A Novel Combined Control Loop Based on FLL-Assisted-PLL for Highly Dynamic Tracking

摘要

Compared with a single loop, a FLL-assisted-PLL (Frequency-locked Loop, FLL; Phase-locked Loop, PLL) tracking loop which integrates both the dynamic robustness of FLL and the accuracy performance of PLL has better carrier tracking performance. However, under highly dynamic conditions, its tracking ability still cannot meet the requirements. To overcome this problem, a novel combined control loop based on FLL-assisted-PLL is proposed in this paper. The combined control loop adjusts the action effects of FLL and PLL automatically according to the current tracking state without the need for decision processing, which makes full use of the characteristics of FLL and PLL. Simulation results demonstrate that the proposed combined loop does achieve a shorter convergence time and higher tracking accuracy than the traditional FLL-assisted-PLL tracking loop under significant dynamics.