一种全球定位系统弱信号捕获策略

摘要

Acquisition is a very important part of digital GPS receiver. The acquisition of weak GPS signal is a key point of the research of GPS algorithm. Two classic acquisition strategies, TONG strategy and NM strategy, are analyzed and compared. Considering the specialty of weak signal condition, a new acquisition strategy named Double Threshold(DT) strategy is proposed. The analysis and simulation indicate that it performs well under weak signal condition.%信号捕获是目前广泛应用的数字全球定位系统(GPS)接收机的重要部分，弱信号条件下的信号捕获过程是目前 GPS 接收机算法研究的重点。本文分析和比较了2种经典捕获检测策略(TONG捕获策略及 NM捕获策略)的性能，并针对弱信号条件下 GPS信号捕获的特点，提出了一种适用于弱信号条件下的捕获检测策略-双门限搜索检测策略。理论分析和仿真说明该策略在弱信号条件下具有较好的性能。