CN106486784A - Mirror antenna array and beam sweeping method - Google Patents

Abstract

The invention discloses a kind of mirror antenna array and beam sweeping method, wherein mirror antenna array includes programmable substrate and Meta Materials surface, the Meta Materials surface includes several active antenna element, and the active antenna element includes metamaterial unit and the active diode being connected between metamaterial unit；When the status park of active diode is different, the distribution of " 0 " on Meta Materials surface, one state is different；And then the radiation beam required for reflecting to form plane wave.The present invention can quickly design corresponding " 0 " and " 1 " coding arrangement, quickly control corresponding active diode, control beam-scanning angles and radiation beam by programmable substrate.Compared with traditional structure, it is not necessary to which mechanical rotation antenna structure can achieve to need the radiation beam of orientation angles, and overall volume reduces, and increase flexibility.

Description

Mirror antenna array and beam sweeping method

Technical field

The invention belongs to communication technical field, especially a kind of mirror antenna array.

Background technology

Radar antenna be in order to radiate and receive electromagnetic wave and determine the visual plant of its detection direction in radar, radarImportant tactical qualities, such as detection range, investigative range, search angle (orientation, pitching) precision, angular resolution and counter-measure energyPower etc., all relevant with radar antenna performance.

For realizing detection and tracking of the radar to target, general radar antenna is needed with beam scanning capabilities, by whichRadar antenna can be divided into mechanical scanning antennas, electronic scanning antenna and electromechanical three class of scanning antenna by scan mode.Mechanical scanningAntenna using more for parabola antenna and lens antenna, have the advantages that secondary lobe and back lobe level be little, directionality is good, thereforeObtain important in fields such as Aeronautics and Astronautics, satellite communication, mobile communication and be widely applied.But due to traditional parabola dayThe problems such as line and lens antenna have that volume is big, weight is high, installation is complicated, are not easy to integrated, airborne radar, spaceborne radar andMissile-borne radar etc. has to volume and quality in the system of rigors and is difficult to obtain application.The phased-array radar day of current main flowElectron scanning mode is employed in line, and in this antenna, each radar antenna unit connects a phase shifter, and all ofPhase shifter by computer controls, so as to realize the beam scanning of antenna.But the T/R component price such as phase shifter in phased array antennaExpensive.

Reflector antenna has the advantages that high-gain, Sidelobe, main lobe are narrow, high-gain is formed and can require shape rippleWhile bundle, feed is simple, design comparison is easy, cost is relatively low, can meet the requirement of multiple conventional radar system.Reflecting surface dayLine is one of principal mode of satellite communication ground based terminal station antenna, has at the aspect such as distance radio communication and high resolution radarExtensively apply.Reflector antenna is made up of a reflecting surface and feed antennas, by scattering of the reflecting surface to electromagnetic waveEffect forms desired antenna pattern.

But the volume of existing mirror antenna array is also than larger, wave beam adjusting function not enough comprehensively the shortcomings of.

Content of the invention

In order to the problems referred to above of prior art presence are solved, a kind of mirror antenna array is provided.

Specifically scheme is：A kind of mirror antenna array is provided, including programmable substrate and Meta Materials surface, described superMaterial surface includes several active antenna element, and the active antenna element includes metamaterial unit and is connected to metamaterial unitBetween active diode；When the status park of active diode is different, " 0 " on Meta Materials surface, one state are distributed notWith；And then the radiation beam required for reflecting to form plane wave.

In a further embodiment, mirror antenna array also includes driving source and metallic support, the driving source, canProgramming substrate is fixed on the metallic support with Meta Materials surface.

In a further embodiment, the Far-field scattering of the metamaterial unit

Wherein, θ andThe respectively angle of pitch of radiation beam and azimuth；D is the width of metamaterial unit；K is freely emptyBetween wave number；The phase place of each unit isN, m, n are natural number.The driving source is conical horn, the circular cone loudspeakerVertex angle theta=2arctan (a/2L), wherein a are bell mouth surface diameter, and L is loudspeaker radiation length.The conical horn is rotatedIt is connected on metallic support, the rotational angle of conical horn is 0-60 °.

The present invention also provides a kind of beam sweeping method, is realized based on above-mentioned mirror antenna array, the beam scanningMethod comprises the steps：According to the corresponding encoded surface of electromagnetism algorithm for inversion design；

Encoded surface is write FPGA control panel, controls the break-make of diode；

Super surface cell phase place changes, and plane wave obtains radiation beam after being reflected by super surface.

Compared with prior art, technical scheme has the advantages that：

(1), the active metamaterial unit of present invention design is achieved by the break-make of active diode and controls its not homophaseThe working condition " 0 " of position and " 1 ", encode inverse algorithm according to electromagnetism, by difference requirement of the radar system to radiation beam, can be fastCorresponding " 0 " and " 1 " coding arrangement of speed design, quickly controls corresponding active diode, controls ripple by programmable substrateBeam scanning angle and radiation beam.Compared with traditional parabola radar antenna, directly can carry out digital control, without the need for complex and expensivePhase shifter and ad/da converter, realize more fully wave beam adjusting function, can not only carry out beam scanning, additionally it is possible toHigh-gain simple beam, dualbeam and controlled multi-beam is produced, and flexibly can be switched.

(2), driving voltage of the present invention and low in energy consumption, simple structure.Programmable substrate can be driven by 5V voltage,And the operating current of single active diode very low (5.2mA), whole control panel and active Meta Materials surface power consumption low.Overall structure can generate 0 ° -70 ° of comprehensive scanning ripple using excitation loudspeaker source, Meta Materials surface and programmable substrate compositionBundle, compared with traditional structure, it is not necessary to which mechanical rotation antenna structure can achieve to need the radiation beam of orientation angles, overall bodyProduct reduces, and increases flexibility.

(3), reflecting surface of the present invention and excitation loudspeaker source are integrated on metallic support, by adjusting loudspeaker source with reflecting surfaceOrientation achieves that optimal reflected beam, is adaptable to different excitation loudspeaker and reflecting surface, with flexible modulability.

Description of the drawings

Fig. 1 a is the schematic diagram of the present invention；Fig. 1 b is the structural representation of the present invention.

Fig. 2 a, Fig. 2 b and Fig. 2 c are respectively front view, rearview and the side view of the active antenna element of the present invention.

Fig. 3 is the structure chart in the excitation loudspeaker source of the present invention.

Fig. 4 a and Fig. 4 b is side view and the top view of the antenna holder of the present invention.

Fig. 5 is the programmable substrate theory diagram of the present invention.

Fig. 6 a and Fig. 6 b is respectively the simple beam antenna pattern that the present invention is tested in 10GHz Frequency point.

The dualbeam antenna pattern that Fig. 7 a and Fig. 7 b is tested in 10GHz Frequency point for the present invention.

Fig. 8 is the workflow diagram of the present invention.

Specific embodiment

Applicant is thought after research：Traditional reflector antenna realizes desired spoke by the shape of design reflecting surfaceDirection is penetrated, and the structure of reflecting surface and performance have just been fixed, it is impossible to real-time control is carried out to antenna according to actual needs.ProgrammableReflector antenna has traditional parabolic reflector antenna and phased array antenna, by adjusting the microstrip reflection of two-dimensional structureThe unit arrangement of antenna, can realize single wave beam or multiple wave beams while working, and cover the spatial domain of given shape, in satelliteThe technical field such as communication and electronic countermeasure is obtained extensively to be applied.Microstrip reflection antenna is improve satellite communication system performance oneA kind of important means of a large amount of targets is sorted in guardian technique, and Modern Electronic Countermeasure.The present invention's described in detail belowTechnical scheme and case study on implementation.

In the embodiment shown in Fig. 1 a to Fig. 7, the mirror antenna array mainly includes loudspeaker driving source 1, Meta MaterialsSurface 5 and programmable substrate 4；Active antenna element 6 is made up of active diode device 2 and metamaterial unit 3；" 0 ", " 1 " surpassMaterial surface is made up of n × n active antenna element array；Programmable substrate is connected with Meta Materials surface by slot, is led toCross downloading wire and coded sequence is written to programmable substrate；The loudspeaker driving source, programmable substrate and " 0 ", " 1 " Meta Materials tableFace is fixed on metallic support.

Loudspeaker driving source is used as signal driving source, plane of departure ripple to " 0 ", " 1 " Meta Materials surface, the plane wave of its transmittingArea is approximate with Meta Materials surface size, maximum by plane wave reflection, forms high-gain, the preferable reflected beam of directionality,By adjust the position of loudspeaker driving source and azimuth can achieve to carry out the transmitting of different size of reflection plate antenna appropriateExcitation." 0 ", " 1 " Meta Materials surface change " 0 " on surface, one state distribution by the break-make for controlling active diode device,Radiation beam required for the plane wave of loudspeaker driving source is reflected to form.Programmable substrate according to radar beam requirement by spyFixed " 0 ", " 1 " coding distribution is write by FPGA control panel, controls the break-make of active diode device, by plane wave reflectionBecome specific radiation beam.

Loudspeaker driving source can provide plane wave excitation, it is ensured that on Meta Materials surface, all of active antenna element is receivedPlane wave phase amplitude is identical.The adjustable excitation loudspeaker source of metallic support 7 and the distance and bearing on Meta Materials surface, realize everyIndividual active metamaterial unit all may act on reflected beam, reach optimal reflecting effect.

In above-mentioned mirror antenna array, " 0 " and " 1 " working condition of the active antenna element has by controlThe break-make of source diode device is realized, 180 ° of the phase under two kinds of different working conditions in its operating frequency range, structure0 and 1 1bit is become to encode metamaterial unit.

As Fig. 2 a to Fig. 2 c show active antenna element structure, connected by two through holes in the radiation patch on surface respectivelyGround connection and positive source, power to active diode device 2, greatly simplify the power supply of whole system.

Wherein, in structure, parameter l1, l2 can change the operating frequency point of unit；W2 is the length of active diode device；According to the break-make of active diode device 2, phase in the case of being optimized available two kinds to parameter s1, s2 and w1180 °, then thus unit can design unit corresponding in each frequency of X-band.

The directionality that all of unit is formed on " 0 ", " 1 " Meta Materials surface is indicated by formula (1), wherein, θ andThe respectively angle of pitch of radiation beam and azimuth；Far-field scattering for metamaterial unit 3；K is free spaceWave number；D is the width of unit；The phase place of each unit isUsually 0 ° or 180 °.So can just be calculated anti-The directional diagram formed by the formula antenna of penetrating.

Programmable substrate is realized by FPGA control panel, have the advantages that low cost, be easily integrated, stability high, according toThe demand of radar emission wave beam, is write by downloading wire by the coding on electromagnetism algorithm for inversion calculated " 0 ", " 1 " Meta Materials surfaceEnter in the control module of FPGA, be to ensure that FPGA has enough load capacities, by rectification module rectification so as to footEnough driving currents, so as to control the both end voltage of active diode device, reach and realize to each diode break-make controlPurpose, so as to constitute two kinds of different working conditions that phase difference is 180 °.

The structural parameters in excitation loudspeaker source using conical horn, are designed and are launched in 10GHz frequency as shown in Fig. 2 a to Fig. 2 cPlane wave.Circular cone drift angle size θ=2arctan (a/2L)=2arctan can determine that by phase margin (δ not should be greater than 0.32 λ)(L/ (L+ δ)), wherein a are bell mouth surface diameter, and L is loudspeaker radiation length.According to center frequency point can determine that conical horn otherParameter, realizes loudspeaker excitation output plane ripple effect.

As shown in figures 4 a and 4b, reflecting plate is fixed on support one end to antenna holder structure, and loudspeaker driving source 1 is another in supportOne end, its position and the angle of pitch are variable.Apart from reflecting plate distance in scope 120mm～320mm adjustable, height change modelEnclose for 100mm～300mm, and loudspeaker can be rotated in 60 ° of angle, with higher controllability.

As shown in figure 8, the course of work of the present invention is：First plane wave is sent to " 0 ", " 1 " super material by loudspeaker driving sourceMaterial surface, is realized manipulating the characteristic of electromagnetic wave according to the Meta Materials surface of different working condition, will be calculated by programmable substrateThe different coding sequence statement for drawing is to " 0 ", " 1 " Meta Materials surface, it is achieved that the control of different electromagnetic beams and scanning, can shapeBecome the radiation beam such as simple beam, dualbeam and four wave beams.

In conjunction with the reflective programmable antenna array of the inventive method, it is made up of 20 × 20 active antenna element, reflectionThe overall size 200 × 200 × 1.8 (mm) of plate, working frequency range is 9.7-10.2GHz, and being written to coded sequence by PC canIn programming substrate (FPGA), realize controlling Meta Materials surface " 0 ", " 1 " distribution by the break-make of active diode device, it is achieved thatBeam scanning control and simple beam, dualbeam and multi-beam are switched fast.

Fig. 6 a and Fig. 6 b, Fig. 7 a and Fig. 7 b are respectively the simple beam that the example of the present invention tests and double in 10GHz Frequency pointBeam pattern.According to radar beam direction demand, by electromagnetism inverse calculation, 20 required for quick design excess of export surfaceThe coded sequence of × 20 each unit, is write the coded program of specific direction angle by PC end by corresponding FPGA control panel,By in the chip of 0 ° of simple beam, 10 °, 20 °, 30 °, 40 °, 50 °, 60 °, 70 ° coded sequence distribution write FPGA substrate.TestThe simple beam performance of whole mirror antenna (gain and directional diagram).Change the coding arrangement on Meta Materials surface, encourage loudspeakerThe radiation beam of accurate high-gain, low sidelobe after the plane wave in source is reflected by super surface, is generated, has been reached control wave beam and has sweptThe function of retouching, meets requirement of the radar system to antenna difference radiation beam.Write coded sequence is scanned through to multi-beamBe -45 ° to angle of radiation, 30 ° of dualbeam radiation be tested, as a result show to produce corresponding ripple in respective anglesBundle, realizes the radiation of manipulation electromagnetic beam, realizes Protean beam scanning function by changing the coding on super surface.

In a word, the invention discloses a kind of mirror antenna array, the mirror antenna array includes multiple active antennasUnit, programmable substrate, driving source electromagnetic horn and metallic support.The active antenna element is by active diode and Meta MaterialsUnit is combined into, and can control its working frequency range by changing unit size.Programmable substrate (FPGA) is carried on the back in reflecting surfacePlate, is connected with each antenna element by the direct insertion terminal of 400 pins, and on control active antenna element, each diode is logicalDisconnected, reach the working condition of unit on control antenna reflective face.The excitation loudspeaker source is conical horn, can produce wide bandPlane wave, by the excitation of loudspeaker driving source, aerial array is operated in different radiation modes, produce different angles with differenceSeveral radiation beam, meets the radar system demand different to wave beam.Metallic support is in order to constant excitation loudspeaker and antenna-reflectedPlate, can adjust the orientation of excitation loudspeaker source and reflecting surface, realize optimal reflected beam output.

The preferred embodiment of the present invention described in detail above, but, the present invention is not limited in above-mentioned embodimentDetail, in the range of the technology design of the present invention, multiple equivalents can be carried out to technical scheme,These equivalents belong to protection scope of the present invention.It is further to note that being retouched in above-mentioned specific embodimentEach particular technique feature that states, in the case of reconcilable, can be combined by any suitable means.In order to avoidUnnecessary repetition, the present invention are no longer separately illustrated to various possible combinations.

Claims (6)

1. a kind of mirror antenna array, it is characterised in that including programmable substrate and Meta Materials surface, the Meta Materials surfaceIncluding several active antenna element, the active antenna element includes metamaterial unit and is connected to having between metamaterial unitSource diode；When the status park of active diode is different, the distribution of " 0 " on Meta Materials surface, one state is different；And then willPlane wave reflects to form required radiation beam.

2. mirror antenna array as claimed in claim 1, it is characterised in that also include driving source and metallic support, describedDriving source, programmable substrate and Meta Materials surface are fixed on the metallic support.

3. mirror antenna array as claimed in claim 1 or 2, it is characterised in that the Far-field scattering of the metamaterial unit

Wherein, θ andThe respectively angle of pitch of radiation beam and azimuth；D is the width of metamaterial unit；The phase of each unitPosition isK is the wave number of free space；N, m, n are natural number.

4. mirror antenna array as claimed in claim 1, it is characterised in that the driving source is conical horn, the circleVertex angle theta=2arctan (a/2L), the wherein a of cone loudspeaker is bell mouth surface diameter, and L is loudspeaker radiation length.

5. mirror antenna array as claimed in claim 4, it is characterised in that the conical horn is rotationally connected with metal and props upOn frame, the rotational angle of conical horn is 0-60 °.

6. a kind of beam sweeping method, it is characterised in that realized based on claim 1 to 5 any one mirror antenna array, instituteState beam sweeping method to comprise the steps：

According to the corresponding encoded surface of electromagnetism algorithm for inversion design；

Encoded surface is write FPGA control panel, controls the break-make of diode；

Super surface cell phase place changes, and plane wave obtains radiation beam after being reflected by super surface.