CN106295116A - A kind of method and device determining whole world plasma layer model - Google Patents

Abstract

The present invention provides a kind of method and device determining whole world plasma layer model, belongs to Global Navigation System and Space environment monitor field.For solving the global plasma layer model of existing foundation, to there is ratio of precision relatively low, and the problem of poor reliability.Including: the observation data at COSMIC satellite top are carried out pretreatment, by obtaining the total electron content STEC in signal propagation path in described observation data；By PEC=podTEC × mf, described STEC is converted to the plasmasphere electron content PEC of zenith direction；Utilize and described PEC is fitted, determine the global plasma layer model of observation data based on described COSMIC satellite top.

Description

A kind of method and device determining whole world plasma layer model

Technical field

The invention belongs to Global Navigation System and Space environment monitor field, more particularly relate to one determine the whole world wait from The method and device of sublayer model.

Background technology

Utilize low orbit satellite GPS (English is: Global Positioning System, Chinese be called for short: global location System) top measurement data set up GPM (English is: Global Plasmasphere Model, Chinese be called for short: the whole world wait from Daughter layer model) it is plasmasphere change in time and space, ionosphere, top and plasmasphere coupling mechanism in research global range And the important means of high-precision signal delay is provided.

The vertical altitude meter in traditional modeling method such as ground combines GPS observational data, owing to the station that sets of vertical altitude meter is wanted Ask, detect the restriction of height, cause model that the method sets up precision in the world and Reliability comparotive low, particularly Applying when sea sample and arctic regions, precision and reliability are lower.Aeronautical satellite and low orbit satellite simultaneous observation data ask poor Method, the height being not necessarily exactly plasmasphere due to two kinds of satellite orbital altitude differences is interval, so equally cannot be entirely (English is: Plasmaspheric Electron Content, and Chinese is called for short: plasma to obtain high-precision PEC in the range of ball Body layer Vertical electron content).

In sum, using existing method, it is relatively low to there is ratio of precision in the global plasma layer model of foundation, and reliability The problem of difference.

Summary of the invention

The embodiment of the present invention provides a kind of method and device determining whole world plasmasphere model, in order to solve prior art Method, it is relatively low to there is ratio of precision in the global plasma layer model set up, and the problem of poor reliability.

The embodiment of the present invention provides a kind of method determining whole world plasma layer model, including:

The observation data at COSMIC satellite top are carried out pretreatment, by formula (1) from the described observation number of pretreatment According to the total electron content STEC in interior acquisition signal propagation path；

By formula (2), described STEC is converted to the plasmasphere electron content PEC of zenith direction；

Utilize spheric harmonic function model that described PEC is fitted, determine observation number based on described COSMIC satellite top According to global plasma layer model；

Wherein, described formula (1) is as follows:

$STEC=\frac{f_1^2{f}_2^2}{40.3\·(f_1^2-f_2^2)}(P_2-P_1+{\mathrm{\Δb}}_k+{\mathrm{\Δb}}^s)$

Described formula (2) is as follows:

PEC=podTEC × mf

Described spheric harmonic function model is as follows:

$VTEC(\mathrm{\β},s)=\underset{n=0}{\overset{N}{\Σ}}\underset{m=0}{\overset{N}{\Σ}}{\tilde{P}}_{nm}\left(sin\mathrm{\β}\right)\left({\tilde{C}}_{nm}cos\right(ms)+{\tilde{S}}_{nm}sin(ms\left)\right)$

In above-mentioned formula, P₁、P₂It is survey code Pseudo-range Observations, f in two frequencies₁、f₂For the frequency of carrier wave, Δ b_k, Δ b^s It is respectively receiver and the hardware delay deviation of satellite,R_pp=R_e+H_pp, R_orb=R_e+H_orb, e is the elevation angle of signal propagation path, R_eFor earth radius, H_ppIt is that LEO-GPS satellite links is at plasma Point of puncture height in body layer, H_ppSpan is hundreds of to thousand of kilometers, H_orbBeing the orbit altitude of low orbit satellite, β is for puncturing The latitude of point, s is point of puncture solar hour angle under day is admittedly, and N is that the maximum of spheric harmonic function launches exponent number,For n The naturalization Legendre function on degree m rank,WithFor spheric harmonic function coefficient, mf is conversion factor.

The embodiment of the present invention also provides for a kind of device determining whole world plasma layer model, including:

Processing unit, for carrying out pretreatment, by formula (1) from pretreatment to the observation data at COSMIC satellite top Described observation data in obtain the total electron content STEC in signal propagation path；

Converting unit, for by formula (2), is converted to the plasmasphere electron content of zenith direction by described STEC PEC；

Determine unit, be used for utilizing spheric harmonic function model that described PEC is fitted, determine based on described COSMIC satellite The global plasma layer model of the observation data at top；

Wherein, described formula (1) is as follows:

$STEC=\frac{f_1^2{f}_2^2}{40.3\·(f_1^2-f_2^2)}(P_2-P_1+{\mathrm{\Δb}}_k+{\mathrm{\Δb}}^s)$

Described formula (2) is as follows:

PEC=podTEC × mf

Described spheric harmonic function model is as follows:

$VTEC(\mathrm{\β},s)=\underset{n=0}{\overset{N}{\Σ}}\underset{m=0}{\overset{n}{\Σ}}{\tilde{P}}_{nm}\left(sin\mathrm{\β}\right)\left({\tilde{C}}_{nm}cos\right(ms)+{\tilde{S}}_{nm}sin(ms\left)\right)$

In above-mentioned formula, P₁、P₂It is survey code Pseudo-range Observations, f in two frequencies₁、f₂For the frequency of carrier wave, Δ b_k, Δ b^s It is respectively receiver and the hardware delay deviation of satellite,R_pp=R_e+H_pp, R_orb=R_e+H_orb, e is the elevation angle of signal propagation path, R_eFor earth radius, H_ppIt is that LEO-GPS satellite links is at plasma Point of puncture height in body layer, H_ppSpan is hundreds of to thousand of kilometers, H_orbBeing the orbit altitude of low orbit satellite, β is for puncturing The latitude of point, s is point of puncture solar hour angle under day is admittedly, and N is that the maximum of spheric harmonic function launches exponent number,For The naturalization Legendre function on n degree m rank,WithFor spheric harmonic function coefficient, mf is conversion factor.

During the present invention implements, it is provided that a kind of method and device determining whole world plasma layer model, including to COSMIC The observation data at satellite top carry out pretreatment, pass throughFrom described sight The total electron content STEC in signal propagation path is obtained in surveying；By formula PEC=podTEC × mf, described signal is propagated The total electron content in direction is converted to the plasmasphere electron content PEC of zenith direction；Utilize spheric harmonic function modelDescribed PEC is fitted, determines and defend based on described COSMIC The global plasma layer model of the observation data at star top；In above-mentioned formula, P₁、P₂It it is survey code pseudorange observation in two frequencies Value, f₁、f₂For the frequency of carrier wave, Δ b_k, Δ b^sIt is respectively receiver and the hardware delay deviation of satellite,R_pp=R_e+H_pp, R_orb=R_e+H_orb, e is the height of signal propagation path Angle, R_eFor earth radius, H_ppIt is LEO-GPS satellite links point of puncture height in plasmasphere, H_ppSpan is several Hundred arrive thousand of kilometers, H_orbBeing the orbit altitude of low orbit satellite, β is the latitude of point of puncture, s be point of puncture under day is admittedly too Sun hour angle, N is that the maximum of spheric harmonic function launches exponent number,For the naturalization Legendre function on n degree m rank,With For spheric harmonic function coefficient, mf is conversion factor.In the embodiment of the present invention, due to can from the top of low orbit satellite is measured directly Extract the electron content of plasmasphere, thus eliminate the error produced due to observed pattern etc., improve model further and exist Precision in global range and reliability.

Accompanying drawing explanation

In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing In having technology to describe, the required accompanying drawing used is briefly described, it should be apparent that, the accompanying drawing in describing below is only this Some embodiments of invention, for those of ordinary skill in the art, on the premise of not paying creative work, it is also possible to Other accompanying drawing is obtained according to these accompanying drawings.

The determination method flow schematic diagram of a kind of Global Ionospheric grid model that Fig. 1 provides for the embodiment of the present invention；

Fig. 2 provides the determination apparatus structure schematic diagram of a kind of Global Ionospheric grid model for the embodiment of the present invention.

Detailed description of the invention

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete Describe, it is clear that described embodiment is only a part of embodiment of the present invention rather than whole embodiments wholely.Based on Embodiment in the present invention, it is every other that those of ordinary skill in the art are obtained under not making creative work premise Embodiment, broadly falls into the scope of protection of the invention.

A kind of method flow schematic diagram determining global layer model of surely leaving office that Fig. 1 provides for the embodiment of the present invention.Such as Fig. 1 Shown in, the method mainly comprises the steps that

The observation data at COSMIC satellite top are carried out pretreatment by step 101, by formula (1) from the institute of pretreatment The total electron content STEC in signal propagation path is obtained in stating observation data；

Step 102, by formula (2), is converted to the plasmasphere electron content PEC of zenith direction by described STEC；

Step 103, utilizes spheric harmonic function model to be fitted described PEC, determines based on described COSMIC satellite top The global plasma layer model of observation data；

Wherein, described formula (1) is as follows:

$STEC=\frac{f_1^2{f}_2^2}{40.3\·(f_1^2-f_2^2)}(P_2-P_1+{\mathrm{\Δb}}_k+{\mathrm{\Δb}}^s)$

Described formula (2) is as follows:

PEC=podTEC × mf

Described spheric harmonic function model is as follows:

$VTEC(\mathrm{\β},s)=\underset{n=0}{\overset{N}{\Σ}}\underset{m=0}{\overset{n}{\Σ}}{\tilde{P}}_{nm}\left(sin\mathrm{\β}\right)\left({\tilde{C}}_{nm}cos\right(ms)+{\tilde{S}}_{nm}sin(ms\left)\right)$

In above-mentioned formula, P₁、P₂It is survey code Pseudo-range Observations, f in two frequencies₁、f₂For the frequency of carrier wave, Δ b_k, Δ b^s It is respectively receiver and the hardware delay deviation of satellite,R_pp=R_e+H_pp, R_orb=R_e+H_orb, e is the elevation angle of signal propagation path, R_eFor earth radius, H_ppIt is that LEO-GPS satellite links is at plasma Point of puncture height in body layer, H_ppSpan is hundreds of to thousand of kilometers, H_orbBeing the orbit altitude of low orbit satellite, β is for puncturing The latitude of point, s is point of puncture solar hour angle under day is admittedly, and N is that the maximum of spheric harmonic function launches exponent number,For The naturalization Legendre function on n degree m rank,WithFor spheric harmonic function coefficient, mf is conversion factor.

In a step 101, all of initial data derives from COSMIC (English is: The Constellation Observing System for Meteorology, Ionosphere and Climate) satellite GPS receiver disposed above The observation signal that machine receives during satellite flight, the top observation signal receiving GPS stores, To top observed data.

By formula (1), (English is: Slant Total to obtain STEC signal propagation path in top observation data Electron Content, Chinese is called for short: total electron content)

$STEC=\frac{f_1^2{f}_2^2}{40.3\·(f_1^2-f_2^2)}(P_2-P_1+{\mathrm{\Δb}}_k+{\mathrm{\Δb}}^s)---\left(1\right)$

In formula (1), P₁, P₂It is respectively L₁、L₂Survey code Pseudo-range Observations, f₁、f₂For L₁、L₂The frequency of carrier wave, Δ b_k、 Δb^sIt is respectively receiver and satellite hardware delay distortion.

It should be noted that in actual applications, the height of COSMIC satellite flight about about 800km height, In solar activity low year, this height can approximate the transition altitude regarding ionosphere as with plasmasphere, therefore COSMIC satellite Highly arrive the vertical height integrated electronic content between gps satellite height to approximate and regard PEC as.Owing to podTEC data are given It is LEO-GPS wrong path footpath integrated electronic content along thread path, in order to ask for the PEC of vertical direction (i.e. zenith direction), must Suitable conversion factor mf must be chosen and the podTEC of oblique path direction is converted into the PEC of vertical direction.

Specifically, in a step 102, by formula (2), STEC is converted to the PEC of zenith direction.Formula (2) is as follows Shown in:

PEC=podTEC × mf (2)

Wherein,R_pp=R_e+H_pp, R_orb=R_e+H_orb, mf is conversion The factor, e is the elevation angle of signal propagation path, R_eFor earth radius, H_ppIt is that LEO-GPS satellite links is in plasmasphere Point of puncture height, H_orbIt is the orbit altitude of low orbit satellite, H_ppSpan is hundreds of to thousand of kilometers.

In step 103, utilize spheric harmonic function model that PEC is fitted, determine based on described COSMIC satellite top The global plasma layer model of observation data, specifically, formula (3) is as follows:

$VTEC(\mathrm{\β},s)=\underset{n=0}{\overset{N}{\Σ}}\underset{m=0}{\overset{n}{\Σ}}{\tilde{P}}_{nm}\left(sin\mathrm{\β}\right)\left({\tilde{C}}_{nm}cos\right(ms)+{\tilde{S}}_{nm}sin(ms\left)\right)---\left(3\right)$

Wherein, β is the latitude of point of puncture, and s is point of puncture solar hour angle under day is admittedly, and N is the maximum of spheric harmonic function Launch exponent number,For the naturalization Legendre function on n degree m rank,WithFor spheric harmonic function coefficient.

It should be noted that in embodiments of the present invention, the spheric harmonic function model of employing is also used for setting up Global Ionospheric Grid model, CODE uses the spheric harmonic function model on 15 × 15 rank to set up Global Ionospheric grid model.

Further, owing to relative to ionosphere, the magnitude of the TEC of plasmasphere is less, the complexity of internal structure It is relatively little, so the method using the spheric harmonic function on 8 × 8 rank to combine least square is modeled.Modeling is estimated to connect simultaneously The hardware delay deviation of receipts machine and satellite, in order to be separated with the hardware delay of satellite by receiver, addition of when parameter estimation All satellite null constraintss of DCB sum.

In sum, the present invention implements to provide a kind of method determining whole world plasma layer model, due to can be from The electron content of extracting directly plasmasphere in the top measurement of low orbit satellite, thus eliminate and produce due to observed pattern etc. Error, improve further model precision in the world and reliability.

Based on same inventive concept, embodiments provide a kind of device determining whole world plasma layer model, Because to a kind of, the principle of this device solution technical problem determines that the method for whole world plasma layer model is similar, therefore this device Enforcement may refer to the enforcement of method, repeat no more in place of repetition.

A kind of apparatus structure schematic diagram determining whole world plasma layer model that Fig. 2 provides for the embodiment of the present invention.As Shown in Fig. 2, this device includes processing unit 21, converting unit 22 and determine unit 23.

Processing unit 21, for carrying out pretreatment to the observation data at COSMIC satellite top, by formula (1) from pre- The total electron content STEC in signal propagation path is obtained in the described observation data of reason；

Converting unit 22, for being converted to the plasmasphere electron content PEC of zenith direction by described STEC；

Determine unit 23, be used for utilizing spheric harmonic function model that described PEC is fitted, determine and defend based on described COSMIC The global plasma layer model of the observation data at star top；

Wherein, described formula (1) is as follows:

$STEC=\frac{f_1^2{f}_2^2}{40.3\·(f_1^2-f_2^2)}(P_2-P_1+{\mathrm{\Δb}}_k+{\mathrm{\Δb}}^s)$

Described formula (2) is as follows:

PEC=podTEC × mf

Described spheric harmonic function model is as follows:

$VTEC(\mathrm{\β},s)=\underset{n=0}{\overset{N}{\Σ}}\underset{m=0}{\overset{n}{\Σ}}{\tilde{P}}_{nm}\left(sin\mathrm{\β}\right)\left({\tilde{C}}_{nm}cos\right(ms)+{\tilde{S}}_{nm}sin(ms\left)\right)$

In above-mentioned formula, P₁、P₂It is survey code Pseudo-range Observations, f in two frequencies₁、f₂For the frequency of carrier wave, Δ b_k, Δ b^s It is respectively receiver and the hardware delay deviation of satellite,R_pp=R_e+H_pp, R_orb=R_e+H_orb, e is the elevation angle of signal propagation path, R_eFor earth radius, H_ppIt is that LEO-GPS satellite links is at plasma Point of puncture height in body layer, H_ppSpan is hundreds of to thousand of kilometers, H_orbBeing the orbit altitude of low orbit satellite, β is for puncturing The latitude of point, s is point of puncture solar hour angle under day is admittedly, and N is that the maximum of spheric harmonic function launches exponent number,For The naturalization Legendre function on n degree m rank,WithFor spheric harmonic function coefficient, mf is conversion factor.

Should be appreciated that one of the above determines this equipment according to the unit that includes of device of whole world plasma layer model is only The logical partitioning that the function that device realizes is carried out, in actual application, can carry out superposition or the fractionation of said units.And this is real The one that the function that a kind of device determining whole world plasma layer model that executing example provides is realized provides with above-described embodiment Determine the whole world plasma layer model method one_to_one corresponding, the more detailed handling process that this device is realized, Said method embodiment one is described in detail, is not described in detail herein.

Those skilled in the art are it should be appreciated that embodiments of the invention can be provided as method, system or computer program Product.Therefore, the reality in terms of the present invention can use complete hardware embodiment, complete software implementation or combine software and hardware Execute the form of example.And, the present invention can use at one or more computers wherein including computer usable program code The upper computer program product implemented of usable storage medium (including but not limited to disk memory, CD-ROM, optical memory etc.) The form of product.

The present invention is with reference to method, equipment (system) and the flow process of computer program according to embodiments of the present invention Figure and/or block diagram describe.It should be understood that can the most first-class by computer program instructions flowchart and/or block diagram Flow process in journey and/or square frame and flow chart and/or block diagram and/or the combination of square frame.These computer programs can be provided Instruction arrives the processor of general purpose computer, special-purpose computer, Embedded Processor or other programmable data processing device to produce A raw machine so that the instruction performed by the processor of computer or other programmable data processing device is produced for real The device of the function specified in one flow process of flow chart or multiple flow process and/or one square frame of block diagram or multiple square frame now.

These computer program instructions may be alternatively stored in and computer or other programmable data processing device can be guided with spy Determine in the computer-readable memory that mode works so that the instruction being stored in this computer-readable memory produces and includes referring to Make the manufacture of device, this command device realize at one flow process of flow chart or multiple flow process and/or one square frame of block diagram or The function specified in multiple square frames.

These computer program instructions also can be loaded in computer or other programmable data processing device so that at meter Perform sequence of operations step on calculation machine or other programmable devices to produce computer implemented process, thus at computer or The instruction performed on other programmable devices provides for realizing at one flow process of flow chart or multiple flow process and/or block diagram one The step of the function specified in individual square frame or multiple square frame.

Although preferred embodiments of the present invention have been described, but those skilled in the art once know basic creation Property concept, then can make other change and amendment to these embodiments.So, claims are intended to be construed to include excellent Select embodiment and fall into all changes and the amendment of the scope of the invention.

Obviously, those skilled in the art can carry out various change and the modification essence without deviating from the present invention to the present invention God and scope.So, if these amendments of the present invention and modification belong to the scope of the claims in the present invention and equivalent technologies thereof Within, then the present invention is also intended to comprise these change and modification.

Claims (2)

1. the method determining whole world plasma layer model, it is characterised in that including:

The observation data at COSMIC satellite top are carried out pretreatment, by formula (1) in the described observation data of pretreatment Obtain the total electron content STEC in signal propagation path；

By formula (2), described STEC is converted to the plasmasphere electron content PEC of zenith direction；

Utilize spheric harmonic function model that described PEC is fitted, determine observation data based on described COSMIC satellite top Whole world plasma layer model；

Wherein, described formula (1) is as follows:

$STEC=\frac{f_1^2{f}_2^2}{40.3\·(f_1^2-f_2^2)}(P_2-P_1+{\mathrm{\Δb}}_k+{\mathrm{\Δb}}^s)$

Described formula (2) is as follows:

PEC=podTEC × mf

Described spheric harmonic function model is as follows:

$VTEC(\mathrm{\β},s)=\underset{n=0}{\overset{N}{\Σ}}\underset{m=0}{\overset{n}{\Σ}}{\tilde{P}}_{nm}\left(sin\mathrm{\β}\right)\left({\tilde{C}}_{nm}cos\right(ms)+{\tilde{S}}_{nm}sin(ms\left)\right)$

In above-mentioned formula, P₁、P₂It is survey code Pseudo-range Observations, f in two frequencies₁、f₂For the frequency of carrier wave, Δ b_k, Δ b^sRespectively For the hardware delay deviation of receiver and satellite,

R_pp=R_e+H_pp, R_orb=R_e+H_orb, e is the height of signal propagation path Degree angle, R_eFor earth radius, H_ppIt is LEO-GPS satellite links point of puncture height in plasmasphere, H_ppSpan is Hundreds of to thousand of kilometers, H_orbBeing the orbit altitude of low orbit satellite, β is the latitude of point of puncture, and s is that point of puncture is under day is admittedly Solar hour angle, N is that the maximum of spheric harmonic function launches exponent number,For the naturalization Legendre function on n degree m rank,WithFor spheric harmonic function coefficient, mf is conversion factor.

2. the device determining whole world plasma layer model, it is characterised in that including:

Processing unit, for carrying out pretreatment, by formula (1) from the institute of pretreatment to the observation data at COSMIC satellite top The total electron content STEC in signal propagation path is obtained in stating observation data；

Converting unit, for by formula (2), is converted to the plasmasphere electron content PEC of zenith direction by described STEC；

Determine unit, be used for utilizing spheric harmonic function model that described PEC is fitted, determine based on described COSMIC satellite top The global plasma layer model of observation data；

Wherein, described formula (1) is as follows:

$STEC=\frac{f_1^2{f}_2^2}{40.3\·(f_1^2-f_2^2)}(P_2-P_1+{\mathrm{\Δb}}_k+{\mathrm{\Δb}}^s)$

Described formula (2) is as follows:

PEC=podTEC × mf

Described spheric harmonic function model is as follows:

$VTEC(\mathrm{\β},s)=\underset{n=0}{\overset{N}{\Σ}}\underset{m=0}{\overset{n}{\Σ}}{\tilde{P}}_{nm}\left(sin\mathrm{\β}\right)\left({\tilde{C}}_{nm}cos\right(ms)+{\tilde{S}}_{nm}sin(ms\left)\right)$

In above-mentioned formula, P₁、P₂It is survey code Pseudo-range Observations, f in two frequencies₁、f₂For the frequency of carrier wave, Δ b_k, Δ b^sRespectively For the hardware delay deviation of receiver and satellite,

R_pp=R_e+H_pp, R_orb=R_e+H_orb, e is the height of signal propagation path Degree angle, R_eFor earth radius, H_ppIt is LEO-GPS satellite links point of puncture height in plasmasphere, H_ppSpan is Hundreds of to thousand of kilometers, H_orbBeing the orbit altitude of low orbit satellite, β is the latitude of point of puncture, and s is that point of puncture is under day is admittedly Solar hour angle, N is that the maximum of spheric harmonic function launches exponent number,For the naturalization Legendre function on n degree m rank,WithFor spheric harmonic function coefficient, mf is conversion factor.