Partial Transmit Sequences based on Least Clipping Noise

摘要

The Gaussian distributed OFDM signal with high fluctuation introduces nonlinear distortion, out-of-band radiation due to strict requirement on linearity in power amplifier. In 1997, Muller and Huber proposed partial transmit sequences algorithm based on least PAPR (Peak to Average Power Ratio) in order to reduce the fluctuation. On the other hand, when dividing the sequences into more parts, the computation increases exponentially. Furthermore, this algorithm often focuses on the compression of the highest power, which does not mean that the overall system performance should be improved. This paper proposes a novel partial transmit sequences algorithm based on least clipping noise. Specifically, in the selection of optimal parameters in partial transmit sequences to modify the phases of input symbols, total clipping noise (nonlinear distortion) is considered instead of the highest power. This algorithm is extensively studied with the well-known model of power amplifier. It is shown that the system performance with 2 partitions based on least clipping noise is close to that with 3 partitions based on least PAPR, and performance with 3 partitions based on least clipping noise is even better than that with 4 partitions based on least PAPR. This way, the required computation is effectively reduced.