On the Capacity of the Symmetric Interference Channel With a Cognitive Relay at High SNR
The capacity of the Interference Channel with Cognitive Relay, a channel model which generalizes the broadcast, interference and cognitive interference channels, is still an open question. To make progress towards understanding this complex channel, the authors first consider the binary linear deterministic models that approximate the Gaussian channel at high SNR. They consider symmetric channel gains and show achievability of a tightened version of a previously known outer bound for almost all channel parameters. Of particular interest in this channel model is how the cognitive relay may be used to simultaneously relay as well as cancel/neutralize interference at two receivers.