基于AFD的无线信道的时频表示

he wireless channel analysis is the premise and key to achieve stable signal transmission in wireless communication system. The traditional method is limited to single time domain impulse response or frequency domain power spectral density. Moreover, there is lack of effective methods in the analysis of the characteristics of high speed and fast time-varying channels. A new analysis algorithm for wireless channel is proposed based on adaptive Fourier decomposition. A model of wireless multipath channel based on Clarke model is constructed, and the expression of mono-component decomposition representation, instantaneous frequency, channel time-frequency distribution and power spectral density are processed by mathematical deduction with the time domain channel impulse response. The channel's joint time-frequency domain characteristics are presented entirely by the joint time-frequency signal representation function. The simulation results show that this algorithm can achieve time-frequency analysis of wireless channel accurately and reconstruct the original signal fast and efficiently with smaller energy error. The method can also provide important reference for the simulation and modeling of wireless channel.