【摘要】 在北斗接收机的使用中，系统的高动态特性使得北斗卫星信号具有快速变化的多普勒平移和码相位，这提高了信号捕获的难度。目前，主流采用的PMF-FFT捕获方法需要消耗大量的硬件资源和运行时间，难以满足北斗接收机的速度要求。为了实现高动态场景下北斗信号快速变化的多普勒频移和码相位的捕获，提出了一种基于改进型PMF-FFT的捕获算法。在详细分析PMF-FFT数学理论的基础上，通过对单个码元内部进行积分存储，降低了捕获系统的相关器使用和噪声干扰。同时引入多路采样时钟，保证了码片积分的时钟条件。最后在北斗高动态仿真场景下，采用仿真测试了该算法与PMF-FFT算法的性能。结果表明，相比传统算法，该算法的噪声抑制比提高了约1.3 dB,运行时间缩短了约7%。因此，该算法能够减少相关器资源的使用并提高信噪比，适用于高动态条件下的北斗卫星信号捕获。更多还原

【Abstract】 In the use of Beidou receivers, the high dynamic characteristics of the system cause Beidou satellite signals to rapidly changing Doppler translations and code phases, which increases the difficulty of signal acquisition. The currently used PMF-FFT acquisition method consumes a large amount of hardware resources and running time, and is difficult to meet the speed requirements of Beidou receivers. In order to achieve Beidou signal acquisition in high dynamic scenarios, an capture algorithm based on improved PMF-FFT is proposed. Based on a detailed analysis of the mathematical theory of PMF-FFT, the correlator usage and noise interference of the acquisition system are reduced by integrating the internal storage of a single symbol. At the same time, multiple sampling clocks are introduced to ensure the clock conditions for chip integration. Finally, under the Beidou high dynamic scene, simulation is used to test the performance of this algorithm and the traditional algorithm. The results show that compared with the traditional algorithm, the noise suppression ratio of this algorithm is improved by about 1.3 dB and the running time is shortened by 7%. Therefore, this algorithm can reduce the use of correlator resources and improve the signal-to-noise ratio, and is suitable for Beidou under high dynamic conditions.更多还原