A peak power reduction scheme with parity carrier for multicarrier modulation

This paper proposes a method which reduces the peak-to-mean power ratio (PMPR) of the multicarrier modulation signal by providing a subcarrier for peak power reduction outside the information band. The proposed method includes the addition of a redundant signal, that is, parity carrier, in order to reduce the peak power of the multicarrier signal when its envelope exceeds a given threshold. The parity carrier for peak power reduction is placed outside the band of the multicarrier signal and can be easily removed in the receiver. It is shown by a computer simulation that when two carriers for peak power reduction are added to the multicarrier signal with eight carriers, the PMPR after the peak power reduction approaches 4.7 dB. It is also shown for the case in which the power amplifier has little nonlinearity that an outband spectrum density of -50 dB can be achieved by applying the proposed method for a back-off of 4.7 dB.