A New Polar Coding Scheme for the Interference Channel

We consider the problem of polar coding for the 2-user discrete memoryless interference channel (DM-IC). Existing schemes are designed according to the original description of the Han-Kobayashi region, which involves two deterministic functions that map auxiliary random variables to channel inputs. Inspired by Chong et al.’s compact description of the Han-Kobayashi region, we propose a novel, simplified design of polar codes to achieve the Han-Kobayashi region which does not require the aforementioned mapping functions. We design two types of polar coding schemes and show that every point on the dominant faces of the Han-Kobayashi region can be achieved. We further extend our proposed schemes to discrete memoryless interference networks (DM-IN) and show that they in fact represent a heterogeneous superposition coding scheme with rate splitting, which can simplify the code design for DM-INs with private messages while still achieve the optimal rate region.