Abstract
A method of reducing a Peak-to-Average Power Ratio (PAPR) for an OFDM system is disclosed. Based on the fact that a cyclic shift of a signal in time domain is equivalent to an accumulated angle rotation of subcarriers of the signal in frequency domain, the method estimates a value of the cyclic shift using pilot signals to obtain a candidate signal with minimal PAPR. In the other embodiment, based on an even/odd grouping of a plurality of Zadoff-Chu sequences in time domain, the invention may also estimate a value of the cyclic shift using pilot signals to obtain a candidate signal with minimal PAPR. The method reduces the PAPR without transmitting side information in the OFDM system. Thus, the method can reduce the rate of decision error, the amount of candidate signals and searching complexity.