Evaluation of Doppler Frequency Aiding for GPS/INS Integration System

摘要

High dynamic condition will cause Doppler shit acutely,then digital carrier loop may fail to track signal and wrongdemodulation may occur in GPS receiver. So the designof tracking loop becomes a crux problem in designing ofsoftware receiver under high dynamic environment. TheInertial Navigation System (INS) and GPS are highlycomplementary to each other. Besides, the MEMS IMU ispreferred in an integrated GPS/INS system due to thelower cost, lower power-consumption and smaller size.So the full fusing INS with GPS can meet the highaccuracy, high continuity and high reliability navigationrequirements. Ultra-tight integration changes the structureof traditional GPS tracking loops. It can enhancereceiver’s signal processing and anti-jamming capability.This paper evaluates the performance of Dopplerfrequency aiding for GPS/INS integration systems. Firstly,the principles of the tracking loops which would be usedin the software-defined GPS receiver are reviewed.Secondly, the experiment platform for GPS/INSintegration is elaborated, and both hardware and softwarerequirements for GPS/INS integration are analyzed.Finally, the algorithm based on the receiver’s trackingloop is designed. The tracking performance, such astracking noise and frequency requirement by using thisproposed scheme is evaluated. The results of this paperwill have a potential contribution to the GPS/INS ultratightintegration implementation.