摘要：In satellite navigation systems, regenerative Pseudo-Noise (PN) is usually adopted to range but its navigation signal power is low, along with large external interference. In order to achieve real-time PN ranging, tracking loop lock detection becomes crucial. In conventional loop lock detection method, loop decision threshold (including discriminator and counter threshold) can’t adapt received Signal to Noise Ratio (SNR) which results in false positives. For the forementioned problem, this study proposes an optimized chip tracking loop locking detection method which derives composite code SNR based on the relationship between residual carrier, composite code signal and total signal power, then adaptively selects a suitable locking threshold according to the SNR estimation. Through the simulation analysis, the feasibility of the optimization method is verified, with the conclusion that loop quickly runs into detection lock under high SNR and judges if it is locked after stabilized tracking under low SNR.
