基于FRFT的伪码引信自适应LFM干扰对消方法

该文分析了LFM干扰对伪码引信相关输出的影响,当干扰强度超出伪码引信自身的抗干扰容限时,相关输出严重恶化,因此必须采取相应的抗干扰措施。考虑到LFM干扰与伪码引信有用信号间存在着强的时频耦合,提出了基于FRFT的自适应干扰对消方法。该方法首先对观察信号进行FRFT,估计干扰的特征参数,利用估计出的干扰参数构造自适应干扰对消器,将干扰去除。仿真表明,该方法能够有效滤除LFM干扰,相关输出得到显著改善,该方法对单分量和多分量干扰均有效,不受交叉项影响。

The Method of Adaptive Time-varying Interference Cancellation based on FRFT for Pseudo-random Coded Fuze

The effect of LFM interference on pseudo-random coded fuze system is analyzed. It is found that the correlation output is deteriorated when the interference power is larger than the anti-interference limit of the fuze system. It is very necessary to excise the above interference. Because there is strong time and frequency coupling between the interference and useful signal, so the method of adaptive time-varying interference cancellation based on FRFT is proposed. The characteristic parameters of interferences are obtained by FRFT. Then the adaptive interference canceler is designed according to the estimated interference parameters. Simulation results show that the above method can effectively excise LFM interference and the correlation output is improved obviously. This method is appropriate for both single component interference and multi-component interferences and it can not be affected by across items.