关键词: 动中通系统, 载波频率跟踪, 锁频环, 广义延拓逼近算法

Abstract:

In order to improve the tracking precision of the satellite beacon signal in the Vehicle Satellite Communication on the Move(SOTM) system, an improved frequency tracking algorithm based on generalized interpolation fitting is proposed. The algorithm establishes a joint generalized extended model based on the peak of the signal's initial power spectrum. The boundary points of the extension region satisfy the interpolation conditions, and the best fitting is achieved in the element region. A one-dimensional discrete solution space of the model solution and the initial peak value is established, and the occurrence of the error in the direction of the valuation is effectively avoided, and the accuracy of the whole domain is improved. The results of the static and dynamic tracking of the satellite signal show that, in 40s integration time, the frequency tracking error can be limited to within plus or minus 2Hz. The algorithm achieves a certain dynamic performance, and can effectively improve the tracking accuracy of the carrier frequency tracking loop. The mathematical model of the generalized extended approximation frequency tracking algorithm is robust and of low complexity, and it can be realized in the premise of ensuring the dynamic performance and high tracking accuracy.

Key words: satellite communication on the move system, carrier frequency tracking, frequency-locked-loop, generalized extension algorithm