On Discrete Signaling and Treating Interference as Noise for Complex Gaussian Interference Channels

In this paper, we study the achievable rate performance and the design of using purely discrete input signaling and treating interference as noise (TIN) for the two-user complex Gaussian interference channel (G-IC), where the channel introduces random phase rotation for all links. To analyze the achievable rate performance under this scenario, we first look into the corresponding deterministic interference channel model and design schemes to achieve the entire capacity region under TIN. Then, we translate the scheme into a multi-layer superposition coding scheme based on discrete inputs for GIC and analyze the achievable rate under TIN. Our simulation results show that our scheme is capable of approaching the (outer bound of) capacity region of the complex G-IC and performs significantly better than Gaussian signalling with TIN.