An Efficient Linear Companding Approach for PAPR Reduction in Multi-User MIMO-OFDM Systems

Orthogonal Frequency Division Multiplexing (OFDM) technology and massive Multiple-Input Multiple-Output (MIMO) technology have become the current two key core technologies of fifth-generation mobile communication (5G) and beyond fifth-generation mobile communication (B5G) systems. One of the challenges in multi-user (MU) MIMO-OFDM systems is the high peak-to-average power ratio (PAPR) of the signals. The high PAPR problem limits the efficiency of the power amplifier (PA) and leads to a larger distribution of signal. In this work, a low algorithmic complexity PAPR reduction scheme, i.e., a continuous piecewise linear companding (CPLC) scheme, is developed for the MU-MIMO-OFDM systems. In addition, the parameter ranges are discussed and the analytical simulations yield a set of parameters that improve the overall performance of the MIMO-OFDM system. The experimental results demonstrate that the CPLC algorithm allows for a trade-off between performance and complexity by allowing for very fine-grained control of the PAPR suppression level, bit-error rate (BER), and out-of-band (OOB) radiation performance. This leads to CPLC based MU-MIMO-OFDM antenna systems with lower PAPR and BER, as well as better OOB radiation performance.