用连续均值剔除干扰(Consecutive mean excision,CME)算法可以抑制直扩系统中的数字窄带干扰,通过迭代更新门限值,可抑制50%带宽的数字窄带干扰。针对CME算法计算量大的缺点,利用FFT幅度谱的中心对称特性,提出了一种改进的更易于工程实...用连续均值剔除干扰(Consecutive mean excision,CME)算法可以抑制直扩系统中的数字窄带干扰,通过迭代更新门限值,可抑制50%带宽的数字窄带干扰。针对CME算法计算量大的缺点,利用FFT幅度谱的中心对称特性,提出了一种改进的更易于工程实现的CME算法。与常规的CME算法相比,改进的CME算法仅对部分幅度谱进行迭代更新,在减少运算量和节省存储空间的同时,能够保持良好的抑制性能。理论分析和数字仿真表明,改进算法可有效地抑制直扩通信系统中的数字窄带干扰,且实现简单。展开更多
A generalized approach for narrowband interference （NBI） suppression in direct sequence spread spectrum （DSSS） communication systems using adaptive infinite impulse response （IIR） filter is presented. The excisi...A generalized approach for narrowband interference （NBI） suppression in direct sequence spread spectrum （DSSS） communication systems using adaptive infinite impulse response （IIR） filter is presented. The excision filter coefficients depend on both the jammer power and its instantaneous frequency. The dependency of the filter construction on the jammer power is significant as it allows optimal tradeoff between interference removal and signal distortion by maximizing the receiver signal to noise ratio improvement（SNRI）. Instead of traditional adaptive line enhancer （ALE） estimator, a preferable NBI estimator-Fourier interpolation estimator （FIE） is proposed. Closed-form expressions of the SNR improvement and theoretical bit error rate （BER） based on the assumption that the output of the correlator is Gaussian distributed are both derived. Performance results obtained by numerical simulation are also presented and compared with theoretical results.展开更多
An improved polar exciser （IMPE） interference suppression method against broadband constant envelope binary phase shift keying （BPSK） interference is proposed. The disadvantage of traditional polar exciser （PE） ...An improved polar exciser （IMPE） interference suppression method against broadband constant envelope binary phase shift keying （BPSK） interference is proposed. The disadvantage of traditional polar exciser （PE） is the performance degradation when the power of interference is low, i.e., the threshold effect. The proposed improved PE （IMPE） algorithm can overcome the threshold effect of PE by introducing compression gain （CG） metric, which forces PE suppressor active only at larger jammer-to-signal ratio （JSR） and switch to matched filter （MF） at lower JSR. Theoretical analysis and numerical simulations show the exactness of CG as a switching metric and the validity of the IMPE algorithm.展开更多
文摘用连续均值剔除干扰(Consecutive mean excision,CME)算法可以抑制直扩系统中的数字窄带干扰,通过迭代更新门限值,可抑制50%带宽的数字窄带干扰。针对CME算法计算量大的缺点,利用FFT幅度谱的中心对称特性,提出了一种改进的更易于工程实现的CME算法。与常规的CME算法相比,改进的CME算法仅对部分幅度谱进行迭代更新,在减少运算量和节省存储空间的同时,能够保持良好的抑制性能。理论分析和数字仿真表明,改进算法可有效地抑制直扩通信系统中的数字窄带干扰,且实现简单。
基金Sponsored by the Beijing Municipal Natural Science Foundation(4052024)
文摘A generalized approach for narrowband interference （NBI） suppression in direct sequence spread spectrum （DSSS） communication systems using adaptive infinite impulse response （IIR） filter is presented. The excision filter coefficients depend on both the jammer power and its instantaneous frequency. The dependency of the filter construction on the jammer power is significant as it allows optimal tradeoff between interference removal and signal distortion by maximizing the receiver signal to noise ratio improvement（SNRI）. Instead of traditional adaptive line enhancer （ALE） estimator, a preferable NBI estimator-Fourier interpolation estimator （FIE） is proposed. Closed-form expressions of the SNR improvement and theoretical bit error rate （BER） based on the assumption that the output of the correlator is Gaussian distributed are both derived. Performance results obtained by numerical simulation are also presented and compared with theoretical results.
基金Beijing Municipal Natural Science Foundation (4052024)
文摘An improved polar exciser （IMPE） interference suppression method against broadband constant envelope binary phase shift keying （BPSK） interference is proposed. The disadvantage of traditional polar exciser （PE） is the performance degradation when the power of interference is low, i.e., the threshold effect. The proposed improved PE （IMPE） algorithm can overcome the threshold effect of PE by introducing compression gain （CG） metric, which forces PE suppressor active only at larger jammer-to-signal ratio （JSR） and switch to matched filter （MF） at lower JSR. Theoretical analysis and numerical simulations show the exactness of CG as a switching metric and the validity of the IMPE algorithm.
