研究了导航信息引起的比特反转对实时卫星导航接收机时域并行捕获结果的影响。基于接收机捕获原理,经过对圆相关运算的定量分析,提出了一种改进的并行捕获方法。由于导航信息引起的比特反转会减小捕获的相关峰值,传统的时域并行捕获方法很难得到准确的捕获结果。因此针对性地设计了类圆相关(MCC)算法,经理论分析后将FFT应用于类圆相关算法,得到了改进的时域并行捕获(MTPA)算法。仿真结果验证了改进算法的正确性,显示了MTPA算法的正确性和有效性。这种捕获算法解决了接收机捕获时比特反转问题,提高了实时卫星导航接收机的捕获性能。
The impact of the bit transition caused by navigation messages on the time parallel acquisition results of a real time satellite receiver was investigated. Based on the acquisition theory of the receiver and the quantitative analysis of the circular correlation operation, a modified parallel acquisition method was proposed. As the bit transition caused by navigation messages reduces the correlation peak value, thus the conventional time parallel acquisition method can hardly get correct results. A mimic circular correlation ( MCC ) algorithm was designed for this situation and the fast Fourier fransform (Fb-T)operation was applied to the algorithm based on theoretical analysis, then the modified time parallel acquisition (MTPA) algorithm was proposed. The simulation results validate the accuracy and effectiveness of the algorithm, which can solve the bit transition problem and improve the performance of the satellite navigation receiver.