PAPR and OOBP of OFDM and their improvement by using self cancellation codings

This paper presents a theoretical characterization of nonlinear distortion effects in orthogonal frequency division multiplexing (OFDM) using polynomial cancellation coding (PCC) and symmetric cancellation coding (SCC). First, we clarify the shape of the transmitted signal for the PCC-OFDM and SCC-OFDM. Then, we study the effectiveness of both schemes to reduce the high Peak-to-Average-Power Ratio (PAPR) compared to the normal OFDM theoretically and by simulation. We first derive the cumulative distribution function (CDF) of PCC-OFDM and SCC-OFDM. Then, for the same bit rate, we compare the performance of the two schemes with the normal OFDM. We show the effect of clipping on the two schemes under additive white Gaussian noise channel and frequency selective Rayleigh fading channel. Also, we study the improvement of out-of-band power (OOBP) by SCC-OFDM. Our results show that the SCC-OFDM has less PAPR than the normal OFDM and far less than PCC-OFDM. Also, we show that, clipping destroys the performance of PCC-OFDM compared to the normal OFDM and SCC-OFDM. Next, it is shown that the spectral roll-off of OFDM signals can be improved by SCC and the resultant OOB power is much reduced.