Navigation constellation ground orientation method

Abstract

The present invention relates to a method for ground orientation of a navigation constellation, comprising: S100, when a satellite navigation system constellation performs autonomous orbit determination, a ground laser observation station tracks and measures all satellites in the satellite navigation system constellation to generate observation data; S200, based on the autonomous orbit determination result and the observation data of the satellite navigation system constellation, calculating relative coordinate parameters of the ground laser observation station relative to the autonomous space reference of the satellite navigation system constellation; S300, based on the relative coordinate parameters and the absolute position parameters of the ground laser observation station in a ground-fixed coordinate system, calculating coordinate conversion parameters of the autonomous space reference of the satellite navigation system constellation; S400, distributing the coordinate conversion parameters to a user terminal; S500, the user terminal performs positioning calculation based on the coordinate conversion parameters, and corrects the coordinate conversion parameters in real time to the positioning result of the user terminal, thereby obtaining a positioning result with reference to the ground-fixed coordinate system. The present invention can realize error correction for autonomous maintenance of the constellation's space reference, effectively improving positioning accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite navigation and positioning, and in particular to a method for ground orientation of a navigation constellation. Background Art

[0002] The satellite navigation constellation can use inter-satellite measurement data to achieve autonomous maintenance of space reference, autonomously update satellite orbit and clock error parameters, form autonomous navigation messages and broadcast them to users through downlinks, and maintain navigation, positioning and timing services in the event of ground system failures.

[0003] However, from a mathematical point of view, inter-satellite measurements are unpredictable for the orientation parameters of satellite orbits, such as orbital inclination and ascending node longitude. In addition, due to the loss of ground support, the navigation constellation cannot autonomously and timely solve and update high-precision earth orientation parameters.

[0004] Therefore, in the absence of ground system support, the space reference maintained by the navigation constellation relying solely on autonomous orbit determination will drift, the satellite orbit error will increase, and the user positioning accuracy will be reduced. Summary of the Invention

[0005] In view of this, the present invention aims to propose a navigation constellation ground orientation method, which can realize the anchoring and correction of the constellation's autonomous space reference, especially when the ground system support is lost and the satellite navigation system constellation performs autonomous orbit determination, which can effectively improve the positioning accuracy.

[0006] An embodiment of the present invention provides a method for ground orientation of a navigation constellation, the method comprising:

[0007] S100, when the satellite navigation system constellation performs autonomous orbit determination, the ground laser observation station tracks and measures all satellites in the satellite navigation system constellation to generate observation data;

[0008] S200, calculating relative coordinate parameters of the ground laser observation station relative to the autonomous space reference of the satellite navigation system constellation based on the autonomous orbit determination result of the satellite navigation system constellation and the observation data;

[0009] S300, calculating coordinate transformation parameters of the autonomous space reference of the satellite navigation system constellation based on the relative coordinate parameters and the absolute position parameters of the ground laser observation station in the earth-fixed coordinate system;

[0010] S400, distributing the coordinate conversion parameters to a receiving end;

[0011] S500: The receiving end performs positioning calculation according to the coordinate conversion parameters, and corrects the coordinate conversion parameters to the positioning result of the receiving end in real time to obtain a positioning result with reference to the earth-fixed coordinate system.

[0012] In a preferred embodiment of the present invention, step S100 further includes:

[0013] The ground laser observation station tracks and measures the satellite using a satellite laser ranging method to form the observation data.

[0014] In a preferred embodiment of the present invention, in step S100:

[0015] Multiple ground laser observation stations are dispatched to track and measure satellites in the satellite navigation system constellation, and the multiple ground laser observation stations are distributed globally, widely or locally.

[0016] In a preferred embodiment of the present invention, step S200 includes:

[0017] At time t, the ground laser observation station r i For the navigation satellites s in the satellite navigation system constellation j The observation equation is:

[0018]

[0019] in, is the ground laser observation station r i Navigation satellites j Satellite laser ranging observations at time t; The error in ranging caused by the tidal change of the position of the ground laser observation station itself; The error caused by the refraction effect of the ranging light in the atmosphere; The deviation in distance measurement caused by the general relativity effect of light in a gravitational field; Laser navigation satellites j The deviation of the reflection point on the surface from the center of mass; is the systematic deviation of the observation of the ground laser observatory itself; is the ground laser observation station r i Navigation satellites j The approximate distance at time t is:

[0020]

[0021] in, and They are the ground laser observation stations r at time t i and navigation satellites j Position parameters of the autonomous orbit determination result in the autonomous space reference of the satellite navigation system constellation; These are the parameters from the autonomous orbit determination results on board the satellite; is the ground laser observation station ri Relative coordinate parameters relative to the autonomous space reference of the satellite navigation system constellation.

[0022] In a preferred embodiment of the present invention, in step S300:

[0023] The ground data processing center performs a difference operation on the relative coordinate parameters and the absolute position parameters, characterizes the differences between different ground laser observation stations through the Bursa seven-parameter model, and calculates the coordinate conversion parameters through the least squares method.

[0024] In a preferred embodiment of the present invention, in step S300:

[0025] The rotation relationship between the earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation is characterized by the seven parameters of the Bursa transformation:

[0026]

[0027] in, is the ground laser observation station r i The absolute position parameter in the Earth-fixed coordinate system, T x 、T y 、T z are the origin conversion parameters of the Earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation, m is the scale conversion parameter of the Earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation, ω z 、ω y and ω x They are the three rotation angles of the earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation.

[0028] In a preferred embodiment of the present invention, in step S400:

[0029] The ground data processing center distributes the coordinate conversion parameters to the receiving end through the short message communication link of the satellite navigation system constellation.

[0030] In a preferred embodiment of the present invention, in step S500:

[0031] The receiving end tracks and measures the navigation satellite while receiving the coordinate conversion parameters to form pseudo-range phase data, and the receiving end performs single-point positioning solution based on the pseudo-range phase data and the coordinate conversion parameters.

[0032] In a preferred embodiment of the present invention, in step S500:

[0033] The pseudo-range observation equation of any ground laser observation station i and any satellite j is:

[0034]

[0035] Among them, δt r is the receiver clock error, τ is the signal propagation time, δt s is the satellite clock error, ΔD trop is the tropospheric delay, ΔD ion is the ionospheric delay, ΔD rel For relativistic delay, are the antenna phase center deviation correction values of the receiver and satellite, ΔD tide is the change in the distance between the star and the earth caused by the displacement of tidal plates, ΔD mult is the pseudorange multipath effect, ε is the pseudorange noise;

[0036] The observation equation of the deionospheric combination is:

[0037]

[0038]

[0039] in, and They are B1 / B2 dual-frequency ionosphere-free combination and B1 / B3 dual-frequency ionosphere-free combination. and are the pseudorange measurements of the three frequency points B1, B2 and B3 respectively; IFB1, IFB2, IFB3 are the group delay parameters of the receiver B1, B2 and B3 frequency points respectively; TGD1, TGD2, TGD3 are the group delay parameters of the satellite B1, B2 and B3 frequency points respectively; f1, f2, f3 are the frequency values of B1, B2 and B3 frequency points respectively; are the projections of the phase center deviations of the receiver B1, B2 and B3 frequencies at the satellite-to-ground distance, are the projections of the phase center deviations of satellite B1, B2 and B3 frequency points on the satellite-to-ground distance;

[0040] The observation equation is linearized, wherein the three-dimensional position component of the ground laser observation station is corrected (dx, dy, dz), and the station clock error δt r Unknown, for four or more observable satellites, the least squares method is repeatedly iterated to correct the three-dimensional position components (dx, dy, dz) and the station clock correction component δt r Add the initial position coordinates and the initial station clock difference to obtain the final positioning result and station clock difference of the user end.

[0041] In a preferred embodiment of the present invention, in step S500:

[0042] The position parameter of the receiver relative to the autonomous spatial reference of the satellite navigation system constellation is recorded as According to the coordinate transformation parameters, the position relative to the ground-fixed coordinate system is solved for:

[0043]

[0044] Among them, T x 、T y 、T z are the origin conversion parameters of the Earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation, m is the scale conversion parameter of the Earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation, ω z 、ω y and ω x They are the three rotation angles of the earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation.

[0045] According to the solution of the present invention, when the satellite navigation system constellation performs autonomous orbit determination, the observation data measured by satellite laser ranging tracking and ground laser observation stations are used to calculate the coordinate conversion parameters of the autonomous space reference of the satellite navigation system constellation. The coordinate conversion parameters include rotation parameters. The rotation parameters are broadcast to the receiving end, i.e., the user, via a short message communication link unique to the satellite navigation system, thereby achieving the distribution of the satellite navigation system's autonomous space reference rotation parameters. The user corrects the rotation parameters to achieve the anchoring and correction of the constellation's autonomous operation space reference, thereby improving the user's positioning accuracy. The present invention not only achieves the anchoring and correction of the satellite navigation system's autonomous space reference, improving the service capability of the satellite navigation system, but also provides a means for distributing the autonomous space reference rotation parameters. In particular, even if the satellite navigation system loses ground support, it can still ensure high-precision positioning services at the user end. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0047] Figure 1 2 is a flow chart of a navigation constellation ground orientation method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0048] The description of the embodiments in this specification should be combined with the corresponding drawings, which should be considered a complete part of this specification. In the drawings, the shapes and thicknesses of the embodiments may be exaggerated and indicated for simplicity or convenience. Furthermore, the various structural components in the drawings will be described separately. It is worth noting that components not shown in the drawings or not described in words are known to those of ordinary skill in the art.

[0049] The description of the embodiments herein and any references to directions and orientations are for ease of description only and are not to be construed as limiting the scope of the present invention. The following description of the preferred embodiments may involve combinations of features, which may exist independently or in combination. The present invention is not specifically limited to the preferred embodiments. The scope of the present invention is defined by the claims.

[0050] like Figure 1 FIG. 1 is a flow chart of a navigation constellation ground orientation method according to an embodiment of the present invention. The method includes:

[0051] S100, when the satellite navigation system constellation performs autonomous orbit determination, the ground laser observation station tracks and measures all satellites in the satellite navigation system constellation to generate observation data.

[0052] In this embodiment, it specifically includes:

[0053] Navigation satellites within the satellite navigation system constellation use inter-satellite link measurements and communications to autonomously update satellite orbit and clock error parameters, predict the satellite orbit and clock error parameters, and generate broadcast ephemeris through fitting, which is then transmitted back to the ground data processing center via a downlink.

[0054] On the ground system, a distributed network of ground-based laser observation stations (with precise coordinates known) is deployed to track and observe navigation satellites as comprehensively as possible, generating SLR (Satellite Laser Ranging) observation data for real-time transmission to a ground-based data processing center. The number of ground-based laser observation stations should preferably be three or more, and they should be distributed as evenly as possible, with global, wide-area, or localized distribution options available.

[0055] S200 , calculating relative coordinate parameters of the ground laser observation station relative to the autonomous space reference of the satellite navigation system constellation based on the autonomous orbit determination result of the satellite navigation system constellation and the observation data.

[0056] In this embodiment, it specifically includes:

[0057] The ground data processing center calculates the relative coordinate parameters of the ground laser observation station with respect to the autonomous spatial reference of the satellite navigation system constellation. This refers to the use of the autonomous spatial reference of the satellite navigation system constellation as a reference for position calibration in the absence of ground system support. The SLR performs two-way ranging between the ground laser observation station and the navigation satellite, and dividing the distance by 2 gives the satellite-to-ground distance.

[0058] At time t, the ground laser observation station r i For the navigation satellites s in the satellite navigation system constellation j The observation equation is:

[0059]

[0060] is the ground laser observation station r i For the navigation satellite s j The SLR observation at time t is represented by the above equation.

[0061] The error in ranging caused by the tidal changes at the location of the ground laser observation station itself, including solid tide, ocean tide and extreme tide, can generally be modified using the relevant IERS specifications. The model is mature and the error can be controlled within 1 mm.

[0062] The error introduced by atmospheric refraction in ranging light is due to the fact that, in a medium-filled space, light propagates at a group velocity less than the speed of light in a vacuum. This delays the time it takes for the laser light to reach Earth from the satellite. Furthermore, atmospheric refraction causes light to no longer travel in a straight line through air; instead, the optical path follows a curved path. These two effects are collectively referred to as the atmospheric refraction effect in laser ranging, and they increase the measured distance from the satellite to the station. The Marini model is the most widely used formula for atmospheric refraction correction in laser ranging.

[0063] This is the deviation in distance measurement caused by the general relativistic effect of light in a gravitational field. When a gravitational field exists, the coordinate velocity of light is no longer a constant, but a variable that is always less than C. This causes light to travel longer in a gravitational field than in flat space. This difference is caused by the gravitational field and is called gravitational delay. It is not the relativistic effect revealed by Einstein and is denoted as ΔtG. A simple calculation approximates:

[0064]

[0065] Among them, M is the mass of the gravitational field source where the light is located, r and R are the distances from the gravitational source to the light source and the observer, and ρ is the distance between the light source and the observer.

[0066] Laser navigation satellites j The deviation of the reflection point on the surface from the center of mass can be simply calculated based on the satellite attitude control model, where the deviation of the satellite laser reflector relative to the satellite center of mass coordinate system is determined by the satellite factory value.

[0067] It is the systematic deviation of the observation of the ground laser observation station itself, provided by each ground laser observation station.

[0068] is the ground laser observation station r i Navigation satellites j The approximate distance at time t is:

[0069]

[0070] in, and are the ground laser observation stations r at time t i and navigation satellites j Position parameters of the autonomous orbit determination result in the autonomous space reference of the satellite navigation system constellation; These are the parameters from the autonomous orbit determination results on board the satellite; is the ground laser observation station r i Relative coordinate parameters relative to the autonomous space reference of the satellite navigation system constellation.

[0071] Among the above observations, only the ground laser observation station r i Position parameters under the autonomous space reference is an unknown parameter to be estimated, and the other parameters are known or accurately modeled. The least squares method can be used to estimate this parameter

[0072] By cyclically processing the observation data of all available ground laser observation stations, the relative position parameters of all ground laser observation stations under the autonomous space reference can be obtained.

[0073] S300: Calculate coordinate conversion parameters of the autonomous space reference of the satellite navigation system constellation according to the relative coordinate parameters and the absolute position parameters of the ground laser observation station in the earth-fixed coordinate system.

[0074] In this embodiment, it specifically includes:

[0075] The ground data processing center calculates the seven parameters of the Bursa transformation between the autonomous space reference and the Earth-fixed coordinate system (BDCS).

[0076] Assume that the ground laser observation station r i The precise position in the Earth-fixed coordinate system (BDCS) is The seven parameters of the Bursa transformation are used to characterize the rotation relationship between the Earth-fixed coordinate system (BDCS) and the autonomous space reference of the satellite navigation system constellation. The functional relationship is as follows:

[0077]

[0078] Among them, T x 、T y 、T z are the origin conversion parameters between the Earth-fixed coordinate system (BDCS) and the autonomous space reference of the satellite navigation system, m is the scale conversion parameter between the Earth-fixed coordinate system (BDCS) and the autonomous space reference of the satellite navigation system, ω z 、ω y and ω x They are the three rotation angles of the Earth-fixed coordinate system (BDCS) and the autonomous spatial reference of the satellite navigation system.

[0079] Equation (a) is used as the observation equation and the seven parameters of the Bursa transformation are used as the variables to be estimated. When there are three or more ground-based laser observation stations, the seven parameters of the Bursa transformation are estimated using the least squares method constructed using Equation (a).

[0080] S400: Distribute the coordinate conversion parameters to a receiving end.

[0081] In this embodiment, it specifically includes:

[0082] The distribution link is a short message communication link unique to satellite navigation systems. The ground data processing center and authorized users form the users of the satellite navigation system's short message communication link. The ground data processing center compiles the seven calculated Bursa conversion parameters into message information, transmits it via an uplink to the short message service operation center, and then compiles it into an outbound message to the user receiver of the user.

[0083] S500: The receiving end performs positioning calculation according to the coordinate conversion parameters, and corrects the coordinate conversion parameters to the positioning result of the receiving end in real time to obtain a positioning result with reference to the earth-fixed coordinate system.

[0084] In this embodiment, it specifically includes:

[0085] The user receiver completes the tracking of all navigation satellites, forms pseudo-range phase data, and uses the least squares method to estimate the position parameters of the user receiver referenced to the autonomous space reference of the satellite navigation system. The processing process is as follows:

[0086] The pseudo-range observation equation for ground laser observation station i and observation satellite j is:

[0087]

[0088] Among them, δt r is the receiver clock error, τ is the signal propagation time, δt s is the satellite clock error, ΔD trop is the tropospheric delay, ΔD ion is the ionospheric delay, ΔD rel For relativistic delay, are the antenna phase center deviation correction values of the receiver and satellite, ΔD tide is the change in the distance between the star and the earth caused by the displacement of tidal plates, ΔD mult is the pseudorange multipath effect, and ε is the pseudorange noise.

[0089] The observation equation for the B1 and B2 deionospheric combination is:

[0090]

[0091] Similarly, the observation equation for the B1 and B3 deionospheric combination is:

[0092]

[0093] Among them, B1, B2 and B3 represent the downlink navigation signals of three satellite navigation systems. and They are B1 / B2 dual-frequency ionosphere-free combination and B1 / B3 dual-frequency ionosphere-free combination. and are the pseudorange measurements of the three frequency points B1, B2 and B3 respectively; IFB1, IFB2, IFB3 are the group delay parameters of the receiver B1, B2 and B3 frequency points respectively; TGD1, TGD2, TGD3 are the group delay parameters of the satellite B1, B2 and B3 frequency points respectively; f1, f2, f3 are the frequency values of B1, B2 and B3 frequency points respectively; are the projections of the phase center deviations of the receiver B1, B2 and B3 frequencies at the satellite-to-ground distance, They are the projections of the phase center deviations of satellite B1, B2 and B3 frequency points on the satellite-to-ground distance.

[0094] Linearize the above observation equation:

[0095] Correction of the three-dimensional position components of the station (dx, dy, dz), station clock error δt r is an unknown parameter, and the linearized observation equation for the B3 frequency point is:

[0096] v j =a j Xl j

[0097] in,

[0098]

[0099]

[0100] The observation equations for observing three navigation satellites are:

[0101] V=AX-L

[0102] V=[v 1 v 2 v 3 ] T

[0103] A=[(a 1 ) T (a 1 ) T (a 1 ) T ] T

[0104] X=[dx dy dz δt r ] T

[0105] L=[l 1 l 2 l 3 ] T

[0106] From the above formula, we can know that through repeated iterations, the three-dimensional position component correction (dx, dy, dz) and the station clock correction component δt r The user's final positioning result and station clock difference are added together with the initial position coordinates and the initial station clock difference.

[0107] Spatial reference drift correction:

[0108] The position parameters of the user receiver obtained by the solution are referenced to the autonomous space reference of the satellite navigation system constellation The position referenced to the Earth-Fixed Coordinate System (BDCS) is obtained by correcting the seven parameters of the Bursa model.

[0109]

[0110] Among them, T x 、T y 、T z are the origin conversion parameters between the Earth-fixed coordinate system (BDCS) and the autonomous space reference of the satellite navigation system constellation, m is the scale conversion parameter between the Earth-fixed coordinate system (BDCS) and the autonomous space reference of the satellite navigation system constellation, ω z 、ω y and ω x are the three rotation angles between the Earth-Fixed Coordinate System (BDCS) and the autonomous space reference of the satellite navigation system constellation. The above parameters are all in the seven parameters of the Bursa model.

[0111] Therefore, when the satellite navigation system loses ground system support, the user terminal can still obtain its position with reference to the earth-fixed coordinate system through the method of this embodiment, and the positioning accuracy can be ensured.

[0112] In the navigation constellation ground orientation method of an embodiment of the present invention, when a satellite navigation system constellation performs autonomous orbit determination, the coordinate conversion parameters of the autonomous space reference of the satellite navigation system constellation are calculated using observation data measured by satellite laser ranging tracking and ground laser observation stations. The coordinate conversion parameters include rotation parameters, and the rotation parameters are broadcast to users via a short message communication link unique to the satellite navigation system, thereby distributing the rotation parameters of the autonomous space reference of the satellite navigation system. By correcting the rotation parameters, the user can achieve anchoring and correction of the autonomous space reference of the constellation, thereby improving the user's positioning accuracy. The present invention not only realizes the anchoring and correction of the autonomous space reference of the satellite navigation system, improving the service capability of the satellite navigation system, but also provides a means for distributing the autonomous space reference rotation parameters. In particular, even if the satellite navigation system loses ground support, it can still ensure high-precision positioning services at the user end.

[0113] The serial numbers of the above-mentioned steps involved in the method of the present invention do not mean the order of execution of the method. The execution order of each step should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0114] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A navigation constellation ground orientation method, characterized in that: The method comprises: S100, when the satellite navigation system constellation performs autonomous orbit determination, the ground laser observation station tracks and measures all satellites in the satellite navigation system constellation to generate observation data; S200, calculating relative coordinate parameters of the ground laser observation station relative to the autonomous space reference of the satellite navigation system constellation based on the autonomous orbit determination result of the satellite navigation system constellation and the observation data; S300, calculating coordinate transformation parameters of the autonomous space reference of the satellite navigation system constellation based on the relative coordinate parameters and the absolute position parameters of the ground laser observation station in the earth-fixed coordinate system; S400, distributing the coordinate conversion parameters to the user terminal; S500: The user terminal performs positioning calculation according to the coordinate conversion parameters, and corrects the coordinate conversion parameters in real time to the positioning result of the user terminal to obtain a positioning result with reference to an earth-fixed coordinate system; Step S200 includes: At time t, the ground laser observation station r i For the navigation satellites s in the satellite navigation system constellation j The observation equation is: in, is the ground laser observation station r i Navigation satellites j Satellite laser ranging observations at time t; The error in ranging caused by the tidal change of the position of the ground laser observation station itself; The error caused by the refraction effect of the ranging light in the atmosphere; The deviation in distance measurement caused by the general relativity effect of light in a gravitational field; Laser navigation satellites j The deviation of the reflection point on the surface from the center of mass; is the systematic bias of the observations of the ground laser observatory itself; is the ground laser observation station r i Navigation satellites j The approximate distance at time t is: in, and They are the ground laser observation stations r at time t i and navigation satellites j Position parameters of the autonomous orbit determination result in the autonomous space reference of the satellite navigation system constellation; These are the parameters from the onboard autonomous orbit determination results.

2. The navigation constellation ground orientation method according to claim 1, characterized in that: Step S100 also includes: The ground laser observation station tracks and measures the satellite using a satellite laser ranging method to form the observation data.

3. The navigation constellation ground orientation method according to claim 1 or 2, characterized in that: In step S100: Multiple ground laser observation stations are dispatched to track and measure satellites in the satellite navigation system constellation, and the multiple ground laser observation stations are distributed globally, widely or locally.

4. The navigation constellation ground orientation method according to claim 1, characterized in that: In step S300: The ground data processing center performs a difference operation on the relative coordinate parameters and the absolute position parameters, characterizes the differences between different ground laser observation stations through the Bursa seven-parameter model, and calculates the coordinate transformation parameters through the least squares method, wherein the coordinate transformation parameters include rotation parameters.

5. The navigation constellation ground orientation method according to claim 4, characterized in that: In step S300: The rotation relationship between the earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation is characterized by the seven parameters of the Bursa transformation: in, is the ground laser observation station r i The absolute position parameter in the Earth-fixed coordinate system, T x 、T y 、T z are the origin conversion parameters of the Earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation, m is the scale conversion parameter of the Earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation, ω z 、ω y and ω x They are the three rotation angles of the earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation.

6. The navigation constellation ground orientation method according to claim 5, characterized in that: In step S400: The ground data processing center distributes the coordinate conversion parameters to the user terminal through the short message communication link of the satellite navigation system constellation.

7. The navigation constellation ground orientation method according to claim 6, characterized in that: In step S500: The user terminal tracks and measures the navigation satellite to form pseudo-range phase data while receiving the coordinate conversion parameters, and performs single-point positioning solution according to the pseudo-range phase data and the coordinate conversion parameters.

8. The navigation constellation ground orientation method according to claim 7, characterized in that: In step S500: The pseudo-range observation equation of any receiver i and any satellite j is: Among them, δt r is the receiver clock error, τ is the signal propagation time, δt s is the satellite clock error, ΔD trop is the tropospheric delay, ΔD ion is the ionospheric delay, ΔD rel For relativistic delay, are the antenna phase center deviation correction values of the receiver and satellite, ΔD tide is the change in the distance between the star and the earth caused by the displacement of tidal plates, ΔD mult is the pseudorange multipath effect, ε is the pseudorange noise; The observation equation of the deionospheric combination is: in, and They are B1 / B2 dual-frequency ionosphere-free combination and B1 / B3 dual-frequency ionosphere-free combination. and are the pseudorange measurements of the three frequency points B1, B2 and B3 respectively; IFB1, IFB2, IFB3 are the group delay parameters of the receiver B1, B2 and B3 frequency points respectively; TGD1, TGD2, TGD3 are the group delay parameters of the satellite B1, B2 and B3 frequency points respectively; f1, f2, f3 are the frequency values of B1, B2 and B3 frequency points respectively; are the projections of the phase center deviations of the receiver B1, B2 and B3 frequencies at the satellite-to-ground distance, are the projections of the phase center deviations of satellite B1, B2 and B3 frequency points on the satellite-to-ground distance; The observation equation is linearized, wherein the three-dimensional position component of the ground laser observation station is corrected (dx, dy, dz), and the station clock error δt r Unknown, for four or more observable satellites, the least squares method is repeatedly iterated to correct the three-dimensional position components (dx, dy, dz) and the station clock correction component δt r Add the initial position coordinates and the initial station clock difference to obtain the final positioning result and station clock difference of the user end.

9. The navigation constellation ground orientation method according to claim 8, characterized in that: In step S500: The position parameter of the receiver relative to the autonomous spatial reference of the satellite navigation system constellation is recorded as According to the coordinate transformation parameters, the position relative to the ground-fixed coordinate system is solved for: Among them, T x 、T y 、T z are the origin conversion parameters of the Earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation, m is the scale conversion parameter of the Earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation, ω z 、ω y and ω x They are the three rotation angles of the earth-fixed coordinate system and the autonomous space reference of the satellite navigation system constellation.

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