Dummy sequence insertion (DSI) for PAPR reduction in the OFDM communication system

OFDM communications system is very useful for the high data rate transmission. However, power efficiency of HPA (high power amplifier) is very poor, since there should be a large back-off because of the high PAPR (peak-to-average power ratio) of the OFDM signal. Otherwise, OFDM signal may be distorted by the nonlinear HPA. In this paper, we propose a DSI (dummy sequence insertion) method for PAPR reduction. The complementary sequence and the combination of the correlation sequence belong to the dummy sequence. Flipping technique can be combined into DSI method to effectively lower the PAPR reduction. Also, PAPR threshold technique escalates the processing speed. Unlike the conventional PTS (partial transmit sequence) and SLM (selected mapping) methods, the specified dummy sequence is inserted only for PAPR reduction and any kind of side information is not necessary. So, BER of the DSI method is independent of the error in the dummy data sequence. Although the DSI method is not better than the conventional PTS and block coding methods with respect to the PAPR reduction performance, the DSI method improves the BER performance than the conventional PTS and is even more spectrally efficient than the conventional block coding for PAPR reduction.