阅读说明：本技术 利用非差改正数的多gnss多路径误差恒星日滤波方法及系统 (Multi-GNSS multi-path error star day filtering method and system using non-difference correction ) 是由 王亚伟 邹璇 唐卫明 冯瑾 李洋洋 于 2020-05-29 设计创作，主要内容包括：本发明提供一种利用非差改正数的多GNSS多路径误差恒星日滤波方法及系统,包括对多站数据单天解算后测站之间模糊度固定时段的双差观测值残差信息进行处理,获取双差残差数据记录,对每个双差残差数据记录进行滤波并按历元分解；计算各GNSS系统不同星座卫星的轨道重复周期提前量,并计算各历元内不同测站上卫星对应的非差改正数,得到最终的法方程,求解各站上卫星对应的非差改正数,利用改正数对后续观测值中多路径效应带来的误差进行改正。本发明提出了一种非差改正数的恒星日滤波方案,相比于双差或单差观测值域的恒星日滤波,无需附加额外约束进行双差至单差的转换,模型的建立更加简单；并支持实现不同系统、不同星座类型的卫星观测值多路径误差改正。(The invention provides a multi-GNSS multi-path error star daily filtering method and a multi-GNSS multi-path error star daily filtering system using non-differential correction, which comprises the steps of processing double-difference observation value residual information of a fixed period of ambiguity between stations after single-day calculation of multi-station data, obtaining double-difference residual data records, filtering each double-difference residual data record and decomposing the double-difference residual data records according to epochs; and calculating the advance of the orbit repetition period of different constellation satellites of each GNSS system, calculating the corresponding non-differential correction numbers of the satellites on different observation stations in each epoch to obtain a final normal equation, solving the corresponding non-differential correction numbers of the satellites on each station, and correcting errors caused by multipath effects in subsequent observation values by using the correction numbers. Compared with the sidereal daily filtering of a double-difference or single-difference observation value domain, the sidereal daily filtering scheme of the non-difference correction number does not need additional constraint to carry out conversion from double differences to single differences, and the model is simpler to establish; and the multi-path error correction of the satellite observation values of different systems and different constellation types is supported.)

1. A multi-GNSS multi-path error star day filtering method using non-difference correction is characterized in that: comprises the following steps of (a) carrying out,

step 1, processing double-difference observation value residual error information of a fixed period of ambiguity between stations after single-day calculation of multi-station data to obtain double-difference residual error data records;

step 2, filtering and decomposing each double-difference residual error data record according to the epoch, comprising the following substeps,

step 2.1, according to the double-difference residual error data records, forming a double-difference residual error sequence of two satellites on two stations within a period of fixed ambiguity, carrying out low-pass filtering on the sequence to eliminate observation noise contained in the sequence and keep a multi-path error with a double-difference relation;

2.2, decomposing, classifying and reprocessing the filtered data records according to observation epochs, wherein each data record is distinguished according to an epoch and comprises a double-difference relation between a survey station and a satellite in the epoch and a filtered double-difference residual error;

step 3, calculating the orbit repetition period lead of different constellation satellites of each GNSS system, and calculating the corresponding non-difference correction numbers of the satellites on different observation stations in each epoch, comprising the following substeps,

3.1, reading related parameters in the broadcast ephemeris, and solving the advance of the orbit repetition period of each satellite by combining with a Kepler third law;

step 3.2, calculating non-differential corrections corresponding to satellites on different stations in each epoch, wherein for a single epoch, a matrix formed by parameters of the non-differential corrections of the satellites on each station is a parameter vector X to be solved, a filtered double-differential residual value s is set as an observed value, a coefficient matrix corresponding to an observation equation is set as b, and finally a parameter vector containing the non-differential corrections corresponding to the satellites on each station to be solved is set as X;

assuming that a double difference record contains stations e and f and satellites i and j, the number of non-difference corrections to be estimated is The corresponding observation equation is

bx＝s

Wherein, b ═ 1-1-11]，

The weight corresponding to the observation equation is p, and the variance D of the double-difference residual value is set₀＝a₀When the unit is meter, the weight is p is 1m/D₀(ii) a A double-difference residual error observed value relates to four non-difference correction numbers, a coefficient matrix b contains four elements corresponding to four elements in X, and after index values of the group of elements in the X are obtained, an n matrix and a w matrix corresponding to a formula calculation equation are utilized:

n＝b^Tpb w＝b^Tps

step 3.3, according to the normal equation obtained in step 3.2, adding an additional constraint condition to the parameter to be estimated, including obtaining an observation equation at the moment for any parameter Z to be estimated, wherein,

b＝1

x＝Z

s＝0

for additional constraints, taking the additional constraints as virtual observation values to participate in calculation, and determining the weight of the constraints; at the moment, one data record constrains one grid point parameter, so the coefficient matrix b only relates to one element, all the data records are gradually traversed, constraints are added to all grid points, and the n and w matrixes corresponding to the normal equation are obtained by using the formula;

step 4, obtaining a final normal equation, solving a non-difference correction number corresponding to the satellite on each station, and correcting errors caused by multipath effects in subsequent observed values by using the correction number, wherein the method comprises the following substeps,

step 4.1, superposing the corresponding N and W arrays obtained in the step 3.2 and the step 3.3 respectively to form a normal equation coefficient array N and a normal equation constant array W, and utilizing the following formula

X＝N^-1W

Solving to obtain X which is used as a non-difference correction number corresponding to the satellite on each station;

step 4.2, when the multipath error is eliminated by using the correction number obtained in the step 4.1, after the relevant information of each satellite of each survey station is obtained, correcting according to the number of the survey station and the satellite;

and 4.3, after the multipath effect of the observed values is corrected by all visible satellites of all stations, the influence of multipath errors is effectively weakened in the subsequent GNSS data processing process.

2. The method of claim 1, wherein the multi-GNSS multi-path error sidereal day filtering using non-difference corrections comprises: step 1 comprises the sub-steps of,

step 1.1, setting an index list according to data containing ambiguity fixing information obtained by resolving, wherein each index record relates to two stations, two satellites and fixed starting and stopping epochs of ambiguity;

and 1.2, after the index records are obtained, processing the resolved residual error information aiming at each index, wherein the residual error information comprises satellite related information participating in resolving on each station, the related information comprises epoch count, residual error, satellite altitude angle and azimuth angle, and obtaining double-difference residual error formed by two co-view satellites on two stations related to each index and forming data records.

3. The method of claim 1, wherein the multi-GNSS multi-path error sidereal day filtering using non-difference corrections comprises: in step 2.1, the double difference residual sequence is low pass filtered using a Savitzky-Golay smoothing filter.

4. The method of claim 1, wherein the multi-GNSS multi-path error sidereal day filtering using non-difference corrections comprises: in step 3.1, comprising the following sub-steps,

step 3.1.1, firstly, acquiring an orbit semimajor axis parameter a and a satellite angular velocity parameter correction quantity parameter delta n from a broadcast ephemeris, and averaging;

step 3.1.2, if the revolution period of the system satellite in the orbit repetition period is k, the satellite orbit repetition period T_sExpressed as such, the expression is,

wherein the content of the first and second substances,the square root of each GNSS system corresponding to a standard gravity parameter is shown, G is a universal gravitation constant, M is the earth mass, and T is the time of one satellite running circle;

step 3.1.3, adding T_sFurther expressed as the advance t of the track repetition period corresponding to the number of days,

t＝d·86400-T_s

and d is an integer day corresponding to the satellite orbit repetition period, and the orbit repetition period lead of each satellite is calculated according to the integer day.

5. The multi-GNSS multi-path error sidereal day filtering method using non-difference corrections according to claim 1 or 2 or 3 or 4, characterized in that: the method supports the realization of multipath error correction of satellite observation values of different systems and different constellation types by using the broadcast ephemeris of the satellite.

6. A multi-GNSS multi-path error star-day filtering system using non-difference correction numbers is characterized in that: for implementing a multi-GNSS multi-path error sidereal day filtering method with non-difference corrections as claimed in claims 1 to 5.

Technical Field

The invention belongs to the field of global satellite navigation systems, and particularly relates to a technology for weakening a multipath effect existing in multi-GNSS precision data processing and improving the precision of a resolving result.

Background

At present, aiming at the influence of the multipath effect on the positioning precision, a modeling or signal processing technology is mainly used for analysis in the data processing process so as to achieve the effect of separating out the multipath error and weaken the influence of the multipath error on the GNSS precision calculation. The sidereal day filtering SF (sidereal filtering) is a multipath error weakening method which is widely applied at present, and the theoretical basis is that when a receiver antenna and the surrounding environment are kept unchanged, the multi-path effect of a station is mainly related to the change of the satellite signal propagation direction, the multi-path error is separated by using the day-of-week repetition characteristic of a satellite constellation, and the observed quantity of the subsequent day is corrected by using the separation, so that the aim of weakening the multipath error is fulfilled^[1][2]. However, with the gradual and deep knowledge of the mechanism of multipath error generation, the learners find that the satellite orbit repetition period is not a simple Sidereal day duration, and there are differences between different satellites, and Choi finds through further research that it is more reasonable to select an average orbit repetition period for filtering solution, and the period has about 9s of lead relative to a Sidereal day, and thus proposes an improved Sidereal day filtering msf (modified Sidereal filtering)^[3]. Larson et al select the time difference of the same satellite reaching the same station center as the orbit repeat period, and propose an improved ARTA (aspect repeat time adjustment) method^[4]. The above methods are all used for sidereal day filtering in the coordinate domain, that is, multipath errors are extracted from the coordinate sequence and used for correcting the subsequent sidereal day positioning result, and the sidereal day filtering method is also applicable to correction in the observation value domain.

Alber provides a method for mapping and converting double-difference observed value residual errors to extract multipath effects when researching water vapor content in atmosphere^[5]. Ragheb compares the method of respectively using the star day filtering based on the coordinate domain and the observation value domain, and considers that the former has the calculation efficiencyHigher, the latter of which can achieve higher improved accuracy^[6]. Aiming at the conclusion of GPS satellite data acquisition, Ye uses a star daily filtering method to perform experiments on BDS to indicate that the orbit repetition periods of different constellation satellites of BDS have differences, and uses the star daily filtering method to perform multi-path error modeling research on BDS, and maps double-difference residuals of observed values into single-difference residuals by adding extra constraint to deal with the situation that reference satellites are changed or lost, and performs star daily filtering of single-difference observation value domains to weaken multi-path errors^[7]. With the development of each GNSS system and each regional augmentation system, the application of multiple systems is a necessary trend of future GNSS technology development, and the multipath effect is one of error sources of GNSS observation.

Reference to the literature

[1]Ding,X.,Chen,Y.,Zhu,J.,&Huang,D.(1999).Surface deformationdetection using gps.Proceedings of International Technical Meeting of theSatellite Division of the Institute of Navigation,53-62.

[2]Seeber,G.,Menge,F.,C.,Wübbena,G.,&Schmitz,M.(1998).PreciseGPS Positioning Improvements by Reducing Antenna and Site DependentEffects.Advances in Positioning and Reference Frames.Springer BerlinHeidelberg.

[3]Choi K,Bilich A,Larson K M,Axelrad P.(2004).Modified siderealfiltering:Implications for high-rate GPS positioning.Geophysical researchletters,31(22).

[4]Larson,K.M.,Bilich,A.,&Axelrad,P.(2007).Improving the precision ofhigh-rate gps.Journal of Geophysical Research Solid Earth,112(B5).

[5]Alber C,Ware R,Rocken C,Braun J.(2000).Obtaining single path phasedelays from GPS double differences.Geophysical Research Letters,27(17),2661-2664.

[6]Ragheb,A.E.,Clarke,P.J.,&Edwards,S.J.(2007).GPS siderealfiltering:coordinate-and carrier-phase-level strategies.Journal of Geodesy,81(5),325-335.

[7]Ye S,Chen D,Liu Y,Jiang P,Tang W,Xia P.(2015).Carrier phasemultipath mitigation for BeiDou navigation satellite system.GPS Solutions,19(4),545-557.

Disclosure of Invention

Aiming at the problem that the precision of GNSS precision data processing in a global navigation satellite system is influenced by a multipath effect, the invention provides a sidereal day filtering scheme based on a non-difference correction number, which can be used for weakening the influence of multipath errors of an observation value range.

In order to solve the technical problems, the invention adopts the following technical scheme:

a multi-GNSS multi-path error sidereal day filtering method using non-difference correction includes the following steps,

step 1, processing double-difference observation value residual error information of a fixed period of ambiguity between stations after single-day calculation of multi-station data to obtain double-difference residual error data records;

step 2, filtering and decomposing each double-difference residual error data record according to the epoch, comprising the following substeps,

step 2.1, according to the double-difference residual error data records, forming a double-difference residual error sequence of two satellites on two stations within a period of fixed ambiguity, carrying out low-pass filtering on the sequence to eliminate observation noise contained in the sequence and keep a multi-path error with a double-difference relation;

2.2, decomposing, classifying and reprocessing the filtered data records according to observation epochs, wherein each data record is distinguished according to an epoch and comprises a double-difference relation between a survey station and a satellite in the epoch and a filtered double-difference residual error;

step 3, calculating the orbit repetition period lead of different constellation satellites of each GNSS system, and calculating the corresponding non-difference correction numbers of the satellites on different observation stations in each epoch, comprising the following substeps,

3.1, reading related parameters in the broadcast ephemeris, and solving the advance of the orbit repetition period of each satellite by combining with a Kepler third law;

step 3.2, calculating non-differential corrections corresponding to satellites on different stations in each epoch, wherein for a single epoch, a matrix formed by parameters of the non-differential corrections of the satellites on each station is a parameter vector X to be solved, a filtered double-differential residual value s is set as an observed value, a coefficient matrix corresponding to an observation equation is set as b, and finally a parameter vector containing the non-differential corrections corresponding to the satellites on each station to be solved is set as X;

assuming that a double difference record contains stations e and f and satellites i and j, the number of non-difference corrections to be estimated is When the corresponding observation equation is bx ═ s

Wherein the content of the first and second substances,

the weight corresponding to the observation equation is p, and the variance D of the double-difference residual value is set₀＝a₀When the unit is meter, the weight is p is 1m/D₀(ii) a A double-difference residual error observed value relates to four non-difference correction numbers, a coefficient matrix b contains four elements corresponding to four elements in X, and after index values of the group of elements in the X are obtained, an n matrix and a w matrix corresponding to a formula calculation equation are utilized:

n＝b^Tpb w＝b^Tps

step 3.3, according to the normal equation obtained in step 3.2, adding an additional constraint condition to the parameter to be estimated, including obtaining an observation equation at the moment for any parameter Z to be estimated, wherein,

b＝1

x＝Z

s＝0

for additional constraints, taking the additional constraints as virtual observation values to participate in calculation, and determining the weight of the constraints; at the moment, one data record constrains one grid point parameter, so the coefficient matrix b only relates to one element, all the data records are gradually traversed, constraints are added to all grid points, and the n and w matrixes corresponding to the normal equation are obtained by using the formula;

step 4, obtaining a final normal equation, solving a non-difference correction number corresponding to the satellite on each station, and correcting errors caused by multipath effects in subsequent observed values by using the correction number, wherein the method comprises the following substeps,

step 4.1, superposing the corresponding N and W arrays obtained in the step 3.2 and the step 3.3 respectively to form a normal equation coefficient array N and a normal equation constant array W, and utilizing the following formula

X＝N^-1W

Solving to obtain X which is used as a non-difference correction number corresponding to the satellite on each station;

step 4.2, when the multipath error is eliminated by using the correction number obtained in the step 4.1, after the relevant information of each satellite of each survey station is obtained, correcting according to the number of the survey station and the satellite;

and 4.3, after the multipath effect of the observed values is corrected by all visible satellites of all stations, the influence of multipath errors is effectively weakened in the subsequent GNSS data processing process.

Furthermore, step 1 comprises the sub-steps of,

step 1.1, setting an index list according to data containing ambiguity fixing information obtained by resolving, wherein each index record relates to two stations, two satellites and fixed starting and stopping epochs of ambiguity;

and 1.2, after the index records are obtained, processing the resolved residual error information aiming at each index, wherein the residual error information comprises satellite related information participating in resolving on each station, the related information comprises epoch count, residual error, satellite altitude angle and azimuth angle, and obtaining double-difference residual error formed by two co-view satellites on two stations related to each index and forming data records.

Furthermore, in step 2.1, the double difference residual sequence is low-pass filtered using a Savitzky-Golay smoothing filter.

Furthermore, step 3.1, comprises the following sub-steps,

step 3.1.1, firstly, acquiring an orbit semimajor axis parameter a and a satellite angular velocity parameter correction quantity parameter delta n from a broadcast ephemeris, and averaging;

step 3.1.2, if the revolution period of the system satellite in the orbit repetition period is k, the satellite orbit repetition period T_sExpressed as such, the expression is,

wherein the content of the first and second substances,the square root of each GNSS system corresponding to a standard gravity parameter is shown, G is a universal gravitation constant, M is the earth mass, and T is the time of one satellite running circle;

step 3.1.3, adding T_sFurther expressed as the advance t of the track repetition period corresponding to the number of days,

t＝d·86400-T_s

and d is an integer day corresponding to the satellite orbit repetition period, and the orbit repetition period lead of each satellite is calculated according to the integer day.

And the multi-path error correction of the satellite observation values of different systems and different constellation types is supported by using the broadcast ephemeris of the satellite.

The invention provides a multi-GNSS multi-path error sidereal day filtering system using a non-difference correction number, which is used for realizing the multi-GNSS multi-path error sidereal day filtering method using the non-difference correction number.

Compared with the prior art, the invention has the beneficial effects that:

1. compared with the sidereal daily filtering of a double-difference or single-difference observation value domain, the sidereal daily filtering scheme of the non-difference correction number provided by the invention does not need additional constraint to carry out conversion from double differences to single differences, and the establishment of the model is simpler.

2. The invention can calculate the orbit repetition period of satellites of different satellite constellations of different GNSS systems and the same system by using the broadcast ephemeris of the satellite, and can realize the multipath error correction of the satellite observation values of different systems and different constellation types by matching with the model file.

3. The invention 'distributes' the multipath error to the survey station satellite participating in resolving through least square estimation during model building, solves the problem of reference satellite variation, and the normalized model file enables the follow-up correction and use to be more convenient.

Drawings

FIG. 1 is a schematic flow chart of an embodiment of the present invention.

Concrete real-time mode

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The invention provides a multi-GNSS multi-path error star daily filtering method using non-difference correction numbers, which effectively utilizes multi-path information contained in double-difference observation value residual errors between stations (step 1), can flexibly set related parameters of a low-pass filter in a data de-noising process, simultaneously accurately calculates the orbit repetition period lead of satellites with different constellation types of each system by using broadcast ephemeris and a Kepler third law, and estimates the non-difference multi-path error correction numbers of each satellite by using least square (step 2, step 3 and step 4.1). When multipath error correction is carried out by using the non-difference correction number subsequently, the realization method is simple and quick (step 4.2 and step 4.3). Referring to fig. 1, a multi-GNSS multi-path error sidereal day filtering method using non-difference corrections provided in the embodiment of the present invention specifically includes the following steps:

step 1, processing double-difference observation value residual error information of ambiguity fixed time intervals between stations after single-day calculation of multi-station data, specifically comprising:

step 1.1, setting an index list according to the data containing the ambiguity fixing information obtained by resolving, wherein each index record relates to two stations, two satellites and a start-stop epoch with fixed ambiguity.

Step 1.2, after the index records are obtained, processing the resolved residual error information aiming at each index, wherein the residual error information comprises satellite related information (specifically comprising epoch count, residual error, satellite altitude angle, azimuth angle and the like) participating in resolving on each station, obtaining double-difference residual errors formed by two co-view satellites on two stations related to each index, and forming data records.

Step 2, filtering and decomposing each double-difference residual error data record according to the epoch, and specifically comprises the following steps:

and 2.1, forming a double-difference residual sequence of data recorded as two satellites on two stations in a period of fixed ambiguity through the step 1.2, and performing low-pass filtering on the sequence by using a Savitzky-Golay smoothing filter to remove observation noise contained in the sequence and keep a multi-path error with double-difference relation.

And 2.2, decomposing, classifying and reprocessing the filtered data records according to the observation epoch, wherein each data record is distinguished according to the epoch and comprises the double-difference relation between the observation station and the satellite in the epoch and the filtered double-difference residual error.

Step 3, calculating the orbit repetition period advance of different constellation satellites of each GNSS system, and calculating the corresponding non-difference correction numbers of the satellites on different observation stations in each epoch, which specifically comprises the following steps:

and 3.1, reading related parameters in the broadcast ephemeris, and solving the advance of the orbit repetition period of each satellite by combining with the Keplerian third law. The realization method comprises the following steps:

step 3.1.1, firstly, acquiring parameters a and Δ n from the broadcast ephemeris (the orbit semi-major axis parameter provided in the broadcast ephemeris isDelta n is the correction quantity of the satellite angular velocity parameters), the two parameters in the broadcast ephemeris of the multi-GNSS system are updated once per hour, and a plurality of groups of satellite orbit repetition period values can be calculated for each single satellite within one day, so that the calculation values need to be averaged during statistics;

and 3.1.2, if the revolution number of the system satellite in the orbit repetition period is k.The satellite orbit repetition period T_sCan be expressed as:

wherein the content of the first and second substances,is the square root of the standard gravity parameter corresponding to each GNSS system (wherein G is the universal gravity constant, and M is the earth mass); a is the semi-major axis of the satellite orbit, and T is the time of one circle of satellite operation.

Step 3.1.3, adding T_sFurther expressed as the lead t of the track repetition period corresponding to the days:

t＝d·86400-T_s(2)

wherein d is an integer number of days corresponding to the satellite orbit repetition period.

The values of d and k corresponding to different types of satellites of each system are as follows:

TABLE 1. Each system corresponds to a whole number of days d and a number of revolution k

And (4) calculating the orbit repetition period advance of each satellite according to the step 3.1.3.

And 3.2, calculating the non-difference correction numbers corresponding to the satellites on different stations in each epoch, setting a matrix formed by the parameters of the non-difference correction numbers of the satellites on each station related to a single epoch as a parameter vector X to be solved, setting s as an observed value, namely a filtered double-difference residual value, setting a coefficient matrix corresponding to an observation equation as b, and finally setting the parameter vector containing the non-difference correction numbers corresponding to the satellites on each station to be solved as X. Assuming that a double-difference record contains stations e and f and satellites i and j, the non-difference corrections are estimated to be e and f, respectivelyAnd (3) the corresponding observation equation expansion:

bx＝s (3)

wherein:

the weight corresponding to the observation equation (3) is p, and the variance D of the double-difference residual value is set₀＝a₀In meters, a₀When the value range of (A) is set to 0.001m to 0.005m, the weight is set to p 1m/D₀. Four non-differential corrections are involved in a double-difference residual error observed value, namely a coefficient matrix b in an equation (3) contains four elements and corresponds to four elements in X, and after an index value (namely row and column numbers) of the group of elements in X is obtained, an n matrix and a w matrix corresponding to an equation of a calculation method of the following equation can be used:

n＝b^Tpb w＝b^Tps (4)

and 3.3, according to the normal equation obtained in the step 3.2, the condition of rank deficiency is bound to occur in solving the solution equation, in order to solve the problem, and meanwhile, in order to ensure the rationality of solving the non-difference correction number, an additional constraint condition needs to be added to the parameter to be estimated, and the size of the parameter to be estimated can be constrained in consideration of the fact that the numerical value of the multipath has a certain range. Then for any one parameter Z to be estimated, the observation equation at that time can be obtained according to equation (3), where:

b＝1

x＝Z

s＝0 (5)

for the additional constraint, the additional constraint is used as a virtual observation value to participate in the solution, at this time, the weight p of the constraint is determined, and the variance D of the grid point parameter is set₁＝a₁，a₁The value of (A) is generally set to 0.05m to 0.10m, and p is 1m/D₁. At this time, one data record constrains one grid point parameter, so the coefficient matrix b only relates to one element, all data records are gradually traversed, constraints are added to all grid points, and an n matrix and a w matrix corresponding to a normal equation are obtained by using a formula (5).

Step 4, obtaining a final normal equation, solving a non-difference correction number corresponding to the satellite on each station, and correcting errors caused by multipath effects in subsequent observed values by using the correction numbers, wherein the method specifically comprises the following steps:

step 4.1, superposing the corresponding N and W arrays obtained in the step 3.2 and the step 3.3 to form a normal equation coefficient array N and a normal equation constant array W, wherein the N and W arrays are the arrays involved in the normal equation when the X parameter is solved, assuming that the final parameter vector is solved as the matrix corresponding to the X is N and W, respectively, recording the positions of the N and W array elements in the N array and the W array according to the index value corresponding to the X parameter when the step 3.2-3.3 is carried out, and superposing and updating the final N array and the W array elements by the N and W arrays, wherein the following formula is utilized:

X＝N^-1W (6)

x, the non-differential corrections corresponding to the satellites at each station, can be solved.

Step 4.2, when the correction obtained in step 4.1 is used for multipath error elimination, after the relevant information (including the orbit repeat period lead) of each satellite of each station is obtained, the index can be carried out according to the station and the satellite number, and the assumption is that the satellite j on the e station in the next day needs to be observed at the observation timeThe observed value of the satellite is corrected by the multipath error, and then the satellite j on the e station is foundNon-differential correction number corresponding to timeThen will beThe observed value may be corrected as a correction number.

And 4.3, correcting the multipath effect of the observed value by all the visible satellites of all the stations by adopting the method, so that the multipath error influence can be effectively weakened in the subsequent GNSS data processing process. A

In specific implementation, the above processes can adopt computer software technology to realize automatic operation process, and a system device for operating the process of the method of the present invention should also be within the protection scope of the present invention.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.