Linearization of nonlinear MISO channel

A Multiple Input Single Output (MISO) system based on Maximum Ratio Transmission (MRT) precoding with nonlinear Power Amplifiers (PAs) is considered. The nonlinear PAs distort the transmitted signal causing performance degradation. The common approach to mitigating nonlinear distortions is linearization of the PAs. For the MISO system we propose to apply a more generic approach in the form of an entire nonlinear MISO channel linearization, applied jointly for all PAs. It is shown that the results of this approach outperform those of the approach based on local linearization of each PA separately. An iterative technique is proposed to implement the entire MISO channel linearization. This technique requires knowledge of the channel state information and a model of the PAs at the transmitter. The performance of separate local and collective joint linearization is evaluated and compared in terms of the Symbol Error Rate (SER).