Based On Time-frequency Analysis Of Interference Suppression Technology Research And Application

Because of the complexity in the present war, we should improve the anti-jam, anti-intercepted ability of the communication system.The DSSS system was firstly used in the military communication environment for its excellent abilities, but its performance was related to the spread gain. Under the limit of spectrum, we can not increase the spread gain of DSSS arbitrarily. On the other hand, the present research results were mainly about the narrowband interference mitigation, and the influence of wideband nonstationary interference for DSSS is more important, so we should research more noval anti-jam technology and systems in the military environment.To cancel the wideband nonstationary interference, the interference suppression technology based on the time-frequency distribution (TFD) property is proposed. In this paper we used the LFM signals as the jam modle, combined with the Turbo codes, the performance of a novel DSSS system under different strong jam was estimated by the theoretical analysis and the simulation validation. At the sme time, the DSP implementation unit models of the key algorithms are given for the novel communication system.The simulation results demonstrate that the interference suppression technology based on the TFD property can cancel the interference excellently, so towards the disadvantage of DSSS in spectrum efficiency, we propose a new system which is called bandwidth efficient multi-access system.Compared to the DSSS, this system is bandwidth efficient, and by the user identification matrix design at the transmitter and the iterative SISO detection technology at the receiver, it can achieve the single-user performance when multi users accessed, and the interference suppression technology based on the TFD can perform excellently in this system.