PAPR Reduction in OFDM System Using a New Quantum Genetic Algorithm

Abstract

Partial transmit sequence (PTS) is a classical method to reduce the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) systems. However, the computational complexity of PTS grows exponentially with the number of subcarriers. In order to obtain a reasonable BER performance/complexity ratio, a novel quantum genetic algorithm is proposed in this paper. On the one hand, the combination of PTS and the preset threshold can narrow the range of search. On the other hand, a new quantum crossover is applied in the update equation to maintain the population diversity and global convergence. In addition, a clonal selection and new quantum mutation is proposed to increase the convergence rate in this paper. Results of the simulation illuminate that the proposed algorithm can effectively solve the problem of high computational complexity of PTS. While maintaining the effect of reducing PAPR close to the full search algorithm, the computational complexity can also be reduced by 64%.