Abstract: Selected mapping (SLM) algorithm uses Cross Entropy (CE) algorithm to get the most optimal sign sequence so that SLM can make the effect of PAPR Reduction achieve optimum. However, it needs too many times iterative computations, so it will increase the complexity of the algorithm. In order to solve this problem, a fast convergence factor in the CE-SLM algorithm was introduced to make the sampling probability converge to 0 or 1 quickly in the system, which reduced the iterative times of getting the optimal sign sequence. Computer simulation results show that the approved algorithm reduces the iterative times of getting the optimal sign sequence under the condition of having the same effect of reducing PAPR with the CE-SLM algorithm, eventually reducing the complexity of the algorithm effectively.

Key words: cross entropy, convergence factor, OFDM, PAPR