System and method for reducing peak-to-average power ratio in orthogonal frequency division multiplexing signals using reserved spectrum

摘要

A method and apparatus for reducing the peak to average power ratio of an OFDM signal. The method involves operating on the signal only after it is converted to the time domain where the signal is compared to a power threshold and any signal above the power threshold is considered undesirable. A reduced signal is produced by reducing the magnitude to the power threshold whenever it exceeds that threshold. The delta between the original signal and reduced signal is the clipped signal. The clipped signal is multiplied by a g-function, and then subtracted from the original signal to produce a first iteration of a peak-reduced signal. The process can then be repeated using the first peak-reduced signal in place of the original signal to produce the second iteration of a peak-reduced signal. This process can be repeated each time bringing the peaks closer to the power threshold. The g-function can be defined either to allow for per-symbol cyclic signal processing or non-cyclic processing that is symbol time independent.