捕获算法对比研究

弱信号捕获是信号同步的关键技术，随着卫星导航应用范围越来越广，低信噪比下的信号捕获算法已经逐渐成为了捕获技术研究的热点。文中对低信噪比下的弱信号捕获算法进行了模型描述和性能定量分析，主要对相干积分算法、非相干积分算法和差分相干积分算法的处理增益及其对应的检测性能进行了理论分析和仿真比对。仿真结果表明，差分相干积分算法具有良好的处理增益性能，且对数据位跳变不敏感，适用于低信噪比下的信号捕获。

Comparison Study on Acquisition Algorithm

Weak signal acquisition is the key technology of signal synchronization. With the increasingly wide application range of satellite navigation, acquisition under the low SNR environment becomes the research focus. It specifies the models of weak signal acquisition algorithms ,and analyzes the performance of algorithms quantitatively. The main GNSS weak signal acquisition algorithms： coherent integration （COH） ,non-coherent integration （NCOH） ,differential coherent integration （DFC） are presented in detail. The comparison analysis on processing gain and detection performance of the three algorithms is conducted. Numerical simulations demonstrate that DFC obtains good processing gain and detection performance, and is insensitive to data transition, which can apply to weak signal acquisition.