On clipping for peak power reduction of OFDM signals

The effect of digital envelope clipping on the peak power of the bandlimited OFDM signal is studied. The system consists of the concatenation of digital clipping of the OFDM signal with and without oversampling and bandpass filtering, followed by the ideal low-pass filter. It is shown that without oversampling, the clipped OFDM signal may suffer considerable peak power regrowth compared to those with oversampling. To justify this empirical result, the distribution of the instantaneous power in the digitally clipped OFDM signals without oversampling is theoretically analyzed by its lower bound.