CN102944868B - Low-radar cross section metal rack and design method thereof - Google Patents

Abstract

The invention provides a low-radar cross section metal rack and a design method thereof. The method comprises the steps of selecting a plurality of cross sections to be designed on the metal rack; designing all cross sections respectively, wherein a dimension range of cross sections is calculated and is determined according to dimensions of long shafts of cross sections and dimensions of short shaftsof cross sections; adopting a specific formula, and selecting a group of different values for shape control factors in the specific formula to obtain a group of contour line expressions of cross sections, wherein the specific formula is defined in the description, -L<=x<=0, H represents short half-shafts, L represents long half-shafts, mu represents shape control factors of cross sections, mu>0, x represents horizontal coordinates of contour lines of cross sections, and y represents longitudinal coordinates of contour lines of cross sections; selecting one contour line expression from the group of contour line expressions of cross sections to serve as the specific contour line expression, and using the specific contour line expression for designing cross sections; and uniformly connecting all cross sections according to the height and the slant angle of the metal rack to obtain the shape of the metal rack.

Description

Low radar scattering cross section metal support and method for designing thereof

Technical field

The present invention relates to the communication technology, relate in particular to a kind of low radar scattering cross section metal support and method for designing thereof.

Background technology

(Radar Cross-Section, hereinafter to be referred as the RCS) configuration design of target low radar scattering cross section and Material-stealth technology are two main gordian techniquies of modern Stealthy Target design.In design, development and the process of the test of modern Stealthy Target, need to carry out static RCS or Dynamic RCS measurement to target scaled model and full-scale target, so that the RCS of designed target is carried out to diagnostic measures and assessment, for the design and the Stealth Fighter assessment that improve target provide reference frame.Wherein, the static rcs measurement of target scaled model and full-scale target is topmost technological approaches.

In order to complete the high-acruracy survey to Stealthy Target, RCS checkout area adopts metal support to support target mostly, and this support need to be by special Geometrical molding and processing and manufacturing, so that the RCS level of support is significantly lower than the RCS level of surveyed target, thereby reach the object of accurate measurement target RCS.Due to the RCS level of metal support depend primarily on metal support forward position seamed edge in split angle and pitch angle, inside split that angle is less or pitch angle is larger, the low RCS performance of metal support is better.For the metal support of specific occasion, pitch angle is certain, general, need improve by splitting angle in changing the low RCS performance of metal support.Therefore, in metal support design, need be under the condition that meets load-bearing, reduce as much as possible to split in it angle.

In prior art, metal support has following three kinds: wherein, the xsect of the first metal support consists of single-curvature circular arc; The xsect of the second metal support consists of hyperbolicity circular arc; The third xsect that is metal support consists of cosine function curve.In prior art, design by the following method metal support: according to the load bearing requirements of metal support and support cross sectional dimensions, by adjusting axial ratio parameter, the low RCS performance of metal support is met the demands, thereby make load bearing requirements, support cross sectional dimensions and the low RCS performance three balance of metal support.

At least there is following problem in prior art: first two method for designing is all difficult to adopt simple analytic expression by the automatic complete design of computing machine; And because adjustable parameter is few, the degree of freedom of these three kinds of methods in actual design process is very little, be difficult to find equilibrium point between the low RCS performance of support load-bearing, support sectional dimension and support, in design, there is great difficulty.In addition, due to the raising that at present the accurate measurement to RCS level requires, the low RCS characteristic of metal support is had higher requirement, this also makes also must to adopt metal support that existing method for designing obtains can not meet the test request of Stealthy Target.

Summary of the invention

The invention provides a kind of low radar scattering cross section metal support and method for designing thereof for radar target test, in order to optimize the structure of existing metal support.

First aspect of the present invention is to provide a kind of low radar scattering cross section metal support method for designing, comprising:

Several xsects to be designed on selected described metal support;

Each described xsect is adopted respectively to following step design:

Calculate the range of size of described xsect, wherein, the range of size of described xsect is determined by the size of xsect major axis and the size of minor axis;

Adopt specific formulation, and the shape controlling elements in described specific formulation are got to one group of mutually different value, to obtain one group of outline line expression formula of described xsect, wherein, described specific formulation is

-L≤x≤0, wherein, H is minor semi-axis; L is major semi-axis; μ is the shape controlling elements of xsect, μ >0, and x is the horizontal ordinate of described cross-sectional profiles line; Y is the ordinate of described cross-sectional profiles line;

According to low RCS predictor formula, from one group of outline line expression formula of described xsect, select an outline line expression formula, using as particular wheel profile expression formula, and for the design of xsect;

According to the height of described metal support and pitch angle, evenly connect xsect described in each, to obtain the profile of described metal support.

Method as above, preferably, described according to low RCS predictor formula, described in obtain the profile of described metal support after, also comprise:

Adopt method of moment or the progressive technology of high frequency, to obtain the corresponding relation between low RCS and the frequency of described metal support.

Method as above, preferably, selected xsect quantity to be designed is two, is respectively upper xsect and the lower xsect of described metal support.

Another aspect of the present invention is to provide a kind of low radar scattering cross section metal support, and wherein, the cross-sectional profiles line of described metal support meets following specific formulation:

-L≤x≤0, wherein, H is minor semi-axis; L is major semi-axis; μ is the shape controlling elements of xsect, μ >0, and x is the horizontal ordinate of described cross-sectional profiles line; Y is the ordinate of described cross-sectional profiles line.

Low radar scattering cross section metal support provided by the invention and method for designing thereof, the adjustable parameter of metal support cross-sectional profiles line function expression formula is increased to three, and by changing the value of shape controlling elements in formula, can select to meet the support xsect of low RCS level, and all xsects are connected smoothly, be met the metal support of requirement.The method makes the design of metal support between the low RCS performance of support load-bearing, support sectional dimension and support, to find equilibrium point, has met the test request of modern Stealthy Target.

Accompanying drawing explanation

Fig. 1 is the process flow diagram of the low RCS metal support method for designing of the embodiment of the present invention one;

Fig. 2 is the particular flow sheet of step 120 in Fig. 1;

Fig. 3 is the curve map that the outline line of low RCS metal support changes with shape controlling elements;

The process flow diagram of the low RCS metal support method for designing that Fig. 4 provides for the embodiment of the present invention two;

Fig. 5 is the cross-sectional shape under canonical parameter;

Fig. 6 is that under different frequency, any faceted physical optics reflects with incident angle variation characteristic;

Fig. 7 is the local incident angle variation characteristic that difformity factor pair is answered;

Fig. 8 is the shape of the metal support xsect that designed;

Fig. 9 is low RCS metal support design outline design diagram.

Embodiment

Fig. 1 is the process flow diagram of the low RCS metal support method for designing of the embodiment of the present invention one, and Fig. 2 is the particular flow sheet of step 120 in Fig. 1.As depicted in figs. 1 and 2, the method for the present embodiment comprises:

Step 110: several xsects to be designed on selected metal support.

In this step, particularly, when a metal support is designed, first need to determine xsect to be designed.For the consistent support of upper lower section, only need to design an xsect; And for the different support of upper lower section, needing at least two of designs, even more xsects, in the end to connect by these multiple xsects the profile that obtains whole support.

Step 120: each xsect is designed respectively.

Particularly, after selected several xsects to be designed, just can design respectively each xsect, and the design of each xsect can adopt identical method.As shown in Figure 2, to the concrete steps of each xsect design, can comprise:

Step 121: the range of size that calculates xsect.

Particularly, because the range of size of xsect is determined by the size of xsect major axis and the size of minor axis, therefore, according to metal support load-bearing, highly, turn the basic demands such as top angle of pitch scope, by the calculating such as mechanically stressed grade of necessity, first definite support is chosen major axis dimension and the minor axis dimension of each xsect of design, and the height of definite support and pitch angle.It should be noted that, the calculating at cross sectional dimensions scope and metal support height and pitch angle can adopt existing techniques in realizing.

Calculate after the range of size of xsect, can learn major axis and the minor axis of xsect.Herein take metal support towards the one side of radar as " front ", the one side that deviates from radar is " afterwards ".The major axis of xsect is front end major semi-axis and rear end major semi-axis sum, and the minor axis of xsect is front end minor semi-axis and rear end minor semi-axis sum.

Step 122: adopt specific formulation, obtain one group of outline line expression formula of xsect.

Particularly, on definite major axis dimension of each xsect and the basis of minor axis dimension, adopt specific formulation, and the shape controlling elements in specific formulation are got to one group of mutually different value, to obtain one group of outline line expression formula of xsect.Particularly, this specific formulation is:

$y\left(x\right)=\&PlusMinus;\frac{\mathrm{<figure-callout\; id="2"\; label="H"\; filenames="HDA00002459112900032.png"\; state="\{\{state\}\}">H</figure-callout>}}{2^{\mathrm{\&mu;}}}{[1+\cos \left(\frac{x}{L}\mathrm{\&pi;}\right)]}^{\mathrm{\&mu;}},$ -L≤x≤0 (1)

Wherein, H is cross section minor semi-axis, and L is major semi-axis, the shape controlling elements that μ is xsect, and μ >0, x is the horizontal ordinate of cross-sectional profiles line; Y is the ordinate of cross-sectional profiles line.In actual design, the front end cross section contour of metal support xsect and rear end cross section contour be design separately, then two sections of cross section contours is pieced together to the outline line that forms metal support xsect.According to above-mentioned formula (1), can obtain respectively the cross section contour expression formula of the front-end and back-end of xsect.It should be noted that, the shape controlling elements of front end cross section contour and rear end cross section contour can be got identical value, also can get different values.

Particularly, when calculating the size of xsect, the major axis dimension of xsect and minor axis dimension are all definite, now, the value of shape-adjustable controlling elements μ, and μ is got to a different set of value, can obtain one group of outline line expression formula of xsect, the corresponding outline line profile of each outline line expression formula is not quite similar, and also can calculate each outline line expression formula split angle in corresponding by each outline line expression formula.Particularly, in the expression formula of each outline line, x is the horizontal ordinate of cross-sectional profiles line; Y is the ordinate of cross-sectional profiles line.For example, if the major semi-axis of certain xsect and minor semi-axis value are respectively L=400mm and H=100mm, when to μ value 0.2 and 0.4, can obtain the expression formula of corresponding cross-sectional profiles line, be respectively:

$y\left(x\right)=\&PlusMinus;\frac{100}{2^{0.2}}{[1+\cos \left(\frac{x}{400}\mathrm{\&pi;}\right)]}^{0.2},$ -400≤x≤0 (2)

With

$y\left(x\right)=\&PlusMinus;\frac{100}{2^{0.4}}{[1+\cos \left(\frac{x}{400}\mathrm{\&pi;}\right)]}^{0.4},$ -400≤x≤0 (3)

Step 123: select an outline line expression formula for xsect design.Particularly, can be according to the predictor formula of low RCS, as the high-frequency asymptote theory of electromagnetic scattering, apart from RCS computing techniques such as amount methods, the RCS characteristic of the cross-sectional shape that each outline line expression formula is obtained is carried out entry evaluation, and therefrom select RCS level can meet the outline line expression formula of the exterior cross-section of technical requirement, using as particular wheel profile expression formula, and for the design of xsect.Preferably, this low RCS predictor formula can be the high-frequency asymptote theory of electromagnetic scattering.

Step 130: evenly connect each xsect, obtain the profile of metal support.Particularly, after each selected xsect is designed respectively and completed, according to the height of metal support and pitch angle, evenly connect each xsect, obtain the profile of metal support, and the metal support obtaining can meet the requirement of low RCS level.

Above-mentioned low RCS metal support method for designing, the adjustable parameter of metal support cross-sectional profiles line function expression formula is increased to three, and by changing the value of shape controlling elements in formula, can select to meet the support xsect of low RCS level, and all xsects are connected smoothly, be met the metal support of requirement.The method makes the design of support between the low RCS performance of support load-bearing, support sectional dimension and support, to find equilibrium point, has met the test request of modern Stealthy Target.

Fig. 3 is the curve map that the outline line of low RCS metal support changes with shape controlling elements, and particularly, while being given xsect major semi-axis and minor semi-axis, shape controlling elements are got different values.

Particularly, in the case of the major axis of metal support xsect and minor axis dimension definite, for making the shape of metal support meet the requirement of low RCS level, will get different values to μ, with the shape of adjusting pole xsect, to meet under the prerequisite of support load-bearing requirement, therefrom select a shape that RCS level is minimum, thereby it is minimum to realize the final impact of the rcs measurement on target.

As shown in Figure 3, when given xsect major axis and minor axis, when shape controlling elements μ gets different value, can obtain different curve shapes.Wherein, dotted line, dot-and-dash line and dotted line show respectively form factor and are respectively μ and get 0.4,0.6 and the curve shape of 0.8 o'clock, and as comparison, solid line shows the outside drawing that in prior art, hyperbolicity arc section forms, and is labeled as Circular arc.As seen from Figure 3, utilize formula (1), by change major cross-sectional axis, minor axis and 3 parameters of form factor, thereby when given axial ratio, still can arbitrarily control object basic geometric shape and in split angle.

The low RCS metal support method for designing of the embodiment of the present invention, by changing the value of shape controlling elements in metal support cross-sectional profiles line formula, can obtain different geometric shapes and in split the pattern curve at angle, and can therefrom select to meet the support xsect of low RCS level, and finally make the support obtaining find equilibrium point between load-bearing, sectional dimension and low RCS performance, met the test request of modern Stealthy Target.

The process flow diagram of the low RCS metal support method for designing that Fig. 4 provides for the embodiment of the present invention two.As shown in Figure 4, on the basis of above-described embodiment, the metal support method for designing of the present embodiment, after step 130, also comprises:

Step 140: the geometric shape of support is carried out to RCS checking.

The support geometric shape that particularly, can adopt method of moment or high-frequency asymptote technology to obtain the corresponding shape of cross section of particular wheel profile expression formula is verified.Concrete, after the cross-sectional shape due to the RCS level estimating and select to meet the demands, can not determine that how much contoured cradles that obtained by its design meet all technical requirement surely with regard to one.Therefore, in the cross section that each is met the demands, be connected smoothly, obtain after the geometric shape of support, also needing to adopt method of moment or high-frequency asymptote technology etc. to carry out RCS estimates, RCS radar to designed contoured cradle calculates with frequency variation characteristics etc., to verify that designed metal support RCS level meets technical requirement.

If result of calculation shows this metal support design and meets technical requirement, complete design; Otherwise the value of shape-adjustable controlling elements μ, re-starts design and optimizes.

On the basis of above-described embodiment, in the metal support method for designing of the embodiment of the present invention, selected xsect quantity to be designed is two, is respectively upper xsect and the lower xsect of metal support.

Particularly, the lower cross-sectional area of this metal support can be greater than cross-sectional area, to well target is supported; And all according to formula (1), design obtains this upper and lower xsect, and the customized parameter in the cross-sectional profiles line expression formula of the two can be selected unanimously, also can be inconsistent.According to the upper xsect setting and lower xsect, by corresponding two cross sections, be connected, smooth transition, can obtain the metal support that need to design.

Below provide a complete design process that meets the metal support of low RCS level, so that this metal support is met: when radar is observed from support forward position, metal support has good low RCS characteristic.

First, according to the load-bearing of support, highly, the technical requirement such as mechanically stressed, determine that height overall when metal support is holded up is H ₀, inclination angle [theta] ₀; Upper section minor axis is 2H _μ, starting section and rear major cross-sectional axis are respectively L _ufand L _ub, overall length L _uf+ L _ub; Lower section minor axis is 2H _l, starting section and rear major cross-sectional axis are respectively L _lfand L _lb, overall length L _lf+ L _lb.

Secondly, carry out the structure of upper and lower cross-sectional shape.

First utilize formula (1), the profile in design upper, lower horizontal cross section, is optimized design by adjustable shape controlling elements.For lower section and lower section, still adopt the separately design of front end outline line and rear end outline line, utilize the equation of the definite 2 sections of bent arcs of upper xsect of formula (1) to be expressed as:

The expression formula of upper cross-sectional front end outline line is:

$y\left(x\right)=\&PlusMinus;\frac{{\mathrm{<figure-callout\; id="2"\; label="H\; u"\; filenames="HDA00002459112900032.png"\; state="\{\{state\}\}">H</figure-callout>}}_u}{2^{{\mathrm{\&mu;}}_1}}{[1+\cos \left(\frac{x}{L_{\mathrm{uf}}}\mathrm{\&pi;}\right)]}^{{\mathrm{\&mu;}}_1},$ -L _uf≤x≤0 (4)

The expression formula of upper xsect rear end outline line is:

$y\left(x\right)=\&PlusMinus;\frac{{\mathrm{<figure-callout\; id="2"\; label="H\; u"\; filenames="HDA00002459112900032.png"\; state="\{\{state\}\}">H</figure-callout>}}_u}{2^{{\mathrm{\&mu;}}_2}}{[1+\cos \left(\frac{x}{L_{\mathrm{ub}}}\mathrm{\&pi;}\right)]}^{{\mathrm{\&mu;}}_2},$ 0≤x≤L _ub (5)

By formula (4) and (5), can be connected to form the olive shape cross section with the difformity factor.Similarly, can build the geometric shape equation of xsect under support:

The expression formula of lower cross-sectional front end outline line is:

$y\left(x\right)=\&PlusMinus;\frac{{\mathrm{<figure-callout\; id="2"\; label="H\; l"\; filenames="HDA00002459112900032.png"\; state="\{\{state\}\}">H</figure-callout>}}_l}{2^{{\mathrm{\&mu;}}_3}}{[1+\cos \left(\frac{x}{L_{\mathrm{lf}}}\mathrm{\&pi;}\right)]}^{{\mathrm{\&mu;}}_3},$ -L _lf≤x≤0 (6)

The expression formula of lower xsect rear end outline line is:

$y\left(x\right)=\&PlusMinus;\frac{{\mathrm{<figure-callout\; id="2"\; label="H\; l"\; filenames="HDA00002459112900032.png"\; state="\{\{state\}\}">H</figure-callout>}}_l}{2^{{\mathrm{\&mu;}}_4}}{[1+\cos \left(\frac{x}{L_{\mathrm{lb}}}\mathrm{\&pi;}\right)]}^{{\mathrm{\&mu;}}_4},$ 0≤x≤L _lb

(7)

Like this, by adjustable shape controlling elements μ ₁... μ ₄, can regulate the profile in upper, lower horizontal cross section.Fig. 5 is the cross-sectional shape under canonical parameter.As shown in Figure 5, in figure, provided form factor μ get 0.4,0.6 and 0.8 3 kind of situation under curve shape, respectively as shown in dotted line, dot-and-dash line and dotted line.As comparison, in Fig. 5, solid line is the olive shape cross sectional shape being formed by hyperbolicity circular arc, is labeled as Circular arc.As seen from Figure 5, by formula (1), not only can design and there is " concave surface " profile of splitting angle in very little as simple cosine function cross section, also can design " convex surface " profile that there is imperial palace more and split angle than circular curve cross section; And various parameter combinations, just can build and there is the cross-sectional shape of splitting angle in Nei Pi angle, different forward position and rear edge.

Secondly, carry out the optimal design of shape controlling elements.

Obtaining after one group of appearance profile expression formula of support xsect, according to the fundamental relation of electromagnetic scattering mechanism jljl body profile, can determine the form factor μ of the bent arc in front and back end, upper, lower horizontal cross section ₁... μ ₄.Because the optimization method of upper and lower cross sectional shape controlling elements is consistent with effect, below only with regard to the shape controlling elements μ of upper section ₁and μ ₂optimization describe.

The backward electromagnetic scattering in the cross section of oliva shown in Fig. 5 mainly can comprise following 3 kinds: the reflection of the physical optics of oliva curved surface, nose cone are to the impact of diffraction and the surface wave on pinnacle.Below by reducing or eliminating the optimization that realizes support xsect three kinds of impacts.

(a) reduce the configuration design that physical optics reflects

Fig. 6 is that under different frequency, any faceted physical optics reflects with incident angle variation characteristic.As shown in Figure 6, because the physical optics of arbitrarily small planar chip reflects the variation with incident angle, its normalization RCS level is also different.In order to reduce olivary physical optics reflection as far as possible, according to the requirement of the working frequency range of radar and minimum RCS level, requirement is in radar incident direction, on body surface, the local incident angle of any point is all less than 20 °～30 °, more than now can guaranteeing the surperficial low 30～40dB of physical optics reflectance mirror-reflection.Particularly, the tangent line that this local incident angle is any point on body surface and the angle of radar incident direction.

Known by analysis, at the local incidence angle θ (x) of optional position, body surface place, can be expressed as

$\mathrm{\&theta;}\left(x\right)=\underset{\mathrm{\&Delta;x}\&RightArrow;0}{\lim }{\tan }^{-1}\left(\frac{\mathrm{\&Delta;y}}{\mathrm{\&Delta;x}}\right)={\tan }^{-1}\left[y^{\&prime;}\left(x\right)\right]---\left(8\right)$

Wherein, x is the coordinate of radar incident direction, and y is and the coordinate of radar incident direction vertical direction.For low RCS design, require θ (x) <<1, therefore there is tan θ (x) ≈ θ (x).Therefore, (x)=y ' (x) for θ.According to formula (1), have

$\mathrm{\&theta;}\left(x\right)\&ap;\frac{\mathrm{\&mu;}\&CenterDot;\mathrm{\&pi;}}{2^{\mathrm{\&mu;}}}\&CenterDot;\frac{H}{L}\&CenterDot;\frac{\sin \left(\frac{-x}{L}\mathrm{\&pi;}\right)}{{[1+\cos \left(\frac{x}{L}\mathrm{\&pi;}\right)]}^{1-\mathrm{\&mu;}}}---\left(9\right)$

Fig. 7 is the local incident angle variation characteristic that difformity factor pair is answered.As shown in Figure 7, it is 0.4,0.6 and the local incident angle change curve of 0.8 o'clock that dotted line, dot-and-dash line and dotted line are respectively form factor μ, and solid line is the local incident angle change curve that hyperbolicity arc section is corresponding, is labeled as Circular arc.Wherein, object reference center is to be the position of 0 degree with radar incident direction angle.Generally, radar is from the nose cone of the front end of metal support to observing, the incident direction of radar just to the front end nose cone of metal support to.Object reference center can be the place, pinnacle of the front end of metal support herein.As seen from Figure 7, form factor value is less, and its maximum local angle of incidence values is larger.

Because physical optics scattering only results from the light area of radar to body surface, known according to radar observation geometric relationship, for oliva cross-sectional shape, Jin Qi leading section branch produces physical optics scattering, and rear end is in radar shadow district, can not produce physical optics reflection.Therefore, only need when design oliva front end, consider the inhibition to physical optics reflection, be also that the selected form factor of front end of metal support xsect should not be too little.In this example, work as μ ₁be greater than at 0.5 o'clock, its surface is all less than the local incident angle of circular cross-section with the local incident angle between radar.

(b) parameter that reduces pinnacle diffraction is selected and configuration design

Because oliva cross section exists former and later two pinnacles, these two pinnacles are split with rear edge and are split corresponding to the forward position of metal support.Generally only have the wedge diffraction of radar visible range just the back scattering of support to be had to remarkable contribution, therefore, in the present embodiment, only need to consider the diffraction problems of forward position wedge.

From Electromagnetic Scattering Theory, pinnacle or the wedge angle of circular cone and oliva one class body are larger, and its backward scattered field is stronger.Therefore, when carrying out the design of low RCS metal support, should reduce as far as possible support front end in split angle, also reduce the angle, front end pinnacle in upper, lower horizontal cross section.

For the cross-sectional profiles line function expression formula being obtained by formula (1), when form factor μ is wherein close to 1 time, the pinnacle corner connection of the curved profile obtaining is bordering on 0 °.Therefore,, in order to reduce the impact of pinnacle diffraction, form factor should be exhausted may be close to 1.

(c) suppress the configuration design that surface wave affects

Surface wave generally can comprise row ripple and Creeping Wave.For the metal support in olive shape cross section, because its rear end is shadow region to radar, therefore only there is the impact of Creeping Wave.

According to Electromagnetic Scattering Theory, along discontinuous place, contribute to suppress Creeping Wave and walk around rear surface and propagate afterwards, meanwhile, in rear edge, split angle hour, also less at the surface wave reflection coefficient of Hou Yanchu; And in the situation that other conditions are all identical, corresponding RCS is higher for low frequency.Therefore, if emphasize the low frequency performance of support, can suitably increase the shape controlling elements of rear end, relatively to reduce RCS; If emphasize the bearing capacity of support, can reduce shape controlling elements, to increase the cross-sectional area of support, increase bearing capacity.

Then, complete the design of low RCS metal support xsect.

Fig. 8 is the shape of the metal support xsect that designed.As shown in Figure 8, wherein, L ₁=600mm, L ₂=400mm, H=110mm, μ ₁=0.8, μ ₂=0.4.According to same method, can design the each parameter that obtains lower xsect.Because front-end and back-end size and the form factor in upper and lower olive shape cross section all can independently be selected and control, this has brought great degree of freedom to low RCS metal support design.

Finally, by height overall, the inclination angle of metal support, and the parameters of upper and lower xsect obtains the configuration design of low RCS metal support.Fig. 9 is low RCS metal support design outline design diagram.As shown in Figure 9, wherein, metal support height overall is H ₀, inclination angle [theta] ₀; Upper section minor axis 2H _μ, starting section and rear major cross-sectional axis L _ufand L _ub, overall length L _uf+ L _ub, shape controlling elements μ ₁, μ ₂; Lower section minor axis 2H _l, starting section and rear major cross-sectional axis L _lfand L _lb, overall length L _lf+ L _lb, shape controlling elements μ ₃, μ ₄, each parameter Joint Designing obtains the profile of low RCS metal support.

The low RCS metal support method for designing of the embodiment of the present invention, by the adjusting to the upper and lower cross-sectional profiles line function of metal support expression argument, can select to meet the support xsect of low RCS level, and upper and lower cross-section smooth is connected, be met the metal support of requirement.The method makes the design of support between the low RCS performance of support load-bearing, support sectional dimension and support, to find equilibrium point, has met the test request of modern Stealthy Target.

The embodiment of the present invention three provides a kind of low RCS metal support, and the cross-sectional profiles line of metal support meets following function expression:

$y\left(x\right)=\&PlusMinus;\frac{\mathrm{<figure-callout\; id="2"\; label="H"\; filenames="HDA00002459112900032.png"\; state="\{\{state\}\}">H</figure-callout>}}{2^{\mathrm{\&mu;}}}{[1+\cos \left(\frac{x}{L}\mathrm{\&pi;}\right)]}^{\mathrm{\&mu;}},$ -L≤x≤0 (10)

Wherein, be H minor semi-axis, L is major semi-axis, the shape controlling elements that μ is xsect, μ >0, x is the horizontal ordinate of cross-sectional profiles line, y is the ordinate of cross-sectional profiles line.

Particularly, the method for designing that cross-sectional profiles line meets the metal support of above-mentioned formula can, referring to the description of other embodiment in literary composition, repeat no more herein.

The low RCS metal support that the embodiment of the present invention provides, by the adjusting to the upper and lower cross-sectional profiles line function of metal support expression argument, can select to meet the support xsect of low RCS level, and finally make the support obtaining find equilibrium point between load-bearing, sectional dimension and low RCS performance, met the test request of modern Stealthy Target.

One of ordinary skill in the art will appreciate that: all or part of step that realizes above-mentioned each embodiment of the method can complete by the relevant hardware of programmed instruction.Aforesaid program can be stored in a computer read/write memory medium.This program, when carrying out, is carried out the step that comprises above-mentioned each embodiment of the method; And aforesaid storage medium comprises: various media that can be program code stored such as ROM, RAM, magnetic disc or CDs.

Finally it should be noted that: above each embodiment, only in order to technical scheme of the present invention to be described, is not intended to limit; Although the present invention is had been described in detail with reference to aforementioned each embodiment, those of ordinary skill in the art is to be understood that: its technical scheme that still can record aforementioned each embodiment is modified, or some or all of technical characterictic is wherein equal to replacement; And these modifications or replacement do not make the essence of appropriate technical solution depart from the scope of various embodiments of the present invention technical scheme.

Claims (4)

1. a low radar scattering cross section metal support method for designing, is characterized in that, comprising:

Several xsects to be designed on selected described metal support;

Each described xsect is adopted respectively to following step design:

Calculate the range of size of described xsect, wherein, the range of size of described xsect is determined by the size of xsect major axis and the size of minor axis;

Adopt specific formulation, and the shape controlling elements in described specific formulation are got to one group of mutually different value, to obtain one group of outline line expression formula of described xsect, wherein, described specific formulation is -L≤x≤0, wherein, H is minor semi-axis; L is major semi-axis; μ is the shape controlling elements of xsect, μ >0, and x is the horizontal ordinate of described cross-sectional profiles line; Y is the ordinate of described cross-sectional profiles line;

According to high-frequency asymptote technology or the method for moment of electromagnetic scattering, the RCS of the cross-sectional shape that each outline line expression formula is obtained carries out entry evaluation, from one group of outline line expression formula of described xsect, select an outline line expression formula, using as particular wheel profile expression formula, and for the design of xsect;

According to the height of described metal support and pitch angle, evenly connect xsect described in each, to obtain the profile of described metal support.

2. low radar scattering cross section metal support method for designing according to claim 1, is characterized in that, described in obtain the profile of described metal support after, also comprise:

Adopt method of moment or high-frequency asymptote technology, to obtain the corresponding relation between low radar scattering cross section and the frequency of described metal support.

3. low radar scattering cross section metal support method for designing according to claim 1, is characterized in that,

Selected xsect quantity to be designed is two, is respectively upper xsect and the lower xsect of described metal support.

4. a low radar scattering cross section metal support, is characterized in that, the cross-sectional profiles line of described metal support meets following specific formulation:

-L≤x≤0, wherein, H is minor semi-axis; L is major semi-axis; μ is the shape controlling elements of xsect, μ >0, and x is the horizontal ordinate of described cross-sectional profiles line; Y is the ordinate of described cross-sectional profiles line.

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