Research On Detection And Reparation Method Of Cycle-slip In Beidou High Precision Positioning

In recent years,the construction speed of Beidou satellite navigation system has been accelerating,and now it has the overall performance of the leading system in the world.With the progress of the society,the positioning accuracy of Beidou satellite navigation system is increasingly required in many fields,such as transportation,geography and disaster relief.However,the accuracy of satellite positioning will be greatly reduced due to the inevitable cycle-slip phenomenon in the carrier phase observations that high-precision positioning relies on.In view of this,this paper first analyzes the commonly used singlefrequency and dual-frequency cycle-slip detection and restoration methods,and then studies Beidou three-frequency cycle-slip detection and restoration methods based on the long wavelength,low ionospheric delay,low noise and other excellent characteristics of the Beidou three-frequency data combination.At the following,the main points and creations are listed:1.The principle of several commonly used single-frequency and dual-frequency cycleslip detection and repair methods were analyzed.The ability of several methods to detect and repair different types of cycle-slip were measured and studied at different sampling rates,and the advantages and disadvantages of each method were summarized.2.In view of the blind spots of cycle-slip detection in doppler method and ionospheric residual method respectively,a new combined method for detection and repair of cycle-slip was proposed,and the actual measurement and analysis of the method was carried out.The experimental results showed that the method effectively made up for the shortcomings of the two methods,and there is no insensitive cycle-slip.3.The reasons affecting the cycle-slip detection accuracy of the three-frequency pseudorange/phase combination method were analyzed,and the selection rules of the optimal combination coefficients are discussed.According to the selection rules,three combinations of nonlinear coefficient(0,-1,1),(-1,-5,6)and(-4,1,4)are determined.At last,the cycle-slip in the carrier phase observations at three frequency points are solved by simultaneous equations.4.In view of the failure detection of the insensitive cycle-slip of three frequency geometry-free phase combination method,this paper puts forward a new method of cycleslip detection and repair with two MW combinations and a three frequency geometry-free phase combination.Then the coefficient selection condition of the three frequency geometry-free phase combination was predetermined,and coefficient(1,1,-2)was determined as the three frequency geometry-free combination coefficient on the basis of the selection condition.Experimental results show that this method has a good effect of detection and repair for small,large and insensitive cycle-slip.