Performance Evaluation of MIMO-FTN Signaling under Multipath Fading Channels with PA Non-Linearity

In this study, we investigate the system performance of multiple-input multiple-output (MIMO) faster-than-Nyquist (FTN) signaling in the context of power amplifier (PA) non-linearity under multipath fading channels. We apply a more general MIMO-FTN precoded orthogonal frequency division multiplexing (OFDM) system model and provide the corresponding input-output relationship. For the PA model, the Rapp model is adopted to characterize the effect of non-linear distortion. We intend to investigate system performance through simulations under the following conditions: employing the MIMO configuration, utilizing the FTN signaling scheme, operating in a multipath environment, and accounting for PA non-linearity. This aspect has received relatively limited attention thus far. The simulation results reveal that FTN signaling still performs better than Nyquist signaling under the fixed transmission rate. For more comprehensive research, the effects of PA non-linearity are also simply demonstrated.