Capacity Bounds and Sum Rate Capacities of a CLass of Discrete Memoryless Interference Channels

TL;DR

This paper determines the sum-rate capacity of a class of discrete memoryless interference channels with weak interference, showing they are equivalent to degraded channels and deriving bounds for channels with mixed interference.

Contribution

It introduces capacity bounds and sum-rate capacities for a new class of discrete memoryless interference channels, extending Gaussian channel results to discrete settings.

Findings

Sum-rate capacity is achieved with single user detection.

Capacity region is equivalent to certain degraded interference channels.

Derived capacity bounds for channels with mixed interference.

Abstract

This paper studies the capacity of a class of discrete memoryless interference channels where interference is defined analogous to that of Gaussian interference channel with one-sided weak interference. The sum-rate capacity of this class of channels is determined. As with the Gaussian case, the sum-rate capacity is achieved by letting the transceiver pair subject to interference communicate at a rate such that its message can be decoded at the unintended receiver using single user detection. It is also established that this class of discrete memoryless interference channels is equivalent in capacity region to certain degraded interference channels. This allows the construction of capacity outer-bounds using the capacity regions of associated degraded broadcast channels. The same technique is then used to determine the sum-rate capacity of discrete memoryless interference channels with mixed interference as defined in the paper. The obtained capacity bounds and sum-rate capacities are used to resolve the capacities of several new discrete memoryless interference channels.