US Patent 7376197 Signal peak reduction circuit for non-constant envelope modulation signals

Circuits for reducing the signal peaks in telecommunications signals are described. The circuits and methods are preferably adapted for reducing the peak to average power ratio of non-constant envelope modulation signals. In one example the circuit includes a band-limiting filter for limiting the bandwidth of a data bearing signal and a predictive filter for predicting peaks in the data bearing signal at the output of the pulse-shaping filter. The circuit also includes a clipping processor for generating a compensation signal in response to one or more signal peaks predicted by the predictive filter and a signal combining device for applying the compensation signal to the data bearing signal prior to amplification of the data bearing signal.