被动雷达导引头宽带信号时差测角方法研究

Research on Angle Measurement Method Based on Time Difference of Broadband Signal by Passive Radar Seeker

随着雷达系统的综合化,信号带宽越来越宽是雷达信号辐射源的发展趋势。宽带信号时宽带宽积大,具有时差估计精度高的优势。利用该优势,研究了基于时差估计的无源导引头测角方法。利用傅里叶变换将宽带信号时差估计转换为频率估计获得较高的精度。通过理论推导出来该方法的时差估计精度表达式,进一步得出测角精度表达式。针对不同信号带宽做了时差估计精度仿真,以及不同时差精度、不同入射角情况下的测角精度仿真。仿真结果表明,该方法相对于干涉仪测角方法,不需要解相位模糊并且能够显著提高宽带信号测角精度。

Increasing signal bandwidth is the development trend of radar signal radiation source with the synthesis of the radar system. The wideband signal has the advantage of high accuracy of time difference estimation on account of large time-bandwidth product. The method of measuring the angle of passive radar seeker based on time difference estimation is studied based on this advantage. The Fourier transform is used to convert the broadband sig- nal time difference estimation into frequency estimation to obtain higher accuracy. The ex- pression of time difference estimation accuracy is deduced by theory and the expression of an- gle accuracy is obtained. The accuracy of time difference estimation is simulated for different signal bandwidth. The accuracy of angle estimation is simulated for different time differenceand different incident angle. The results show that this method can significantly improve the accuracy of the angle measurement respect to the interferometer angle measurement method without phase unwrapping.