An algorithm based on dynamic compensation for GNSS carrier tracking of weak signal

摘要

In traditional receivers, frequency locked loop (FLL) or phase locked loop (PLL) is used for carrier tracking. In addition, fast Fourier transform (FFT) is an alternative implementation of carrier tracking when receivers are stationary. This paper presents why those methods are unsuitable for weak signal tracking in practice and proposes an improved algorithm based on dynamic compensation and FFT. The relationship between the compensation step and FFT points is exploited to obtain the best integration time and FFT points. The peak value detection is also analyzed. Simulation results in the end show that the proposed algorithm is robust with the carrier-to-noise ratio (C/N0) of the input signal as low as 10dB/Hz.