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在空间通信中，信号面临远距离传输和高动态相对运动，其中，远距离传输带来很低信噪比（SNR, signal-to-noise ratio），而高动态相对运动则引起载波高动态多普勒频偏。为解决低信噪比问题，传统捕获方法需要长时间累积很多接收信号。但是，在长时间累积过程中，高动态多普勒频偏会导致严重的能量扩散问题。针对上述问题，提出了一种两阶段稀疏（TSS, two-stage-sparse）算法来捕获载波多普勒频偏。该算法首先利用粗捕获结果构造粗稀疏搜索范围，然后选择若干个较大元素来构建精稀疏搜索范围，最后搜索最大元素作为捕获结果。由于稀疏范围仅覆盖很窄的频率区间，该算法能够滤除更多的噪声干扰，从而辅助信号元素成为最大元素。理论分析和仿真结果也表明，所提TSS算法能够显著提高多普勒频偏的捕获概率。

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Copyright of Research & Exploration in Laboratory is the property of Research & Exploration in Laboratory and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)