GNSS Ambiguity Rapid Resolution Aided By INS And Its Implementation

In the process of Global Navigation Satellite System(GNSS)kinematic relative positioning,if the signal is blocked or interfered,the GNSS satellite signal tracking will lose lock.It is a hot spot and a critical issue to fix the integer ambiguity rapidly and accurately for recapturing signal,which is also the key of processing high accuracy GNSS kinematic relative positioning.Considering the high position accuracy of Inertial Navigation System(INS)and its ability not to be interfered by external condition,the search space of ambiguity and the time to resolve the integer ambiguity can both be reduced when we adopted the high precision positioning results of INS as a priori information.This paper uses the coordinate information produced by INS to solve the ambiguity estimation problems,Firstly,the accuracy of INS is analyzed.Secondly,GNSS ambiguity resolution aided by INS is processed and the time to fix the integer ambiguity is used to measure how INS aiding affects the ambiguity resolution process.The main contents of this paper include the following aspects:1.This paper introduces coordinate systems of INS,explain the principle and process of the inertial navigation using ECEF navigation equations and verify the algorithm by using the simulation data.The results show that INS has a high precision in a short time,but the error will accumulate with time and increase exponentially.2.This paper introduce the algorithm of GNSS carrier phase relative positioning and integer ambiguity resolution,and introduce the Least-square AMBiguity Decorrelation Adjustment(LAMBDA)in detail.The simulation results show that the algorithm is correct and reliable.3.the real time data is used to calculate the fixed time of integer ambiguity of GNSS and INS respectively.The results show that the time to resolve the integer ambiguities after lose lock has been significantly shortened with the assistance of INS;Instantaneous integer ambiguity resolution is found to be possible within two seconds after GNSS data outages.