CN104808230A - Real-time precise point positioning method based on satellite clock and R-orbit error mixed estimation - Google Patents

Abstract

The invention discloses a real-time precise point positioning method based on the satellite clock and R-orbit error mixed estimation. A real-time satellite clock error estimation terminal and a mobile station client terminal are adopted. The method includes that the real-time satellite clock error estimation terminal estimates the satellite clock errors in real time through broadcast Ephesus and regional CORS continuous observation data and transmits to a mobile station through a mobile network rapidly; the mobile station client terminal receives GNSS observation data and acquires and decodes satellite clock error data through the mobile network, and the precise point positioning is performed after data p reprocessing. By the aid of the method, the positioning precision and convergence time of precise point positioning are improved and increased significantly on the basis of the IGS real-time data flow method, the small-scale CORS application is supported, and the limitation that satellite orbit determination requires a large range of ground stations is overcome; a user of the mobile station only receives the real-time satellite clock error correcting data instead of precise orbit data, and the network communication load is reduced.

Description

The real-time accurate one-point positioning method of a kind of star clock and R-orbit error hybrid estimation

Technical field

The present invention relates to GLONASS (Global Navigation Satellite System) (GNSS) field of satellite location, single poor Static Precise Point Positioning between particularly satellite clock correction inverting, GNSS star.

Background technology

Static Precise Point Positioning (Precise Point Positioning, PPP) is frontier theory and the hot issue in present satellites navigator fix field.PPP technology utilizes the correcting information of parameter field to realize precision positioning, can realize hi-Fix in any position by a dual-frequency receiver under global ITRF framework.The realization of this technology relies on two differential mode formula could obtain the present situation of high precision position information by changing, and can break away from the region limits relying on terrestrial reference station relative positioning and bring, have important and wide application prospect.In PPP solution process, orbit error and the satellite clock correction of satellite cannot pass through model correction, also cannot be eliminated by the mode of difference between star, therefore need to calculate according to the observation data of ground tracking station net, and the precision of satellite orbit and clock correction product directly affects PPP calculation accuracy, be the key and the key problem that realize Static Precise Point Positioning.

Conventional P PP research adopts third-party Precise Orbit and clock correction to carry out Static Precise Point Positioning usually, and precise satellite tracks as maximum in current application and clock correction are provided by IGS center.This series products has obvious retardation time and fixing sampling time interval usually, and can obtain after precise ephemeris as final in IGS takes 12-18 days, quick ephemeris needs 17-41 hour, and ultrafast ephemeris needs 3-9 hour.Even the real-time stream product that IGS up-to-date at present provides, also there is the retardation time of about 30 seconds in track and clock correction product, directly uses the needs that cannot meet PPP real-time resolving; The sampling interval that real-time stream product is fixed cannot meet the application needs of the carrier such as car and boat, aircraft high sampling rate; The stability of broadcasting of real-time stream product is subject to the factor impacts such as such as network communication.All in all, based on the PPP localization method of third-party Precise Orbit and clock correction product, be suitable for carrying out algorithm research afterwards, be difficult to the needs meeting location in real time.

Summary of the invention

Goal of the invention: for above-mentioned prior art, the real-time accurate one-point positioning method of a kind of star clock and R-orbit error hybrid estimation is proposed, can the observation data of abundant application region CORS, avoid the time delay and data stream instability problem that use third party's Precise Orbit and precise clock correction to exist.

Technical scheme: the real-time accurate one-point positioning method of a kind of star clock and R-orbit error hybrid estimation, comprises the steps:

Step 1), real-time satellite clock bias estimation end uses region CORS observation data, independently estimates satellite clock correction, by satellite clock correction and radial orbit error hybrid estimation in conjunction with broadcast ephemeris, be absorbed the satellite clock correction product of broadcast ephemeris radial orbit error, is specially:

According to region CORS observation data, set up GPS double frequency without ionospheric combination observation model:

$\begin{array}{c}\mathrm{\Δ}{P}_{\mathrm{IF}}=-\mathrm{\μ}\·\mathrm{\Δr}+\mathrm{\μ}\·\mathrm{\Δs}+\mathrm{cd}{t}_r-c{\mathrm{dt}}^s+M\·\mathrm{zpd}+{\mathrm{\ϵ}}_{P_{\mathrm{IF}}}\\ \mathrm{\Δ}{L}_{\mathrm{IF}}=-\mathrm{\μ}\·\mathrm{\Δr}+\mathrm{\μ}\·\mathrm{\Δs}+\mathrm{cd}{t}_r-c{\mathrm{dt}}^s+M\·\mathrm{zpd}+A_{\mathrm{IF}}+{\mathrm{\ϵ}}_{L_{\mathrm{IF}}}\end{array}---\left(1.1\right)$

Wherein, c represents the light velocity; Δ P _iF, Δ L _iFindicate the observation residual error of the pseudorange code without ionospheric combination, carrier phase respectively; A _iFrepresent that carrier phase is without ionospheric combination blur level; μ, Δ r and Δ s represent vector of unit length, survey station approximate coordinates correction, satellite approximate coordinates correction between the star of station respectively; Dt _rrepresent receiver clock-offsets; Dt ^srepresent satellite clock correction; M and zpd represents troposphere mapping function and Zenith tropospheric wet stack emission; with represent corresponding observation noise;

According to described formula (1.1), by the mode cancellation receiver clock correction error term cdt of difference between star _r, survey station approximate coordinates correction Δ r and satellite approximate coordinates correction Δ s, set up based on double frequency without ionospheric combination star between difference observation model:

$\begin{array}{c}\mathrm{\Δ}{P}_{\mathrm{IF}}^{i-j}=M^{i-j}\·\mathrm{zpd}-c({\mathrm{dt}}^{i-j}-{\mathrm{\Δ}}^{i-j}/c)+{\mathrm{\ϵ}}_{P_{\mathrm{IF}}}^{i-j}\\ \mathrm{\Δ}{L}_{\mathrm{IF}}^{i-j}=M^{i-j}\·\mathrm{zpd}+A_{\mathrm{IF}}^{i-j}-c({\mathrm{dt}}^{i-j}-{\mathrm{\Δ}}^{i-j}/c)+{\mathrm{\ϵ}}_{L_{\mathrm{IF}}}^{i-j}\end{array}---\left(1.2\right)$

Wherein, n is the gps satellite number of observation; J is GPS reference satellite, and (i-j) represents that satellite i and satellite j does difference between star, wherein i=1,2,3...n, i ≠ j; Δ ^i-jdifference value between the star of expression satellite i and satellite j radial orbit error; (dt ^i-j-Δ ^i-j/ c) represent the satellite clock correction absorbing radial orbit error;

According to described formula (1.2), order set up the error equation estimating satellite clock correction:

$\left[\begin{array}{c}{v}^{1-j}\\ v^{2-j}\\ v^{3-j}\\ ...\\ v^{n-j}\end{array}\right]=\left[\begin{array}{cccccc}{M}^{1-j}& c& 0& 0& 0& 0\\ M^{2-j}& 0& c& 0& 0& 0\\ M^{3-j}& 0& 0& c& 0& 0\\ ...& ...& ...& ...& ...& ...\\ M^{n-j}& 0& 0& 0& 0& c\end{array}\right]\left[\begin{array}{c}\mathrm{zpd}\\ {\mathrm{dt}}_{1-j}^s\\ d{t}_{2-j}^s\\ {\mathrm{dt}}_{3-j}^s\\ ...\\ {\mathrm{dt}}_{n-j}^s\end{array}\right]-\left[\begin{array}{c}\mathrm{\Δ}{L}_{\mathrm{IF}}^{1-j}\\ \mathrm{\Δ}{L}_{\mathrm{IF}}^{2-j}\\ \mathrm{\Δ}{L}_{\mathrm{IF}}^{3-j}\\ ...\\ \mathrm{\Δ}{L}_{\mathrm{IF}}^{n-j}\end{array}\right]---\left(1.3\right)$

Wherein, v ^i-jdifference value between the star of expression satellite i and satellite j observation equation residual error; represent that satellite i and satellite j observes difference value between the star of residual error without ionospheric combination;

According to the error equation of described formula (1.3), Kalman filtering is used to resolve, the real-time satellite clock correction of the radial orbit error that has been absorbed;

Step 2), after encoding to described real-time satellite clock correction, by mobile network's real-time broadcasting to mobile station user;

Step 3), mobile station user receives observation data, broadcast ephemeris, and obtains described real-time satellite clock correction data by mobile network and decode; Mobile station user, according to described observation data, broadcast ephemeris and decoded real-time satellite clock correction, uses Kalman filtering to carry out PPP in conjunction with differential mode type single between star and resolves, obtain final positioning result.

Beneficial effect: the real-time accurate one-point positioning method that the invention discloses a kind of star clock and R-orbit error hybrid estimation, real-time accurate list based on star clock and R-orbit error hybrid estimation is located and is made up of real-time satellite clock bias estimation end and mobile station user end: real-time satellite clock bias estimation end utilizes the Continuous Observation data of broadcast ephemeris and region CORS to estimate satellite clock correction in real time, is broadcast rapidly to rover station by mobile network; Mobile station user end receives GNSS observation data on the one hand, is obtained satellite clock difference data and is decoded on the other hand, carry out Static Precise Point Positioning after data prediction by GPRS network or mobile network's terminal.Use the method that the present invention proposes, the positioning precision of PPP and convergence time comparatively use IGS real-time stream to be significantly improved; Support CORS application on a small scale, overcome the restriction that Satellite Orbit Determination needs land station on a large scale; Mobile station user only needs receive real-time satellite clock error correction data and without the need to Precise Orbit data, reduce network service burden.

Accompanying drawing explanation

Fig. 1 is the inventive method process flow diagram;

Fig. 2 is the U.S. CORS website distribution plan that embodiment is chosen;

A and b in Fig. 3 be respectively in net P175 station based on real-time stream and the PPP positioning result figure based on star clock and radial orbit error hybrid estimation;

A and b in Fig. 4 be respectively the outer P091 of net stand based on real-time stream and the PPP positioning result figure based on star clock and radial orbit error hybrid estimation;

Fig. 5 is that the PPP of website in net locates N, E, U direction positioning error statistical graph respectively;

A and b in Fig. 6 is that the PPP of website in net locates convergence time and error in point measurement statistical graph respectively.

Embodiment

Below in conjunction with accompanying drawing, the present invention is further described.

As shown in Figure 1, the real-time accurate one-point positioning method of a kind of star clock and R-orbit error hybrid estimation, first real-time satellite clock bias estimation end uses region CORS independently to estimate satellite clock correction (track employing broadcast ephemeris), track and the clock correction of satellite is not distinguished in estimation procedure, by satellite clock correction and radial orbit error hybrid estimation, the clock correction product of the broadcast ephemeris radial orbit error that is absorbed; Then real-time satellite clock bias estimation end is encoded to satellite clock difference data and stored in database, is broadcast to mobile station user by mobile network; Mobile station user termination receives satellite clock difference data by mobile network and decodes, after carrying out data prediction, carrying out Static Precise Point Positioning in conjunction with broadcast ephemeris while receiving GNSS observation data.Concrete steps are as follows:

Step 1), real-time satellite clock bias estimation end uses region CORS observation data, independently estimates satellite clock correction, by satellite clock correction and radial orbit error hybrid estimation in conjunction with broadcast ephemeris, the satellite clock correction product of the part that is absorbed broadcast ephemeris orbit error, is specially:

According to region CORS observation data, set up GPS double frequency without ionospheric combination observation model:

$\begin{array}{c}\mathrm{\Δ}{P}_{\mathrm{IF}}=-\mathrm{\μ}\·\mathrm{\Δr}+\mathrm{\μ}\·\mathrm{\Δs}+\mathrm{cd}{t}_r-c{\mathrm{dt}}^s+M\·\mathrm{zpd}+{\mathrm{\ϵ}}_{P_{\mathrm{IF}}}\\ \mathrm{\Δ}{L}_{\mathrm{IF}}=-\mathrm{\μ}\·\mathrm{\Δr}+\mathrm{\μ}\·\mathrm{\Δs}+\mathrm{cd}{t}_r-c{\mathrm{dt}}^s+M\·\mathrm{zpd}+A_{\mathrm{IF}}+{\mathrm{\ϵ}}_{L_{\mathrm{IF}}}\end{array}---\left(1.1\right)$

Wherein, c represents the light velocity; Δ P _iF, Δ L _iFindicate the observation residual error of the pseudorange code without ionospheric combination, carrier phase respectively; A _iFrepresent that carrier phase is without ionospheric combination blur level; μ, Δ r and Δ s represent vector of unit length, survey station approximate coordinates correction, satellite approximate coordinates correction between the star of station respectively; Dt _rrepresent receiver clock-offsets; Dt ^srepresent satellite clock correction; M and zpd represents troposphere mapping function and Zenith tropospheric wet stack emission; with represent corresponding observation noise;

According to described formula (1.1), because the coordinate at area reference station is accurately known, co-ordinates of satellite is also considered as given value, by the mode cancellation receiver clock correction error term cdt of difference between star _r, survey station approximate coordinates correction Δ r and satellite approximate coordinates correction Δ s, set up based on double frequency without ionospheric combination star between difference observed reading model:

$\begin{array}{c}\mathrm{\Δ}{P}_{\mathrm{IF}}^{i-j}=M^{i-j}\·\mathrm{zpd}-c({\mathrm{dt}}^{i-j}-{\mathrm{\Δ}}^{i-j}/c)+{\mathrm{\ϵ}}_{P_{\mathrm{IF}}}^{i-j}\\ \mathrm{\Δ}{L}_{\mathrm{IF}}^{i-j}=M^{i-j}\·\mathrm{zpd}+A_{\mathrm{IF}}^{i-j}-c({\mathrm{dt}}^{i-j}-{\mathrm{\Δ}}^{i-j}/c)+{\mathrm{\ϵ}}_{L_{\mathrm{IF}}}^{i-j}\end{array}---\left(1.2\right)$

Wherein, n is the gps satellite number of observation; J is GPS reference satellite, and (i-j) represents that satellite i and satellite j does difference between star, and wherein i=1,2,3...n, i ≠ j, as M ^i-jrepresent the M of satellite i and satellite j on duty for the week between difference value; Δ ^i-jdifference value between the star of expression satellite i and satellite j radial orbit error; (dt ^i-j-Δ ^i-j/ c) represent the satellite clock correction absorbing radial orbit error;

According to described formula (1.2), order set up the error equation V=AX-L estimating satellite clock correction, be specifically unfolded as follows formula:

$\left[\begin{array}{c}{v}^{1-j}\\ v^{2-j}\\ v^{3-j}\\ ...\\ v^{n-j}\end{array}\right]=\left[\begin{array}{cccccc}{M}^{1-j}& c& 0& 0& 0& 0\\ M^{2-j}& 0& c& 0& 0& 0\\ M^{3-j}& 0& 0& c& 0& 0\\ ...& ...& ...& ...& ...& ...\\ M^{n-j}& 0& 0& 0& 0& c\end{array}\right]\left[\begin{array}{c}\mathrm{zpd}\\ {\mathrm{dt}}_{1-j}^s\\ d{t}_{2-j}^s\\ {\mathrm{dt}}_{3-j}^s\\ ...\\ {\mathrm{dt}}_{n-j}^s\end{array}\right]-\left[\begin{array}{c}\mathrm{\Δ}{L}_{\mathrm{IF}}^{1-j}\\ \mathrm{\Δ}{L}_{\mathrm{IF}}^{2-j}\\ \mathrm{\Δ}{L}_{\mathrm{IF}}^{3-j}\\ ...\\ \mathrm{\Δ}{L}_{\mathrm{IF}}^{n-j}\end{array}\right]---\left(1.3\right)$

Wherein, v ^i-jrepresent differentiated observation equation residual error between satellite i and satellite j star; represent differentiated between satellite i and satellite j star and observe residual error without ionospheric combination;

Estimate in the error equation of satellite clock correction, unknown parameter comprises troposphere and to wet component delay, satellite clock correction.Because system adopts single differential mode type between star, and carrier wave is only used to position, therefore total n-1 observation equation.In design matrix A battle array, first is classified as troposphere wets component delay d _tropcoefficient; Other after first row are classified as the coefficient of satellite clock correction.According to the error equation of formula (1.3), Kalman filtering is used to resolve, the real-time satellite clock correction of the radial orbit error that has been absorbed;

Step 2), after encoding to described real-time satellite clock correction, by mobile network's real-time broadcasting to mobile station user; Be specially: real-time satellite clock correction is encoded, is stored into database; Real-time satellite clock correction real-time network service after coding is broadcast.

Step 3), mobile station user receives observation data, broadcast ephemeris, and selects obtain real-time satellite clock correction data by mobile network and decode according to actual conditions; After mobile station user carries out data prediction to observation data, broadcast ephemeris, decoded real-time satellite clock correction, use Kalman filtering to carry out PPP in conjunction with differential mode type single between star and resolve, obtain final positioning result.

The present embodiment is chosen on August 8th, 2013 stand observation data of 15s sampling rate of U.S. CORS and is tested, and therefrom selects wherein 4 websites to carry out networking, carries out star clock and radial orbit error hybrid estimation obtains satellite clock correction product required when PPP locates.The network of quadrilaterals length of side that four networking websites are configured to is respectively 100km, 110km, 101km, 82km, selects 15 websites to be used for the accuracy test of PPP location as rover station in addition.The observation data result of 1h before this experimental analysis, height cutoff angle is 10 °, draws out the distributing position of each networking website and rover station in fig. 2, amounts to 20 websites.Wherein, base station 4 (triangle represents), nets interior 5 rover stations and outer 10 rover stations (circle represents) of net.Net outer rover station to choose by different distances, distance networking central point distance is 511.6km farthest.

The inside and outside single station analysis result of net: in networking, net is outer respectively chooses website P175, a P091 and analyze, the satellite clock correction product of the regional reference station network star clock utilizing the present invention to propose and radial orbit error hybrid estimation, carry out real-time PPP location in conjunction with broadcast ephemeris, and be located result and compare with the real-time PPP result based on real-time stream adopting RTKLIB software to obtain.

As can be seen from Fig. 3 and Fig. 4, the PPP resultant error curve difference that the employing two kinds of methods of standing at P175 station and P091 obtain comparatively greatly, adopts the positioning precision based on the PPP method of star clock and radial orbit error hybrid estimation to be obviously better than the PPP result of real-time stream.As can be seen here: the new departure adopting the present invention to propose at this website is feasible, compared with the PPP method based on real-time stream, N direction all can reach degree of precision, on E and U direction, new method result is better.Can be found out by the precision comparing the inside and outside website of net, can not only be applied to preferably based on star clock and the satellite clock correction product of radial orbit error hybrid estimation and net interior website, the survey station apart from networking 300km can also be applied to.

Website result statistics in net: adopt the calculation accuracy of the PPP scheme based on star clock and radial orbit error hybrid estimation to add up website in net further, this experiment is chosen and is netted interior 5 websites and carry out precision statistics.Netting interior 5 survey stations adopts based on star clock and the PPP method of radial orbit error hybrid estimation and the PPP method based on real-time stream respectively, add up the time within each error convergence to 10cm of standing firm, and the RMS value of the rear deflection error of convergence and error in point measurement, the result index of comparative analysis two kinds of methods.

As can be seen from Fig. 5, Fig. 6: net the positioning result that interior 5 websites adopt the PPP method based on star clock and radial orbit error hybrid estimation to obtain, compare the PPP method based on real-time stream, use 5 survey stations of new method to be all improved significantly in speed of convergence and positional accuracy.

Point location error RMS value and convergence time in the net of table 1 two schemes

Count the positioning result of two schemes in Table 1, adopt new method to obtain the positional accuracy at 5 stations generally higher than the PPP result of real-time stream; Convergence time is shortened greatly.It can thus be appreciated that website adopts broadcast ephemeris can realize real-time PPP in conjunction with the clock correction product of star clock and radial orbit error hybrid estimation to locate in net, higher positioning precision and speed of convergence faster can be reached.

Net outer website result statistics: in order to test the new method range of application of website and positioning precision offline further, precision statistics is carried out to outer 10 survey stations of net, these websites are chosen from the near to the remote successively according to the distance to networking center, are distributed between 190km to 511.6km successively.To 4 survey station coordinate averaged of networking as starting point, choose 10 outer websites of net from the near to the remote successively, based under the PPP of real-time stream and the PPP two schemes of star clock and radial orbit error hybrid estimation, add up N, E, U tri-deflection errors and all converge to 10 _ctime within m, and the positioning error RMS value after convergence in the 1h of location is in table 2.

The net exterior point positioning error RMS value of table 2 two schemes and convergence time

As can be seen from Table 2: by the survey station as far as nearly selected distance networking center 190km to 511.6km successively, when adopting the PPP method based on star clock and radial orbit error hybrid estimation, the precision of survey station on E and U direction obtains and increases substantially, in N direction, two schemes all can reach degree of precision, and precision is suitable.The speed of convergence of the outer all survey stations of net and positional accuracy, the PPP method comparing real-time stream is all significantly improved, and the average rate of convergence of new method improves and positional accuracy is all highly improved.

The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (1)

1. a real-time accurate one-point positioning method for star clock and R-orbit error hybrid estimation, is characterized in that: comprise the steps:

Step 1), real-time satellite clock bias estimation end uses region CORS observation data, independently estimates satellite clock correction, by satellite clock correction and radial orbit error hybrid estimation in conjunction with broadcast ephemeris, be absorbed the satellite clock correction product of broadcast ephemeris radial orbit error, is specially:

According to region CORS observation data, set up GPS double frequency without ionospheric combination observation model:

$\begin{array}{c}{\mathrm{\ΔP}}_{\mathrm{IF}}=-\mathrm{\μ}\·\mathrm{\Δr}+\mathrm{\μ}\·\mathrm{\Δs}+{\mathrm{cdt}}_r-{\mathrm{cdt}}^s+M\·\mathrm{zpd}+{\mathrm{\ϵ}}_{P_{\mathrm{IF}}}\\ {\mathrm{\ΔL}}_{\mathrm{IF}}=-\mathrm{\μ}\·\mathrm{\Δr}+\mathrm{\μ}\·\mathrm{\Δs}+{\mathrm{cdt}}_r-{\mathrm{cdt}}^s+M\·\mathrm{zpd}+A_{\mathrm{IF}}+{\mathrm{\ϵ}}_{L_{\mathrm{IF}}}\end{array}---\left(1.1\right)$

Wherein, c represents the light velocity; Δ P _iF, Δ L _iFindicate the observation residual error of the pseudorange code without ionospheric combination, carrier phase respectively; A _iFrepresent that carrier phase is without ionospheric combination blur level; μ, Δ r and Δ s represent vector of unit length, survey station approximate coordinates correction, satellite approximate coordinates correction between the star of station respectively; Dt _rrepresent receiver clock-offsets; Dt ^srepresent satellite clock correction; M and zpd represents troposphere mapping function and Zenith tropospheric wet stack emission; with represent corresponding observation noise;

According to described formula (1.1), by the mode cancellation receiver clock correction error term cdt of difference between star _r, survey station approximate coordinates correction Δ r and satellite approximate coordinates correction Δ s, set up based on double frequency without ionospheric combination star between difference observation model:

$\begin{array}{c}{\mathrm{\ΔP}}_{\mathrm{IF}}^{i-j}=M^{i-j}\·\mathrm{zpd}-c({\mathrm{dt}}^{i-j}-{\mathrm{\Δ}}^{i-j}/c)+{\mathrm{\ϵ}}_{P_{\mathrm{IF}}}^{i-j}\\ {\mathrm{\ΔL}}_{\mathrm{IF}}^{i-j}=M^{i-j}\·\mathrm{zpd}+A_{\mathrm{IF}}^{i-j}-c({\mathrm{dt}}^{i-j}-{\mathrm{\Δ}}^{i-j}/c)+{\mathrm{\ϵ}}_{L_{\mathrm{IF}}}^{i-j}\end{array}---\left(1.2\right)$

Wherein, n is the gps satellite number of observation; J is GPS reference satellite, and (i-j) represents that satellite i and satellite j does difference between star, wherein i=1,2,3...n, i ≠ j; Δ ^i-jdifference value between the star of expression satellite i and satellite j radial orbit error; (dt ^i-j-Δ ^i-j/ c) represent the satellite clock correction absorbing radial orbit error;

According to described formula (1.2), order set up the error equation estimating satellite clock correction:

$\left[\begin{array}{c}{v}^{1-j}\\ v^{2-j}\\ v^{3+j}\\ ...\\ v^{n-j}\end{array}\right]=\left[\begin{array}{cccccc}{M}^{1-j}& c& 0& 0& 0& 0\\ M^{2-j}& 0& c& 0& 0& 0\\ M^{3-j}& 0& 0& c& 0& 0\\ ...& ...& ...& ...& ...& ...\\ M^{n-j}& 0& 0& 0& 0& c\end{array}\right]\left[\begin{array}{c}\mathrm{zpd}\\ {\mathrm{dt}}_{1-j}^s\\ {\mathrm{dt}}_{2-j}^s\\ {\mathrm{dt}}_{3-j}^s\\ ...\\ {\mathrm{dt}}_{n-j}^s\end{array}\right]-\left[\begin{array}{c}{\mathrm{\ΔL}}_{\mathrm{IF}}^{1-j}\\ {\mathrm{\ΔL}}_{\mathrm{IF}}^{2-j}\\ {\mathrm{\ΔL}}_{\mathrm{IF}}^{3-j}\\ ...\\ {\mathrm{\ΔL}}_{\mathrm{IF}}^{n-j}\end{array}\right]---\left(1.3\right)$

Wherein, v ^i-jdifference value between the star of expression satellite i and satellite j observation equation residual error; represent that satellite i and satellite j observes difference value between the star of residual error without ionospheric combination;

According to the error equation of described formula (1.3), Kalman filtering is used to resolve, the real-time satellite clock correction of the radial orbit error that has been absorbed;

Step 2), after encoding to described real-time satellite clock correction, by mobile network's real-time broadcasting to mobile station user;

Step 3), mobile station user receives observation data, broadcast ephemeris, and obtains described real-time satellite clock correction data by mobile network and decode; Mobile station user, according to described observation data, broadcast ephemeris and decoded real-time satellite clock correction, uses Kalman filtering to carry out PPP in conjunction with differential mode type single between star and resolves, obtain final positioning result.