Distribution of peak-to-average power ratio and its applications in OFDM systems with unequal power allocation

In this paper, we propose a general expression of the peak-to-average power ratio (PAPR) distribution in orthogonal frequency division multiplexing (OFDM) systems with unequal power allocation strategy, which is based on the extreme value theory for Chi-squared-2 process. The proposed general distribution of the PAPR depends on the number of the subcarriers, distribution of the power allocation and the amount of the total transmission power. To validate the analytical results, we conduct extensive experiments and the numerical results also show that the proposed distribution of the PAPR has a good agreement with that of OFDM systems with unequal power allocation strategy. Finally, we show an example of that the proposed distribution of the PAPR could be directly applied to design the OFDM systems with selective mapping technique to reduce the PAPR.