干涉仪测LFM信号方向误差分析

Error Analysis of Measuring Direction of LFM Signal Using Interferometer

干涉仪在对线性调频(LFM)信号测向时需要由瞬时测频(IFM)接收机提供LFM信号的载频,以及干涉仪的鉴相器提供相位差数据,从而得到LFM信号的方位角。不考虑噪声时,瞬时测频(IFM)系统和干涉仪对LFM信号测频和测向时均存在误差。针对该问题,研究了相位干涉仪的测向原理和解模糊原理,建立了多基线干涉仪侦收LFM信号的模型,分析了产生测向误差的原因。通过大量的仿真实验验证了影响LFM信号测向误差的因素,为实际应用中分析干涉仪对LFM信号的测向以及快速无源定位提供了依据。

While finding direction of LFM signal using interferometer, carrier frequency of LFM signal pro- vided by instantaneous frequency measurement （IFM） receiver and phase difference provided by phase discriminator were needed, so that the azimuth of LFM signal was gotten. Be regardless of the noise, there are errors when the instantaneous frequency measurement （IFM） system and the interferometer have the frequency measurement of LFM signal. This paper first briefly introduced the direction finding principle and ambiguity resolution principle of phase interferometer. And then it set up a model of multiple baseline interferometers detecting LFM signal and analyzed the causes of direction finding errors. Finally through a lot of simulation experiments, this paper verified the factors that influence the error of LFM signal direction finding, which provides reference for analyzing direction quick passive location in application. finding of LFM signal using interferometer and