On the Gaussian Interference Channel with Unilateral Generalized Feedback

Overview & Synopsis

This paper studies the Gaussian interference channel with unilateral generalized feedback, a system where two source-destination pairs share the same channel and where one full-duplex source overhears the other through a noisy in-band link. A superposition coding scheme is shown to achieve a known outer bound to within a small number of bits for a subset of the weak interference regime, outside which more sophisticated coding techniques based on binning are conjectured to be needed. By using the generalized Degrees of Freedom (gDoF) as performance metric, unilateral generalized feedback is shown to strictly increase the gDoF region compared to the non-cooperative case only when the strength of the cooperation link is larger than a threshold, thus providing an indication on when cooperation among users is beneficial in practical wireless systems.