Design and Performance Analysis of 3rd Order Kalman Filter Digital Frequency-Locked Loop

A three-dimensional Kalman filter based digital frequency-locked loop design approach is proposed for the carrier tracking of high dynamic global positioning system signals. The equivalence between Kalman filer and digital frequency-locked loop is derived. The transient-state and steady-state loop performance are analyzed. The simulation results show that the Kalman filter based digital frequency locked loop (DFLL) has much wider bandwidth in the transient-state than the fixed-gain DFLL while both have the same steady-state bandwidth, and the convergence time decreases a lot.