高动态下导频辅助的GNSS信号比特同步方法

为了提高高动态条件下接收机对全球卫星导航系统定位信号的比特同步性能,基于新一代民用信号包含数据信号和导频信号的结构,提出一种比特同步方法。以比特跳变的候选位置为起点,将数据信号的相干累加值和导频信号的相干累加值的共轭相乘,并将共轭相乘的结果进行相干累加和非相干累加,根据不同候选位置为起点的非相干累加值判断比特跳变的实际位置。理论和仿真结果证明:该方法能够有效消除高动态条件下的多普勒频偏,比特同步性能优于传统方法。

Pilot signal assisted GNSS signal bit synchronization method under high dynamic condition

In order to improve the bit synchronization performance of the global navigation satellite system receiver under high dynamic conditions, a new method of bit synchronization is proposed based on the new civil signals’ structure including data signals and pilot signals. Starting from the candidate points of bit transition, the data signal coherent integrations values are multiplied with the conjugation of pilot signal coherent integration values. The outputs are coherent accumulated and noncoherent accumulated, and the real bit transition point is detected by the noncoherent accumulated values starting from different candidate points of bit transition. Theoretical analysis and computer simulation results prove that the proposed method can effectively eliminate the influence of doppler frequency shift under the high dynamic conditions, and its synchronization performance is better than the traditional bit synchronization method.