Research on Carrier Tracking Algorithm of INS-Assisted TC-OFDM Receiver with Fuzzy Control

摘要

The Time and Code Division-Orthogonal Frequency Division Multiplexing (TC-OFDM) system multiplexes the resources of mobile communication network and has an indoor distributed system, which can achieve indoor and outdoor wide-area coverage of positioning signal. Considering the indoor complex environment, dynamic stress or occlusion will cause a large fluctuation of positioning signal. In order to prevent the sudden change of carrier to noise ratio (CNR) and the loss-of-lock, this paper proposes an INS-assisted receiver carrier tracking algorithm. Through the introduction of fuzzy control, the observation output by the TC-OFDM receiver loop and INS are judged, the fusion switching of INS aided TC-OFDM receiver carrier tracking loop state is controlled, so as to improve the indoor environmental adaptability of the receiver and ensure the robustness of the deeply integrated system in a complex environment. The simulation results show that the algorithm can effectively prevent the loss-of-lock and the divergence of deeply integrated navigation system caused by the sudden change of CNR, and improve the dynamic performance of the receiver.