BLER Performance of Circular 256QAM Schemes Considering Cubic Metric for DFT-Precoded OFDM

This paper presents the average block error rate (BLER) performance of circular 256QAM schemes considering a peak-to-average power ratio measure called a cubic metric (CM) for discrete Fourier transform (DFT)-precoded orthogonal frequency division multiplexing (OFDM) in multipath fading channels. Computer simulation results show that the required average received signal-to-noise power ratio (SNR) satisfying the average BLER of 10−2 considering the CM for the (16×16) circular 256QAM constellation is deceased by approximately 0.5 dB, and that for the (32×8) and (64×4) circular 256QAM constellations is deceased by approximately 0.3 dB compared to the rectangular 256QAM scheme when using reference signal (RS) based channel estimation. Therefore, we conclude that the circular 256QAM constellation with independent bit mapping to either the phase or amplitude information is effective in achieving a lower required average received SNR satisfying the target average BLER than that for rectangular 256QAM considering the CM in multipath fading channels.