Linear Massive MIMO Precoding Based on Nonlinear High-Power Amplifier

Large-scale multiple-input multiple-output (MIMO) system has the advantages of high energy efficiency and spectrum utilization. But using some cheap hardware may cause some problems, such as nonlinearity of the high power amplifier (HPA). When HPA works in the nonlinear region, it will affect the received signal and greatly reduce the performance of the system. In this paper, we first study the impact caused by nonlinear HPA, and then we optimize the traditional precoding algorithm to design an improved precoding algorithm which can reduce the impact. The simulation results show that the proposed algorithms perform better in bit error ratio and system capacity compared to the block of diagonalization (BD) precoding algorithm and forced zero (ZF) precoding algorithm, especially in the condition of high signal to noise ratio (SNR). So we can draw the conclusion that the algorithms proposed in this paper are able to reduce the impact caused by nonlinear HPA to the system.