CN104330806B - System level gray correlation scaling method between star based on Ka distance measurement mode - Google Patents

Abstract

The invention provides System level gray correlation scaling method between a kind of star based on Ka distance measurement mode, first carry out the resolving of star ground clock correction, planet ground radio pseudorange error of going forward side by side corrects；Then carrying out the resolving of clock correction between star, radio pseudorange error between planet of going forward side by side corrects；By clock correction mutual deviation between clock correction between the star ground star that obtains of two-way link and the star that obtained by two-way link between star, device systems between star can be finally given poor.The present invention can demarcate device systems deviation between star, and its RMS is better than 1ns, can improve timing tracking accuracy between star, thus improve independent navigation precision.

Description

System level gray correlation scaling method between star based on Ka distance measurement mode

Technical field

The present invention relates to a kind of method that between star, System level gray correlation is demarcated, belong to field of satellite navigation.

Background technology

The maturation day by day built along with each large satellite navigation system, the compatible interoperation between people's not only attention location system, Turn one's attention to the independent navigation ability of satellite navigation system the most more.Building inter-satellite link is the premise realizing independent navigation Condition, the development to satellite navigation system has landmark meaning.Inter-satellite link is operated in two ripples of UHF and Ka at present Section, the inherent shortcomings such as UHF antenna wave beam semi-cone angle is wider, and traffic rate is low, be easily disturbed the most substantially have fettered GPS technology Flourish, and under Ka pattern, can effectively reduce interference, strengthening link security, GPS III is planned to use Ka distance measurement mode Replace UHF distance measurement mode.Due to the limitation that Ka band beam is narrow, can only realize measuring one to one between star, want to obtain more H_2O maser information, it is necessary to correspondingly increase H_2O maser equipment.When satellite starts independent navigation, inter-satellite link only depends on Perform task by H_2O maser equipment, between on-board equipment, be inevitably present System level gray correlation or relative device time delay, it is necessary to be accurate Really deduct each System level gray correlation or equipment delay just can obtain correct navigational parameter.What foreign scholar delivered is only about between GPS star Document in terms of Time synchronization algorithm, does not also have relevant report for how demarcating device systems deviation between star.Domestic about star Between the research of link be in the junior stage, in the past in the consideration Main Basis document of device systems deviation between star based on UHF The GPS H_2O maser pattern of range finding system, not yet considers for Ka distance measurement mode.The System level gray correlation of Ka distance measurement mode is demarcated becomes many The difficult point of many scholar's research.

Summary of the invention

In order to overcome the deficiencies in the prior art, the present invention provides System level gray correlation between a kind of star based on Ka distance measurement mode to demarcate Method, the method two-way with star ground radio demarcates device systems deviation between star, it is possible to demarcate device systems deviation between star, its RMS is better than 1ns, can improve timing tracking accuracy between star, thus improve independent navigation precision.

The technical solution adopted for the present invention to solve the technical problems comprises the following steps:

Step 1: the resolving of star ground clock correction

Precise clock correction, precise ephemeris and the meteorological data using IGS website to provide, selects two at Continuous Observation arc on the same day Section is no less than halfhour gps satellite A and B, can set up the earth station of satellite-ground link with these two satellites as ground sight Survey station；The earth station C star ground clock correction relative to satellite A

$T_{\mathrm{CA}}=\frac{1}{2}[R_C-R_A]+\frac{1}{2}[{\mathrm{\τ}}_C^T+{\mathrm{\τ}}_A^R-{\mathrm{\τ}}_A^T-{\mathrm{\τ}}_C^R]+\frac{1}{2}[{\mathrm{\τ}}_{\mathrm{CA}}^{\mathrm{tro}}+{\mathrm{\τ}}_{\mathrm{CA}}^{\mathrm{ion}}+{\mathrm{\τ}}_{\mathrm{CA}}^{\mathrm{sag}}+{\mathrm{\τ}}_{\mathrm{CA}}^{\mathrm{geo}}-{\mathrm{\τ}}_{\mathrm{AC}}^{\mathrm{tro}}-{\mathrm{\τ}}_{\mathrm{AC}}^{\mathrm{ion}}-{\mathrm{\τ}}_{\mathrm{AC}}^{\mathrm{sag}}-{\mathrm{\τ}}_{\mathrm{AC}}^{\mathrm{geo}}];$

Wherein,For the transmitting time delay of earth station C,For the transmitting time delay of satellite A,For the reception time delay of earth station C, For the reception time delay of satellite A,For the tropospheric delay of earth station C to satellite A,Ionization for earth station C to satellite A Layer postpones,For the Sagnac effect of earth station C to satellite A,For the space geometry distance of earth station C to satellite A, For the tropospheric delay of satellite A to earth station C,For the ionosphere delay of satellite A to earth station C,For satellite A to ground Stand the Sagnac effect of C,For the space geometry distance of satellite A to earth station C, R_ASignal for satellite A to earth station C passes Defeated time delay, R_CSignal propagation delay time for earth station C to satellite A；

Step 2: star ground radio pseudorange error corrects

Troposphere time delay in step 1 is corrected by Sa Sitamoning model；To ionospheric delay by ionization Layer grid carries out spatial interpolation and temporal interpolation corrects；The ground that Sagnac effect is passed through survey station and satellite is that coordinate enters admittedly Row corrects；Propagated asymmetric error is carried out by the position relationship of the satellite velocities in precise ephemeris and survey station with satellite Correct；

Step 3: the resolving of clock correction between star

Satellite A launches signal, satellite B measurement pseudorange when receiving

${\mathrm{\ρ}}_{\mathrm{AB}}={\mathrm{\ρ}}_{0\mathrm{AB}}+{\mathrm{\δ}}_A\left(t_e\right)-{\mathrm{\δ}}_B\left(t_r\right)+{\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{AB}}+{\mathrm{\δ}}_A^T+{\mathrm{\δ}}_B^R+{\mathrm{\ϵ}}_{\mathrm{AB}};$

Satellite B launches signal, satellite A measurement pseudorange when receiving

${\mathrm{\ρ}}_{\mathrm{BA}}={\mathrm{\ρ}}_{0\mathrm{BA}}+{\mathrm{\δ}}_B\left(t_e\right)-{\mathrm{\δ}}_A\left(t_r\right)+{\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{BA}}+{\mathrm{\δ}}_B^T+{\mathrm{\δ}}_A^R+{\mathrm{\ϵ}}_{\mathrm{BA}};$

Wherein, ρ_0ABThe geometric distance of satellite B, ρ is transmitted signals to for satellite A_0BAThe geometry of satellite A it is transmitted into for satellite B Distance, δ_A(t_r) it is that satellite A is at the signal t time of reception_rClock correction, δ_B(t_e) it is that satellite B is at signal x time t_eClock correction, δ_A (t_e) it is that satellite A is at signal x time t_eClock correction, δ_B(t_r) it is that satellite B is at the signal t time of reception_rClock correction, δ_{rel_BA}、 δ_{rel_AB}For satellite clock periodically relativistic effect,For satellite B receiving terminal time delay,For satellite A transmitting terminal time delay,For Satellite B transmitting terminal time delay,For satellite A receiving terminal time delay, ε_BAAnd ε_ABIt it is random noise.

Obtain clock correction between the star of satellite A, B

${\mathrm{\δ}}_A\left(t_r\right)-{\mathrm{\δ}}_B\left(t_r\right)=\frac{1}{2}[({\mathrm{\ρ}}_{\mathrm{AB}}-{\mathrm{\ρ}}_{\mathrm{BA}})-({\mathrm{\ρ}}_{0\mathrm{AB}}-{\mathrm{\ρ}}_{0\mathrm{BA}})-({\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{AB}}-{\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{BA}})-({\mathrm{\δ}}_A^T+{\mathrm{\δ}}_B^R)+({\mathrm{\δ}}_B^T+{\mathrm{\δ}}_A^R)]+\mathrm{\ϵ};$ ε represents random Noise；

Step 4: by the bi-directional pseudo between satellite A, B away from naturalization to same epoch；

Step 5: between star, radio pseudorange error corrects

Between the star of satellite A, B of obtaining step 3, clock correction uses relativistic effect correction and the asymmetric correction of propagation path,

Relativistic effect correction formula is:

δ_{rel_AB}=-2X_A(t_r)·V_A(t_r)/c,

δ_{rel_BA}=-2X_B(t_r)·V_B(t_r)/c；

Wherein: X_A(t_r) and X_B(t_r) it is respectively satellite A, B at the position of the time of reception, V_A(t_r) and V_B(t_r) respectively defend Star A, B are in the speed of the time of reception；

The asymmetric correction formula of propagation path is:

ρ_0AB=| X_B(t_r)-X_A(t_e) |=| X_B(t_r)-X_A(t_r)|+(X_B(t_r)-X_A(t_r))·V_B(t_r)/c,

ρ_0BA=| X_A(t_r)-X_B(t_e) |=| X_A(t_r)-X_B(t_r)|+(X_A(t_r)-X_B(t_r))·V_A(t_r)/c,

Finally give clock correction between star $\begin{array}{c}{\mathrm{\δ}}_A\left(t_r\right)-{\mathrm{\δ}}_B\left(t_r\right)=\frac{1}{2}[{\mathrm{\ρ}}_{\mathrm{AB}}-{\mathrm{\ρ}}_{\mathrm{BA}}-\frac{X_B\left(t_r\right)-X_A\left(t_r\right)}{C}(V_A\left(t_r\right)+V_B\left(t_r\right))\\ -\frac{2}{C}(X_B\left(t_r\right)\·V_B\left(t_r\right)-X_A\left(t_r\right)\·V_A\left(t_r\right))-({\mathrm{\δ}}_A^T+{\mathrm{\δ}}_B^R)+({\mathrm{\δ}}_B^T+{\mathrm{\δ}}_A^R)]+\mathrm{\ϵ}\end{array};$

Step 6: between star, device systems difference is demarcated

By clock correction mutual deviation between clock correction between star ground A, B star of obtaining of two-way link and A, B star of being obtained by two-way link between star, Device systems between star can be finally given poor.

The invention has the beneficial effects as follows: demarcate owing to step 5 carries out device systems difference between star, it is possible to carrying out the time between star Before synchronizing, this part system difference is deducted, improve timing tracking accuracy between star, thus improve independent navigation precision.The present invention solves The problem lacking time reference between star relative to clock correction, timing tracking accuracy is at nanosecond order.

Accompanying drawing explanation

Fig. 1 is that between star, device systems deviation demarcates schematic diagram；

Fig. 2 is star ground radio two-way Time transfer receiver schematic diagram；

Fig. 3 is two-way Time transfer receiver schematic diagram between star；

Fig. 4 is the method flow diagram of the present invention.

Detailed description of the invention

The present invention is further described with embodiment below in conjunction with the accompanying drawings, and the present invention includes but are not limited to following enforcement Example.

Device systems deviation calibration principle between star: as it is shown in figure 1, known satellite A, B and have the ground of external atomic frequency standard Stand C, can set up two-way link between star (it is considered herein that two stars can set up inter-satellite link under conditions of visual) between AB, AC, Star ground two-way link can be set up between BC.By two stars ground two-way link AC and BC, resolve respectively obtain certain moment earth station C with Star ground clock correction t of satellite A, B_CA, t_CB, if it is considered to earth station's C clock correction is zero, be readily obtained at this moment satellite A, B relative to Clock correction t of earth station C_A, t_B；On the other hand, clock correction t of synchronization satellite A, B is obtained by two-way link AB resolving between star ′_A, t '_B, can obtain device systems deviation between star:

δ_AB=(t_A-t_B)-(t′_A-t′_B)

Between the star actually get, device systems deviation is that combination is poor, expands into:

${\mathrm{\δ}}_{\mathrm{AB}}=\frac{(d_A^T+d_B^R)-(d_B^T+d_A^R)}{2}$

Wherein:Represent the transmitting time delay of satellite A Yu B respectively；Represent the reception of satellite A Yu B respectively Time delay.

The present invention proposes a kind of method that between star based on Ka distance measurement mode, System level gray correlation is demarcated, for Ka range finding system culminant star Between distance-measuring equipment system deviation demarcate difficulty thus affect the problem of independent navigation precision, with the star ground two-way method mark of radio Determine device systems deviation between star, by two stars ground two-way links with set up two-way link between a star at these two inter-satellites and enter Rower is fixed, comprises the following steps:

Step 1:

The module of pseudorange, input between emulation star is write voluntarily on the basis of hi-Fix orbit determination software BERNESE The coordinate file at the Precise Orbit of IGS, precise clock correction, earth rotation parameter (ERP) and IGS station obtains pseudorange between star；

Step 2:

Pseudorange between the star obtained is carried out Correction of Errors and naturalization epoch, clock correction between available star；

Step 3:

Matlab Programming with Pascal Language obtains star ground pseudorange；

Step 4:

Every error source in star ground radio pseudorange is corrected.Troposphere time delay is entered by Sa Sitamoning model Row corrects.Ionospheric delay carries out spatial interpolation by ionospheric grid and temporal interpolation corrects.Sagnac effect is passed through The ground of survey station and satellite is that coordinate corrects admittedly.Propagated asymmetric error is by the satellite velocities in precise ephemeris and survey The position relationship with satellite of standing corrects；Satellite equipment time delay is demarcated on ground before launching, during the equipment of earth station Prolonging and can also demarcate in advance equally, the work of this part can be implemented before star ground radio two-way pumping station, completes every error source Available star ground clock correction after correction；

Step 5:

Between star, clock correction and the star ground mutual after the recovery of clock correction can obtain Deviation of equipments between star.

Specifically, the step of the present invention is as follows:

Step 1: the generation of the star ground two-way pseudorange value of radio

Use precise clock correction, precise ephemeris and meteorological data that IGS website provides；Select two at Continuous Observation arc on the same day The longer gps satellite of section, with certain earth station as surface-based observing station, emulation generate L-band star ground bi-directional pseudo away from.

Star ground radio two-way Time transfer receiver principle: first distance measuring signal is carried out Pseudo Code Spread Spectrum modulation by earth station, then Satellite is transmitted signals to by earth station equipment.Satellite reception, to after ground station signals, processes despreading by correlation technique and solves Commissioning measure ground station signals to satellite transmission the time delay of process, and this delay data is sent to ground by communication link Standing, meanwhile, atomic time signal is launched signal through Pseudo Code Spread Spectrum modulation ground station by satellite, and earth station can also survey Go out satellite-signal to earth station transmit the time delay of process.Obtain two kinds of data are subtracted each other by earth station, remove various time delay shadow Ring, high-precision star ground clock correction can be obtained.

As in figure 2 it is shown, the time delay that satellite S transmits to earth station's a-signal is:

$R_S=T_S-T_A+{\mathrm{\τ}}_A^T+{\mathrm{\τ}}_S^R+{\mathrm{\τ}}_{\mathrm{AS}}^{\mathrm{sag}}+{\mathrm{\τ}}_{\mathrm{AS}}^{\mathrm{tro}}+{\mathrm{\τ}}_{\mathrm{AS}}^{\mathrm{ion}}+{\mathrm{\τ}}_{\mathrm{AS}}^{\mathrm{rel}}+{\mathrm{\τ}}_{\mathrm{AS}}^{\mathrm{geo}}---\left(3\right)$

The time delay that earth station A transmits to satellite S signal is:

$R_A=T_A-T_S+{\mathrm{\τ}}_S^T+{\mathrm{\τ}}_A^R+{\mathrm{\τ}}_{\mathrm{SA}}^{\mathrm{sag}}+{\mathrm{\τ}}_{\mathrm{SA}}^{\mathrm{tro}}+{\mathrm{\τ}}_{\mathrm{SA}}^{\mathrm{ion}}+{\mathrm{\τ}}_{\mathrm{SA}}^{\mathrm{rel}}+{\mathrm{\τ}}_{\mathrm{SA}}^{\mathrm{geo}}---\left(4\right)$

Wherein:

T_A: relative to the clock correction of system time during the clock face of earth station A；

T_S: relative to the clock correction of system time during the clock face of satellite S；

The transmitting time delay of earth station A；

The transmitting time delay of satellite S；

The reception time delay of earth station A；

The reception time delay of satellite S；

Earth station A is to the tropospheric delay of satellite S；

Earth station A is to the ionosphere delay of satellite S；

The Sagnac effect of earth station A to satellite S；

The space geometry distance of earth station A to satellite S；

Satellite S is to the tropospheric delay of earth station A；

Satellite S is to the ionosphere delay of earth station A；

The Sagnac effect of satellite S to earth station A；

The space geometry distance of satellite S to earth station A；

R_S: the signal propagation delay time of satellite S to earth station A；

R_A: the signal propagation delay time of earth station A to satellite S.

(3), (4) two formulas are subtracted each other the star ground clock correction formula obtaining earth station A relative to satellite clock S:

$\begin{array}{c}{T}_{\mathrm{AS}}=T_A-T_S=\frac{1}{2}[R_A-R_S]+\frac{1}{2}[{\mathrm{\τ}}_A^T+{\mathrm{\τ}}_S^R-{\mathrm{\τ}}_S^T-{\mathrm{\τ}}_A^R]+\frac{1}{2}[{\mathrm{\τ}}_{\mathrm{AS}}^{\mathrm{tro}}+{\mathrm{\τ}}_{\mathrm{AS}}^{\mathrm{ion}}+{\mathrm{\τ}}_{\mathrm{AS}}^{\mathrm{sag}}+{\mathrm{\τ}}_{\mathrm{AS}}^{\mathrm{geo}}\\ -{\mathrm{\τ}}_{\mathrm{SA}}^{\mathrm{tro}}-{\mathrm{\τ}}_{\mathrm{SA}}^{\mathrm{ion}}-{\mathrm{\τ}}_{\mathrm{SA}}^{\mathrm{sag}}-{\mathrm{\τ}}_{\mathrm{SA}}^{\mathrm{geo}}]\end{array}---\left(5\right)$

Satellite equipment time delay is demarcated on ground before launching, and the equipment delay of earth station can also be marked equally in advance Fixed, the work of this part can complete before star ground radio two-way pumping station.

Step 2: star ground radio pseudorange error corrects

Every error source in star ground radio pseudorange is corrected.Troposphere time delay is entered by Sa Sitamoning model Row corrects.Ionospheric delay carries out spatial interpolation by ionospheric grid and temporal interpolation corrects.Sagnac effect is passed through The ground of survey station and satellite is that coordinate corrects admittedly.Propagated asymmetric error is by the satellite velocities in precise ephemeris and survey The position relationship with satellite of standing corrects.

Step 3: the generation of the two-way pseudorange value of radio between star

Owing between star, line, away from earth surface, has only to during analogue observation value consider relativistic effect, propagation path not Two error impacts of symmetric effect.Equipment delay is slower in satellite transit phase change, it is believed that be a constant.

Star ground radio two-way Time transfer receiver principle: as it is shown on figure 3, inter-satellite link uses for reference the measurement pattern that satellite is two-way, Two satellites mutually send signal and find range, and by exchange measurement data, resolve, obtain relative clock correction, so can disappear Except the most of systematic error and the correlation error that affect H_2O maser.The backwardness of satellite borne equipment Development Level causes two satellites It is difficult to accomplish to receive and dispatch ranging data simultaneously.In order to carry out Time transfer receiver, need bi-directional pseudo away from naturalization to same epoch.

${\mathrm{\ρ}}_{\mathrm{AB}}={\mathrm{\ρ}}_{0\mathrm{AB}}+{\mathrm{\δ}}_A\left(t_e\right)-{\mathrm{\δ}}_B\left(t_r\right)+{\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{AB}}+{\mathrm{\δ}}_A^T+{\mathrm{\δ}}_B^R+{\mathrm{\ϵ}}_{\mathrm{AB}}---\left(6\right)$

${\mathrm{\ρ}}_{\mathrm{BA}}={\mathrm{\ρ}}_{0\mathrm{BA}}+{\mathrm{\δ}}_B\left(t_e\right)-{\mathrm{\δ}}_A\left(t_r\right)+{\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{BA}}+{\mathrm{\δ}}_B^T+{\mathrm{\δ}}_A^R+{\mathrm{\ϵ}}_{\mathrm{BA}}---\left(7\right)$

Wherein:

ρ_AB: satellite A launches measurement pseudorange when signal B receives；

ρ_BA: satellite B launches measurement pseudorange when signal A receives；

ρ_0AB: satellite A launches geometric distance when signal B receives；

ρ_0BA: satellite B launches geometric distance when signal A receives；

t_r: signal time of reception；

t_e: signal x time；

δ_A(t_r): satellite A is at the signal t time of reception_rClock correction；

δ_B(t_e): satellite B is at signal x time t_eClock correction；

δ_A(t_e): satellite A is at signal x time t_eClock correction；

δ_B(t_r): satellite B is at the signal t time of reception_rClock correction；

δ_{rel_BA}、δ_{rel_AB}: satellite clock periodically relativistic effect；

Satellite B receiving terminal time delay；

Satellite A transmitting terminal time delay；

Satellite B transmitting terminal time delay；

Satellite A receiving terminal time delay；

ε_BAAnd ε_ABIt it is random noise.

Degree of stability and the accuracy of spaceborne clock are higher, and signal signal transmission delay between two satellites is less than 0.3 Second, in the extremely short time, the change of satellite clock correction is negligible.

(6), (7) two formulas can be rewritten as:

${\mathrm{\ρ}}_{\mathrm{AB}}={\mathrm{\ρ}}_{0\mathrm{AB}}+{\mathrm{\δ}}_A\left(t_r\right)-{\mathrm{\δ}}_B\left(t_r\right)+{\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{AB}}+{\mathrm{\δ}}_A^T+{\mathrm{\δ}}_B^R+{\mathrm{\ϵ}}_{\mathrm{AB}}---\left(8\right)$

${\mathrm{\ρ}}_{\mathrm{BA}}={\mathrm{\ρ}}_{0\mathrm{BA}}+{\mathrm{\δ}}_B\left(t_r\right)-{\mathrm{\δ}}_A\left(t_r\right)+{\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{BA}}+{\mathrm{\δ}}_B^T+{\mathrm{\δ}}_A^R+{\mathrm{\ϵ}}_{\mathrm{BA}}---9)$

(8), (9) two formulas are subtracted each other and can be obtained

${\mathrm{\ρ}}_{\mathrm{AB}}-{\mathrm{\ρ}}_{\mathrm{BA}}={\mathrm{\ρ}}_{0\mathrm{AB}}-{\mathrm{\ρ}}_{0\mathrm{BA}}+2({\mathrm{\δ}}_A\left(t_r\right)-{\mathrm{\δ}}_B\left(t_r\right))+{\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{AB}}-{\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{BA}}+{\mathrm{\ϵ}}_{\mathrm{AB}}-{\mathrm{\ϵ}}_{\mathrm{BA}}+({\mathrm{\δ}}_A^T+{\mathrm{\δ}}_B^R)-({\mathrm{\δ}}_B^T+{\mathrm{\δ}}_A^R)---\left(10\right)$

(10) formula of arrangement i.e. obtains clock correction formula between the star of A, B:

${\mathrm{\δ}}_A\left(t_r\right)-{\mathrm{\δ}}_B\left(t_r\right)=\frac{1}{2}[({\mathrm{\ρ}}_{\mathrm{AB}}-{\mathrm{\ρ}}_{\mathrm{BA}})-({\mathrm{\ρ}}_{0\mathrm{AB}}-{\mathrm{\ρ}}_{0\mathrm{BA}})-({\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{AB}}-{\mathrm{\δ}}_{\mathrm{rel}\_\mathrm{BA}})-({\mathrm{\δ}}_A^T+{\mathrm{\δ}}_B^R)+({\mathrm{\δ}}_B^T+{\mathrm{\δ}}_A^R)]+\mathrm{\ϵ}---\left(11\right)$

(11) comprising relativistic effect and propagation path asymmetric error in formula, these two systematic errors can use strictly Formula be modified.

Relativistic effect correction formula is:

δ_{rel_AB}=-2X_A(t_r)·V_A(t_r)/c (12)

δ_{rel_BA}=-2X_B(t_r)·V_B(t_r)/c (13)

Wherein:

X_i(t_r): satellite is in the position of the time of reception；

V_i(t_r): satellite is in the speed of the time of reception.

The asymmetric correction formula of propagation path is:

ρ_0AB=| X_B(t_r)-X_A(t_e) |=| X_B(t_r)-X_A(t_r)|+(X_B(t_r)-X_A(t_r))·V_B(t_r)/c (14)

ρ_0BA=| X_A(t_r)-X_B(t_e) |=| X_A(t_r)-X_B(t_r)|+(X_A(t_r)-X_B(t_r))·V_A(t_r)/c (15)

Finally give clock correction formula between star as follows:

$\begin{array}{c}{\mathrm{\δ}}_A\left(t_r\right)-{\mathrm{\δ}}_B\left(t_r\right)=\frac{1}{2}[{\mathrm{\ρ}}_{\mathrm{AB}}-{\mathrm{\ρ}}_{\mathrm{BA}}-\frac{X_B\left(t_r\right)-X_A\left(t_r\right)}{C}(V_A\left(t_r\right)+V_B\left(t_r\right))\\ -\frac{2}{C}(X_B\left(t_r\right)\·V_B\left(t_r\right)-X_A\left(t_r\right)\·V_A\left(t_r\right))-({\mathrm{\δ}}_A^T+{\mathrm{\δ}}_B^R)+({\mathrm{\δ}}_B^T+{\mathrm{\δ}}_A^R)]+\mathrm{\ϵ}\end{array}---\left(16\right)$

Step 4: between star, radio pseudorange error corrects

Relativistic effect is corrected by the satellite position in IGS precise ephemeris and speed.The asymmetric mistake of propagated Difference is corrected by the position relationship of the satellite velocities in precise ephemeris and survey station with satellite.

Step 5: System level gray correlation is demarcated

Being demarcated, by star ground two-way link, the System level gray correlation average that between star, two-way link obtains is 39.8448ns, and its standard deviation is 40.3653ns, the System level gray correlation error finally calibrated is less than 1ns.

As shown in Figure 4, embodiments of the invention comprise the following steps:

(1) precise clock correction and the precise ephemeris in the 1 day January in 2011 of IGS website offer are provided；Select and set up star ground chain The gps satellite of road synchronization: 09 and 14, between the Ka distance measurement mode used with GPS III emulation star bi-directional pseudo away from；

(2) precise clock correction, precise ephemeris and the meteorological data in the 1 day January in 2011 of IGS website offer are provided；Select two At the longer gps satellite of Continuous Observation segmental arc on the same day: 09 and 14, with station, Fangshan, Beijing as surface-based observing station, emulation generates L ripple Section star ground bi-directional pseudo away from；

(3) after utilizing Lagrange's interpolation to carry out naturalization epoch star ground radio pseudorange, then Correction of Errors is carried out, bag Include troposphere time delay, ionospheric delay, Sagnac effect and propagated asymmetric error, obtain star ground clock correction；

(4) between star, radio pseudorange error corrects, and including relativistic effect and propagated asymmetric error, obtains between star Clock correction；

(5) with clock correction between star ground clock correction calibration star, System level gray correlation between star is obtained.

Claims (1)

1. System level gray correlation scaling method between a star based on Ka distance measurement mode, it is characterised in that comprise the steps:

Step 1: the resolving of star ground clock correction

Use IGS website provide precise clock correction, precise ephemeris and meteorological data, select two the same day Continuous Observation segmental arc not Less than halfhour gps satellite A and B, so that the earth station C of satellite-ground link can be set up as ground observation with these two satellites Stand；The earth station C star ground clock correction relative to satellite A

Wherein,For the transmitting time delay of earth station C,For the transmitting time delay of satellite A,For the reception time delay of earth station C,For defending The reception time delay of star A,For the tropospheric delay of earth station C to satellite A,For the ionosphere delay of earth station C to satellite A,For the Sagnac effect of earth station C to satellite A,For the space geometry distance of earth station C to satellite A,For satellite A To the tropospheric delay of earth station C,For the ionosphere delay of satellite A to earth station C,For satellite A to earth station C's Sagnac effect,For the space geometry distance of satellite A to earth station C, R_AFor satellite A to earth station C signal transmit time Prolong, R_CSignal propagation delay time for earth station C to satellite A；

Step 2: star ground radio pseudorange error corrects

Troposphere time delay in step 1 is corrected by Sa Sitamoning model；To ionospheric delay by ionosphere net Lattice carry out spatial interpolation and temporal interpolation corrects；The ground that Sagnac effect is passed through survey station and satellite is that coordinate changes admittedly Just；Propagated asymmetric error is changed by the position relationship of the satellite velocities in precise ephemeris and survey station with satellite Just；

Step 3: the resolving of clock correction between star

Satellite A launches signal, satellite B measurement pseudorange when receiving

${\mathrm{\ρ}}_{AB}={\mathrm{\ρ}}_{0AB}+{\mathrm{\δ}}_A\left(t_e\right)-{\mathrm{\δ}}_B\left(t_r\right)+{\mathrm{\δ}}_{rel\_AB}+{\mathrm{\δ}}_A^T+{\mathrm{\δ}}_B^R+{\mathrm{\ϵ}}_{AB};$

Satellite B launches signal, satellite A measurement pseudorange when receiving

${\mathrm{\ρ}}_{BA}={\mathrm{\ρ}}_{0BA}+{\mathrm{\δ}}_B\left(t_e\right)-{\mathrm{\δ}}_A\left(t_r\right)+{\mathrm{\δ}}_{rel\_BA}+{\mathrm{\δ}}_B^T+{\mathrm{\δ}}_A^R+{\mathrm{\ϵ}}_{BA};$

Wherein, ρ_0ABThe geometric distance of satellite B, ρ is transmitted signals to for satellite A_0BAThe geometric distance of satellite A it is transmitted into for satellite B, δ_A(t_r) it is that satellite A is at the signal t time of reception_rClock correction, δ_B(t_e) it is that satellite B is at signal x time t_eClock correction, δ_A(t_e) it is Satellite A is at signal x time t_eClock correction, δ_B(t_r) it is that satellite B is at the signal t time of reception_rClock correction, δ_{rel_BA}、δ_{rel_AB}For Satellite clock periodically relativistic effect,For satellite B receiving terminal time delay,For satellite A transmitting terminal time delay,Launch for satellite B Terminal delay time,For satellite A receiving terminal time delay, ε_BAAnd ε_ABIt it is random noise；

Obtain clock correction between the star of satellite A, B

ε represents random noise；

Step 4: by the bi-directional pseudo between satellite A, B away from naturalization to same epoch；

Step 5: between star, radio pseudorange error corrects

Between the star of satellite A, B of obtaining step 3, clock correction uses relativistic effect correction and the asymmetric correction of propagation path,

Relativistic effect correction formula is:

δ_{rel_AB}=-2X_A(t_r)·V_A(t_r)/c,

δ_{rel_BA}=-2X_B(t_r)·V_B(t_r)/c；

Wherein: X_A(t_r) and X_B(t_r) it is respectively satellite A, B at the position of the time of reception, V_A(t_r) and V_B(t_r) it is respectively satellite A, B Speed in the time of reception；

The asymmetric correction formula of propagation path is:

ρ_0AB=| X_B(t_r)-X_A(t_e) |=| X_B(t_r)-X_A(t_r)|+(X_B(t_r)-X_A(t_r))·V_B(t_r)/c,

ρ_0BA=| X_A(t_r)-X_B(t_e) |=| X_A(t_r)-X_B(t_r)|+(X_A(t_r)-X_B(t_r))·V_A(t_r)/c,

Finally give clock correction between star

Step 6: between star, device systems difference is demarcated

By clock correction mutual deviation between clock correction between star ground A, B star of obtaining of two-way link and A, B star of being obtained by two-way link between star, can be Obtain device systems between star eventually poor.