针对雷达常规线性调频(LFM)信号对强鞘套环境下再入航天器跟踪性能较差的问题,研究了相位编码波形对再入航天器的跟踪测量方法。相较LFM 信号,相位编码信号的模糊函数为图钉状,距离和多普勒分辨率高,不存在距离-多普勒耦合效应。利用鞘套与目标本体空间位置相同而速度不同的特点,当鞘套信号较弱、本体信号较强时,可以在目标本体多普勒滤波器中检测到目标,实现目标在空间和多普勒域的精确定位;当鞘套信号强于本体目标信号甚至淹没本体信号时,可以在鞘套的多普勒滤波器中选择信号较强的通道,借助鞘套实现目标本体的精确定位,从而完成对目标的跟踪测量。相位编码信号可为常规LFM 信号探测等离子鞘套目标提供有力补充,改善对高速再入航天器的跟踪测量效果。

Aiming at the poor tracking performance of radar using conventional linear frequency modulation (LFM) signal for reentry flight target under strong sheath environment, the detection and tracking performance of radar using phase-encode waveform for spacecraft during the process from sheath appearance to continuous enhancement was studied. Compared with LFM signal, the ambiguity function of phase-coded signal is pushpin shape, and the range and Doppler resolution of phase-encode signal are higher, so there is no range-Doppler coupling effect. When the sheath signal is weak and the body signal is strong, the Doppler filter of the body can be used to detect the target. When the signal intensity of the sheath is stronger than the signal intensity of the body, the channel of the strongest Doppler filter of sheath can be selected to detected the target, so the target can be accurately located by detecting the sheath, and complete the tracking measurement of the target. The phase coded signal can provide a powerful supplement to the conventional LFM signal to detect the sheath target and improve the tracking and measurement for the spacecraft in blackout area.

TN927