CN101770033B - Fixing method of ambiguity network between CORS and system station - Google Patents

Abstract

The invention discloses a fixing method of an ambiguity network between CORS system stations, which comprises the following steps: first, a wide-lane ambiguity float solution is worked out with the linear combination of carrier wave and pseudorange, the mean is solved through multi-epoch according to the long-wave features of wide-lane ambiguity, to determine the wide-lane ambiguity integer solution; and then the delay dry weight of a troposphere is estimated through a Neill model, L1 ambiguity is separated by the independent combination of an ionosphere, so as to determine L2 ambiguity; and finally accuracy test of ambiguity resolution is carried out. The method provided by the invention can fix the baseline ambiguity between CORSs in a short time, is quick, stable and easy to be implemented in projects.

Description

Integer ambiguity network fixing means between the CORS system station

Technical field

The present invention relates in the GNSS network differential positioning system baseline integer ambiguity network calculation method between reference station, relate in particular to integer ambiguity network fixing means between CORS (CORS) system station, belong to GNSS network differential positioning field.

Background technology

GNSS network differential location technology is the hot technology in present satnav field, be widely used in the industries such as mapping and survey of territorial resources, network differential technology take virtual reference station technology (VRS) as representative is risen, so that set up the recent tendency that reference station network formula GPS service system becomes Current GPS technology application development.The VRS technology is as the GPS real-time dynamic positioning technology under many reference stations environment, it is the network RTK location technology that integrates Internet technology, wireless communication technique, computer networking technology and GPS technology, also be wide, the most successful representative high-tech achievement of current application, the VRS technical system has represented the afterwards developing direction of location technology of new generation of conventional RTK.

The online of baseline integer ambiguity fixedly is the prerequisite that realizes the VRS technology between reference station.Growth along with parallax range between reference station, the systematic error correlativity weakens even disappears, systematic error residue in the double difference observation increases rapidly, cause being difficult to correctly determining integer ambiguity, so that bearing accuracy decline, thereby the online of long baseline integer ambiguity fixedly is the important technological problems of restriction VRS/RTK real-time, reliability between reference station.The long baseline Ambiguity Solution Methods of domestic and international many scholar's centerings has been carried out many research work, mainly contain following certain methods: 1, Gao Xingwei has proposed single epoch of the searching for integer cycle method (Gao Xingwei between reference station, 2002), the main thought of the method is solving equations not, utilize directly that the survey station coordinate is known, blur level is searched for for these three conditions of the linear relationship between integer and the double frequency integer ambiguity, but its principle and imperfection, reliable be not so the method is used widely; 2, the Fast Carrier Phase Ambiguity Resolution of Zhou Letao is another kind of effectively long baseline blur level fixing means (Zhou Letao, 2006), and it resolves thinking is to use parallel filtering and expand wave technology (Sun, 1999; Chen, 2000): first to the parallel Kalman filtering of carrying out of the irrelevant blur level of wide lane ambiguity and ionosphere, because the long wave characteristic in wide lane, must be found the solution first in the filtering, again with it as given value substitution ionosphere independent combination, make ionosphere independent combination wavelength expand 0.107m to by 0.006m, at last by estimating to fix blur level and calculating parameter static solution to the estimation of zenith tropospheric delay hygroscopic water amount with to the integer of L1 blur level, but this method requires high for model parameter in the Kalman filtering.

Summary of the invention

The present invention is directed to the deficiency of prior art, proposed a kind of fast and be easy to that baseline integer ambiguity network calculation method is integer ambiguity network fixing means between the CORS system station between the reference station of Project Realization, the technical scheme of the method is:

Integer ambiguity network fixing means between the CORS system station, it is characterized in that: at first utilize the linear combination of carrier wave and pseudorange to find the solution wide lane ambiguity floating-point solution, long wave characteristic according to wide lane ambiguity, determine wide lane ambiguity integer solution by finding the solution mean value many epoch, i.e. wide lane integer ambiguity; Then estimate the dried hygroscopic water amount of tropospheric delay by the Neill model, adopt the ionosphere independent combination to isolate the two poor blur leveles of L1 carrier wave, then determine L2 carrier wave pair poor blur leveles; Carry out at last the verifying correctness of Carrier Phase Ambiguity Resolution.

Specifically can be according to the following steps:

(1) each reference station continuous acquisition observation data, and be real-time transmitted to central server, correspondence is added in the base station at each bar baseline two ends, has namely inputted L1, L2 carrier phase observation data, P1, the information such as P2 pseudo range observed quantity.

(2) wide lane integer ambiguity fixes fast.Utilize the double frequency phase observed reading can effectively eliminate ionospheric impact, and by differential technique can cancellation receiver clock correction, the impact of satellite clock correction, weaken to a great extent the impact (shorter baseline even can ignore) of track deviation and atmosphere delay deviation simultaneously.Two kinds of methods of fixing main employing of wide lane integer ambiguity: a kind of is wide lane combination definition solving method, and namely according to the definition direct solution of wide lane combination observation value, calculation result mainly is subjected to the impact of atmosphere errors, is applicable to base length 30～50km; Another kind is dual-frequency P code and phase observations value LINEAR COMBINATION METHOD, and calculation result mainly is subjected to the impact of pseudorange precision, and being applicable to base length is 50～100km.Base length was selected calculation method during the present invention can use according to engineering, with fast fixing wide lane integer ambiguity.

1) wide lane combination definition solving method

According to the definition of the wide lane of double frequency combination observation value, can be expressed as wide lane ambiguity:

In the formula,

Be two poor operators; N _wBe wide lane ambiguity;

With

Be respectively L ₁, L ₂The wave band carrier phase observation data; f ₁, f ₂Be L ₁, L ₂The frequency of wave band; λ _w=c/ (f ₁-f ₂) be the wavelength of wide lane observed reading; ρ, O, T, I, M, ε are respectively and defend distance, orbit error, tropospheric delay, ionosphere delay, multipath effect and observation noise.

In CORS (CORS) network, satellite orbital error and Multi-Path Effects can be ignored, and defending distance can accurate Calculation obtain, so in following formula, Affected by ionosphere and tropospheric two poor residual error.Because two poor tropospheres mainly are subjected to the impact of base length and elevation of satellite size, namely increase along with the increase of base length, reduce with the increase of elevation of satellite, particularly the two poor tropospheric delay of low clearance cornerdown star sharply increase.Therefore, when base length within the specific limits, by setting 10～20 ° of satellite cut-off elevation angles, consider again wide lane wavelength X _w=86.2cm, ionosphere and tropospheric two poor residual error can be controlled within the half cycle the impact of wide lane ambiguity, utilize this method can determine single epoch

Value.

2) dual-frequency P code and phase observations value LINEAR COMBINATION METHOD

Because the GPS receiver that dual-frequency code is relevant not only can obtain carrier phase observation data, and can also obtain L1, the P code pseudorange on the L2 frequency, so can adopt the LINEAR COMBINATION METHOD of dual-frequency P code and phase observations value to find the solution wide lane ambiguity:

P in the formula ₁, P ₂Be respectively L ₁, L ₂Wave band P code pseudorange value.Can find out that following formula has been eliminated the ionospheric convection layer and defended the distance impact for how much, ignores multipath effect, following formula only is subjected to the impact of remaining two poor observation noises.Although the impact of pseudorange noise ratio carrier phase is much bigger, because the long wave characteristic of wide lane combination, the pseudorange noise is effectively suppressed.

Because the impact of pseudorange noise only utilizes list observed reading epoch to be difficult to correctly fixedly go out wide lane ambiguity according to following formula

In reference station network, sampling interval is very short, and in order to fix exactly wide lane ambiguity, the present invention is according to the accidental error characteristic of noise, and comprehensive many epoch, observation data was found the solution.

(3) the two poor ambiguity resolution of L1, L2.After the wide lane ambiguity of two differences is determined, utilize the linear combination irrelevant with ionosphere, adopt simultaneously the Neill model to estimate the dried hygroscopic water amount of tropospheric delay, by 1 pair of poor integer ambiguity of the quick fixed L of the recursive least square adjustment of condition equation, then determine the two poor integer ambiguities of L2.And take full advantage of the topological relation of GNSS network differential positioning system base station net, check the accuracy of the two poor integer ambiguity solutions of L1, L2, thereby improve the success ratio of two poor ambiguity resolution.

Adopt ionosphere independent linearity combination to determine

Namely

$=\frac{1}{{\mathrm{\&lambda;}}_w}(\mathrm{\&Delta;}\&dtri;\mathrm{\&rho;}+\mathrm{\&Delta;}\&dtri;O+\mathrm{\&Delta;}\&dtri;T)+\frac{f_2}{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HSA00000022077200031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1+f_2}{\mathrm{\&Delta;}\&dtri;N}_1-\frac{f_2}{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HSA00000022077200031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1+f_2}\mathrm{\&Delta;}\&dtri;N_2$

In the formula,

Be two poor operators;

For without ionosphere delay combination observation value, ρ is station star distance, and O is orbit error, and T is tropospheric delay, takes narrow lane observed reading wavelength X into account _n=c/ (f ₁+ f ₂) and according to wide lane ambiguity definition ${\mathrm{\&Delta;}\&dtri;N}_2={\mathrm{\&Delta;}\&dtri;N}_1-{\mathrm{\&Delta;}\&dtri;N}_w,$ Have

Because in reference station network, satellite orbital error and Multi-Path Effects can be ignored, defending distance can accurate Calculation obtain,

After accurately obtaining, determine in the following formula The major effect source from tropospheric two poor residual errors.Because of tropospheric impact and satellite altitude angular dependence (-dance), introduce mapping function for this reason, it is expressed as zenith delay and about the product of the mapping function of elevation of satellite, so can be with the two poor blur leveles of L1 carrier wave

As solve for parameter, zenith tropospheric delay ZD can obtain its initial value by the Neill model, is calculated as follows

$\left[\begin{array}{ccccc}\&dtri;\mathrm{MF}\left({\mathrm{\&theta;}}_p^1\right)& -\&dtri;\mathrm{MF}\left({\mathrm{\&theta;}}_q^1\right)& {\mathrm{\&lambda;}}_n& ...& 0\\ \&dtri;\mathrm{MF}\left({\mathrm{\&theta;}}_p^2\right)& -\&dtri;\mathrm{MF}\left({\mathrm{\&theta;}}_q^2\right)& 0& {\mathrm{\&lambda;}}_n& ...\\ .& .& .& .& .\\ .& .& .& .& .\\ .& .& .& .& .\\ \&dtri;\mathrm{MF}\left({\mathrm{\&theta;}}_p^k\right)& -\&dtri;\left({\mathrm{\&theta;}}_q^k\right)& 0& ...& {\mathrm{\&lambda;}}_n\end{array}\right]\&times;\left[\begin{array}{c}{\mathrm{ZD}}_p\\ {\mathrm{ZD}}_q\\ {{\mathrm{\&Delta;}\&dtri;\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="HSA00000022077200031.png"\; state="\{\{state\}\}">N</figure-callout>}}_1}^1\\ {{\mathrm{\&Delta;}\&dtri;\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="HSA00000022077200031.png"\; state="\{\{state\}\}">N</figure-callout>}}_1}^2\\ .\\ .\\ .\\ {{\mathrm{\&Delta;}\&dtri;N}_1}^k\end{array}\right]$

In the formula, MF () is the troposphere mapping function; λ _n, λ _wIt is respectively the wavelength of narrow lane and wide lane observation;

For making up without ionosphere;

Be wide lane ambiguity; f ₁, f ₂Frequency for L1 and L2;

Two poor distances of defending; P, q are the reference station numbering; K+1 is the observation satellite number.

For resolving of following formula, the present invention adopts sequential adjustment to carry out the two poor blur leveles of L1 carrier wave

Resolve the sequential adjustment calculation method.

Be located at t _kHave m+1 satellite epoch, and n is arranged _k* 1 observation vector L _k, corresponding covariance matrix is Q _k, weight matrix is

At t _K-1Obtain the model parameter vector estimated value epoch

Corresponding covariance matrix is Q _K-1, error equation is:

$V_k=A_k{\hat{X}}_k-L_k$

In the formula:

Be n _k* (m+2) design matrix;

Be n _k* 1 observing matrix;

${\hat{X}}_k={\left[\begin{array}{cccc}{\mathrm{ZD}}_p& {\mathrm{ZD}}_q& {\mathrm{\&Delta;}\&dtri;\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="HSA00000022077200031.png"\; state="\{\{state\}\}">N</figure-callout>}}_1& ...\end{array}\right]}^T$ Be (m+2) * 1 state estimation vector;

It is as follows to resolve process:

$\left\{\begin{array}{c}{P}_{{\hat{X}}_k}=A_k^T{P}_k{A}_k+P_{\widehat{X_{k-1}}}\\ P_{L_k}=A_k^T{P}_k{L}_k+P_{L_{k-1}}\\ {\hat{X}}_k=P_{{\hat{X}}_k}^{-1}{P}_{L_k}=P_{{\hat{X}}_k}^{-1}(A_k^T{P}_k{L}_k+P_{\widehat{X_{k-1}}}\widehat{X_{k-1}})\end{array}\right.$

Initial value is $P_{{\hat{X}}_1}=A_1^T{P}_1{A}_1,$ ${\mathrm{<figure-callout\; id="1"\; label="P\; L"\; filenames="HSA00000022077200031.png"\; state="\{\{state\}\}">P</figure-callout>}}_{L_{}}=A_1^T{P}_1{\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000022077200031.png"\; state="\{\{state\}\}">L</figure-callout>}}_1;$

By above-mentioned sequential adjustment method, can determine the two poor blur leveles of L1

The two poor blur leveles of L2: ${\mathrm{\&Delta;}\&dtri;N}_2={\mathrm{\&Delta;}\&dtri;N}_1-{\mathrm{\&Delta;}\&dtri;N}_w;$

(4) network checks of blur level correctness.In view of the characteristics of reference station network, can pass through many baselines of reference station network combinatorial test blur level correctness.Inner constructor algorithm had substantial connection when this kind method of inspection calcaneus rete network differential system software was realized, the present invention adopts the Delaunay triangulation network as reference station.

When adopting the Delaunay triangulation network, with triangle for substantially resolving the unit, article three, baseline is chosen identical reference satellite and is carried out two subtractive combinations, then for three baselines that resolve arbitrarily the unit in the network, all there is following relation (resolving unit Cel_ABC as example take what ABC consisted of) in their corresponding blur level:

${\mathrm{\&Delta;}\&dtri;N}_{\mathrm{AB}}^{\mathrm{ij}}+{\mathrm{\&Delta;}\&dtri;N}_{\mathrm{BC}}^{\mathrm{ij}}+{\mathrm{\&Delta;}\&dtri;N}_{\mathrm{CA}}^{\mathrm{ij}}=0$

Advantage of the present invention and beneficial effect:

(1) the present invention can be used for the realization of the Network RTK of CORS system technology, the integer ambiguity between namely can the real-time resolving reference station, thus prepare for generating dummy observation or correction.

(2) the present invention also is the core algorithm of Baselines software afterwards.

Description of drawings

Fig. 1 is baseline integer ambiguity network calculation method process flow diagram between reference station among the present invention;

Fig. 2 is reference station synoptic diagram among the present invention;

Fig. 3 is experiment reference station synoptic diagram among the present invention;

Fig. 4 is that wide lane combination definition solving method is found the solution wide lane ambiguity and separated as a result figure single epoch among the present invention;

Fig. 5 be among the present invention dual-frequency P code and phase observations value LINEAR COMBINATION METHOD find the solution wide lane ambiguity single epoch of value and many epoch the mean value synoptic diagram;

Fig. 6 adopts the ionosphere independent combination to find the solution the two poor blur level synoptic diagram of L1 among the present invention.

Embodiment

Referring to Fig. 1, among the present invention between reference station baseline integer ambiguity network calculation method mainly undertaken by following flow process:

(1) each reference station continuous acquisition observation data, and be real-time transmitted to central server, correspondence is added in the base station at each bar baseline two ends, has namely inputted to comprise L1 L2 carrier phase observation data, P1, P2 pseudo range observed quantity information;

(2) select following two kinds of methods to resolve according to on-site actual situations and determine wide lane integer ambiguity:

When 1) base length is 30～50km, adopt wide lane combination definition solving method:

When 2) base length is 50～100km, adopt double frequency pseudorange P code P1, P2 and phase observations value linear combination solving method:

(3) the two poor ambiguity resolution of L1, L2

After the wide lane ambiguity of two differences is determined, utilize the linear combination irrelevant with ionosphere, adopt simultaneously the Neill model to estimate the dried hygroscopic water amount of tropospheric delay, by 1 pair of poor blur level of the quick fixed L of the recursive least square adjustment of condition equation, then determine the two poor integer ambiguities of L2;

(4) network checks of the two poor blur level correctness of L1, L2:

When adopting the Delaunay triangulation network, with triangle for substantially resolving the unit, article three, baseline is chosen identical reference satellite and is carried out two subtractive combinations, then for three baselines that resolve arbitrarily the unit in the network, all there is following relation in their corresponding blur level, concern below satisfying that the two poor blur leveles of L1, L2 are correct

${\mathrm{\&Delta;}\&dtri;N}_{\mathrm{AB}}^{\mathrm{ij}}+{\mathrm{\&Delta;}\&dtri;N}_{\mathrm{BC}}^{\mathrm{ij}}+{\mathrm{\&Delta;}\&dtri;N}_{\mathrm{CA}}^{\mathrm{ij}}=0$

If the two poor blur leveles of L1, L2 satisfy following formula, then the two poor blur level search of L1, L2 finish, and resolve end; Otherwise, from (1), namely from resolving the two poor blur leveles in wide lane, again resolve.

Referring to Fig. 2, be reference station, wherein alphabetical A-F represents base station, presses the network forming of Delaunay triangulation network network forming principle, sets up the CORS network, determines the triangle at place according to customer location, thereby carries out the network checks of the two poor blur level correctness of L1, L2.

The below uses Jiangsu CORS data as example.Experimental data is the observation data of three stations 30min on the 6th in (station, Jurong (BTJR), station, Yangzhou (BFYZ), Yang Zhongzhan (BTZF)) March in 2007 in the CORS of Jiangsu, Fig. 3 is three station topological relation figure, baseline BTJR-BFYZ (length 53353.895m) wherein, baseline BFYZ-BTZF (length 43668.153m), baseline BTZF-BTJR (length 70022.556m).The method that employing the present invention proposes is resolved the poor blur level of its pair, and end product and the calculation result that adopts high precision Bernese to resolve software are compared.

The first step: fixing fast of wide lane ambiguity, adopt respectively wide lane combination definition solving method and dual-frequency P code and two kinds of methods of phase observations value LINEAR COMBINATION METHOD to find the solution wide lane ambiguity, take the firm PRN2 satellite that rises of baseline as example result such as Fig. 4, shown in Figure 5.

Can find out that from Fig. 4, Fig. 5 it is larger that wide lane combination definition solving method is separated error single epoch when elevation of satellite is very little, along with the change of elevation of satellite is large, calculation result is gradually near the correct round values of wide lane ambiguity.And single epoch of the solution of combination observation value all epoch all fluctuates in next all left and right sides scope on correct round values in dual-frequency P code and the phase observations value LINEAR COMBINATION METHOD, variation with elevation of satellite is irrelevant, namely adopt list solution epoch can't fix wide lane ambiguity value, but after the method for totally averaging many epoch, wide lane ambiguity levels off to round values fast along with increasing of epoch, and wide lane ambiguity is fixed.

The present invention finds to adopt wide lane combination definition solving method in that base length is suitable during less than 50km through mass data test; In base length greater than 50km appropriate to the occasion employing dual-frequency P code and phase observations value LINEAR COMBINATION METHOD.

Determining of the two poor blur leveles of second step: L1.The two poor blur leveles of L1 carrier wave restrain situations for convenience of explanation, and the blur level convergence situation of choosing No. 11 satellites of PRN shows that No. 28 satellites of PRN are as the reference satellite; According to the Bernese calculation result, G28-G11CA 00:00:00...01:45:00 float=14.879 fixed=15.000 sigma=0.121num=421, then the two poor blur leveles of the L1 carrier wave of PRN 11 are 15.Calculation result as shown in Figure 6.

As can be seen from Figure 6, when value that inferior little variance and minimum variance ratio＞F distributes, the two poor blur leveles of No. 11 satellites of PRN are fixed, and the set time, the result was consistent with the Bernese calculation result about 180s, satisfied the requirement of CORS System Dependent fully.

The 3rd step: the network checks of blur level correctness.The present invention carries out the ambiguity resolution of aforesaid way to three baselines shown in Fig. 3, and take No. 11 satellites of PRN as example, the two poor blur leveles of L1 are as follows:

Baseline BTJR-BFYZ:15

Baseline BFYZ-BTZF:8

Baseline BTZF-BTJR:-23

Satisfy ${\mathrm{\&Delta;}\&dtri;N}_{\mathrm{AB}}^{\mathrm{ij}}+{\mathrm{\&Delta;}\&dtri;N}_{\mathrm{BC}}^{\mathrm{ij}}+{\mathrm{\&Delta;}\&dtri;N}_{\mathrm{CA}}^{\mathrm{ij}}=0$ This test condition.

Claims (1)

1. integer ambiguity network fixing means between the CORS system station, it is characterized in that: at first utilize the linear combination of carrier wave and pseudorange to find the solution wide lane ambiguity floating-point solution, long wave characteristic according to wide lane ambiguity, determine wide lane ambiguity integer solution by finding the solution mean value many epoch, i.e. wide lane integer ambiguity; Then estimate the dried hygroscopic water amount of tropospheric delay by the Neill model, adopt the ionosphere independent combination to isolate the two poor blur leveles of L1 carrier wave, then determine L2 carrier wave pair poor blur leveles; Carry out at last the verifying correctness of Carrier Phase Ambiguity Resolution;

Specifically according to the following steps:

(1) each reference station continuous acquisition observation data, and be real-time transmitted to central server, correspondence is added in the base station at each bar baseline two ends, has namely inputted to comprise L1 L2 carrier phase observation data, P1, P2 pseudo range observed quantity information;

(2) select following two kinds of methods to resolve according to on-site actual situations and determine wide lane integer ambiguity:

When 1) base length is 30～50km, adopt wide lane combination definition solving method:

Definition according to the wide lane of double frequency combination observation value is expressed as wide lane ambiguity:

In the formula,

Be two poor operators; N _wBe wide lane ambiguity;

With

Be respectively L ₁, L ₂The wave band carrier phase observation data; f ₁, f ₂Be L ₁, L ₂The frequency of wave band; λ _w=c/ (f ₁-f ₂) be the wavelength of wide lane observed reading; ρ, O, T, I, M, ε are respectively and defend distance, orbit error, tropospheric delay, ionosphere delay, multipath effect and observation noise;

In CORS CORS network, satellite orbital error and Multi-Path Effects are ignored, and defending distance can accurate Calculation obtain, so in following formula,

Affected by ionosphere and tropospheric two poor residual error, because two poor tropospheres mainly are subjected to the impact of base length and elevation of satellite size, namely increase along with the increase of base length, increase with elevation of satellite reduces, particularly the two poor tropospheric delay of low clearance cornerdown star sharply increase, therefore, when base length within the specific limits, by setting 10～20 ° of satellite cut-off elevation angles, consider again wide lane wavelength X _w=86.2cm, ionosphere and tropospheric two poor residual error can be controlled within the half cycle the impact of wide lane ambiguity, utilize this solving method list namely can determine epoch

Value, i.e. two poor wide lane ambiguities;

When 2) base length is 50～100km, adopt double frequency pseudorange P code P1, P2 and phase observations value linear combination solving method:

Because the GPS receiver that dual-frequency code is relevant not only can obtain carrier phase observation data, and can also obtain L1, the P code pseudorange on the L2 frequency, adopt the LINEAR COMBINATION METHOD of dual-frequency P code and phase observations value to find the solution wide lane ambiguity:

P in the formula ₁, P ₂Be respectively L ₁, L ₂Wave band P code pseudorange value; According to the accidental error characteristic of noise, adopt comprehensive many epoch observation datas to find the solution;

(3) the two poor ambiguity resolution of L1, L2

After the wide lane ambiguity of two differences is determined, utilize the linear combination irrelevant with ionosphere, adopt simultaneously the Neill model to estimate the dried hygroscopic water amount of tropospheric delay, by 1 pair of poor blur level of the quick fixed L of the recursive least square adjustment of condition equation, then determine the two poor integer ambiguities of L2;

Adopt ionosphere independent linearity combination to determine Namely find the solution the two poor blur leveles of L1:

In the formula,

Be two poor operators;

For without ionosphere delay combination observation value, ρ is station star distance, and O is orbit error, and T is tropospheric delay, takes narrow lane observed reading wavelength X into account _n=c/ (f ₁+ f ₂) and according to wide lane ambiguity definition $\mathrm{\&Delta;}\&dtri;N_2=\mathrm{\&Delta;}\&dtri;N_1-\mathrm{\&Delta;}\&dtri;N_w,$ Have

Introduce mapping function, it is expressed as zenith delay and about the product of the mapping function of elevation of satellite, with the two poor blur leveles of L1

As solve for parameter, zenith tropospheric delay ZD can obtain its initial value by the Neill model, is calculated as follows:

In the formula, MF () is the troposphere mapping function; λ _n, λ _wIt is respectively the wavelength of narrow lane and wide lane observation;

For making up without ionosphere;

Be wide lane ambiguity; f ₁, f ₂Frequency for L1 and L2; Two poor distances of defending; P, q are the reference station numbering; K+1 is the observation satellite number;

Adopt sequential adjustment to carry out the two poor blur leveles of L1 carrier wave

Resolve, the sequential adjustment calculation method is as follows:

Be located at t _kHave m+1 satellite epoch, and n is arranged _k* 1 observation vector L _k, corresponding covariance matrix is Q _k, weight matrix is

At t _K-1Obtain the model parameter vector estimated value epoch

Corresponding covariance matrix is Q _K-1, error equation is:

$V_k=A_k{\hat{X}}_k-L_k$

In the formula:

Be n _k* (m+2) design matrix;

Be n _k* 1 observing matrix;

${\hat{X}}_k={\left[\begin{array}{cccc}{\mathrm{ZD}}_p& {\mathrm{ZD}}_q& \mathrm{\&Delta;}\&dtri;N_1& \&CenterDot;\&CenterDot;\&CenterDot;\end{array}\right]}^T$ Be (m+2) * 1 state estimation vector;

It is as follows to resolve process:

$\left\{\begin{array}{c}{P}_{{\hat{X}}_k}=A_k^T{P}_k{A}_k+P_{\widehat{X_{k-1}}}\\ P_{L_k}=A_k^T{P}_k{L}_k+P_{L_{k-1}}\\ {\hat{X}}_k=P_{{\hat{X}}_k}^{-1}{P}_{L_k}=P_{{\hat{X}}_k}^{-1}(A_k^T{P}_k{L}_k+P_{\widehat{X_{k-1}}}\widehat{X_{k-1}})\end{array}\right.$

Initial value is $P_{{\hat{X}}_1}=A_1^T{P}_1{A}_1,$ $P_{L_1}=A_1^T{P}_1{L}_1;$

By above-mentioned sequential adjustment method, namely can determine the two poor blur leveles of L1

The two poor blur leveles of L2: $\mathrm{\&Delta;}\&dtri;N_2=\mathrm{\&Delta;}\&dtri;N_1-\mathrm{\&Delta;}\&dtri;N_w;$

(4) network checks of the two poor blur level correctness of L1, L2:

When adopting the Delaunay triangulation network, with triangle for substantially resolving the unit, article three, baseline is chosen identical reference satellite and is carried out two subtractive combinations, then for three baselines that resolve arbitrarily the unit in the network, all there is following relation in their corresponding blur level, concern below satisfying that the two poor blur leveles of L1, L2 are correct

$\mathrm{\&Delta;}\&dtri;N_{\mathrm{AB}}^{\mathrm{ij}}+\mathrm{\&Delta;}\&dtri;N_{\mathrm{BC}}^{\mathrm{ij}}+\mathrm{\&Delta;}\&dtri;N_{\mathrm{CA}}^{\mathrm{ij}}=0.$

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