A Modified Constellation Extension Scheme with Error Correction Capability for Peak-to-Average Power Ratio Reduction in OFDM Systems

The constellation extension scheme-partial transmit sequence (CES-PTS) scheme in a 16-QAM OFDM system is a novel PAPR reduction method with low computational loads. The CES-PTS scheme reduces the complexity of the constellation extension scheme (CES). Although the CES-PTS scheme has lower IFFT operations than the CES, the signals transmitted by the CES-PTS scheme have no error correction capabilities. Therefore, this paper proposes a modified CES-PTS scheme, called BCM-CES-PTS, that combines block coded modulation (BCM) codes with the CES-PTS scheme to improve the error correction capability of the CES-PTS scheme. This study further proposes a new mapping of 16-QAM constellation extension scheme to improve the PAPR performance of the CES scheme. Simulation results show that the BCM-CES-PTS scheme has better PAPR performance than the CES-PTS scheme when the number of subblocks is the same.