Optimization of the GPS Receiver using higher order loops for High Dynamics

摘要

Conventional GPS receivers work well when the relative dynamics between the satellite and the receiver are less. However, in high dynamic environments the receivers no longer track the signals resulting in the loss-of-lock of GPS position. To address the'issue, in this paper, a new frequency-locked loop (FLL) assisted phase-locked loop (PLL) technique of higher order is introduced. Frequency pulling of second order FLL rectifies the higher dynamic frequency errors at the receiver and thus allows the third order PLL to lock on to the phase of dynamic signal with high accuracy. The proposed algorithm was implemented using Simulink and evaluated by simulated data sets. Results show that the proposed algorithm using frequency loop has improved performance when the input signal changes comprise large dynamic range.