CN102411664A - Backscatter-and-oblique-ionograms-based joint inversion method for ionospheric parameters - Google Patents

Abstract

The invention discloses a backscatter-and-oblique-ionograms-based joint inversion method for ionospheric parameters. The method comprises the following steps of: determining an ionospheric model required by the backscatter detection and oblique detection joint inversion as a quasi-parabolic model; setting parameters of the ionospheric model, and calculating by using the set ionospheric parameters to obtain a simulated backscatter ionogram front edge and a simulated oblique ionogram; adding random errors into the simulated backscatter ionogram front edge and the simulated oblique ionogram, wherein the simulated backscatter ionogram front edge and the simulated oblique ionogram into which the random errors are added serve as the backscatter ionogram front edge and the oblique ionogram for the final inversion; and performing data sampling on the backscatter ionogram front edge and the oblique ionogram which are used for the final inversion and comparing the difference between the inversed result and the set parameters of the ionospheric model to judge the effectiveness of a retrieval algorithm, wherein the sampled data serves as the input of the inversion. By introducing the novel ionospheric joint detection technology and taking detection data, in different forms, of the same detection area as the input of the retrieval algorithm, the precision and stability of the inversion are effectively improved.

Description

Based on Returning scattering and the method for tiltedly surveying ionogram joint inversion ionosphere parameter

Technical field

The present invention relates to ionospheric inversion, reconfiguration technique field, relate in particular to a kind of based on Returning scattering and the method for tiltedly surveying ionogram joint inversion ionosphere parameter.

Background technology

Along with the HF radiowave in extensive applications such as broadcasting, communication, radars, also more and more deep to the ionospheric research of HF channel.Ionosphere has in time, space the and therefore characteristic that changes carries out ionospheric probing in real time, understands ionospheric structure, and very important meaning is arranged.A kind of just technology of obtaining the ionosphere state based on the real-time detection data of ionospheric inversion.

In the ionospheric inversion problem, use comparatively general with ionosphere model parameters inverting based on pattern.Based on type method, Chinese scholars utilizes different detection datas to develop multiple ionosphere parameter inversion method.At present, existing inversion method normally carries out based on single kind detection means, and the precision of inverting and stability are difficult to reach requirement.

Summary of the invention

In view of above-mentioned analysis, the present invention aims to provide a kind of based on Returning scattering and the method for tiltedly surveying ionogram joint inversion ionosphere parameter, in order to solve the problems that existing detection method exists.

The object of the invention is mainly realized through following technical scheme:

A kind of based on Returning scattering and the method for tiltedly surveying ionogram joint inversion ionosphere parameter, comprising:

Steps A: confirm Returning scattering is surveyed and the oblique incidence souding joint inversion need be used the ionospheric model parabolic model that is as the criterion;

Step B: set the size of ionosphere model parameters, utilize the ionosphere parameter of setting to calculate the Returning scattering ionogram forward position and the oblique ionogram of surveying of emulation;

Step C: to the Returning scattering ionogram forward position of emulation with tiltedly survey ionogram and add the Returning scattering ionogram forward position used as final inverting after the stochastic error and tiltedly survey ionogram;

Step D: data sampling is carried out as the input of inverting and the region of search of definite ionospheric model with the oblique ionogram of surveying in the Returning scattering ionogram forward position to final inverting is used; The difference that compares the ionosphere model parameters of inversion result and setting, thereby the validity of judgement inversion algorithm.

Wherein, said accurate parabolic model representation does,

Wherein, f _pBe plasma frequency, f _cBe threshold frequency, r _mBe the corresponding height of maximum electron concentration, r _bThe height of bottom, ionosphere, y _m=r _m-r _bFor ionosphere half thick, the plasma frequency f of corresponding r place _pSatisfy following relation with electron concentration N R represent with respect to the earth centre of sphere distance, r ₀Earth radius.

Under accurate parabolic model, the ground distance D between the group path P ' of radio wave propagation and electric wave pick-up point and the launching site can accurate Calculation, and expression formula is following,

$D={2r}_0\{(\mathrm{\&gamma;}-{\mathrm{\&beta;}}_0)-\frac{{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="HSA00000279358500012.png,HSA00000279358500022.png"\; state="\{\{state\}\}">r</figure-callout>}}_0\cos {\mathrm{\&beta;}}_0}{2\sqrt{C}}\ln \frac{B^2-4\mathrm{AC}}{4C{(\sin \mathrm{\&gamma;}+\frac{1}{r_b}\sqrt{C}+\frac{1}{2\sqrt{C}}B)}^2}\}$

$P^{\&prime;}=2\{r_b\sin \mathrm{\&gamma;}-{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="HSA00000279358500012.png,HSA00000279358500022.png"\; state="\{\{state\}\}">r</figure-callout>}}_0\sin {\mathrm{\&beta;}}_0+\frac{1}{A}[-r_b\sin \mathrm{\&gamma;}-\frac{B}{4\sqrt{A}}\ln \frac{B^2-4\mathrm{AC}}{{({2\mathrm{Ar}}_b+B+{2r}_b\sqrt{A}\sin \mathrm{\&gamma;})}^2}\left]\right\};$

Wherein $A=1-\frac{1}{{\mathrm{<figure-callout\; id="2"\; label="F"\; filenames="HSA00000279358500021.png,HSA00000279358500022.png"\; state="\{\{state\}\}">F</figure-callout>}}^2}+{\left(\frac{r_b}{{\mathrm{Fy}}_m}\right)}^2,$ $B=-\frac{{2r}_m{r}_b^2}{F^2{\mathrm{<figure-callout\; id="2"\; label="y\; m"\; filenames="HSA00000279358500021.png,HSA00000279358500022.png"\; state="\{\{state\}\}">y</figure-callout>}}_m^{}},$ $C={\left(\frac{r_b{r}_m}{{\mathrm{Fy}}_m}\right)}^2-{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="HSA00000279358500012.png,HSA00000279358500022.png"\; state="\{\{state\}\}">r</figure-callout>}}_0^2{\mathrm{<figure-callout\; id="2"\; label="Cos"\; filenames="HSA00000279358500021.png,HSA00000279358500022.png"\; state="\{\{state\}\}">Cos</figure-callout>}}^2{\mathrm{\&beta;}}_0,$ $F=f/f_c,$ $\mathrm{Cos}\mathrm{\&gamma;}=\frac{r_0}{r_b}\mathrm{Cos}{\mathrm{\&beta;}}_0,$ γ is the incident angle of ray in the bottom, ionosphere, β ₀The initial elevation angle for ray.

Said step D specifically comprises:

Based on the square error minimum criteria, on the Returning scattering ionogram forward position ionogram that inverting is used, get K ₁Individual observed reading

Oblique survey ionogram in that inverting is used is got K ₂Individual observed reading

The group path that the corresponding ionosphere model parameters by in the region of search of ionospheric model calculates does With

Square error between observed reading and the calculated value does,

${\mathrm{\&epsiv;}}^2=\frac{1}{K_1+K_2}[\underset{i=1}{\overset{K_1}{\mathrm{\&Sigma;}}}{\left(P_{1i}^{\&prime;}{P}_{1i}(\stackrel{\&OverBar;}{\mathrm{\&xi;}},f_i)\right)}^2+{\underset{i=1}{\overset{K_2}{\mathrm{\&Sigma;}}}(P_{2i}^{\&prime;}-P_{2i}(\stackrel{\&OverBar;}{\mathrm{\&xi;}},f_i))}^2]$

Confirm region of search Φ, wherein (f _c, r _b, y _m) ∈ Φ, in region of search, carry out global search and with the f in the region of search _c, r _bAnd y _mNumerical value as input, square error is the ionosphere parameter f in hour corresponding search territory _c, r _bAnd y _mBe optimal value.

Beneficial effect of the present invention is following:

The present invention is through introducing novel ionosphere combined detection technology and utilize the input of the detection data of same search coverage various ways as inversion algorithm, thereby effectively improves inversion accuracy and stability.

Other features and advantages of the present invention will be set forth in specification subsequently, and from specification, becoming apparent of part perhaps understood by embodiment of the present invention.The object of the invention can be realized through the structure that in the instructions of being write, claims and accompanying drawing, is particularly pointed out and obtained with other advantages.

Description of drawings

Fig. 1 is the principle schematic of Returning scattering of the present invention and oblique incidence souding combined detection;

The combined detection ionogram that Fig. 2 obtains through emulation for the present invention;

Fig. 3 is the schematic flow sheet of the method for the invention;

Fig. 4 is the Returning scattering ionogram forward position of emulation among the present invention;

Fig. 5 is the oblique survey ionogram of emulation among the present invention.

Embodiment

The object of the present invention is to provide a kind of based on Returning scattering and the method for tiltedly surveying ionogram joint inversion ionosphere parameter; Through introducing novel ionosphere combined detection technology and utilize of the input of the detection data of same search coverage various ways, thereby effectively improve inversion accuracy and stability as inversion algorithm.

The basic thought of Returning scattering and oblique incidence souding combined detection is; In Returning scattering is surveyed the overlay area, several receiving equipments are set; Returning scattering is surveyed to transmit and is directly received by several receiving equipments in the search coverage, and therefore, transmitter that Returning scattering is surveyed and the receiving equipment in the search coverage can constitute several oblique incidence souding systems; Thereby survey when realizing two kinds of detection modes to the same area, Returning scattering and oblique incidence souding combined detection principle are referring to Fig. 1.This combined detection system can obtain the two kinds of different detection informations of Returning scattering and oblique incidence souding under the same electrical absciss layer state; Be Returning scattering ionogram and the oblique ionogram of surveying; Here provided under the combined detection system; Suppose that 1500 kilometers places of range transmission point are provided with oblique survey receiving equipment in Returning scattering is surveyed areal coverage, obtain the signal of combined detection ionogram like Fig. 2 through emulation.

The method that proposes among the present invention based on Returning scattering and oblique survey ionogram joint inversion ionosphere parameter; Considered subordinate's advantage of this combined detection mode just: two kinds of detection modes carry out simultaneously; The ionosphere state of same time of the same area can be reflected, message complementary sense can be realized.The thought of this joint inversion realizes the accurate inverting to the same area ionosphere parameter through merging two kinds of detection informations.Concrete implementation procedure is: at first need confirm the ionospheric model that uses, utilize Returning scattering that combined detection obtains then and tiltedly survey ionogram, under the square error least meaning, obtain the ionosphere parameter through global optimizing.

Specifically describe the preferred embodiments of the present invention below in conjunction with accompanying drawing, wherein, accompanying drawing constitutes the application's part, and is used to explain principle of the present invention with embodiments of the invention.

As shown in Figure 3, Fig. 3 is the schematic flow sheet of the method for the invention, specifically can comprise the steps:

Step 301: confirm the ionospheric model that Returning scattering is surveyed and the oblique incidence souding joint inversion need be used; Be QP ionospheric model (accurate parabolic ionospheric model);

Step 302: set the size of ionosphere model parameters, utilize the ionosphere parameter of setting to calculate the Returning scattering ionogram forward position and the oblique ionogram of surveying of emulation;

Step 303: to the Returning scattering ionogram forward position of emulation with tiltedly survey ionogram and add the Returning scattering ionogram forward position used as final inverting after the stochastic error and tiltedly survey ionogram;

Step 304: data sampling is carried out as the input of inverting and the region of search of definite ionospheric model with the oblique ionogram of surveying in the Returning scattering ionogram forward position to final inverting is used; The difference that compares the ionosphere model parameters of inversion result and setting, thereby the validity of judgement inversion algorithm.

Specify as follows:

1, problem is an inverse problem, in brief, exactly by fruit ask because of, corresponding with it direct problem be by because of asking really.The corresponding ionospheric radio wave propagation problem of process, the relation between its group path and electron concentration distribution and the frequency can be represented with following general type,

P′(f)＝F(N(r)，f) (1)

The equality left side is corresponding to ionization detection figure, and what result of that probe provided is the relation of group path P ' and frequency of operation f.Expression this group path in equality the right is the function of ionosphere electron concentration distribution N (r) and frequency of operation f, and funtcional relationship is known.Corresponding radio wave propagation direct problem is exactly when electron concentration is known, and we can accurately obtain ionogram with the funtcional relationship on the right is that P ' (f) concerns.The ionospheric inversion problem that we speak of be exactly known P ' (f), utilize

N(r)＝F ^-1(P′(f)，f) (2)

Find the solution electron concentration distribution N (r).Find the solution for ease, we distribute to electron concentration and carry out modeling, promptly are converted into the solving model parameter finding the solution the electron concentration distribution.Below further introduce ionosphere model parameters inverting based on pattern.

2, the ionosphere model parameters inverting of pattern depends on concrete Model Selection; Consider accurate parabolic (QP) ionospheric model can describe the ionosphere electron concentration with the height variation tendency; The analytical expression of ray propagates parameter can be provided again, and in inverting, be widely used.Therefore the model parameter inverting among the present invention is the basis with ionospheric accurate parabolic (QP) model.

Accurate parabolic (QP) model is by Voogt the earliest ^[9]Propose, it is expressed as plasma frequency and distributes,

F wherein _pBe plasma frequency, f _cBe threshold frequency, r _mBe the corresponding height of maximum electron concentration, r _bThe height of bottom, ionosphere, y _m=r _m-r _bFor ionosphere half thick, the plasma frequency f of corresponding r place _pSatisfy following relation with electron concentration N

R represent with respect to the earth centre of sphere distance, r ₀Earth radius.

Under accurate parabolic (QP) model, the ground distance D between the group path P ' of radio wave propagation and electric wave pick-up point and the launching site can accurate Calculation.Croft is at document ^[10]In provided its analytic solution, expression formula is following,

$D={2r}_0\{(\mathrm{\&gamma;}-{\mathrm{\&beta;}}_0)-\frac{{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="HSA00000279358500012.png,HSA00000279358500022.png"\; state="\{\{state\}\}">r</figure-callout>}}_0\cos {\mathrm{\&beta;}}_0}{2\sqrt{C}}\ln \frac{B^2-4\mathrm{AC}}{4C{(\sin \mathrm{\&gamma;}+\frac{1}{r_b}\sqrt{C}+\frac{1}{2\sqrt{C}}B)}^2}\}---\left(4\right)$

$P^{\&prime;}=2\{r_b\sin \mathrm{\&gamma;}-{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="HSA00000279358500012.png,HSA00000279358500022.png"\; state="\{\{state\}\}">r</figure-callout>}}_0\sin {\mathrm{\&beta;}}_0+\frac{1}{A}[-r_b\sin \mathrm{\&gamma;}-\frac{B}{4\sqrt{A}}\ln \frac{B^2-4\mathrm{AC}}{{({2\mathrm{Ar}}_b+B+{2r}_b\sqrt{A}\sin \mathrm{\&gamma;})}^2}\left]\right\}---\left(5\right)$

Wherein $A=1-\frac{1}{{\mathrm{<figure-callout\; id="2"\; label="F"\; filenames="HSA00000279358500021.png,HSA00000279358500022.png"\; state="\{\{state\}\}">F</figure-callout>}}^2}+{\left(\frac{r_b}{{\mathrm{Fy}}_m}\right)}^2,$ $B=-\frac{{2r}_m{r}_b^2}{F^2{\mathrm{<figure-callout\; id="2"\; label="y\; m"\; filenames="HSA00000279358500021.png,HSA00000279358500022.png"\; state="\{\{state\}\}">y</figure-callout>}}_m^{}},$ $C={\left(\frac{r_b{r}_m}{{\mathrm{Fy}}_m}\right)}^2-{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="HSA00000279358500012.png,HSA00000279358500022.png"\; state="\{\{state\}\}">r</figure-callout>}}_0^2{\mathrm{<figure-callout\; id="2"\; label="Cos"\; filenames="HSA00000279358500021.png,HSA00000279358500022.png"\; state="\{\{state\}\}">Cos</figure-callout>}}^2{\mathrm{\&beta;}}_0,$ $F=f/f_c,$ $\mathrm{Cos}\mathrm{\&gamma;}=\frac{r_0}{r_b}\mathrm{Cos}{\mathrm{\&beta;}}_0,$ γ is the incident angle of ray in the bottom, ionosphere, β ₀The initial elevation angle for ray.

3, the present invention adopts the square error minimum criteria to carry out inverting.On the ionogram of Returning scattering ionogram forward position, get K ₁Individual observed reading

Get K at the oblique ionogram of surveying ₂Individual observed reading

The corresponding group path that is calculated by ionosphere model parameters does

With Square error between observed reading and the calculated value does,

${\mathrm{\&epsiv;}}^2=\frac{1}{K_1+K_2}[\underset{i=1}{\overset{K_1}{\mathrm{\&Sigma;}}}{\left(P_{1i}^{\&prime;}{P}_{1i}(\stackrel{\&OverBar;}{\mathrm{\&xi;}},f_i)\right)}^2+{\underset{i=1}{\overset{K_2}{\mathrm{\&Sigma;}}}(P_{2i}^{\&prime;}-P_{2i}(\stackrel{\&OverBar;}{\mathrm{\&xi;}},f_i))}^2]---\left(6\right)$

Wherein

is ionosphere model parameters vector, and the process of inverting is exactly in the region of search of ionospheric model, to find one to make

minimum.

arranged among the present invention

For the ease of saying something, below will the present invention will be described with a concrete instance.

We at first suppose accurate parabolic ionosphere model parameters, (f _c, r _b, r _m)=(6,200,300), cps MHz wherein, parasang km.(1) formula of utilization is carried out the direct problem analysis and is obtained the Returning scattering ionogram forward position (see figure 4) of emulation and tiltedly survey the ionogram (see figure 5), i.e.

and

relation.We are based on these two ionograms and introduce certain stochastic error and carry out the validity that this algorithm is verified in inverting.

The first step of inverting at first will be carried out data sampling to ionogram, and sampled point is used as the input of inverting.Here we have analyzed the different sample mode for Returning scattering and the influence of tiltedly surveying the inverting effect.Table 1 (wherein the first six group data frequency is spaced apart 1MHz, and last group is for 4MHz) has been when having provided the introducing round-off error, the statistics during the different sample mode during Returning scattering inverting.The result shows local ionogram because the very high correlativity between its data causes the instability of inversion result, even if just introduce very little round-off error, each inversion result also can produce very big difference.And the very wide data of frequency of utilization distribution not only can effectively overcome this instability, can reduce the influence of measuring error for inversion result simultaneously.Table 2 has provided based on following four kinds of sampled datas and has carried out the inverting situation: 1. the data of choosing low-frequency range 2-6MHz; Near 2.MUF the low elevation angle of 9-10MHz ray; 3. the high elevation angle of high band 8-10MHz ray; 4. comprehensive first three situation.The result shows and uses the low-frequency range data inversion can obtain stable and r accurately _b, can obtain stable and r accurately and use the corresponding data of high-angle rays to carry out inverting _m, comprehensive utilization first three data utilize promptly that the frequency distribution scope is wide carries out inverting with the tangible data of group path diversity ratio, can improve the stability of inverting, have reduced the influence of error for inversion result simultaneously.

The inverting of QP model parameter finally is to confirm three parameter f _c, r _bAnd y _mBased on the square error minimum criteria, on the ionogram of Returning scattering ionogram forward position, get K ₁Individual observed reading

Get K at the oblique ionogram of surveying ₂Individual observed reading The corresponding group path that is calculated by ionosphere model parameters does

With

Square error between observed reading and the calculated value does,

${\mathrm{\&epsiv;}}^2=\frac{1}{K_1+K_2}[\underset{i=1}{\overset{K_1}{\mathrm{\&Sigma;}}}{\left(P_{1i}^{\&prime;}{P}_{1i}(\stackrel{\&OverBar;}{\mathrm{\&xi;}},f_i)\right)}^2+{\underset{i=1}{\overset{K_2}{\mathrm{\&Sigma;}}}(P_{2i}^{\&prime;}-P_{2i}(\stackrel{\&OverBar;}{\mathrm{\&xi;}},f_i))}^2]---\left(6\right)$

At first confirm the region of search Φ of ionospheric model, wherein (f through prediction or experience _c, r _b, y _m) ∈ Φ.In region of search, carry out global search then and calculate square error, a square error hour corresponding ionosphere parameter is optimum solution.

Quote above-mentioned QP model initial parameter, oblique incidence souding transmitting-receiving two places distance is 1000km.Sample mode: Returning scattering is got K ₁=4, the minimum group path that frequency [4 8 12 16] MHz is corresponding tiltedly measures K ₂=3, frequency [4.0 8.5 9.5] MHz, wherein 8.5MHz is corresponding high-angle rays group path, other is the corresponding group path of low-angle ray.The inverting statistics that table 3 time obtains as input corresponding to " true value ", the corresponding variances sigma of introducing of table 4 _dThe statistics of the data inversion of=20 stochastic error.Above-mentioned inversion result shows, even if under the situation of introducing certain stochastic error, this method remains stable convergence, though each inversion result all can have certain deviation, but still very desirable.

Table 1

Table 2

Table 3

Model parameter	f c	r b	r m
				The hunting zone	[4.0?8.0]	[140?260]	[240?360]
1	6.00075	200.04529	300.06828
				2	6.00081	199.98859	300.11577
3	5.99994	199.81671	299.87102
				4	5.99639	200.28718	299.74335
5	5.99338	200.09106	299.57171
				6	5.99835	199.70318	299.89322
7	5.99767	200.49699	299.88841
				8	6.00163	200.31531	300.14037
9	5.99690	200.39479	299.83731
				10	5.99247	200.54909	299.50895
Average	5.9978	200.1688	299.8638
				Standard deviation	0.0031	0.2855	0.2134

Table 4

Model parameter	f c	r b	r m
				The hunting zone	[4.0?8.0]	[140?260]	[240?360]
1	5.90141	203.61031	294.65314
				2	5.92971	204.85502	295.59035
3	6.04480	198.07566	303.07061
				4	5.95337	204.66921	297.40159
5	5.98929	197.33757	299.87635
				6	6.04134	200.55831	301.20647
7	5.99346	199.59121	298.72784
				8	6.02453	197.80326	301.21519
9	5.98416	199.17417	298.43617
				10	6.06635	203.44017	304.09891
Average	5.9928	200.9115	299.4277
				Standard deviation	0.0532	2.9573	3.0687

The present invention is based on the optimum solution of square error minimum criteria through the ionosphere parameter that the global search method obtains.The method of this global optimizing makes synthetic ionogram and actual measurement ionogram that best coincideing arranged.Can draw as drawing a conclusion through emulation, (error is very little in other words not have error) is through the Returning scattering ionogram or tiltedly survey any ionogram of ionogram and carry out inverting and all can restrain and reach optimum solution under theoretical situation.Yet error is inevitable in the actual measurement ionogram; We simulate this situation through the sampling point that obtains under the theoretical case is introduced error; Discovery the situation of true value can occur obviously departing from based on the inversion result of single ionogram, promptly shows as the instability of separating.Yet under the same error situation, use Returning scattering to survey and to utilize different detection means to revise effective stability of solution of improving each other really with the oblique incidence souding joint inversion.

In sum, the invention provides a kind of method based on Returning scattering and oblique survey ionogram joint inversion ionosphere parameter, two kinds of detection modes carry out simultaneously, can reflect the ionosphere state of same time of the same area, can realize message complementary sense.The thought of this joint inversion realizes the accurate inverting to the same area ionosphere parameter through merging two kinds of detection informations.

The above; Be merely the preferable embodiment of the present invention, but protection scope of the present invention is not limited thereto, any technician who is familiar with the present technique field is in the technical scope that the present invention discloses; The variation that can expect easily or replacement all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection domain of claims.

Claims (3)

1. the method based on Returning scattering and oblique survey ionogram joint inversion ionosphere parameter is characterized in that, comprising:

Steps A: confirm Returning scattering is surveyed and the oblique incidence souding joint inversion need be used the ionospheric model parabolic model that is as the criterion;

Step B: set the size of ionosphere model parameters, utilize the ionosphere parameter of setting to calculate the Returning scattering ionogram forward position and the oblique ionogram of surveying of emulation;

Step C: to the Returning scattering ionogram forward position of emulation with tiltedly survey ionogram and add the Returning scattering ionogram forward position used as final inverting after the stochastic error and tiltedly survey ionogram;

Step D: data sampling is carried out as the input of inverting and the region of search of definite ionospheric model with the oblique ionogram of surveying in the Returning scattering ionogram forward position to final inverting is used; The difference that compares the ionosphere model parameters of inversion result and setting, thereby the validity of judgement inversion algorithm.

2. method according to claim 1 is characterized in that, said accurate parabolic model representation does,

Wherein, f _pBe plasma frequency, f _cBe threshold frequency, r _mBe the corresponding height of maximum electron concentration, r _bThe height of bottom, ionosphere, y _m=r _m-r _bFor ionosphere half thick, the plasma frequency f of corresponding r place _pSatisfy following relation with electron concentration N

R represent with respect to the earth centre of sphere distance, r ₀Earth radius.

Under accurate parabolic model, the ground distance D between the group path P ' of radio wave propagation and electric wave pick-up point and the launching site can accurate Calculation, and expression formula is following,

$D={2r}_0\{(\mathrm{\&gamma;}-{\mathrm{\&beta;}}_0)-\frac{r_0\cos {\mathrm{\&beta;}}_0}{2\sqrt{C}}\ln \frac{B^2-4\mathrm{AC}}{4C{(\sin \mathrm{\&gamma;}+\frac{1}{r_b}\sqrt{C}+\frac{1}{2\sqrt{C}}B)}^2}\}$

$P^{\&prime;}=2\{r_b\sin \mathrm{\&gamma;}-r_0\sin {\mathrm{\&beta;}}_0+\frac{1}{A}[-r_b\sin \mathrm{\&gamma;}-\frac{B}{4\sqrt{A}}\ln \frac{B^2-4\mathrm{AC}}{{({2\mathrm{Ar}}_b+B+{2r}_b\sqrt{A}\sin \mathrm{\&gamma;})}^2}\left]\right\};$

Wherein $A=1-\frac{1}{F^2}+{\left(\frac{r_b}{{\mathrm{Fy}}_m}\right)}^2,$ $B=-\frac{{2r}_m{r}_b^2}{F^2{y}_m^2},$ $C={\left(\frac{r_b{r}_m}{{\mathrm{Fy}}_m}\right)}^2-r_0^2{\mathrm{Cos}}^2{\mathrm{\&beta;}}_0,$ $F=f/f_c,$ $\mathrm{Cos}\mathrm{\&gamma;}=\frac{r_0}{r_b}\mathrm{Cos}{\mathrm{\&beta;}}_0,$ γ is the incident angle of ray in the bottom, ionosphere, β ₀The initial elevation angle for ray.

3. method according to claim 2 is characterized in that, said step D specifically comprises:

Based on the square error minimum criteria, on the Returning scattering ionogram forward position ionogram that inverting is used, get K ₁Individual observed reading

Oblique survey ionogram in that inverting is used is got K ₂Individual observed reading

The group path that the corresponding ionosphere model parameters by in the region of search of ionospheric model calculates does

With Square error between observed reading and the calculated value does,

${\mathrm{\&epsiv;}}^2=\frac{1}{K_1+K_2}[\underset{i=1}{\overset{K_1}{\mathrm{\&Sigma;}}}{\left(P_{1i}^{\&prime;}{P}_{1i}(\stackrel{\&OverBar;}{\mathrm{\&xi;}},f_i)\right)}^2+{\underset{i=1}{\overset{K_2}{\mathrm{\&Sigma;}}}(P_{2i}^{\&prime;}-P_{2i}(\stackrel{\&OverBar;}{\mathrm{\&xi;}},f_i))}^2]$

Confirm region of search Φ, wherein (f _c, r _b, y _m) ∈ Φ, in region of search, carry out global search and with the f in the region of search _c, r _bAnd y _mNumerical value as input, square error is the ionosphere parameter f in hour corresponding search territory _c, r _bAnd y _mBe optimal value.

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