直扩系统时变单音干扰抑制的新方法

针对直接序列扩频通信系统中的时变单音干扰，提出了一种频域干扰估计时域对消的新方法。在系统中，将干扰信道建模为时变衰落信道。该算法首先在频域对时变单音干扰信号参数进行估计，然后对时变单音干扰进行重构和对消，推导了理论误码率公式。理论分析和仿真结果表明，该算法性能由干扰功率和多普勒频移等因素决定。在频率选择性衰落信道下，当信噪比为20dB，扩频增益为16，干扰信道多普勒频移为100Hz时，该算法可以抑制20dB(干信比)的单音干扰。 

A Novel Time-Varying Single Tone Jamming Suppression method for DSSS System

In this paper, a frequency domain interference estimation and time domain cancellation method is proposed to suppress the time-varying single tone jamming (STJ) in direct sequence spread spectrum (DSSS) system. The interference channel is modeled as a time-varying fading channel in the system. In this method, the parameters of time-varying STJ are estimated in frequency domain, and then it is reconstructed and subtracted from the raw data. Furthermore, the BER expression is analyzed to assess the performance of the proposed method. Simulation results demonstrate the effectiveness of the method in mitigating time-varying STJ and approaching the interference-free performance limit over practical ranges of STJ power levels and mobility levels. In the frequency selective fading channel, when signal-to-noise ratio (SNR) is 20 dB, the spreading gain is 16, Doppler shift of the interference channel is 100 Hz, jamming-to-signal power ratio (JSR) is less than 20 dB, the STJ can be suppressed by the proposed method.