SER Analysis and Joint Optimization in Nonlinear MIMO-OFDM Systems with Clipping

Signal clipping is one of the most efficient signal peak-to-average power ratio (PAPR) reduction schemes for MIMO-OFDM receivers. It significantly reduces the nonlinear distortion caused by the power amplifiers (PAs) in the transmitter but introduces clipping distortion at the same time. Although the optimization of PA nonlinear distortion or clipping distortion has been well studied in previous research, the joint system optimization with both the nonlinear distortion from the transmitter and clipping distortion from the receiver is still a blank due to the complex PA modeling. This paper simplified the PA model with inter-modulation product (IMP) analysis and derived the expression of the symbol error rate (SER) in nonlinear clipped MIMO-OFDM systems. Based on the derivation, we found the optimal system setting to reach SER lower bound when PA nonlinearity and clipping distortion are simultaneously considered. The functions and methodologies in this paper can be a useful reference for system-level optimization for clipped MIMO-OFDM systems.