针对MBOC信号自相关函数多峰特性导致的捕获模糊问题和导航接收机对硬件资源的限制,提出了一种基于多峰能量累积的MBOC信号低复杂度无模糊捕获方法.该方法将MBOC信号与对应BPSK信号互相关结果中的两个峰值进行相干累积,实现无模糊捕获.通过理论计算与分析得出该无模糊处理方式在同样条件下捕获灵敏度更高.根据匹配滤波捕获模块设计和降采样后灵敏度损失分析,得出该捕获方法对应的匹配滤波器结构简单,且在降低了采样率后仍能保证较高的灵敏度.
In consideration of the ambiguity of the MBOC signal acquisition brought by the mult- peak autocorrelation function and the limitation of the satellite navigation receiver hardware resource, a low-complexity unambiguous MBOC signal acquisition method based on mult-peak power accumulation was proposed. By correlating the MBOC signal with the BPSK signal and coherently accumulating the two peaks, it realizes an unambiguous acquisition. According to the theoretical calculation, it claims that the sensitivity of the method is relatively high in the same condition. According to the design of the matched filter based acquisition engine and analysis of the sensitivity loss after down sampling, it indicates that the new method reduces the complexity but keeps the sensitivity at a low sampling rate.