CN105334524A - Pseudo range differential positioning method based on virtual grid - Google Patents

Abstract

The invention discloses a pseudo range differential positioning method based on a virtual grid. The invention discloses a pseudo range differential positioning method based on a virtual grid, comprising steps of adopting a pseudo range difference positioning strategy based on a grid, dividing a reference station area into a plurality of grids according to a distance or an area, adopting an interpolation method to internally interpolate a virtual observation value of a grid point, choosing a grid point which is closest to a client terminal by a data center according to the uploaded outline coordinate uploaded by the user, and transmitting a grid point virtual observation value to the user to perform the pseudo range difference positioning. In the positioning of a big area positioning, the data processing center needs to simultaneously process substantial user terminal data, and the data processing burden is heavy. The differential positioning system performs division on the foundation reinforcement area through using the grid inner interpolation mode, reduces the burden that the data processing center performs the inner interpolation calculation on every terminal. The invention can effectively solve the problem that the amount of the user is big in the sub-meter positioning and provides the solution to the high accuracy positioning of the future big data time.

Description

A kind of pseudo range difference localization method based on virtual grid

Technical field

The present invention relates to field of satellite location, particularly relate to the application of satnav in sub-meter grade Kinematic Positioning.

Background technology

In Differential positioning, can be divided into and use single base station to carry out difference modes, i.e. single base station difference.In the network that also can be made up of many base stations, use the common difference modes of multiple base station data, i.e. many base stations difference.

Single base station difference: namely reference station provides differential service for multiple user.The subject matter that single base station difference exists is: its positioning precision is along with the increase of terminal and base station distance, and positioning precision decays gradually, especially more obvious in elevation direction.Because the distance between movement station and base station decides the precision of pseudo range difference location, namely this pseudo range difference mode is subject to the restriction of distance, so be not suitable for the hi-Fix of large regions.

Select nearest base station to carry out difference in many base stations: namely according to the general location that user provides, the base station that chosen distance user is nearest from multiple base station is as reference station.Relative to single base station difference, the operating area of the method expands to some extent.But in Kinematic Positioning, due to the variation of rover station position, rover station and base station distance also change thereupon, with regard to there being the problem being faced with conversion base station, when base station distance is far away, there will be error when converting between two stations and jumping.Therefore there is the problem causing locating instability because of reference station conversion in this mode in hi-Fix.

VRS (virtual reference station) pattern: VRS pattern adopts customer position information, use many base station datas to fictionalize the virtual base station of distance users very near (being less than 100 meters), the dummy observation that user terminal utilizes virtual base station to generate carries out Differential positioning.Relative to above two kinds of modes, VRS Pattern localization precision is optimum.But Problems existing is, the heart in data handling, as long as there is a user to reach the standard grade, data processing centre (DPC) is just necessary for this user and generates a set of dummy observation.When having thousands of even more users to access simultaneously, generate a set of dummy observation if appointed for each user, greatly will increase the calculated amount of data processing centre (DPC), increase the data processing time of data processing centre (DPC).Some user's information upload data center may be caused not process in time and cause user terminal to locate delay, even data processing centre (DPC) collapses owing to cannot bear huge calculated amount.

Summary of the invention

Goal of the invention: for above-mentioned prior art, proposes a kind of pseudorange positioning system based on virtual grid, solves customer volume in sub_meter position and causes greatly locating the problem postponed.

Technical scheme: a kind of pseudo range difference localization method based on virtual grid, comprises the steps:

Step 1), by actual Reference network region stress and strain model, the node location of setting grid is the position at each virtual observation station;

Step 2), for arbitrary virtual observation station, utilize the observation data of at least three reference stations around this virtual observation station, carry out by two-dimentional difference the dummy observation that interpolation obtains this virtual observation station;

Step 3), according to the general location of user, Differential positioning is carried out as virtual reference station in the nearest virtual observation station of chosen distance customer location.

Further, described step 2) in, the observation data of described reference station comprises satellite L ₁, L ₂carrier phase observation data, C ₁, P ₂pseudo-range Observations, S ₁, S ₂signal to noise ratio (S/N ratio) observed reading; Utilize the observation data of three reference stations to carry out by two-dimentional difference the dummy observation that interpolation obtains virtual observation station, comprise the steps:

A), suppose that the latitude coordinates of three reference stations is respectively P ₁(B ₁, L ₁), P ₂(B ₂, L ₂), P ₃(B ₃, L ₃), the observation data of three reference stations is respectively i represents that reference station is numbered, i=1,2,3; The plane equation of the triangular unit that matching three reference stations are formed is:

Obs＝f(B,L)＝a ₀+a ₁B+a ₂L(1)

Wherein, coefficient a ₀, a ₁, a ₂determined by the observation data of three reference stations, as shown in equation (2):

$\left\{\begin{array}{c}{\mathrm{Obs}}_1=a_0+a_1{B}_1+a_2{L}_1\\ {\mathrm{Obs}}_1=a_0+a_1{B}_2+a_2{L}_2\\ {\mathrm{Obs}}_3=a_0+a_1{B}_3+a_2{L}_3\end{array}\right.---\left(2\right)$

Wherein, Obs ₁, Obs ₂, Obs ₃be the observation data of three reference stations, solve an equation (2) obtain coefficient a ₀, a ₁, a ₂for:

$\left\{\begin{array}{c}{a}_1=\frac{(L_1-L_3)({\mathrm{Obs}}_1-{\mathrm{Obs}}_2)-(L_1-L_2)({\mathrm{Obs}}_1-{\mathrm{Obs}}_3)}{(B_1-B_2)(L_1-L_3)-(B_1-B_3)(L_1-L_2)}\\ a_2=\frac{(B_1-B_3)({\mathrm{Obs}}_1-{\mathrm{Obs}}_2)-(B_1-B_2)({\mathrm{Obs}}_1-{\mathrm{Obs}}_3)}{(B_1-B_3)(L_1-L_2)-(B_1-B_2)(L_1-L_3)}\\ a_0={\mathrm{Obs}}_1-a_1{B}_1-a_2{L}_1\end{array}\right.---\left(3\right)$

B), by the observation data Obs of three reference stations ₁, Obs ₂, Obs ₃use reference station observed reading C respectively ₁, P ₂, L ₁, L ₂, S ₁, S ₂substitute into, try to achieve the coefficient a that often kind of observed reading is corresponding ₀, a ₁, a ₂; Then longitude and latitude B, the L at each virtual observation station are substituted into coefficient determined (1) formula corresponding to often kind of observed reading, obtain the dummy observation C at virtual observation station ₁, P ₂, L ₁, L ₂, S ₁, S ₂.

Further, described step 3) in, according to the virtual observation station that formula (4) matching distance customer location is nearest:

$\left\{\begin{array}{c}{N}_x=\[\frac{X-X_{MIN}}{d}\]\\ N_y=\[\frac{Y-Y_{MIN}}{d}\]\end{array}\right.---\left(4\right)$

Wherein, N _x, N _ybe respectively nearest virtual observation station, distance users position line number within a grid and row number; [] is the operator that rounds up; X, Y are the general location coordinate of user; X _mIN, Y _mINbe respectively the coordinate longitude at each virtual observation station, latitude minimum value; D is mesh spacing.

Beneficial effect: the inventive method is passed through actual Reference network region stress and strain model, the node location of setting grid is the position at each virtual observation station, carrys out by three or multiple reference station around arbitrary virtual observation station the dummy observation that interpolation obtains virtual observation station; Then according to the rough coordinates that user is transmitted, the virtual observation station that chosen distance user is nearest, send to user terminal after being encoded by the dummy observation at this virtual observation station, user utilizes the dummy observation of acquisition to carry out Differential positioning.Because actual Reference network region grid divides according to certain intervals, its position does not change, therefore no matter data processing centre (DPC) has how many user terminals to reach the standard grade at one time, data processing centre (DPC) all again for user generates new dummy observation, need not greatly reduce data terminal calculated amount.For the whole nation, the long 5200km of Chinese thing, north and south 5500km, various vehicle and personal user's hypothesis have 100,000,000, if 30km is a grid, the number needing the virtual observation station generated is 5200/30 × 5500/30=31778, namely needs calculating 31778 times.If adopt VRS pattern, 100,000,000 users, just need generation 100,000,000 virtual observation stations.The inventive method is namely based on the pseudorange differential method of grid, and calculated amount, also less than 0.05% of VRS pattern, obviously adopts method of the present invention greatly can improve counting yield.Certainly suppose the thing of regional herein, North and South direction calculating when be all maximum.In fact in state-owned 9,600,000 square kilometres, if calculate grid number with area, then only 960 × 10000/ (30 × 30)=10667 virtual reference station are needed.30km spacing is selected to carry out grid division herein, because the noise of Pseudo-range Observations own is larger, in 30km, RTD positioning precision depends primarily on pseudorange quality, so only need with 30km, what there is no need stress and strain model is too close, if spacing is relaxed to 50km, the advantage obviously based on the pseudo range difference localization method of grid will be more obvious.

Accompanying drawing explanation

Fig. 1 is the system topological figure of the pseudo range difference localization method based on virtual grid;

Fig. 2 is the flow chart of data processing figure of the pseudo range difference localization method based on virtual grid;

Fig. 3 is actual Reference network region stress and strain model schematic diagram;

Fig. 4 is the dummy observation schematic diagram at triangulation network Form generation virtual observation station.

Embodiment

Below in conjunction with accompanying drawing the present invention done and further explain.

Based on a pseudo range difference localization method for virtual grid, the method based on system comprise actual Reference network, virtual grid reference station generation server, differential data forwarding server and sub_meter position terminal user, as shown in Figure 1.Pseudo range difference localization method based on virtual grid comprises the steps:

Step 1), utilize virtual grid reference station generation server, by actual Reference network region stress and strain model, the node location of setting grid is the position at each virtual observation station.As shown in Figure 3, in the present embodiment, have five reference stations in actual Reference network, i.e. base station A-E, according to dimension (B maximum in reference station _mAX), smallest dimension (B _mIN), maximum longitude (L _mAX), minimum longitude (L _mIN), be the square node that three row three arrange by the Region dividing at A-E place, base station, mesh lines spacing is d, obtains nine virtual observation stations that sequence number is 1-9, and determines the geographic coordinate at these nine virtual observation stations; In grid, left and right corner and sequence number are the coordinate figure at the virtual observation station of 9 is (X _mIN, Y _mIN).

Step 2), each reference station Real-time Collection Satellite Observations also carries out pre-service to data, and observation data comprises satellite L ₁, L ₂carrier phase observation data, C ₁, P ₂pseudo-range Observations, S ₁, S ₂signal to noise ratio (S/N ratio) observed reading.Because level location in track is only concerned about that elevation information is not considered in planimetric position two, therefore be arbitrary virtual observation station in nine virtual observation stations of 1-9 for sequence number, utilize the observation data of three reference stations around this virtual observation station, carry out by two-dimentional difference the dummy observation that interpolation obtains this virtual observation station.

The virtual observation station that the present embodiment is 5 for sequence number is described, and as shown in Figure 4, the dummy observation concrete steps obtaining this virtual observation station are:

A), choose three reference stations around this virtual observation station, i.e. base station A, base station D, base station E, the latitude coordinates of these three reference stations is respectively P ₁(B ₁, L ₁), P ₂(B ₂, L ₂), P ₃(B ₃, L ₃), the observation data of three reference stations is respectively i represents that reference station is numbered, i=1,2,3.The plane equation of the triangular unit that these three reference stations of matching are formed is:

Obs＝f(B,L)＝a ₀+a ₁B+a ₂L(1)

Wherein, coefficient a ₀, a ₁, a ₂uniquely determined by the observation data of three reference stations, as shown in equation (2):

$\left\{\begin{array}{c}{\mathrm{Obs}}_1=a_0+a_1{B}_1+a_2{L}_1\\ {\mathrm{Obs}}_1=a_0+a_1{B}_2+a_2{L}_2\\ {\mathrm{Obs}}_3=a_0+a_1{B}_3+a_2{L}_3\end{array}\right.---\left(2\right)$

Wherein, Obs ₁, Obs ₂, Obs ₃be the observation data of three reference stations, solve an equation (2) obtain coefficient a ₀, a ₁, a ₂for:

$\left\{\begin{array}{c}{a}_1=\frac{(L_1-L_3)({\mathrm{Obs}}_1-{\mathrm{Obs}}_2)-(L_1-L_2)({\mathrm{Obs}}_1-{\mathrm{Obs}}_3)}{(B_1-B_2)(L_1-L_3)-(B_1-B_3)(L_1-L_2)}\\ a_2=\frac{(B_1-B_3)({\mathrm{Obs}}_1-{\mathrm{Obs}}_2)-(B_1-B_2)({\mathrm{Obs}}_1-{\mathrm{Obs}}_3)}{(B_1-B_3)(L_1-L_2)-(B_1-B_2)(L_1-L_3)}\\ a_0={\mathrm{Obs}}_1-a_1{B}_1-a_2{L}_1\end{array}\right.---\left(3\right)$

B), by the observation data Obs of three reference stations ₁, Obs ₂, Obs ₃use reference station observed reading C successively respectively ₁, P ₂, L ₁, L ₂, S ₁, S ₂substitute into, try to achieve the coefficient a that often kind of observed reading is corresponding ₀, a ₁, a ₂.Then longitude and latitude B, the L at each virtual observation station are substituted into coefficient determined (1) formula corresponding to often kind of observed reading, obtain the dummy observation C at virtual observation station ₁, P ₂, L ₁, L ₂, S ₁, S ₂.

With Pseudo-range Observations C ₁for example, the pseudorange C of three reference stations ₁observation data is Obs ₁(C ₁ ¹), Obs ₂(C ₁ ²), Obs ₃(C ₁ ³), substitute into formula (3) and obtain:

$\left\{\begin{array}{c}{a}_1=\frac{(L_1-L_3)\left({\mathrm{Obs}}_1\right({C_1}^1)-{\mathrm{Obs}}_2({C_1}^2\left)\right)-(L_1-L_2)\left({\mathrm{Obs}}_1\right({C_1}^1)-{\mathrm{Obs}}_3({C_1}^3\left)\right)}{(B_1-B_2)(L_1-L_3)-(B_1-B_3)(L_1-L_2)}\\ a_2=\frac{(B_1-B_3)\left({\mathrm{Obs}}_1\right({C_1}^1)-{\mathrm{Obs}}_2({C_1}^2\left)\right)-(B_1-B_2)\left({\mathrm{Obs}}_1\right({C_1}^1)-{\mathrm{Obs}}_3({C_1}^3\left)\right)}{(B_1-B_3)(L_1-L_2)-(B_1-B_2)(L_1-L_3)}\\ a_0={\mathrm{Obs}}_1\left({C_1}^1\right)-a_1{B}_1-a_2{L}_1\end{array}\right.---\left(4\right)$

According to the coefficient a that formula (4) obtains ₀, a ₁, a ₂the formula (1) determined, substituting into sequence number is the longitude and latitude at the virtual observation station of 5, namely obtain sequence number be the virtual observation station of 5 pseudorange C ₁observed reading.Sequence number is the dummy observation P at the virtual observation station of 5 ₂, L ₁, L ₂, S ₁, S ₂acquisition methods in like manner.It should be noted that, when calculating sequence number is the dummy observation at virtual observation station of 5, also can selects other combinations such as base station A, base station B, base station D, need determine that this virtual observation erect-position is in three the determined delta-shaped regions in base station chosen.

According to a) to all observation datas b) in like manner obtaining nine virtual observation stations.

Step 3), its general location is uploaded to differential data forwarding server when needs are located by hardware devices such as mobile base stations by sub_meter position terminal user, server is according to the general location of user, according to the virtual observation station that formula (5) matching distance customer location is nearest, then user terminal is sent to after the observation data at the virtual observation station selected being encoded, family terminal utilizes the dummy observation sent to carry out pseudo range difference, determines terminal user position.

$\left\{\begin{array}{c}{N}_x=\[\frac{X-X_{MIN}}{d}\]\\ N_y=\[\frac{Y-Y_{MIN}}{d}\]\end{array}\right.---\left(5\right)$

Wherein, N _x, N _ybe respectively nearest virtual observation station, distance users position line number within a grid and row number; [] is the operator that rounds up; X, Y are the general location coordinate of user; X _mIN, Y _mINnamely be respectively the coordinate longitude at each virtual observation station, latitude minimum value, be the coordinate at the virtual observation station of 9 with sequence number at the present embodiment; D is mesh lines spacing.

In large regions Ya meter Ji locates, data processing centre (DPC) needs to process a large number of users terminal data simultaneously, and obvious data processing load is heavy.The differential position system that the present invention builds is by using grid interpolation pattern, ground is strengthened region plan, minimizing data processing centre (DPC) carries out interpolation to each terminal and calculates the server computation burden brought, the present invention effectively can solve the large problem of customer volume in sub_meter position, and for future, the hi-Fix of large data age provides solution.

The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (3)

1., based on a pseudo range difference localization method for virtual grid, it is characterized in that, comprise the steps:

Step 1), by actual Reference network region stress and strain model, the node location of setting grid is the position at each virtual observation station;

Step 2), for arbitrary virtual observation station, utilize the observation data of at least three reference stations around this virtual observation station, carry out by two-dimentional difference the dummy observation that interpolation obtains this virtual observation station;

Step 3), according to the general location of user, Differential positioning is carried out as virtual reference station in the nearest virtual observation station of chosen distance customer location.

2. a kind of pseudo range difference localization method based on virtual grid according to claim 1, is characterized in that: described step 2) in, the observation data of described reference station comprises satellite L ₁, L ₂carrier phase observation data, C ₁, P ₂pseudo-range Observations, S ₁, S ₂signal to noise ratio (S/N ratio) observed reading; Utilize the observation data of three reference stations to carry out by two-dimentional difference the dummy observation that interpolation obtains virtual observation station, comprise the steps:

A), suppose that the latitude coordinates of three reference stations is respectively P ₁(B ₁, L ₁), P ₂(B ₂, L ₂), P ₃(B ₃, L ₃), the observation data of three reference stations is respectively i represents that reference station is numbered, i=1,2,3; The plane equation of the triangular unit that matching three reference stations are formed is:

Obs＝f(B,L)＝a ₀+a ₁B+a ₂L(1)

Wherein, coefficient a ₀, a ₁, a ₂determined by the observation data of three reference stations, as shown in equation (2):

$\left\{\begin{array}{c}{\mathrm{Obs}}_1=a_0+a_1{B}_1+a_2{L}_1\\ {\mathrm{Obs}}_1=a_0+a_1{B}_2+a_2{L}_2\\ {\mathrm{Obs}}_3=a_0+a_1{B}_3+a_2{L}_3\end{array}\right.---\left(2\right)$

Wherein, Obs ₁, Obs ₂, Obs ₃be the observation data of three reference stations, solve an equation (2) obtain coefficient a ₀, a ₁, a ₂for:

$\left\{\begin{array}{c}{a}_1=\frac{(L_1-L_3)({\mathrm{Obs}}_1-{\mathrm{Obs}}_2)-(L_1-L_2)({\mathrm{Obs}}_1-{\mathrm{Obs}}_3)}{(B_1-B_2)(L_1-L_3)-(B_1-B_3)(L_1-L_2)}\\ a_2=\frac{(B_1-B_3)({\mathrm{Obs}}_1-{\mathrm{Obs}}_2)-(B_1-B_2)({\mathrm{Obs}}_1-{\mathrm{Obs}}_3)}{(B_1-B_3)(L_1-L_2)-(B_1-B_2)(L_1-L_3)}\\ a_0={\mathrm{Obs}}_1-a_1{B}_1-a_2{L}_1\end{array}\right.---\left(3\right)$

B), by the observation data Obs of three reference stations ₁, Obs ₂, Obs ₃use reference station observed reading C respectively ₁, P ₂, L ₁, L ₂, S ₁, S ₂substitute into, try to achieve the coefficient a that often kind of observed reading is corresponding ₀, a ₁, a ₂; Then longitude and latitude B, the L at each virtual observation station are substituted into coefficient determined (1) formula corresponding to often kind of observed reading, obtain the dummy observation C at virtual observation station ₁, P ₂, L ₁, L ₂, S ₁, S ₂.

3. a kind of pseudo range difference localization method based on virtual grid according to claim 1 and 2, is characterized in that: described step 3) in, according to the virtual observation station that formula (4) matching distance customer location is nearest:

$\left\{\begin{array}{c}{N}_x=\[\frac{X-X_{MIN}}{d})\\ N_y=\[\frac{Y-Y_{MIN}}{d}\]\end{array}\right.---\left(4\right)$

Wherein, N _x, N _ybe respectively nearest virtual observation station, distance users position line number within a grid and row number; [] is the operator that rounds up; X, Y are the general location coordinate of user; X _mIN, Y _mINbe respectively the coordinate longitude at each virtual observation station, latitude minimum value; D is mesh spacing.