On Achievable Rate Regions for the Gaussian Interference Channel

Abstract

The complete characterization of the capacity region of a two-user Gaussian interference channel is still an open problem unless the interference is strong. In this work, we derive an achievable rate region for this channel. It includes the rate region which is achieved by time/ frequency division multiplexing (TDM/ FDM), and it also includes the rate region which is obtained by time-sharing between the two rate pairs where one of the transmitters sends its data reliably at the maximal possible rate (i.e., the maximal rate it can achieve in the absence of interference), and the other transmitter decreases its data rate to the point where both receivers can reliably decode its message. The suggested rate region is easily calculable, though it is a particular case of the celebrated achievable rate region of Han and Kobayashi whose calculation is in general prohibitively complex. In the high power regime, a lower bound on the sum-rate capacity (i.e., maximal achievable total rate) is derived, and we show its superiority over the maximal total rate which is achieved by the TDM/ FDM approach for the case of moderate interference. For degraded and one-sided Gaussian interference channels, we rely on some observations of Costa and Sato, and obtain their sum-rate capacities. We conclude our discussion by pointing out two interesting open problems.

On achievable rates of the two-user symmetric Gaussian interference channel

“…where inequality (8) correspond to the individual rate constraint of decoding the common messages w 1 at receiver 1 and w 2 at receiver 2, inequality (9) correspond to the individual rate constraint of decoding w 2 at receiver 1 and w 1 at receiver 2, and inequality (10) correspond to the sum rate constraint of jointly decoding both common messages w 1 and w 2 at receiver 1 and receiver 2.…”

Achievable bit rates of cognitive user with Vandermonde precoder in cognitive radio network

“…In practical OFDM systems such as IEEE 802.11a, c is at most 1 4 [10]. Hence, we set the simulation parameters as follows (see [13][14][15][16]). …”

Perfect Interference Alignment for K-user MIMO X Network

“…그러 나 여전히 간섭 채널이나 X 채널에서와 같이 많은 무선 네트워크에서의 정확한 capacity 특성은 알려져 있지 않다 [5]- [7]. 그에 대한 대안으로, 다중 이득이 라고도 알려져 있는 DOF (degrees of freedom)에 대 a.…”