Two-Way Interference Channel Capacity: How to Have the Cake and Eat it Too

摘要

Two-way communication is prevalent and its fundamental limits are firststudied in the point-to-point setting by Shannon [1]. One natural extension isa two-way interference channel (IC) with four independent messages: twoassociated with each direction of communication. In this work, we explore adeterministic two-way IC which captures key properties of the wireless Gaussianchannel. Our main contribution lies in the complete capacity regioncharacterization of the two-way IC (w.r.t. the forward and backward sum-ratepair) via a new achievable scheme and a new converse. One surprisingconsequence of this result is that not only we can get an interaction gain overthe one-way non-feedback capacities, we can sometimes get all the way toperfect feedback capacities in both directions simultaneously. In addition, ournovel outer bound characterizes channel regimes in which interaction has nobearing on capacity.