. The information expressions of the achievable rate match those of the standard cut-set bound, but the set of probability distributions is substantially different. We also study a wireless example of the defined network where nondeterministic links are replaced with fading AWGN channels, and obtain its ergodic capacity with phase fading when phase information is locally available at the sink.