A peak to average power ratio reduction of multicarrier CDMA using selected mapping

MC-CDMA is a very promising technique for high-bit-rate and high capacity transmission in mobile communications. One disadvantage of multicarrier modulation is the high peak-to-average power ratio (PAPR) that results in nonlinear distortion at a high power amplifier (HPA) and the degradation of BER. Various methods for reducing PAPR have been proposed for OFDM. It is known that the partial transmit sequence (PTS) and the selected mapping (SLM) are effective for OFDM. The PTS has been applied to MC-CDMA and shown that it is effective for reducing the PAPR in MC-CDMA as well. However, the effects of SLM for MC-CDMA have not been clarified. We investigate the effects of SLM for MC-CDMA. We also investigate phase sequences in the SLM that is suitable for reducing the PAPR in MC-CDMA. We show that the SLM is more effective than the PTS at the same amount of side information.

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