An Adaptive Tuning Method of GNSS Carrier Tracking Loop for High Dynamic Application

摘要

In the Global Navigation Satellite System (GNSS) receiver, the carrierrntracking loop is prone to lose lock in high dynamic environment. Under thisrncondition the receiver cannot provide accurate navigation informationrnwithout reacquisition of the satellite signal. To improve the performance ofrnthe carrier tracking loops for high dynamic application, this paper proposesrnan adaptive tuning method of the fusion parameters of FLL and PLLrn(FAFPLL) based on the fuzzy logic control. An indicator is introduced torndefine the state of the carrier tracking loop. The weights of the PLL andrnFLL are adaptively adjusted according to the value of the indicator. Arndesigned fuzzy controller is employed to map the nonlinear function of thernindicator and fusion weights. In this way, the contributions of the FLL andrnPLL can be adaptively changed according to the indicator. A trajectory withrn60g acceleration and 25g jerks are designed to test evaluate the performancernof the proposed algorithm. The results presented by the comparisons of thernvalues of the indicator. The results demonstrated that he proposed methodrnimproves the performance of the carrier tracking loop for high dynamicrnapplication.