【摘要】 频域陷波是直扩系统中一种常用的抗窄带干扰措施,但是会造成信号能量损失和信号失真,而信号失真导致的信噪比恶化为非线性失真,难以通过公式计算。提出了一种信号失真的计算方法,并通过Matlab仿真,分析对比了频域陷波在不同扩频比、不同调制方式及不同陷波位置时,信号失真导致的性能恶化,采用增大扩频比、降低调制阶数(如BPSK)等方式,可减小信号失真导致的性能恶化。更多还原

【Abstract】 Frequency domain notch is a popular approach to resist narrowband interference in direct sequence spread spectrum( DSSS) system,but it leads to signal energy loss and signal distortion,and the signal-to-noise ratio( SNR) deterioration caused by signal distortion is a kind of nonlinear distortion,which is difficult to calculate directly by formula. Therefore,a calculation method of signal distortion is proposed. Moreover,via Matlab simulation,the performance degradation caused by signal distortion in frequencydomain notch under different spread ratios,different modulations and different notch positions is analyzed and compared.It is concluded from the simulation results that the performance degradation caused by signal distortion can be reduced by increasing the spread ratio and lowering the modulation order( such as BPSK).更多还原