Adaptive Clipping-Based Active Constellation Extension for PAPR Reduction of OFDM/OQAM Signals

摘要

The active constellation extension (ACE) based on clipping technique is a lossless, simple and attractive peak-to-average power ratio (PAPR) reduction technique in orthogonal frequency division multiplexing with offset quadrature amplitude modulation system. But, when the target clipping level is set below an initially unknown optimum value, we observe that it cannot achieve the minimum PAPR. To overcome this low clipping level problem, a novel ACE algorithm with adaptive clipping control is proposed in this paper. First, an adaptive strategy is used to control the size of clipping level A. Secondly, a novel step factor is adopted, to complete iterative computations in order to increase the convergence speed. Simulation results validate that the proposed algorithm has reduced the PAPR and improved the convergence speed significantly without any side information and any processing at the receiver end.