CN103745060A - Large-scale antenna dome electrical performance compensation method based on reflector shaping - Google Patents

Abstract

The invention discloses a large-scale antenna dome electrical performance compensation method based on reflector shaping, and aims to solve the problem that an antenna dome excessively affects antenna electrical performance. According to the technical scheme, the method includes calculating antenna far field according to aperture field; drawing a far field pattern and extracting electrical performance indicators; calculating the aperture field penetrating the antenna dome; calculating coordinates of points on a shaped reflector; calculating the aperture field penetrating the antenna dome the antenna dome after reflector shaping; calculating the far fields of an antenna with a dome before and after reflector shaping, and drawing far field patterns and extracting electrical performance indicators; comparing the far field patterns and electrical performance indicators of an antenna without a dome, the antenna with the dome before and after reflector shaping, if electrical performance requirements are met, outputting the far field patterns and electrical performance indicators of the antenna without a dome, the antenna with the dome before and after reflector shaping; if not, performing fine-tuning on the shaped reflector, and repeating the processes till the electrical performance meets the requirements. By the aid of the method, the electrical performance of a system of an antenna with a dome can be optimized effectively, and the method can be applied in antenna dome analysis and design.

Description

Large-scale antenna cover electrical property compensation method based on reflecting surface figuration

Technical field

The invention belongs to Radar Antenna System field, specifically a kind of antenna house electrical property compensation method, can be used for the electrical property of the reflector antenna system with dielectric interlayer formula antenna house to compensate.

Technical background

Antenna house is that protection antenna is avoided the wave transparent shell of natural environment influence, is by coverture natural or that artificial dielectric's material is made, or the bright window of electromagnetism of the special shape consisting of the dielectric housing of truss support.The antenna house of excellent in design; except having protectiveness, conduction, reliability, disguise and the function such as ornamental, can also extend whole system each several part serviceable life, reduce Life Cost and running cost, simplified design, reduction maintenance cost, guarantee antenna surface and position degree of accuracy, to antenna operation personnel, create good working environment.But antenna house also can exert an influence to the electromagnetic radiation of ideal antenna, desirable antenna electric performance is decreased.

Along with the progress of China's aviation, meteorology and military technology and the development of military situation, the research of carrying out the High Accuracy Radars such as long-range precision tracking instrumentation radar and high-gain aerial has become urgent task with manufacture.And the physical environment of Special geographical position is larger on the impact of equipment, being equipped with antenna house becomes these radars, the requisite requirement of antenna, and dielectric interlayer formula antenna house is widely used with its good structural behaviour and electrical property.

Du Yaowei has analyzed the impact of dielectric interlayer formula antenna house on Antenna Far Field in classical works < < antenna house telecommunications design method > > mono-book of publishing for 1993, first the method obtains the transmission coefficient of antenna house, then according to the transmission coefficient of the aperture field of antenna and antenna house, obtain the aperture field after covering, integration is obtained the far field of covering aft antenna.The deficiency of the method is: the electrical property that there is no to consider to improve by reflecting surface figuration band cover antenna system.

Ren Yahong is used physical optical method analytical approach in the mono-reflector antenna figuration research of the paper < < > > of 2012, reflector shape is represented by one group of orthogonal polynomial, by optimizing multinomial coefficient, carry out Shaped-beam reflector antenna, to realize the desired electrical property of antenna, yet the method is not applied to reflecting surface figuration in the compensation of covering aft antenna electrical property.

Summary of the invention

The object of the invention is to for above-mentioned the deficiencies in the prior art, a kind of large-scale antenna cover electrical property compensation method based on reflecting surface figuration is provided, to improve the electrical property of band cover antenna system.

For achieving the above object, technical scheme of the present invention comprises the steps:

(1) according to known antenna aperture field E (x, y), calculate the far field F (θ, φ) of antenna, draw far-field pattern T ₁, and from far-field pattern, extract electrical performance indexes, i.e. maximum field strength G ₁, the first secondary lobe L ₁and beam angle R ₁;

(2) by transmission line theory, calculate the transmission coefficient at each point place on antenna house and calculate through the aperture field after antenna house: $E^{\&prime;}(x,y)=E(x,y)\&CenterDot;\stackrel{\&CenterDot;}{T_M};$

(3) according to the aperture field E ' (x, y) seeing through after antenna house, calculate the far field F ' (θ, φ) of band cover antenna, draw far-field pattern T ₂, and from this far-field pattern, extract maximum field strength G ₂, the first secondary lobe and beam angle R ₂these electrical performance indexes;

(4) with (x, y, z), represent the coordinate of ideally-reflecting face, the z coordinate that changes ideally-reflecting face is z ', and the coordinate that obtains figuration reflecting surface is (x, y, z ');

(5), according to the coordinate of putting on gained Shaped-beam reflector antenna, calculate the aperture field phase difference ψ that reflecting surface figuration causes, and then after calculating reflecting surface figuration, see through the aperture field E " (x, y) of antenna house;

(6) according to seeing through the aperture field E of antenna house after reflecting surface figuration, " (x, y), after calculating reflecting surface figuration, " (θ, φ) draws this far-field pattern T to the far field F of band cover antenna ₃, and from far-field pattern, extract maximum field strength G ₃, the first secondary lobe L ₃and beam angle R ₃these electrical performance indexes;

(7) according to the far-field pattern obtaining in step (1), (3), (6) and corresponding electrical performance indexes, calculate the change amount of covering aft antenna electrical performance indexes, and the change amount of being with the electrical performance indexes of cover antenna system after calculating reflecting surface figuration;

(8) according to the requirement on electric performance of Antenna Design, judge whether the electrical performance indexes change amount of system meets preset requirement after covering and reflecting surface figuration, if met, export the far-field pattern and the corresponding electrical performance indexes that in step (1), (3), (6), obtain; Otherwise, figuration reflecting surface is finely tuned, and repeating step (5) is to step (8), until meet requirement on electric performance.

The present invention is owing to adopting reflecting surface figuration to compensate the phase distortion of covering aft antenna aperture field, thereby compared with prior art, improved the electrical property of band cover antenna system.

Simulation result shows, after adopting this method to compensate, is with maximum field strength, minor level and the beam angle of cover antenna system all to have clear improvement, and antenna house diminishes to the adverse effect of antenna electric performance.

Accompanying drawing explanation

Fig. 1 is the general flow chart of realizing of the present invention;

Fig. 2 calculates the sub-process figure that sees through the aperture field after antenna house in the present invention;

Fig. 3 is the structural drawing of dielectric interlayer formula antenna house;

Fig. 4 is the cross section structure schematic diagram of the antenna house in Fig. 3;

Fig. 5 is the far-field pattern of antenna;

Fig. 6 is the far-field pattern of band cover antenna;

Fig. 7 is the far-field pattern of band cover antenna after reflecting surface figuration.

Embodiment

Referring to accompanying drawing, the present invention is described in further detail.

With reference to Fig. 1, concrete steps of the present invention are as follows:

Step 1, calculates Antenna Far Field according to the known aperture field of antenna.

(1a) take antenna opening diametric plane center as initial point O, in the plane that is xy at bore face, set up a rectangular coordinate system O-xyz, according to known antenna aperture field distribution E (x, y), calculate the far field value F (θ, φ) of antenna:

$F(\mathrm{\&theta;},\mathrm{\&phi;})=\underset{S}{\&Integral;\&Integral;}E(x,y)e^{{\mathrm{<figure-callout\; id="0"\; label="jk"\; filenames="HDA0000457389250000041.png,HDA0000457389250000042.png"\; state="\{\{state\}\}">jk</figure-callout>}}_0\sin \mathrm{\&theta;}(x\cos \mathrm{\&phi;}+y\sin \mathrm{\&phi;})}\mathrm{dxdy},$

Wherein, θ, φ are the spherical coordinates angle of observation point in rectangular coordinate system O-xyz, k ₀for free-space propagation constant, by formula

calculate,, λ is the wavelength of antenna, according to operating frequency of antenna f and light velocity c, passes through formula

calculate the area that s is integral unit;

(1b) according to gained Antenna Far Field F (θ, φ), draw far-field pattern T ₁, and extract electrical performance indexes from this far-field pattern, i.e. maximum field strength G ₁, the first secondary lobe L ₁with beam angle R ₁.

Step 2, calculates the aperture field seeing through after antenna house.

With reference to Fig. 2, being implemented as follows of this step:

(2a) in commercial model analysis software, according to the version of antenna house, set up the geometric model of dielectric interlayer formula antenna house, it is λ that the grid length of side is set, and model is carried out to grid division;

(2b), according to the structural parameters of antenna house and material parameter, by transmission line theory, calculate the transmission coefficient at each point place on antenna house $\stackrel{\&CenterDot;}{T_M:}$

(2b1), according to the aperture field of the geometric configuration of antenna house and incident, obtain the incidence angle θ at each point place on antenna house _mwith polarizing angle φ _m, the normal angle that is about to electromagnetic wave incident ray and incidence point place is designated as incidence angle θ _m, the angle of polarization of electromagnetic wave direction and plane of incidence is designated as to polarizing angle φ _m, wherein plane of incidence consists of the normal at electromagnetic wave incident ray and incidence point place;

(2b2) according to the thickness d of antenna house, relative dielectric constant ε _r, losstangenttanδ, calculate the horizontal polarization component transmission coefficient at each point place on antenna house

with vertical polarization component transmission coefficient

$\stackrel{\&CenterDot;}{T_H}=\frac{2}{\stackrel{\&CenterDot;}{A}+\stackrel{\&CenterDot;}{B_H}+\stackrel{\&CenterDot;}{C_H}+\stackrel{\&CenterDot;}{D}}=T_H{e}^{{-\mathrm{j\&eta;}}_H}$

$\stackrel{\&CenterDot;}{T_V}=\frac{2}{\stackrel{\&CenterDot;}{A}+\stackrel{\&CenterDot;}{B_V}+\stackrel{\&CenterDot;}{C_V}+\stackrel{\&CenterDot;}{D}}=T_V{e}^{{-\mathrm{j\&eta;}}_V}$

Wherein, $\stackrel{\&CenterDot;}{A}=\mathrm{ch}\left(j\stackrel{\&CenterDot;}{V}d\right),\stackrel{\&CenterDot;}{B_H}=\frac{\stackrel{\&CenterDot;}{Z_{1H}}\mathrm{sh}\left(j\stackrel{\&CenterDot;}{V}d\right)}{Z_H},\stackrel{\&CenterDot;}{B_V}=\frac{\stackrel{\&CenterDot;}{Z_{1V}}\mathrm{sh}\left(j\stackrel{\&CenterDot;}{\mathrm{Vd}}\right)}{Z_V},\stackrel{\&CenterDot;}{C_H}=\frac{Z_H\mathrm{sh}\left(j\stackrel{\&CenterDot;}{\mathrm{Vd}}\right)}{\stackrel{\&CenterDot;}{Z_{1H}}},$

$\stackrel{\&CenterDot;}{C_V}=\frac{Z_V\mathrm{sh}\left(j\stackrel{\&CenterDot;}{\mathrm{Vd}}\right)}{\stackrel{\&CenterDot;}{Z_{1V}}},\stackrel{\&CenterDot;}{D}=\mathrm{ch}\left(j\stackrel{\&CenterDot;}{\mathrm{Vd}}\right),\stackrel{\&CenterDot;}{V}=\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}\sqrt{\stackrel{\&CenterDot;}{{\mathrm{\&epsiv;}}_r}-{\sin }^2{\mathrm{\&theta;}}_M},\stackrel{\&CenterDot;}{Z_{1H}}=\sqrt{\stackrel{\&CenterDot;}{{\mathrm{\&epsiv;}}_r}-\frac{{\sin }^2{\mathrm{\&theta;}}_M}{{\stackrel{\&CenterDot;}{\mathrm{\&epsiv;}}}_r}},\stackrel{\&CenterDot;}{Z_{1V}}=\frac{1}{\sqrt{\stackrel{\&CenterDot;}{{\mathrm{\&epsiv;}}_r}-{\sin }^2{\mathrm{\&theta;}}_M}},$

$\stackrel{\&CenterDot;}{{\mathrm{\&epsiv;}}_r}={\mathrm{\&epsiv;}}_r(1-j\tan \mathrm{\&delta;}),$ Z _H＝cosθ _M， $Z_V=\frac{1}{\cos {\mathrm{\&theta;}}_M},$ These parameters are intermediate variable; T _h, T _vbe respectively

mould value, η _h, η _vbe respectively

phase place;

(2b3) according to horizontal polarization component transmission coefficient

with vertical polarization component transmission coefficient obtain the transmission coefficient of main pole polarization component:

$\stackrel{\&CenterDot;}{T_M}=\sqrt{{\mathrm{<figure-callout\; id="2"\; label="T\; H"\; filenames="HDA0000457389250000041.png,HDA0000457389250000042.png"\; state="\{\{state\}\}">T</figure-callout>}}_H^{}{\cos }^4{\mathrm{\&phi;}}_M+{\mathrm{<figure-callout\; id="2"\; label="T\; V"\; filenames="HDA0000457389250000041.png,HDA0000457389250000042.png"\; state="\{\{state\}\}">T</figure-callout>}}_V^{}{\sin }^4{\mathrm{\&phi;}}_M+{2T}_H{T}_V\cos ({\mathrm{\&eta;}}_H-{\mathrm{\&eta;}}_V){\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA0000457389250000041.png,HDA0000457389250000042.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2{\mathrm{\&phi;}}_M{\sin }^2{\mathrm{\&phi;}}_M}\&CenterDot;e^{-j({\mathrm{\&eta;}}_H-\mathrm{\&alpha;})},$

Wherein, $\mathrm{\&alpha;}=\arctan \frac{T_V{\sin }^2{\mathrm{\&phi;}}_M\sin ({\mathrm{\&eta;}}_H-{\mathrm{\&eta;}}_V)}{{\mathrm{<figure-callout\; id="2"\; label="T\; H\; cos"\; filenames="HDA0000457389250000041.png,HDA0000457389250000042.png"\; state="\{\{state\}\}">T</figure-callout>}}_H{\cos }^{}{}^2{\mathrm{\&phi;}}_M+T_V\cos ({\mathrm{\&eta;}}_H-{\mathrm{\&eta;}}_V){\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA0000457389250000041.png,HDA0000457389250000042.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2{\mathrm{\&phi;}}_M}$ For intermediate variable;

(2c) will incide aperture field on cover body and be multiplied by the transmission coefficient of its corresponding point position, calculate the aperture field seeing through after antenna house: $E^{\&prime;}(x,y)=E(x,y)\&CenterDot;\stackrel{\&CenterDot;}{T_M}.$

Step 3, the far field of calculating band cover antenna.

(3a), according to the aperture field E ' (x, y) seeing through after antenna house, calculate the far field F ' (θ, φ) of band cover antenna:

$F^{\&prime;}(\mathrm{\&theta;},\mathrm{\&phi;})=\underset{S}{\&Integral;\&Integral;}{E}^{\&prime;}(x,y)e^{{\mathrm{<figure-callout\; id="0"\; label="jk"\; filenames="HDA0000457389250000041.png,HDA0000457389250000042.png"\; state="\{\{state\}\}">jk</figure-callout>}}_0\sin \mathrm{\&theta;}(x\cos \mathrm{\&phi;}+y\sin \mathrm{\&phi;})}\mathrm{dxdy},$

(3b) according to gained far field F ' (θ, φ), draw far-field pattern T ₂, and from this far-field pattern, extract maximum field strength G ₂, the first secondary lobe L ₂with beam angle R ₂these electrical performance indexes.

Step 4, the coordinate of each point on calculating figuration reflecting surface.

The coordinate that represents ideally-reflecting face with (x, y, z), the z coordinate that changes ideally-reflecting face is z ', the coordinate that obtains figuration reflecting surface is (x, y, z '),

_z' computing formula be:

$z^{\&prime;}=\frac{x^2+y^2-{2\mathrm{Qf}}_l-{\mathrm{<figure-callout\; id="2"\; label="Q"\; filenames="HDA0000457389250000041.png,HDA0000457389250000042.png"\; state="\{\{state\}\}">Q</figure-callout>}}^2}{{4f}_l+2Q},$

F wherein _lfor the focal length of antenna,

for intermediate variable, γ (x, y) is that point (x, y) is located the phase place of transmission coefficient and the phase difference value that point (0,0) is located transmission coefficient, k ₀for free-space propagation constant, by formula

calculate, λ is the wavelength of antenna, according to operating frequency of antenna f and light velocity c, passes through formula

calculate.

Step 5, calculates the aperture field that sees through antenna house after reflecting surface figuration.

(5a) calculate the aperture field phase difference ψ that reflecting surface figuration causes:

$\mathrm{\&Delta;\&psi;}=e^{{-\mathrm{jk}}_0(z-z^{\&prime;})},$

The coordinate that wherein z is ideally-reflecting face, z ' is the coordinate of figuration reflecting surface, k ₀for free-space propagation constant, by formula

calculate, λ is the wavelength of antenna;

(5b) after calculating reflecting surface figuration, see through the aperture field E of antenna house " (x, y):

E″(x,y)＝E′(x,y)·Δψ，

Wherein E ' (x, y) is for seeing through the aperture field after antenna house, and Δ ψ is the aperture field phase differential that reflecting surface figuration causes.

Step 6, calculates the far field of being with cover antenna after reflecting surface figuration.

(6a) according to seeing through the rear aperture field of antenna house after reflecting surface figuration

after calculating reflecting surface figuration, be with the far field F that covers antenna " (θ, φ):

$F^{\&prime;\&prime;}(\mathrm{\&theta;},\mathrm{\&phi;})=\underset{S}{\&Integral;\&Integral;}{E}^{\&prime;\&prime;}(x,y)e^{{\mathrm{<figure-callout\; id="0"\; label="jk"\; filenames="HDA0000457389250000041.png,HDA0000457389250000042.png"\; state="\{\{state\}\}">jk</figure-callout>}}_0\sin \mathrm{\&theta;}(x\cos \mathrm{\&phi;}+y\sin \mathrm{\&phi;})}\mathrm{dxdy},$

(6b) according to gained far field F, " (θ, φ) draws far-field pattern T ₃, and from this far-field pattern, extract maximum field strength G ₃, the first secondary lobe L ₃with beam angle R ₃these electrical performance indexes.

Step 7, according to the electrical performance indexes without cover antenna and band cover antenna, calculates the change amount of covering aft antenna electrical performance indexes.

(7a) according to the maximum field strength G without cover antenna ₁maximum field strength G with band cover antenna ₂, after calculating covering, maximum field strength reduces value: Δ G ₁=G ₁-G ₂;

(7b) according to the first secondary lobe L without cover antenna ₁the first secondary lobe L with band cover antenna ₂, the first secondary lobe lift-off value after calculating covering: Δ L ₁=L ₂-L ₁;

(7c) according to the beam angle R without cover antenna ₁beam angle R with band cover antenna ₂, beam angle changing value after calculating covering: Δ R ₁=R ₂-R ₁.

Step 8, according to the electrical performance indexes of band cover antenna after band cover antenna and reflecting surface figuration, the change amount of the electrical performance indexes of band cover antenna after calculating reflecting surface figuration.

(8a) according to the maximum field strength G of band cover antenna ₂maximum field strength G with band cover antenna after reflecting surface figuration ₃, after calculating reflecting surface figuration, maximum field strength reduces value: Δ G ₂=G ₂-G ₃;

(8b) according to the first secondary lobe L of band cover antenna ₂the first secondary lobe L with band cover antenna after reflecting surface figuration ₃, the first secondary lobe lift-off value after calculating reflecting surface figuration: Δ L ₂=L ₃-L ₂;

(8c) according to the beam angle R of band cover antenna ₂cover the beam angle R of antenna with reflecting surface figuration offspring ₃, beam angle changing value after calculating reflecting surface figuration: Δ R ₂=R ₃-R ₂.

Step 9, judges whether the electrical property of system meets the demands after covering and reflecting surface figuration.

According to the requirement on electric performance of Antenna Design, judge whether the electrical performance indexes change amount of system meets preset requirement after covering and reflecting surface figuration, if met, export the far-field pattern and the corresponding electrical performance indexes that in step 1, step 3, step 6, obtain; Otherwise, figuration reflecting surface is finely tuned, and repeats step 5 to step 9, until meet requirement on electric performance.

Advantage of the present invention can further illustrate by following emulation experiment:

1. simulation parameter

The 9.14m dielectric interlayer formula antenna house of certain ground satellite communication station, structure as shown in Figure 3, adopt A interlayer form, as shown in Figure 4, single-layer skins thickness 0.5mm, single layer core layer thickness 43mm, skin material specific inductive capacity is 4.2, dielectric loss angle tangent is 0.026, and core material specific inductive capacity is 1.15, and dielectric loss angle tangent is 0.0098.Inside antenna is single reflector antenna of 5.2m bore, and its burnt footpath ratio is 0.4, and frequency of operation is 5.6GHz.

2. emulation content and result

Emulation 1, the far field of calculating antenna, draws far-field pattern as shown in Figure 5, and the electrical performance indexes that extracts Fig. 5 is as shown in table 1.

Emulation 2, the far field of calculating band cover antenna, draws far-field pattern as shown in Figure 6, and the electrical performance indexes that extracts Fig. 6 is as shown in table 1.

Emulation 3, calculates the far field of being with cover antenna after reflecting surface figuration, draws far-field pattern as shown in Figure 7, and the electrical performance indexes that extracts Fig. 7 is as shown in table 1.

The electrical performance indexes of table 1 system

As seen from Table 1, the maximum field strength of covering aft antenna reduces, and minor level raises, and beam angle increases, and after adopting reflecting surface figuration to compensate, the maximum field strength of antenna, minor level and beam angle all have clear improvement, antenna house diminishes to the adverse effect of antenna electric performance.

Above-mentioned emulated data proves, the present invention can effectively improve the electrical property of band cover antenna system.

Claims (6)

1. the large-scale antenna cover electrical property compensation method based on reflecting surface figuration, is characterized in that comprising the steps:

(1) according to known antenna aperture field E (x, y), calculate the far field F (θ, φ) of antenna, draw far-field pattern T ₁, and from far-field pattern, extract electrical performance indexes, i.e. maximum field strength G ₁, the first secondary lobe L ₁and beam angle R ₁;

(2) by transmission line theory, calculate the transmission coefficient at each point place on antenna house and calculate through the aperture field after antenna house: $E^{\&prime;}(x,y)=E(x,y)\&CenterDot;\stackrel{\&CenterDot;}{T_M};$

(3) according to the aperture field E ' (x, y) seeing through after antenna house, calculate the far field F ' (θ, φ) of band cover antenna, draw far-field pattern T ₂, and from this far-field pattern, extract maximum field strength G ₂, the first secondary lobe and beam angle R ₂these electrical performance indexes;

(4) with (x, y, z), represent the coordinate of ideally-reflecting face, the z coordinate that changes ideally-reflecting face is z ', and the coordinate that obtains figuration reflecting surface is (x, y, z ');

(5), according to the coordinate of putting on gained Shaped-beam reflector antenna, calculate the aperture field phase difference ψ that reflecting surface figuration causes, and then after calculating reflecting surface figuration, see through the aperture field E " (x, y) of antenna house;

(6) according to seeing through the aperture field E of antenna house after reflecting surface figuration, " (x, y), after calculating reflecting surface figuration, " (θ, φ) draws this far-field pattern T to the far field F of band cover antenna ₃, and from far-field pattern, extract maximum field strength G ₃, the first secondary lobe L ₃and beam angle R ₃these electrical performance indexes;

(7) according to the far-field pattern obtaining in step (1), (3), (6) and corresponding electrical performance indexes, calculate the change amount of covering aft antenna electrical performance indexes, and the change amount of being with the electrical performance indexes of cover antenna system after calculating reflecting surface figuration;

(8) according to the requirement on electric performance of Antenna Design, judge whether the electrical performance indexes change amount of system meets preset requirement after covering and reflecting surface figuration, if met, export the far-field pattern and the corresponding electrical performance indexes that in step (1), (3), (6), obtain; Otherwise, figuration reflecting surface is finely tuned, and repeating step (5) is to step (8), until meet requirement on electric performance.

2. the large-scale antenna cover electrical property compensation method based on reflecting surface figuration according to claim 1, is characterized in that the z coordinate of change ideally-reflecting face in described step (4) is z ', by following formula, calculates:

$z^{\&prime;}=\frac{x^2+y^2-{2\mathrm{Qf}}_l-Q^2}{{4f}_l+2Q}$

F wherein _lfor the focal length of antenna,

for intermediate variable, γ (x, y) is that point (x, y) is located the phase place of transmission coefficient and the phase difference value that point (0,0) is located transmission coefficient, k ₀for free-space propagation constant, by formula

calculate,, λ is the wavelength of antenna, according to operating frequency of antenna f and light velocity c, passes through formula

calculate.

3. the large-scale antenna cover electrical property compensation method based on reflecting surface figuration according to claim 1, is characterized in that calculating the aperture field phase difference ψ that reflecting surface figuration causes in described step (5), by following formula, calculates:

$\mathrm{\&Delta;\&psi;}=e^{{-\mathrm{jk}}_0(z-z^{\&prime;})},$

The coordinate that wherein z is ideally-reflecting face, z ' is the coordinate of figuration reflecting surface,

λ is the wavelength of antenna, according to operating frequency of antenna f and light velocity c, passes through formula

calculate.

4. the large-scale antenna cover electrical property compensation method based on reflecting surface figuration according to claim 1, is characterized in that calculating in described step (5) the aperture field E that sees through antenna house after reflecting surface figuration " (x, y), by following formula, calculate:

E″(x,y)＝E′(x,y)·Δψ，

Wherein E ' (x, y) is for seeing through the aperture field after antenna house, and Δ ψ is the aperture field phase differential that reflecting surface figuration causes.

5. the large-scale antenna cover electrical property compensation method based on reflecting surface figuration according to claim 1, is characterized in that the middle change amount of calculating covering aft antenna electrical performance indexes of described step (7), comprising:

After covering, maximum field strength reduces value: Δ G ₁=G ₁-G ₂,

The first secondary lobe lift-off value after covering: Δ L ₁=L ₂-L ₁,

Beam angle changing value after covering: Δ R ₁=R ₂-R ₁,

G wherein ₁, L ₁, R ₁be respectively the far-field pattern T from antenna ₁the maximum field strength of middle extraction, the first secondary lobe and beam angle, G ₂, L ₂, R ₂be respectively from the far-field pattern T of band cover antenna ₂the maximum field strength of middle extraction, the first secondary lobe and beam angle.

6. the large-scale antenna cover electrical property compensation method based on reflecting surface figuration according to claim 1, is characterized in that the change amount that in described step (7), after calculating reflecting surface figuration, band covers the electrical performance indexes of antenna system, comprising:

After reflecting surface figuration, maximum field strength reduces value: Δ G ₂=G ₂-G ₃,

The first secondary lobe lift-off value after reflecting surface figuration: Δ L ₂=L ₃-L ₂,

Beam angle changing value after reflecting surface figuration: Δ R ₂=R ₃-R ₂,

G wherein ₂, L ₂, R ₂be respectively from the far-field pattern T of band cover antenna ₂the maximum field strength of middle extraction, the first secondary lobe and beam angle, G ₃, L ₃, R ₃be respectively the far-field pattern T of band cover antenna from reflecting surface figuration ₃the maximum field strength of middle extraction, the first secondary lobe and beam angle.

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