مشخصات پژوهش

In the time division duplex (TDD) based multiuser Massive multiple input multiple output (MIMO) systems, uplink channel is estimated and the results are used in downlink for signal detection. Due to noisy uplink channel estimation, the downlink channel should also be estimated for accurate signal detection. For this purpose, recently, a blind method is presented, which assumes that a linear high power amplifier (HPA) is used in the base station (BS). In this paper, we extend this method to a scenario with a nonlinear HPA in BS, in which the Bussgang Decomposition is used for HPA modeling. In the proposed method, we will show that the average power of the received signal for each user is a function of channel gain, large scale fading, and nonlinear distortion variance. Therefore, the channel gain is estimated, which is required for signal detection. The performance of the proposed method is analyzed theoretically. Simulation results show superior performance of the proposed method compared to that of the other methods in the literature.