The complex non-stationary signals are most often used in modem radar and communication systems. It must perform the tasks of envelope detection and intra-pulse feature analysis for radar pulse classification and identification. Time-frequency analysis is an effective tool for modem signal processing, and often applied to analyze and process non-stationary signals. Several methods of time-frequency analysis are presented, reconnaissance are also discussed and simulated. Simulation results show the and their applications in the radar signal effectiveness of these methods.