Research on Windowing Technology of NC-OFDM System Based on Cognitive Radio

摘要

NC-OFDM is the main transmission mode of cognitive radio system. The windowing technique can speed up the attenuation of NC-OFDM out-of-band power spectrum and reduce the out-of-band interference of NC-OFDM symbols. Based on the distribution of subcarriers in NC-OFDM system, this paper firstly proposed the power interference model of the perceive users to authorized users. And the average relative interference power density is proposed as PnR→Lnfor the model. The interference power of the different window function is applied to the NC-OFDM system with the average relative interference power density as PnR→Lninterference with the smallest power SOCW window, combined with the receiver's BER performance and out-of-band power attenuation rate to select the SOCW parameters.