Capacity of known interference channel with Gaussian modulations

In this paper, we investigate the capacity of known interference channel, where the receiver knows the interference data but not the channel gain of the interference data, assuming the use of Gaussian modulations. We first present a tight upper bound for the capacity of this known-interference channel. After that, we obtain the achievable rate of the channel with a blind known interference cancellation (BKIC) scheme in closed form. We prove that this achievable rate can approach the aforementioned upper bound in the high SNR regime. Moreover, it is much larger than the achievable rate of the traditional interference cancellation scheme. In particular, the achievable rate of BKIC continues to increase with SNR in the high SNR regime, while that of the traditional scheme approaches a fixed bound that does not improve with SNR.