High-performance High Dynamic GPS Receiver Tracking Algorithm Research

As the global positioning navigation systems rarely subject to limitations of time andspace, which is widely used in various fields. Especially in the military field, related productsincreasingly focused on fast, high-precision features, high dynamic GPS receiver technologyhas been put forward higher requirements. As in the highly dynamic environment, the receiverreceives having a large Doppler or Doppler rate of change, which is an enormous challenge totrack the signal. Because code ring the Doppler offset can be eliminated carrier ring, therefore,this paper focuses on the design of carrier tracking algorithm under high dynamic scenes. Themain research work is as follows:First, this paper on the basis of analyzing phase-locked loop basic principles, study thedifferent order carrier tracking loop tracking of dynamic signals effects and simulationanalysis.Then, based on the relationship between frequency-locked loop and phase-lock looperror and the loop parameters, Derive the optimal loop bandwidth solution method and thecarrier loop gain control algorithm based on a lookup table is designed. The simulation resultsshow that the algorithm makes loop transient signal response time decreases, the ability totrack the dynamic strengthened.Then, focus on the analysis results of frequency-locked loop compared to phase-lockedloop, on the basis of phase-locked loop with more precision but weak characteristics of thecapacity dynamic, Designed a combination of carrier tracking loop control strategy based ona weighted algorithm. The algorithm by detect the size of the dynamic, use a weightedalgorithm to combine phase-locked loop and frequency-locked loop into a new compositeloop. The simulation results show that carrier can work normally with the dynamic indexes ofacceleration up to150g and jerk up to50g/s．Then, in the above analysis of phase-locked loop and frequency-locked loop having theopposite characteristics, Designed a high dynamic carrier loop tracking algorithm basedswitching strategy. The algorithm adds loop switching strategy module into the conventionalloop, so the loop is more stable when switched. Simulation results show that high dynamiccarrier tracking loop algorithm based the loop switching strategy Significantly reduceswitching frequency and jitter，Compared to the traditional loop，switching frequencyreduced by82%when the carrier signal strength is45dB-Hz, with5g and10g of accelerationdoing uniformly accelerated motion scenes at different time periods.Finally, the modernization L2C signal tracking algorithm is studied in papers. Thesimulation results show that compared to the single-track CM or CL signal, L2C combined tracking algorithm has a smaller loop measurement error and better tracking performance.