Adaptive Clipping Active Constellation Extension for PAPR Reduction of OFDM/OQAM System

The Active Constellation Extension (ACE) based on clipping technique is a lossless, simple and attractive Peak-to-Average Power Ratio (PAPR) reduction technique. However, we observe it cannot achieve the minimum PAR when the target clipping level is set below an initially unknown optimum value. To overcome this low clipping ratio 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 considering the possible overlap, is adopted to complete iterative computations in order to increase the convergence speed. Simulation results verify that the modified algorithm has reduced the PAPR and improved the convergence speed significantly without side information and without any extra processing at the receiver end.