Interference Channel with State Information

TL;DR

This paper investigates the capacity of a two-user interference channel with non-causal state information at transmitters, proposing coding schemes and active interference cancellation techniques to improve achievable rates.

Contribution

It introduces novel coding schemes for the state-dependent interference channel, including active interference cancellation and heuristic methods for various interference regimes.

Findings

Active interference cancellation enlarges the achievable rate region in strong and mixed interference cases.

Flexible power splitting improves performance in weak interference scenarios.

Proposed schemes outperform traditional methods in certain interference conditions.

Abstract

In this paper, we study the state-dependent two-user interference channel, where the state information is non-causally known at both transmitters but unknown to either of the receivers. We first propose two coding schemes for the discrete memoryless case: simultaneous encoding for the sub-messages in the first one and superposition encoding in the second one, both with rate splitting and Gel'fand-Pinsker coding. The corresponding achievable rate regions are established. Moreover, for the Gaussian case, we focus on the simultaneous encoding scheme and propose an \emph{active interference cancellation} mechanism, which is a generalized dirty-paper coding technique, to partially eliminate the state effect at the receivers. The corresponding achievable rate region is then derived. We also propose several heuristic schemes for some special cases: the strong interference case, the mixed interference case, and the weak interference case. For the strong and mixed interference case, numerical results are provided to show that active interference cancellation significantly enlarges the achievable rate region. For the weak interference case, flexible power splitting instead of active interference cancellation improves the performance significantly.