CN-121410749-B - Navigation satellite orbit determination precision improving method based on pseudo-range deviation correction

CN121410749BCN 121410749 BCN121410749 BCN 121410749BCN-121410749-B

Abstract

The invention relates to a navigation satellite orbit determination precision improving method based on pseudo-range deviation correction, which belongs to the field of satellite navigation, and comprises the steps of combining a ground station double-frequency pseudo-range observation value distributed globally and an external precise orbit clock difference product to construct an ionosphere-free combined observation equation, solving a receiver coordinate through precise single-point positioning and constructing a post-test pseudo-range residual equation; grouping according to the model number of the receiver, applying zero and constraint, aligning the clock difference of the receiver, calculating the double-frequency ionosphere-free combined pseudo-range deviation value of each type of receiver to each navigation satellite through a multi-epoch combined whole network least square batch, selecting the pseudo-range deviation value of the corresponding model according to the model number of the ground station receiver, deducting the pseudo-range deviation value from the double-frequency ionosphere-free combined pseudo-range observed quantity to obtain corrected pseudo-range observed quantity, and jointly calculating the precise orbit parameters of the navigation satellite by utilizing the corrected pseudo-range observed quantity and carrier phase observed quantity. The invention obviously improves the consistency level of the orbit determination precision and the space reference of the navigation satellite.

Inventors

ZHAO LIQIAN
Tang Chengpan
YANG JIANHUA

Assignees

中国科学院上海天文台

Dates

Publication Date: 20260505
Application Date: 20251230

Claims (6)

1. The navigation satellite orbit determination precision improving method based on pseudo-range deviation correction is characterized by comprising the following steps of: S1, carrier phase smoothing is carried out on the globally distributed ground station double-frequency pseudo-range observation values, an ionosphere-free combined observation equation is built by combining an external precise orbit clock difference product, and a receiver coordinate is solved through precise single-point positioning and a post-test pseudo-range residual equation is built; s2, grouping according to the model numbers of the receivers, applying zero and constraint, aligning the clock difference of the receivers, and calculating the double-frequency ionosphere-free combined pseudo-range deviation value of each model number receiver to each navigation satellite through the multi-epoch combined whole network least square batch; S3, selecting a pseudo-range deviation value of a corresponding model according to the model of the ground station receiver, and deducting the pseudo-range deviation value from the double-frequency ionosphere-free combined pseudo-range observed quantity to obtain a corrected pseudo-range observed quantity; S4, jointly calculating precise orbit parameters of the navigation satellite by using the corrected pseudo-range observed quantity and the carrier phase observed quantity; The step S2 comprises the following steps: S201, dividing all the global distributed ground station receivers into different groups according to manufacturers and models, ensuring that the models of the receivers in the same group are completely the same, and counting the total number of the receivers Number of packets Number of receivers in each group , ; S202, applying zero and constraint conditions to each group of receiver models to eliminate rank deficiency problem among pseudo-range deviation parameters; s203, simplifying the post-test pseudo-range residual equation into a linear expression only containing receiver clock error and pseudo-range deviation, and for all The station receiver unifies the serial numbers and establishes the serial numbers of the slave receivers To the model group to which it belongs Providing an index base for the subsequent matrix construction; s204, selecting a1 st receiver as a time reference, constructing clock difference alignment constraint to eliminate reference difference, integrating posttest pseudo-range residual equations of all receivers under all epochs based on the time reference, the receiver model number grouping mapping relation and zero constraint conditions, and assembling an integral network law equation; s205, solving a post-test pseudo-range residual equation by adopting a least square batch processing algorithm, and synchronously estimating all receiver clock error parameters and double-frequency ionosphere-free combined pseudo-range deviation values of each navigation satellite by each type of receiver to realize accurate extraction of deviation parameters; In S202, zero and constraint conditions applied to each group of receiver models are: ; In the formula, Is the first Group all receiver pairs Double-frequency ionosphere-free combined pseudo-range bias values of satellites, zero and constraint conditions prescribe the first Group receiver pair all The sum of the pseudo-range deviation values of the navigation satellites is zero, so that a pseudo-range deviation reference frame is established; in S203, the established linear expression is: ; In the formula, Is the first Group III Station receiver pair satellite A post-test pseudo-range residual; Is the first Group III Receiver clock skew of a station receiver; , Represents the first A group of receivers is provided with a plurality of data channels, Representing the index numbers of the receivers in each group, in group 1 Maximum value of (2) In the first place In a group Maximum value of (2) And so on, in the first In a group Maximum value of (2) ; ; In S204, the whole net law equation is: ; Wherein the observation vector Design matrix for deducting satellite-ground distance, satellite clock error, troposphere delay and residual error after relativistic effect correction The medium parameter characterizes the contribution relationship of receiver clock error and pseudo-range deviation to residual error, and the parameter vector to be solved To include Parameters to be estimated including the clock error of the station receiver and the pseudo-range deviation values of all the ground station receivers with different models to each navigation satellite; Observation vector Is that Dimension vector: ; vector of parameters to be solved Is that Dimension vector: ; Design matrix The number of intermediate lines is: Station receiver Each row corresponds to an observation equation, Design matrix The middle column number is: Clock error of each receiver + Group receiver x Each row of satellites corresponds to one parameter to be estimated; Design matrix Wherein the elements are 0 or 1, including the front part A receiver clock difference portion of the column and a remaining pseudorange bias portion; Receiver clock error part, if a certain line of observed value comes from the first line Station receiver, line I Column coefficient is 1; a pseudo-range deviation part for determining if a certain line of observation value comes from the first line Group receiver and observe satellite as the first The satellite is corresponding to the row The column coefficient of (2) is 1.
2. The method for improving the orbit determination accuracy of a navigation satellite based on the correction of pseudo-range deviation according to claim 1, The S1 comprises the following steps: S101, smoothing original pseudo-range observed values of each globally distributed ground station receiver on a first frequency point F1 and a second frequency point F2 by using carrier phase observed values to reduce pseudo-range measurement noise; S102, utilizing the smoothed double-frequency pseudo-range observation value and carrier phase observation value, combining a navigation satellite precise orbit and a clock error product provided by an IGS analysis center as known information, linearly combining the observation data of two frequency points in an ionosphere-free combination mode, and establishing an ionosphere-free combination observation equation for eliminating the first-order delay influence of an ionosphere; s103, based on an ionosphere-free combined observation equation, carrying out parameter estimation by adopting a precise single-point positioning model, solving the precise three-dimensional coordinates of each ground station receiver, and simultaneously estimating the receiver clock error, zenith troposphere delay and carrier phase ambiguity parameters; S104, recalculating the geometric distance from the satellite to the receiver by using the receiver coordinates and various parameter results obtained by precise single-point positioning calculation, deducting known correction terms including the geometric distance, satellite clock error, troposphere delay and relativistic effects from the ionosphere-free combined pseudo-range observed value, and finally obtaining a post-test pseudo-range residual equation for retaining the receiver clock error and double-frequency ionosphere-free combined pseudo-range deviation information.
3. The method for improving the orbit determination accuracy of a navigation satellite based on the correction of the pseudo-range deviation according to claim 2, In S102, an ionosphere-free combined observation equation for constructing GNSS satellite pseudo-range and carrier phase observation data is: ; ; Wherein, the And The two-frequency pseudo-range and carrier phase ionosphere-free combined observed values of the two frequency points of F1 and F2 are respectively constructed, For the geometric distance of the satellite to the receiver, Is the speed of light in vacuum; And Satellite clock difference and receiver clock difference comprising the receiver and satellite hardware delay after ionosphere-free combination respectively; is a relativistic effect correction term; Is a tropospheric delay; For ionosphere-free combined wavelengths, In order to have no ionospheric combined phase ambiguity, In order to avoid the multipath error after ionosphere combination, For errors including antenna phase center deviation and receiver observation noise after ionosphere-free combination, 、 Carrier frequency values of two frequency points F1 and F2; Correction for phase wrapping effects.
4. The method for improving the orbit determination accuracy of a navigation satellite based on the correction of pseudo-range deviation according to claim 3, In S104, the post-test pseudo-range residual equation is: ; Wherein, the To subtract the geometric distance of the satellite from the receiver Clock error of satellite Tropospheric delay Relativistic effect correction term A post pseudo-range residual portion; In order for the receiver to be clocked out, For receivers For satellites Is a dual-frequency ionosphere-free combined pseudorange bias value.
5. The method for improving the orbit determination accuracy of a navigation satellite based on the correction of pseudo-range deviation according to claim 1, In the S3, for the first Group receiver For navigation satellite The double-frequency ionosphere-free combined pseudo-range observed quantity after the pseudo-range deviation is corrected is as follows: ; Wherein, the For ground station receivers For navigation satellite Is free of ionospheric raw pseudorange observations, Is that Group corresponding type receiver pair navigation satellite Is a function of the pseudorange bias values of (a), And combining the pseudo-range observation values for the double-frequency ionosphere-free combination after the pseudo-range deviation is corrected.
6. The method for improving the orbit determination accuracy of a navigation satellite based on the correction of pseudo-range deviation according to claim 5, The step S4 comprises the following steps: S401, acquiring double-frequency ionosphere-free combined pseudo-range observed quantity and carrier phase observed quantity after pseudo-range deviation correction by using a globally distributed ground station receiver; S402, fixing the coordinates of each measuring station to be accurate known values, and adopting a least square batch processing algorithm to jointly calculate initial satellite positions and speeds, solar pressure parameters, satellite and measuring station receiver clock error parameters, zenith troposphere delay and carrier phase ambiguity parameters as parameters to be estimated; s403, correcting the influence of the pseudo-range deviation according to the resolving result, and realizing the precise orbit determination of the navigation satellite.

Description

Navigation satellite orbit determination precision improving method based on pseudo-range deviation correction Technical Field The invention relates to the fields of satellite navigation, space measurement and control, in particular to a navigation satellite orbit determination precision improving method based on pseudo-range deviation correction. Background The satellite navigation system is used as a key space-time infrastructure of the country, and the provided precise orbit and clock error products are core preconditions for realizing high-precision positioning, navigation and time service. Currently, the international GNSS service organization (IGS) performs precise orbit determination of navigation satellites through about 500 ground monitoring stations distributed globally, and the receivers equipped by these stations come from different manufacturers, and the models are numerous and the differences of hardware parameters (such as front-end bandwidth, correlator intervals) are significant. Because of the non-ideal characteristics of the payload of the navigation satellite, the downlink navigation signal has waveform distortion with different degrees, and the processing modes of the distorted signals by different types of receivers are different, so that pseudorange measurement constant deviations with different magnitudes and signs, namely pseudorange deviations (Code Bias), are generated by different types of receivers on the same satellite, even the same receiver on different satellites. The characteristic of the deviation is that the pseudo-range deviation of the same receiver to different satellites is different, the pseudo-range deviation of different model receivers to the same satellite is different, and the error cannot be effectively absorbed by satellite clock error or receiver clock error parameters in precise orbit determination processing, so that the error becomes an independent systematic error source. In the dual-frequency ionosphere-free combination process, the pseudo-range deviation is amplified, and the accuracy of the orbit determination observation model is directly affected, so that the orbit parameter calculation error is increased. In the current IGS standard orbit determination strategy, the phase observation value is a main constraint, and the pseudo range is mainly used for initial clock error value and anomaly detection, so that the problem of pseudo range deviation is not systematically solved for a long time. In the prior art, the scheme related to the invention mainly comprises the steps of correcting a rotation error by introducing low-orbit satellite observation data and combining a space reference conversion parameter, wherein the pseudo-range deviation caused by a receiver model difference is not involved, fusing space base and foundation observation data to improve orbit geometric intensity, and not providing a method for calibrating and correcting the pseudo-range deviation, and improving orbit precision by optimizing a double-frequency ambiguity fixing strategy, but neglecting the influence of systematic deviation of the pseudo-range observation value. Therefore, how to realize effective calibration and systematic correction of pseudo-range deviation and improve precise orbit determination precision of navigation satellites under the condition of a global distributed heterogeneous GNSS receiver station network is a technical problem to be solved in the field. Disclosure of Invention In view of the above analysis, the invention aims to disclose a navigation satellite orbit determination precision improving method based on pseudo-range deviation correction, and solve the technical problems. The invention discloses a navigation satellite orbit determination precision improving method based on pseudo-range deviation correction, which comprises the following steps: S1, carrier phase smoothing is carried out on the globally distributed ground station double-frequency pseudo-range observation values, an ionosphere-free combined observation equation is built by combining an external precise orbit clock difference product, and a receiver coordinate is solved through precise single-point positioning and a post-test pseudo-range residual equation is built; s2, grouping according to the model numbers of the receivers, applying zero and constraint, aligning the clock difference of the receivers, and calculating the double-frequency ionosphere-free combined pseudo-range deviation value of each model number receiver to each navigation satellite through the multi-epoch combined whole network least square batch; S3, selecting a pseudo-range deviation value of a corresponding model according to the model of the ground station receiver, and deducting the pseudo-range deviation value from the double-frequency ionosphere-free combined pseudo-range observed quantity to obtain a corrected pseudo-range observed quantity; S4, jointly calculating the precise orbit parameters of the navig