Patent ID: 8599961
Filing Date: 2013-12-03
Classification: H04B,H04L

Abstract:
1. A method for crest factor reduction of a multi-carrier signal comprising a plurality of single-carrier signals, the method comprising: sampling to detect time segments of the plurality of single-carrier signals prior to combining the plurality of single-carrier signals to form the multi-carrier signal, the sampling producing a plurality of sampled single-carrier signals; performing a joint potential peak detection on the plurality of sampled single-carrier signals and thus producing a temporal position of a possible peak in the multi-carrier signal, whereby the joint potential peak detection is carried out by determining a sum of absolute values of the plurality of single-carrier signals at a comparison temporal position to derive an absolute values sum, comparing the absolute values sum to a peak indicator threshold, and adopting the comparison temporal position as the temporal position of the possible peak in the multi-carrier signal, if the absolute values sum is greater than the peak indicator threshold; generating a plurality of cancellation pulses; injecting the plurality of cancellation pulses to the plurality of single-carrier signals at a plurality of temporal injection positions, the plurality of temporal injection positions corresponding to the temporal position of the possible peak in the multi-carrier signal; and combining the single-carrier signals to form a crest factor reduced multi-carrier signal, wherein the joint potential peak detection further comprises: finding an interval in which the absolute values sum is greater than the peak indicator threshold; determining values of the multi-carrier signal within the interval; and determining a maximum of the values of the multi-carrier signal and a maximum position of the maximum, and adopting the maximum position as the temporal position of the possible peak in the multi-carrier signal.