CN103399334A - Method for improving positioning precision of satellite navigation system on basis of ultra-precise code - Google Patents

Abstract

The invention discloses a method for improving the positioning precision of a satellite navigation system on the basis of an ultra-precise code. The method comprises the following steps of that 1, each navigation satellite in the satellite navigation system broadcasts an ultra-precise code navigation signal, wherein the ultra-precise code navigation signal is a pseudo-random noise code, and a navigation telegraph text and wide area augmentation information are loaded in the navigation signal; 2, a user terminal receives the ultra-precise code navigation signal broadcast by the navigation satellite and demodulates out the navigation telegraph text and the wide area augmentation information; 3, the user terminal obtains the measured pseudo-range from each navigation satellite to the user terminal according to the pseudo-random noise code; and 4, according to the measured pseudo-range, and the modulated navigation telegraph text and the wide area augmentation information, the accurate coordinates of the position of the user terminal are calculated out through iterative decoding. The positioning precision of the user terminal can be well improved and the positioning performance of the satellite navigation system can be obviously improved by the method.

Description

A kind of method that improves Positioning Accuracy of Satellite Navigation System based on the superfinishing code

Technical field

The present invention relates to Technique of Satellite Navigation and Positioning, especially a kind of method that adopts the superfinishing code to improve Positioning Accuracy of Satellite Navigation System, be applicable to the Pseudo-Random Noise Code broadcast navigation signal of Navsat with the superfinishing code, and the satellite navigation system of modulation navigation message and wide area enhancing information.

Background technology

The pseudo-code measuring error of satellite navigation receiver can be estimated with following formula:

${\mathrm{\&sigma;}}_{\mathrm{tDLL}\&ap;}\left\{\begin{array}{cc}{\mathrm{cT}}_c\&CenterDot;\sqrt{\frac{B_n}{2C/N_0}D[1+\frac{2}{\mathrm{TC}/N_0(2-D)}]},& D\&GreaterEqual;\frac{\mathrm{\&pi;}}{B_{\mathrm{fe}}{T}_c}\\ {\mathrm{cT}}_c\&CenterDot;\sqrt{\frac{B_n}{2C/N_0}(\frac{1}{B_{\mathrm{fe}}{T}_c}+\frac{B_{\mathrm{fe}}{T}_c}{\mathrm{\&pi;}-1}{(D-\frac{1}{B_{\mathrm{fe}}{T}_c})}^2)\&times;\frac{2}{\mathrm{TC}/N_0(2-D)}}],& \frac{1}{B_{\mathrm{fe}}{T}_c}<D<\frac{\mathrm{\&pi;}}{B_{\mathrm{fe}}{T}_c}\\ {\mathrm{cT}}_c\&CenterDot;\sqrt{\frac{B_n}{2C/N_0}\left(\frac{1}{B_{\mathrm{fe}}{T}_c}\right)[1+\frac{1}{\mathrm{TC}/N_0}]},& D\&le;\frac{1}{B_{\mathrm{fe}}{T}_c}\end{array}\right.$

In formula, B _nFor loop noise bandwidth; B _FeFor the radio-frequency front-end bandwidth; C is the light velocity in vacuum; T _eChip width for spreading code, meet T _c=1/R _c, R _cFor spreading rate; D is the spacing of lead-lag correlator; C/N ₀For the signal carrier-to-noise ratio; T is integral time.Visible, range error and spreading rate are inversely proportional to.When other conditions are constant, adopt higher spreading rate, namely adopt wider spreading code, can reduce the pseudo-code measuring error.

2002, the Chinese mugwort auspicious academician of state of the Chinese Academy of Sciences heads the list of signers to have invented the satellite navigation system (number of patent application: CN200410046064.1 based on telstar, denomination of invention: transponder satellite communication navigation positioning system, inventor: Ai Guoxiang, execute that waterside is vertical, Wu Haitao, Yan Yihua, Bian Yujing, Hu Yonghui, Li Zhigang, Guo Ji, Cai Xiande, on July 29th, 2009 obtained the authorization).This invention is used the communication frequency on telstar as navigation, having started the full range Communication Development becomes the new beginning that full range navigates.this system adopts to the geostationary orbit telstar of end of lifetime the rail operation of inclining, the east-west direction orbital position that namely only keeps satellite, North and South direction is let alone drift, under the perturbation effect of lunisolar attraction, the telstar drift becomes the inclination geo-synchronous orbit satellite of small inclination, significantly extended the operation on orbit life-span of telstar, utilize the transponder resource on telstar, realize navigation communicating integral (number of patent application: CN200610055909.2, denomination of invention: the method that transforms small inclination synchronized navigation satellite with retired satellite into, inventor: execute waterside vertical, Ai Guoxiang, Chen Jibin, Han Yanben, Geng Jianping, Ma Lihua, on June 3rd, 2009 obtained the authorization).simultaneously, this system aeronautical ground radio station adopt Pseudo-Random Noise Code on three frequencies to every up navigation signal of telstar, telstar forwards and broadcasts this three roads navigation signal, user terminal receives simultaneously three frequency navigation signals and demodulates the orbital position of every telstar, realize three frequency pseudo range measurements and carrier phase measurement, can realize fast, the new system of high-precision navigator fix (number of patent application: CN200910131310.6, patent of invention: the combined method of three frequency code ripple pseudoranges and carrier phase in the satellite navigation location, inventor: Ai Guoxiang, Ma Lihua, execute waterside vertical, Guo Ji, Li Zhigang, Wu Haitao, Bian Yujing, Ma Guanyi, Sun Xiyan, Li Xiaohui, on August 17th, 2011 obtained the authorization).Based on the pseudorange to every Navsat and Doppler shift measurement, can be tied to user terminal on the bottom surface circumference of a circular cone, utilize more than two (the contain two) pseudorange of Navsat and the navigator fix (application number: CN201110164385.1 that the Doppler shift measurement value just realizes user terminal, denomination of invention: in satellite navigation in conjunction with the localization method of Doppler range rate measurement, inventor: Ma Lihua, Ai Guoxiang, Ji Haifu).If every descending a plurality of navigation carrier waves of Navsat while, can effectively reduce the equivalent pseudo range measurement error of this Navsat, improve the navigation and positioning accuracy (application number: CN201110228917.3 of user terminal, denomination of invention: the localization method of multicarrier in satellite navigation, inventor: Ma Lihua, Ai Guoxiang, Ji Haifu).If every carrier number difference that satellite is descending, from physical layer, the positioning precision of utilizing a plurality of carrier frequency point multiplication user terminals having been done to brand-new science sets forth, in order to instruct, in the multi-frequency-point satellite navigation system, utilize the double positioning precision (application number: CN201210090864.8 of user terminal of carrier frequency point resource, denomination of invention: a kind of method of multiplication positioning precision in satellite navigation and location system, inventor: Ai Guoxiang, Ma Lihua, execute waterside vertical, Ji Haifu).

The Navsat of U.S.'s Global Positioning System (GPS) (Global Positioning System, GPS) adopts Pseudo-Random Noise Code broadcast navigation text and the wide area of 1.023Mchips/second bit rate (being called thick code) and 10.23Mchips/second bit rate (being called the essence code) to strengthen information.

Summary of the invention

The purpose of this invention is to provide a kind of method that adopts the superfinishing code to improve Positioning Accuracy of Satellite Navigation System, every Navsat of system adopts the Pseudo-Random Noise Code broadcast navigation text of 40MHz bandwidth and wide area to strengthen information, orbital position and clock that user terminal utilizes navigation message to obtain Navsat correct parameter, utilize enhancing information to correct ionospheric delay and troposphere time delay error, realize the pseudo range measurement of satellite to user terminal.The pseudorange observational error equation that utilization is no less than 4 Navsats builds system of equations, by iterative computation, calculates the accurate coordinate of user terminal location.

In order to achieve the above object, the present invention proposes a kind of method that adopts the superfinishing code to improve Positioning Accuracy of Satellite Navigation System, and it comprises the following steps:

Every Navsat of step 1, satellite navigation system inside is all broadcasted superfinishing code navigation signal, and described superfinishing code navigation signal is Pseudo-Random Noise Code, in navigation signal, is loaded with navigation message and wide area and strengthens information;

Step 2, user terminal receive the described Pseudo-Random Noise Code of all Navsat broadcast, and demodulate navigation message and wide area enhancing information;

Step 3: user terminal obtains the measurement pseudorange of every Navsat to user terminal according to described Pseudo-Random Noise Code;

Step 4, according to described measurement pseudorange, the described navigation message that demodulates and wide area, strengthen information, the accurate coordinate of calculating user terminal location by iterative solution.

In the present invention, adopt superfinishing code broadcast navigation text and the wide area of 20Mchips/second bit rate to strengthen information, high than GPS Pseudo-Random Noise Code digit rate, can effectively improve Positioning Accuracy of Satellite Navigation System, guidance adopts high code speed to improve the positioning precision of user terminal in satellite navigation system signal system designs, and can significantly improve the navigator fix performance of system.

The accompanying drawing explanation

Fig. 1 the present invention is based on the method flow diagram that the superfinishing code improves Positioning Accuracy of Satellite Navigation System.

Embodiment

For making the purpose, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.

Fig. 1 the present invention is based on the method flow diagram that the superfinishing code improves Positioning Accuracy of Satellite Navigation System.As shown in Figure 1, a kind of method based on superfinishing code raising Positioning Accuracy of Satellite Navigation System proposed by the invention specifically comprises the following steps:

Step 1, every Navsat of satellite navigation system inside is all broadcasted superfinishing code navigation signal; Described superfinishing code is the Pseudo-Random Noise Code of 40MHz bandwidth, in navigation signal, is loaded with navigation message and wide area and strengthens information.

Described superfinishing code is Pseudo-Random Noise Code, and every Navsat, corresponding to one group of fixing Pseudo-Random Noise Code, is realized the sign to Navsat; Described user terminal utilizes the auto-correlation of described Pseudo-Random Noise Code and their cross correlation to carry out the transmission time of measure and navigation signal from the satellite to the user terminal, and it is that the light velocity obtains the measurement pseudorange of Navsat to user terminal that this transmission time be multiply by the electric wave transmission speed; The clock that described navigation message comprises system time, Navsat orbital position, Navsat corrects parameter and satellite health situation; Described wide area enhancing information comprises ionosphere delay model parameter, tropospheric delay parameter and integrity information.Wherein, the Navsat number of described satellite navigation system inside is more preferably greater than equaling 4.

Step 2, user terminal receive the described superfinishing code pseudo noise coded signal of all visual navigation satellite broadcastings, and demodulate navigation message and wide area enhancing information;

Described user terminal, can be fixed terminal or mobile terminal, and described fixed terminal, be the fixed satellite receiving equipment; Described mobile terminal is vehicle-mounted, boat-carrying or hand-held receiving equipment.

Step 3, user terminal obtains the measurement pseudorange of every Navsat to user terminal according to described Pseudo-Random Noise Code;

Step 4, according to described measurement pseudorange and the described navigation message that demodulates and wide area enhancing information, the accurate coordinate of calculating user terminal location by iterative solution.

In step 3, described user terminal obtains every visual navigation satellite according to the Pseudo-Random Noise Code of superfinishing code and is specially to the measurement pseudorange of user terminal: according to the transmission time of navigation signal from the Navsat to the user terminal that auto-correlation and the their cross correlation of pseudo-random code noise code measures, multiply by the electric wave transmission speed is that the light velocity obtains described measurement pseudorange.

In addition, measuring t constantly _k, user terminal measurement obtains visual navigation satellite S _jMeasurement pseudorange to user terminal

This is measured pseudorange and meets following pseudorange observation equation:

${\mathrm{\&rho;}}_k^j={[{(X^j-X_k)}^2+{(Y^j-Y_k)}^2+{(Z^j-Z_k)}^2]}^{1/2}$

$+b_k-\mathrm{c\&Delta;}{t}^j+\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_n}^j+\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_P}^j---\left(1\right)$

In formula,

For measuring pseudorange, be known quantity; (X _k, Y _k, Z _k) be that user terminal to be positioned is at t _kAccurate coordinate (amount to be asked) constantly; (X ^j, Y ^j, Z ^j) be Navsat S _jPosition coordinates when the emission navigation signal; b _kEquivalent distances (amount to be asked) for user terminal clock correction; Δ t ^jFor the clock correction parameter of Navsat, can be from the navigation message that Navsat sends, obtaining; C is vacuum light speed,

For ionospheric delay,

For the troposphere time delay, described ionospheric delay and troposphere time delay can obtain according to ionosphere model parameters and tropospheric delay parameter in described wide area enhancing information.

Consider that the observation stochastic error is

The error equation of pseudorange observation is:

${v_k^j=\mathrm{\&rho;}}_k^j-{[{(X^j-X_k)}^2+{(Y^j-Y_k)}^2+{(Z^j-Z_k)}^2]}^{1/2}$

$-b_k+\mathrm{c\&Delta;}{t}^j-\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_n}^j-\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_P}^j---\left(2\right)$

Particularly, in step 4, according to described measurement pseudorange, the described navigation message that demodulates and wide area, strengthen information, by iterative solution, calculate the accurate coordinate of user terminal location, be specially the error equation structure system of equations that the user terminal utilization is no less than the pseudorange observation of 4 Navsats, the accurate coordinate of calculating user terminal location by iterative solution.It further comprises:

Step 4.1, positioning user terminal while resolving, and at first sets the initial value of a user terminal location coordinate, i.e. the general location coordinate (X of user terminal _k ⁰, Y _k ⁰, Z _k ⁰);

Step 4.2, then carry out 1 rank Taylor series expansion to the error equation of the observation of the pseudorange shown in formula (2), obtains containing linearization form user terminal location coordinate modification step-length, described pseudorange observational error equation:

$v_k^j=l_k^j\mathrm{\&delta;}{X}_k+m_k^j\mathrm{\&delta;}{Y}_k+n_k^j\mathrm{\&delta;}{Z}_k$

$-b_k+{\mathrm{\&rho;}}_k^j-{R_k}^j+\mathrm{c\&Delta;}{t}^j-\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_n}^j-\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_P}^j---\left(3\right)$

In formula, δ X _k, δ Y _kWith δ Z _kBe respectively user terminal location coordinate X _k, Y _kAnd Z _kThe correction step-length,

For the general location coordinate of user terminal to Navsat S _jDirection cosine:

$l_k^j=\frac{X^j-{X_k}^i}{{R_k}^j},m_k^j=\frac{Y^j-{Y_k}^i}{{R_k}^j},n_k^j=\frac{Z^j-{Z_k}^i}{{R_k}^j}---\left(4\right)$

R _k ^jFor the general location coordinate of user terminal to Navsat S _jDistance:

R _k ^j＝[(X ^j-X _k ⁱ) ²+(Y ^j-Y _k ⁱ) ²+(Z ^j-Z _k ⁱ) ²] ^1/2 (5)

Wherein, (X _k ⁱ, Y _k ⁱ, Z _k ⁱ) the user terminal general location coordinate that obtains for previous iteration, it is (X during iteration for the first time _k ⁰, Y _k ⁰, Z _k ⁰).

According to the position coordinates of the Navsat of navigation signal x time, utilize the general location coordinate through type (4) of user terminal and general location coordinate that (5) calculate user terminal to nautical star S _jDirection cosine With the general location coordinate of user terminal to Navsat S _jGeometric distance R _k ^j.

Step 4.3, solve the error equation of the linearization pseudorange observation that described step 4.2 obtains, and obtains the correction step-length of user terminal location coordinate;

Described step 4.3 is further comprising the steps:

Step 4.3.1, use the known terms in described linearization pseudorange observational error equation (3)

Expression has:

$v_k^j=l_k^j\mathrm{\&delta;}{X}_k+m_k^j\mathrm{\&delta;}{Y}_k+n_k^j\mathrm{\&delta;}{Z}_k-b_k-L_k^j---\left(6\right)$

In formula,

Constant term for described linearization pseudorange observational error equation:

$L_k^j={R_k}^j-{\mathrm{\&rho;}}_k^j-\mathrm{c\&Delta;}{t}^j+\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_n}^j+\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_P}^j---\left(7\right)$

Step 4.3.2, write formula (6) as matrix form:

V＝AX-L (8)

In formula, X is the undetermined parameter vector:

X＝[δX _k δY _k δZ _k b _k] ^T (9)

A is the matrix of coefficients of undetermined parameter:

$A=\left[\begin{array}{cccc}{l}_k^1& m_k^1& n_k^1& -1\\ l_k^2& m_k^2& n_k^2& -1\\ ...& ...& ...& ...\\ l_k^j& m_k^j& n_k^j& -1\\ ...& ...& ...& ...\\ l_k^M& m_k^M& n_k^M& -1\end{array}\right]---\left(10\right)$

Wherein, visual navigation satellite S _jCorresponding delegation in matrix A.

L is the constant term vector:

$L={\left[\begin{array}{cccccc}{L}_k^1& L_k^2& ...& L_k^j& ...& L_k^M\end{array}\right]}^T---\left(11\right)$

V is the stochastic error vector:

$V={\left[\begin{array}{cccccc}{v}_k^1& v_k^2& ...& v_k^j& ...& v_k^M\end{array}\right]}^T---\left(12\right)$

Step 4.3.3, utilize least square method to solve formula (8), can obtain undetermined parameter vector X:

X＝(A ^TA) ^-1A ^TL (13)

Step 4.4, use the correction step-length of the user terminal location coordinate that described step 5.3 obtains to revise the general location coordinate of user terminal;

The undetermined parameter vector X that formula (13) is calculated brings following formula into, and the general location coordinate of user terminal is revised:

$\left\{\begin{array}{c}{X}_k={X_k}^i+\mathrm{\&delta;}{X}_k\\ Y_k={Y_k}^i+\mathrm{\&delta;}{Y}_k\\ Z_k={Z_k}^i+\mathrm{\&delta;}{Z}_k\end{array}\right.---\left(14\right)$

Step 4.5, general location coordinate repeating step 4.3-step 4.4 using the position coordinates of revised user terminal as user terminal is carried out iterative computation, until meet the iteration termination condition, the position coordinates of the user terminal that obtain this moment is the accurate coordinate of user terminal location.

According to the needs of practical application, described iteration termination condition can require for number of times (such as maximum iterations is 5 times) or accuracy requirement (such as the difference of twice each coordinate figure of iteration in front and back less than a certain fixed value, such as 0.5 meter).

Above-described specific embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the foregoing is only specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of making, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims (9)

1. a method that adopts the superfinishing code to improve Positioning Accuracy of Satellite Navigation System, locate for the high-precision point of user terminal, and it comprises the following steps:

Every Navsat of step 1, satellite navigation system inside is all broadcasted superfinishing code navigation signal, and described superfinishing code navigation signal is Pseudo-Random Noise Code, in navigation signal, is loaded with navigation message and wide area and strengthens information;

Step 2, user terminal receive the described Pseudo-Random Noise Code of all Navsat broadcast, and demodulate navigation message and wide area enhancing information;

Step 3, user terminal obtain the measurement pseudorange of every Navsat to user terminal according to described Pseudo-Random Noise Code;

Step 4, according to described measurement pseudorange, the described navigation message that demodulates and wide area, strengthen information, the accurate coordinate of calculating user terminal location by iterative solution.

2. method according to claim 1, is characterized in that, every Navsat, corresponding to one group of fixing Pseudo-Random Noise Code, is realized the sign to Navsat.

3. method according to claim 1, it is characterized in that, user terminal described in step 3 multiply by electric wave transmission speed according to described superfinishing code navigation signal to the transmission time of user terminal to the measurement pseudorange of Navsat and obtains, and the described transmission time utilizes the auto-correlation of described Pseudo-Random Noise Code and their cross correlation to measure.

4. the described method of any one according to claim 1-3, is characterized in that, described measurement pseudorange meets following pseudorange observation equation:

${\mathrm{\&rho;}}_k^j={[{(X^j-X_k)}^2+{(Y^j-Y_k)}^2+{(Z^j-Z_k)}^2]}^{1/2}$

$+b_k-\mathrm{c\&Delta;}{t}^j+\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_n}^j+\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_P}^j$

Wherein, For measuring t constantly _kUser terminal is to the measurement pseudorange of j Navsat, j=1, and 2 ..., M, M are a number of Navsat; (X _k, Y _k, Z _k) be that user terminal to be positioned is at moment t _kAccurate coordinate; (X ^j, Y ^j, Z ^j) be the position coordinates of described j Navsat when emission superfinishing code navigation signal; b _kEquivalent distances for user terminal clock correction; Δ t ^jClock correction parameter for Navsat; C is vacuum light speed,

For ionospheric delay,

For the troposphere time delay.

5. method according to claim 4, is characterized in that, the clock of described Navsat corrects parameter Δ t ^j, ionospheric delay

With the fluid layer time delay By described superfinishing code navigation signal, obtain.

6. method according to claim 1, is characterized in that, described step 4 further comprises:

Step 4.1, setting user terminal are at moment t _kInitial general location coordinate (X _k ⁰, Y _k ⁰, Z _k ⁰);

Step 4.2, according to described user terminal, to Navsat pseudorange observational error equation, carry out 1 rank Taylor series expansion, obtain the error equation of following linear expression;

$v_k^j=l_k^j\mathrm{\&delta;}{X}_k+m_k^j\mathrm{\&delta;}{Y}_k+n_k^j\mathrm{\&delta;}{Z}_k$

$-b_k+{\mathrm{\&rho;}}_k^j-{R_k}^j+\mathrm{c\&Delta;}{t}^j-\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_n}^j-\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_P}^j$

Wherein, δ X _k, δ Y _kWith δ Z _kBe respectively user terminal location coordinate X _k, Y _kAnd Z _kThe correction step-length,

For the general location coordinate of the user terminal direction cosine to j Navsat, b _kEquivalent distances for user terminal clock correction; Δ t ^jThe clock that is j Navsat corrects parameter; C is vacuum light speed,

Be the ionospheric delay of j Navsat,

Be the troposphere time delay of j Navsat, R _k ^jFor the general location coordinate of the user terminal distance to j Navsat; The following calculating of described direction cosine:

$l_k^j=\frac{X^j-{X_k}^i}{{R_k}^j},m_k^j=\frac{Y^j-{Y_k}^i}{{R_k}^j},n_k^j=\frac{Z^j-{Z_k}^i}{{R_k}^j}$

The following calculating of described distance: R _k ^j=[(X ^j-X _k ⁱ) ²+ (Y ^j-Y _k ⁱ) ²+ (Z ^j-Z _k ⁱ) ²] ^1/2

Wherein, (X _k ⁱ, Y _k ⁱ, Z _k ⁱ) the user terminal general location coordinate that obtains for a front iteration, during iteration, it is initial general location coordinate (X for the first time _k ⁰, Y _k ⁰, Z _k ⁰);

Step 4.3, solve the pseudorange observational error equation of above-mentioned linear expression, obtain the correction step-length of user terminal location coordinate;

Step 4.4, according to described correction step-length, the general location coordinate of user terminal is revised, obtained the general location coordinate of revised user terminal;

If step 4.5 meets the iteration termination condition,, using the general location coordinate of revised user terminal as final user terminal location coordinate output, otherwise go to step 4.3, carry out the next iteration computing.

7. method according to claim 6, is characterized in that, described step 4.3 further comprises:

Known terms in step 4.3.1, pseudorange observational error equation that described linearization is represented is expressed as

Obtain:

$v_k^j=l_k^j\mathrm{\&delta;}{X}_k+m_k^j\mathrm{\&delta;}{Y}_k+n_k^j\mathrm{\&delta;}{Z}_k-b_k-L_k^j;$

Wherein,

For the constant term of described pseudorange observational error equation, following expression:

$L_k^j={R_k}^j-{\mathrm{\&rho;}}_k^j-\mathrm{c\&Delta;}{t}^j+\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_n}^j+\mathrm{\&Delta;}{\mathrm{\&rho;}}_{k_P}^j$

Step 4.3.2, write the pseudorange observational error equation in step 4.3.1 as matrix form, following expression:

V＝AX-L

Wherein, X is the undetermined parameter vector: X=[δ X _kδ Y _kδ Z _kb _k] ^T

A is the matrix of coefficients of undetermined parameter:

$A=\left[\begin{array}{cccc}{l}_k^1& m_k^1& n_k^1& -1\\ l_k^2& m_k^2& n_k^2& -1\\ ...& ...& ...& ...\\ l_k^j& m_k^j& n_k^j& -1\\ ...& ...& ...& ...\\ l_k^M& m_k^M& n_k^M& -1\end{array}\right]$

L is the constant term vector: $L={\left[\begin{array}{cccccc}{L}_k^1& L_k^2& ...& L_k^j& ...& L_k^M\end{array}\right]}^T$

V is the stochastic error vector: $V={\left[\begin{array}{cccccc}{v}_k^1& v_k^2& ...& v_k^j& ...& v_k^M\end{array}\right]}^T$

Wherein, M is a number of Navsat;

Step 4.3.3, utilize least square method to solve the pseudorange observational error equation of described matrix form, obtain undetermined parameter vector X:X=(A ^TA) ^-1A ^TL.

8. method according to claim 1, is characterized in that, described user terminal is fixed terminal or mobile terminal, and described fixed terminal is the fixed satellite receiving equipment, and described mobile terminal is vehicle-mounted, boat-carrying or hand-held receiving equipment.

9. method according to claim 1, is characterized in that, the quantity of described Navsat is at least 4.

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