对GPSL1C/A与L2CM信号的联合捕获技术进行了研究,利用双码联合广义差分技术解决导航数据位周期引起的跳变问题,提高其捕获灵敏度。而后引入了乘性检测方式,提高相关检测量的峰峰比值与算法检测概率,使其更有利于实现微弱环境下信号捕获。实验结果表明,该技术比单码捕获技术灵敏度提高了3dB,在输入信噪比为-24dB,发生数据位跳变时,成功捕获到卫星信号,检测量峰峰比为5.23,比传统算法提高了4.25倍。

In this article, GPS L1C/A and L2CM code signal combined acquisition technology was studied, the double combined generalized difference acquisition technology was used to solve the problem of data bits jumping due to the cyclic of satellite navigation data, and improve the acquisition sensitivity. Then the multiplicative method was introduced to improve the detection probability and acquisition correlation ratio between the first main peak and the second one, making it is more suitable to achieve acquisition in weak environment. The experimental results show that this acquisition technology improves the sensitivity of 3 dB than single code acquisition technology, at the same time, the improved algorithm when under the condition of the input SNR is 24 dB, existing navigation data jump, it can capture signal successfully, the ratio of the first main peak to the second peak is 5.23, increasing by 4.25 times than the traditional algorithm.