CN102081157A - Method for testing radar scattering cross section - Google Patents

Abstract

The invention provides a method for testing a radar scattering cross section, which comprises the following steps: 1) selecting and using a laser radar to test a target scattering cross section; 2) listing the definition of the laser radar scattering cross section and the definition of a microwave radar scattering cross section; 3) comparing the definition of the laser radar scattering cross section with the definition of the microwave radar scattering cross section, so as to obtain a relevance expression between the laser radar scattering cross section and the microwave radar scattering cross section; 4) according to the relevance expression, obtaining a transfer equation between the laser radar scattering cross section and the microwave radar scattering cross section; and 5) according to the transfer equation, obtaining a microwave radar scattering cross section curve. According to the invention, the traditional microwave radar is replaced by the laser radar, and the target microwave radar scattering cross section curve can be obtained under the condition of the known frequency scale factor of the laser radar and the microwave radar and the known target laser radar scattering cross section.

Description

The RCS method of testing

Technical field

The invention belongs to the Electro Magnetic Compatibility research field.

Background technology

Because Electromagnetic Scattering of Target characteristic and object construction are closely related, a large amount of design efforts is to finish in the object technology design phase, and targets such as check design effect needs build be shaped after through just learning after the actual measurement, the phenomenon of this design and validity check disconnection has seriously restricted development of technology.

Changing this present situation best bet is to utilize the scale model measuring technology, in the design phase electromagnetic scattering design effect of target is carried out test verification, and the deviser can make amendment to drawing or design again according to test result, till satisfaction.Yet key technical problem that needs to be resolved hurrily of main existence in model measurement: contracting requires testing apparatus to have very high test frequency than principle, this just requires to use the instrument and equipment with very high test frequency, and traditional electromagnetic wave instrument and equipment is difficult to satisfy this high frequency demand.

Summary of the invention

The technical problem to be solved in the present invention is: a kind of new RCS method of testing is provided.

The present invention solves the problems of the technologies described above the technical scheme of being taked to be: the RCS method of testing is characterized in that: it comprises following step:

1) select for use laser radar that target is carried out the scattering cross-section test;

2) list the definition of laser radar scattering cross-section and microwave radar scattering cross-section;

3) two definitions of laser radar scattering cross-section and microwave radar scattering interface are compared, obtain the relevance expression formula of laser radar scattering cross-section and microwave radar scattering cross-section;

4), obtain the transfer equation of laser radar scattering cross-section and microwave radar scattering cross-section according to the relevance expression formula;

5), obtain microwave radar scattering cross-section curve according to transfer equation.

Press such scheme, the target in the described step 1) is the scale model target; The curve of the microwave radar scattering cross-section curve that obtains in the described step 5) for obtaining at the scale model target is according to contracting than principle reduction realistic objective microwave radar scattering cross-section curve.

Press such scheme, described laser radar scattering cross-section definition is:

$\mathrm{\σ}=\underset{R\→\∞}{\lim }4\mathrm{\π}{R}^2\frac{I_r}{I_i}---\left(1\right),$

R is the spacing of target and laser radar, I _rBe the laser energy flux density that receives, I _iBe the emitted laser energy flux density;

Described microwave radar scattering cross-section definition is:

${\mathrm{\&sigma;}}_M=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">R</figure-callout>}}^2\frac{\left|{\mathrm{<figure-callout\; id="2"\; label="E\; r"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">E</figure-callout>}}_r^{}\right|}{\left|{\mathrm{<figure-callout\; id="2"\; label="E\; i"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">E</figure-callout>}}_i^{}\right|}=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">R</figure-callout>}}^2\frac{\left|{\mathrm{<figure-callout\; id="2"\; label="H\; r"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">H</figure-callout>}}_r^{}\right|}{\left|H_i^2\right|}---\left(2\right),$

R is the spacing of target and radar, Er, H _rBe the scatter radar intensity of wave that receives, E _i, H _iTransmitting radar waves intensity for emission.

Press such scheme, described step 2) the relevance expression formula that obtains laser radar scattering cross-section and microwave radar scattering cross-section is:

$\mathrm{\&sigma;}=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{R}^2\frac{I_r}{I_i}\&Proportional;{\mathrm{\&sigma;}}_M=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">R</figure-callout>}}^2\frac{\left|{\mathrm{<figure-callout\; id="2"\; label="E\; r"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">E</figure-callout>}}_r^{}\right|}{\left|{\mathrm{<figure-callout\; id="2"\; label="E\; i"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">E</figure-callout>}}_i^{}\right|}---\left(3\right),$

Or $\mathrm{\&sigma;}=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{R}^2\frac{I_r}{I_i}\&Proportional;{\mathrm{\&sigma;}}_M=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">R</figure-callout>}}^2\frac{\left|{\mathrm{<figure-callout\; id="2"\; label="H\; r"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">H</figure-callout>}}_r^{}\right|}{\left|H_i^2\right|}---\left(4\right),$

According to the relevance expression formula, can obtain | E _r| ²∝ I _rOr | H _r| ²∝ I _r, | E _i| ∝ I _iOr | H _i| ²∝ I _i, the laser radar scattering cross-section is the mould side of the corresponding radio field intensity of energy flux density of laser with the corresponding relation of microwave radar scattering cross-section expression formula.

Press such scheme, the laser radar scattering cross-section that described step 3) obtains and the transfer equation of RCS:

$\mathrm{\&sigma;}=\frac{f_L}{f_R}{\mathrm{\&sigma;}}_M={\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="DEST\_PATH\_HDA0000046165120000012.png"\; state="\{\{state\}\}">M</figure-callout>}}^2{\mathrm{\&sigma;}}_M---\left(5\right),$

F in the formula _RBe the frequency that corresponding radar is worked, fL is the frequency that corresponding laser radar is worked; M ²=f _L/ f _RBe scale-up factor.

Part principle of the present invention is: with the definition comparative analysis of laser radar scattering cross-section and microwave radar scattering cross-section as can be seen, although the mathematic(al) representation form difference of the two, but physical essence is identical in fact, and is main because of the angle from optics, | E _r| ²∝ I _rOr | H _r| ²∝ I _r, | E _i| ∝ I _iOr | H _i| ²∝ I _iIn the RCS test of carrying out target, adopt method of testing to obtain laser radar scattering cross-section σ _MAbsolute value; Then further form the conversion method of the two by the scale-up factor of determining the two.

Beneficial effect of the present invention is:

1, provides a kind of new RCS method of testing, adopt laser radar to substitute the microwave radar of break-through, be easy to satisfy the high frequency requirement owing to the laser radar frequency of operation is very high;

2, solve at present the difficult problem that laser radar scattering cross-section and microwave radar scattering cross-section can't be changed, help the RCS of various target is estimated;

3, under the prerequisite of the frequency proportions coefficient of known laser radar and microwave radar and target laser radar scattering cross-section, can obtain the microwave radar scattering cross-section of target, be convenient to better the electromagnetic scattering design effect of target be carried out test verification in the design phase.

Description of drawings

Fig. 1 is triangular corner reflector and incident synoptic diagram thereof

Fig. 2 is the laser radar scattering cross-section curve of triangular corner reflector

Fig. 3 is the microwave radar scattering cross-section curve of triangular corner reflector

Embodiment

Present embodiment is that example is elaborated with the triangular corner reflector.Model information is as follows: the length of side is 0.1m, and incident direction as shown in Figure 1.Suppose that the microwave radar frequency of operation is 10GHz, the laser radar frequency of operation is 10000GHz.

At first select for use laser radar to carry out radar scattering interface detection (being the RCS test), obtain the laser radar scattering cross-section curve of triangular corner reflector, (for the ease of showing that curve unit has been converted to dB) as shown in Figure 2;

By the frequency of operation of microwave radar and laser radar M as can be known ²=f _L/ f _R=1000;

With M ²In the transfer equation of=1000 substitution laser radar scattering cross-sections and microwave radar scattering cross-section, can calculate the microwave radar scattering cross-section curve of triangular corner reflector under the 10GHz frequency, (for the ease of showing that curve unit has been converted to dB) as shown in Figure 3.

Claims (5)

1. RCS method of testing, it is characterized in that: it comprises following step:

1) select for use laser radar that target is carried out the scattering cross-section test;

2) list the definition of laser radar scattering cross-section and microwave radar scattering cross-section;

3) two definitions of laser radar scattering cross-section and microwave radar scattering interface are compared, obtain the relevance expression formula of laser radar scattering cross-section and microwave radar scattering cross-section;

4), obtain the transfer equation of laser radar scattering cross-section and microwave radar scattering cross-section according to the relevance expression formula;

5), obtain microwave radar scattering cross-section curve according to transfer equation.

2. RCS method of testing according to claim 1 is characterized in that: the target in the described step 1) is the scale model target; The curve of the microwave radar scattering cross-section curve that obtains in the described step 5) for obtaining at the scale model target is according to contracting than principle reduction realistic objective microwave radar scattering cross-section curve.

3. RCS method of testing according to claim 1 and 2 is characterized in that: described laser radar scattering cross-section definition is:

$\mathrm{\&sigma;}=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{R}^2\frac{I_r}{I_i}---\left(1\right),$

R is the spacing of target and laser radar, I _rBe the laser energy flux density that receives, I _iBe the emitted laser energy flux density;

Described microwave radar scattering cross-section definition is:

${\mathrm{\&sigma;}}_M=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{R}^2\frac{\left|E_r^2\right|}{\left|E_i^2\right|}=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{R}^2\frac{\left|H_r^2\right|}{\left|H_i^2\right|}---\left(2\right),$

R is the spacing of target and radar, E _r, H _rBe the scatter radar intensity of wave that receives, E _i, H _iTransmitting radar waves intensity for emission.

4. RCS method of testing according to claim 3 is characterized in that: the relevance expression formula that described step 2) obtains laser radar scattering cross-section and microwave radar scattering cross-section is:

$\mathrm{\&sigma;}=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{R}^2\frac{I_r}{I_i}\&Proportional;{\mathrm{\&sigma;}}_M=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{R}^2\frac{\left|E_r^2\right|}{\left|E_i^2\right|}---\left(3\right),$

Or $\mathrm{\&sigma;}=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{R}^2\frac{I_r}{I_i}\&Proportional;{\mathrm{\&sigma;}}_M=\underset{R\&RightArrow;\&infin;}{\lim }4\mathrm{\&pi;}{R}^2\frac{\left|H_r^2\right|}{\left|H_i^2\right|}---\left(4\right),$

According to the relevance expression formula, can obtain | E _r| ²∝ I _rOr | H _r| ²∝ I _r, | E _i| ∝ I _iOr | H _i| ²∝ I ⁱ, the laser radar scattering cross-section is the mould side of the corresponding radio field intensity of energy flux density of laser with the corresponding relation of microwave radar scattering cross-section expression formula.

5. RCS method of testing according to claim 3 is characterized in that: the laser radar scattering cross-section that described step 3) obtains and the transfer equation of RCS:

$\mathrm{\&sigma;}=\frac{f_L}{f_R}{\mathrm{\&sigma;}}_M=M^2{\mathrm{\&sigma;}}_M---\left(5\right),$

F in the formula _RBe the frequency that corresponding radar is worked, f _LIt is the frequency that corresponding laser radar is worked; M ²=f _L/ f _RBe scale-up factor.

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