Peak to mean envelope power ratio of oversampled OFDM signals: an analytical approach

Orthogonal frequency division multiplexing (OFDM) has a large peak to mean envelope power ratio (PMEPR), which can result in significant signal distortion in the presence of nonlinear amplifiers. We show that the peak of the continuous envelope of the OFDM signal can be bounded by the maximum of the corresponding oversampled sequence. This fact is then used as the cornerstone of our two-part study. In the first part, statistical analysis is used to find the probability upper bound for the complementary cumulative distribution function of PMEPR. It is also proven that for a large number of subcarriers, only one redundant bit is necessary to limit the PMEPR within 10 % of its maximum value. In the second part, PMEPR estimation using oversampling and the fast Fourier transform is revisited. Here, we introduce a novel measure on the estimation error using an oversampled OFDM signal.

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