A new combined method of the block coding and predistortion for the nonlinear distortion compensation

This paper newly propose a combined method of the block coding and predistortion to compensate for the nonlinear distortion from the nonlinear amplifier in an OFDM communication system. Though the coding efficiency is low, the block coding has coding gain as well as limits the PAPR under 3 dB. Even if the predistortion is used, some amount of back-off is required to remove nonlinear distortion completely. We reduce the PAPR of an OFDM signal by the block coding and compensate for the nonlinear distortion by the predistortion. Therefore, the amount of required back-off is lowered so that power efficiency is improved compared to the case of predistortion only. The proposed combined method brings about 3 dB back-off gain than the single predistortion and block coding method when BPSK modulation is used and the number of subcarriers is 64. Also, when IBO (input back-off) is 3 dB, we can get 3 dB and 1 dB SNR gains than with only predistortion and block coding, respectively. Via the proposed method, even in the IBO of 2 dB, we can get a similar performance as the linear amplifier.