Effect of smooth non-linear distortion on OFDM BER

Non-linear distortion of OFDM signals can significantly increase the receiver BER. Currently, distortion analyses rely on simulation, not yielding insight into the problem, or apply to specific non-linearities only. In this paper, general analytic results are presented on the errors resulting from distortion. The results are applicable to smooth non-linear distortion of an OFDM signal, which is the most common distortion. Simple analytical expressions are derived which allows a designer to determine the BER before performing simulations. Further, it is shown that the error on each OFDM subcarrier is approximately equally large.