This paper presents a simple tracking filter circuit, which is applicable to Doppler radar sets and consists mainly of a switched bandpass filter and a phase-locked loop.

本文提出一种简单的跟踪滤波器电路，该电路可用于多普勒雷达，主要由开关式带通滤波器和锁相环组成。

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So the method that the Doppler frequency shift which obtained using theforecast approach aids the carrier tracking loop is proposed.

基于卫星轨道可模化、可预测的特性，提出了利用轨道预报得到的多普勒频移来辅助环路跟踪的新方法。

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