Peak-Power reduction in OFDM without explicit side information

We propose a novel method for reducing the peak–to–average power ratio (PAR) of the transmit signal before the power ampli£er in the transmitter. The method is based on the Selected Mapping (SLM) approach of [1]; in contrast to other schemes, SLM represents a method to ef£ciently reduce the PAR without introducing additional distortion in the transmit signal. This is accomplished by generating a set of candidate transmit signals, all representing the same information sequence. The candidate signals are then examined, and only the most favourable candidate in terms of the peak–power is transmitted. The proposed novel scheme elegantly solves an open problem with SLM, namely that the receiver needs highly reliable information about the transmitter’s choice of the candidate. Our method refrains from transmitting this side information explicitly. It requires some additional complexity in the transmitter, whereas the additional cost in the receiver is almost vanishing. Besides for OFDM, the proposed method is applicable for any digital transmission scheme