A Low-Complexity Scheme to Reduce the PAPR of an OFDM Signal Using Sign-Selection Algorithms

This paper considers the use of the sign-selection technique to reduce the peak-to-average power ratio (PAPR) of an orthogonal frequency division multiplexing (OFDM) signal. In the sign-selection technique, a set of subcarrier signs is selected to significantly reduce the PAPR statistics for OFDM signals. However, the considerable computational complexity for an exhaustive search over all combinations of 2L different sign patterns is a potential problem for practical implementation, where L is the number of subcarriers. To reduce the computational complexity while still improving the PAPR statistics, we introduce the quantum-inspired evolutionary algorithm (QEA), an effective algorithm that solves various combinatorial optimization problems, to determine a good set of subcarrier signs. The computer simulation results show that as compared to the conventional selected mapping (SLM) scheme and the cross-entropy (CE) method, the proposed QEA obtains the desirable PAPR reduction with low computational complexity.