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CN110112541B - Airborne radar and telemetering integrated array antenna - Google Patents

Airborne radar and telemetering integrated array antenna Download PDF

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Publication number
CN110112541B
CN110112541B CN201910236201.4A CN201910236201A CN110112541B CN 110112541 B CN110112541 B CN 110112541B CN 201910236201 A CN201910236201 A CN 201910236201A CN 110112541 B CN110112541 B CN 110112541B
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CN
China
Prior art keywords
antenna
unit
units
telemetering
radar
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Expired - Fee Related
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CN201910236201.4A
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Chinese (zh)
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CN110112541A (en
Inventor
孙斌
王洋
王大军
张健
黄璐
华煜明
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63921 Troops of PLA
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63921 Troops of PLA
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00Details of, or arrangements associated with, antennas
    • H01Q1/27Adaptation for use in or on movable bodies
    • H01Q1/28Adaptation for use in or on aircraft, missiles, satellites, or balloons
    • H01Q1/285Aircraft wire antennas
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00Details of, or arrangements associated with, antennas
    • H01Q1/36Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00Details of, or arrangements associated with, antennas
    • H01Q1/52Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure
    • H01Q1/521Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure reducing the coupling between adjacent antennas
    • H01Q1/523Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure reducing the coupling between adjacent antennas between antennas of an array
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q15/00Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
    • H01Q15/24Polarising devices; Polarisation filters 
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00Antenna arrays or systems
    • H01Q21/24Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00Antenna arrays or systems
    • H01Q21/29Combinations of different interacting antenna units for giving a desired directional characteristic
    • H01Q21/293Combinations of different interacting antenna units for giving a desired directional characteristic one unit or more being an array of identical aerial elements

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  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Remote Sensing (AREA)
  • Physics & Mathematics (AREA)
  • Astronomy & Astrophysics (AREA)
  • General Physics & Mathematics (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)

Abstract

The invention discloses an airborne radar and telemetering integrated array antenna which can solve the problems of radar/telemetering common-aperture layout, antenna unit selection and design and antenna passive intermodulation. The technical scheme of the invention is as follows: the integrated array antenna consists of a common antenna unit, wherein the common antenna unit consists of a horizontal polarization unit and a vertical polarization unit which share the same aperture. The horizontal polarization unit covers radar and telemetry frequency bands. The n common antenna units form a sub-array, all horizontal polarization units in each sub-array are connected with radar channels, every other common antenna unit serves as a telemetering unit, and the horizontal polarization units and the vertical polarization units in the telemetering units are respectively connected with one telemetering channel.

Description

Airborne radar and telemetering integrated array antenna
Technical Field
The invention relates to the technical field of airborne measurement and control, in particular to an airborne radar and telemetering integrated array antenna.
Background
A radar system and a remote measuring system in the airborne comprehensive measurement and control system adopt a digital array system, the radar adopts horizontal polarization, the remote measuring adopts double-linear polarization and the cooperative work is needed. The antenna array surface is a key component of the system, in order to meet the detection/remote measurement index requirements of the system, the remote measurement antenna needs a full aperture, and the full aperture for the radar is beneficial to reducing the peak power of a radar unit and the design difficulty of electromagnetic compatibility. If two sets of independent antenna array surfaces are adopted according to the conventional design idea, the two sets of antennas are too large in size and cannot be simultaneously installed in the rear antenna housing in a coplanar manner; if a back-to-back installation mode is selected, the requirement of cooperative work of radar and remote measurement cannot be met. Therefore, the radar and telemetry antennas must be of a common aperture design. By adopting a radio frequency aperture comprehensive design idea and integrating two sets of antennas in one antenna aperture, the problems of coplanar installation and cooperative work of the radar antenna and the telemetering antenna can be solved. Meanwhile, the detection performance of the radar and the receiving performance of a remote measuring system need to be ensured, and the ultra-low side lobe performance of the antenna needs to be realized.
Compared with two conventional independent antenna array surfaces, the design idea of radio frequency aperture synthesis has obvious technical advantages, and simultaneously brings more complicated technical problems to be solved urgently, and the technical difficulties mainly comprise the following three points:
one, radar/telemetering common aperture layout problem
The array layout is a key link of radar/telemetering common-aperture design, and the common-aperture array layout can face the mutual influence of a radar and a telemetering antenna, so that the ultralow side lobe performance of the radar antenna is deteriorated; the optimal unit spacing non-integral multiple relation of radar and telemetering adopts a common antenna unit design, and the telemetering antenna has the problem of too many units or too large unit spacing; the usable area of each unit is reduced, so that the efficiency of the antenna unit is low, the mutual coupling is enhanced, and the design difficulty of the unit is increased; the calibration network cannot be integrated on the antenna array surface, and the like. The layout of the array surface needs to comprehensively consider in many aspects such as index requirements, sizes, unit arrangement forms and connection modes of rear-end equipment of the two sets of thunder/remote antennas, and the most reasonable arrangement mode is selected, so that the influence between the two sets of antennas can be reduced to the maximum extent, and the comprehensive advantage of the radio frequency aperture can be fully exerted. Therefore, the common aperture layout is a technical difficulty of the present invention.
Second, unit type selection and design
The antenna units are important factors for forming the array antenna, and the performance of the antenna units directly influences the performance of the whole antenna subsystem. The type selection and design of the antenna unit mainly depend on the requirements of the system on the telecommunication performance, structure, electromagnetic compatibility and the like of the antenna unit, and therefore, the type selection and design of the antenna unit are the technical difficulties of the invention.
Third, the passive intermodulation problem of the antenna
By adopting a radar/remote measurement common-aperture design, the antenna units are compactly arranged, so that the isolation of the two sets of antennas is greatly reduced, the passive intermodulation influence of the antennas is more serious, and the passive intermodulation of the antennas becomes one of important interference sources and needs to be suppressed. Therefore, it is a technical difficulty of the present invention to reduce the passive intermodulation of the antenna.
How to overcome the technical difficulties is the problem to be solved by the invention, so as to realize the design idea that two sets of independent antenna array surfaces adopt radio frequency aperture synthesis.
Disclosure of Invention
In view of the above, the invention provides an airborne radar and telemetry integrated array antenna, which can solve the problems of radar/telemetry common-aperture layout, antenna unit selection and design and antenna passive intermodulation, realize radar/telemetry multiband, multi-polarization, common-aperture and integrated cooperative work in an airborne environment, and improve the utilization rate and integration level of an antenna aperture.
In order to achieve the purpose, the technical scheme of the invention is as follows:
the integrated array antenna consists of a common antenna unit, wherein the common antenna unit consists of a horizontal polarization unit and a vertical polarization unit which share the same aperture.
The horizontal polarization unit covers radar and telemetry frequency bands.
The n common antenna units form a sub-array, all horizontal polarization units in each sub-array are connected with radar channels, every other common antenna unit serves as a telemetering unit, and the horizontal polarization units and the vertical polarization units in the telemetering units are respectively connected with one telemetering channel.
Furthermore, a horizontal polarization unit in the telemetry unit is divided into two parts through a duplexer and is respectively connected with the radar channel and the telemetry channel.
Further, the height of the antenna is 2/3 of the conventional orthogonal gradient slot antenna, the thickness of the microstrip board is one layer, and the connection structure between the common antenna units is removed.
Further, the common antenna units are connected by a radio frequency connector, which is a low intermodulation connector. The low intermodulation connector passive intermodulation is below-150 dBm.
Furthermore, all metal structural members related to the antenna on the antenna array surface of the co-antenna unit are subjected to conductive oxidation or coating treatment, and the antenna unit microstrip board is subjected to gold plating treatment.
Has the advantages that:
1. in the invention, the radar and the remote measurement adopt a common-aperture design of a horizontal polarization unit and a vertical polarization unit. The horizontal polarization unit adopts a broadband antenna to cover radar and a telemetering frequency band, the vertical polarization unit is designed to be the same as the horizontal polarization unit, the antenna units are arranged in a rectangular grid in a rectangular cutting shape, two antennas are vertically placed to form double linear polarization, the horizontal polarization unit is divided into two parts through a duplexer and is respectively connected with a telemetering channel and a radar channel, and the vertical polarization unit is connected with the other telemetering channel. The two sets of antennas are shielded from each other and have small mutual influence, so that the performance of the two sets of antennas can be fully exerted, and the problem of performance deterioration of the ultralow side lobe of the radar antenna is solved. After the antenna is shared, the number of the telemetering antenna units is large because radar is required to be considered for the unit distance. The invention adopts a sparse array arrangement method, reduces the number of antenna units under the conditions of ensuring the antenna performance and reducing the cost, wherein the radar antenna units adopt a full array, and the remote measurement adopts a sparse array arrangement scheme.
2. The invention adopts the orthogonal gradual change slot antenna unit, reduces the height of the antenna to about 2/3 of the conventional orthogonal gradual change slot antenna by changing the form of the gradual change slot, and changes the thickness of the microstrip board into one layer, thereby greatly reducing the size and the weight of the antenna. Meanwhile, the connecting structure between the antenna units is removed, so that the antenna units are easy to assemble and replace, and the maintainability of the antenna units is improved. The section and the weight of the antenna are reduced, and the stress generated by the vibration deformation and the temperature change of the antenna unit under the impact and the vibration of the airborne environment is reduced. And optimally designing the size of the antenna through simulation software to ensure that good standing wave and directional diagram performance is obtained, and finally shaping the size of the antenna unit.
3. In order to solve the problem of passive intermodulation of the antenna, the invention solves the following aspects: the antenna unit is designed in a light weight mode, and on the premise of ensuring the electrical performance of the antenna unit, the antenna unit is designed in a most simplified structural form, so that the section and the weight of the antenna are reduced, and the stress generated by vibration deformation and temperature change of the antenna unit under the impact and vibration of an airborne environment is reduced; the radio frequency connector of the antenna unit in the invention is a low intermodulation connector; in the invention, all metal structural members related to the antenna on the antenna array surface are subjected to conductive oxidation or coating treatment, and the antenna unit microstrip board is subjected to gold plating treatment.
Drawings
Fig. 1 is a schematic diagram of a common antenna unit of an airborne radar and telemetry integrated array antenna provided by an embodiment of the invention; in the figure, 1 is a horizontal polarization unit, 2 is a vertical polarization unit, 3 is a microstrip plate, 4 is a reflecting plate, 5 is an antenna connecting mechanism, and 6 is an antenna slot;
fig. 2 is a schematic arrangement diagram of a co-antenna unit of an airborne radar and telemetry integrated array antenna provided by an embodiment of the invention.
Detailed Description
The invention is described in detail below by way of example with reference to the accompanying drawings.
The invention provides an airborne radar and telemetering integrated array antenna, which consists of a common antenna unit, wherein the common antenna unit consists of a horizontal polarization unit and a vertical polarization unit which share an aperture; as shown in fig. 1. In the figure, 1 is a horizontal polarization unit, 2 is a vertical polarization unit, 3 is a microstrip plate, 4 is a reflection plate, 5 is an antenna connection mechanism, and 6 is an antenna slot.
The horizontal polarization unit covers radar and a telemetering frequency band;
the n common antenna units form a sub-array, all horizontal polarization units in each sub-array are connected with radar channels, every other common antenna unit serves as a telemetering unit, and the horizontal polarization units and the vertical polarization units in the telemetering units are respectively connected with one telemetering channel.
The horizontal polarization unit in the telemetering unit is divided into two parts by a duplexer and is respectively connected with a radar channel and a telemetering channel.
In the invention, the radar and the remote measurement adopt a horizontal polarization common antenna unit and a remote measurement vertical polarization unit common aperture design. The horizontal polarization unit adopts a broadband antenna to cover radar and a telemetering frequency band, the vertical polarization unit is designed to be the same as the horizontal polarization unit, the antenna units are arranged in a rectangular grid in a rectangular cutting shape, two antennas are vertically placed to form double linear polarization, the horizontal polarization unit is divided into two parts through a duplexer and is respectively connected with a telemetering channel and a radar channel, and the vertical polarization unit is connected with the other telemetering channel. The two sets of antennas are shielded from each other and have small mutual influence, so that the performance of the two sets of antennas can be fully exerted, and the problem of performance deterioration of the ultralow side lobe of the radar antenna is solved.
After the antenna is shared, the number of the telemetering antenna units is large because radar is required to be considered for the unit distance. The invention adopts a sparse arrangement method, and reduces the number of antenna units under the conditions of ensuring the performance of the antenna and reducing the cost. The invention takes 16 radar units as a sub-array, wherein the radar antenna units adopt a full array, the telemetering adopts a sparse array arrangement scheme, the units are uniformly arranged in two forms, namely 1, 3, 5, 7, 9, 11, 13 and 15 units are respectively connected with telemetering and 2, 4, 6, 8, 10, 12, 14 and 16 units are connected with telemetering, as shown in figure 2. The grating lobes in the telemetry scanning space can be eliminated by the random arrangement of the two sub-arrays.
The invention selects the orthogonal gradient slot antenna unit and makes an improved design for the orthogonal gradient slot antenna unit, as shown in figure 1. By changing the form of the gradient slot, the height of the antenna is reduced to about 2/3 of the conventional orthogonal gradient slot antenna, and the thickness of the microstrip board is changed into one layer, so that the size and the weight of the antenna are greatly reduced. Meanwhile, the connecting structure between the antenna units is removed, so that the antenna units are easy to assemble and replace, and the maintainability of the antenna units is improved. The section and the weight of the antenna are reduced, and the stress generated by the vibration deformation and the temperature change of the antenna unit under the impact and the vibration of the airborne environment is reduced. And optimally designing the size of the antenna through simulation software to ensure that good standing wave and directional diagram performance is obtained, and finally shaping the size of the antenna unit.
Aiming at the problem of passive intermodulation of the antenna, the invention adopts the following aspects that on one hand, the common antenna units are connected through a radio frequency connector, and the radio frequency connector is a low intermodulation connector. According to the system requirement, the passive intermodulation of the connector is lower than-150 dBm, and the passive intermodulation value of the general connector is about-100 dBm. On the other hand, all metal structural members related to the antenna on the antenna array surface of the co-antenna unit are subjected to conductive oxidation or coating treatment, and the antenna unit microstrip plate is subjected to gold plating treatment. In addition, in the manufacturing process, the control of the metal compression joint surface is enhanced, metal compression joint structures are adopted between the microstrip plate and the metal support lug and between the metal support lug and the antenna reflection plate, the metal compression joint surface is required to be flat, smooth and clean, the pressing force needs to be controlled, and the reliable contact is ensured. The generation of metal chips is strictly controlled in the production, assembly and test processes.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (5)

1. An airborne radar and telemetering integrated array antenna is characterized in that the integrated array antenna is composed of a common antenna unit, wherein the common antenna unit is composed of a horizontal polarization unit and a vertical polarization unit which share an aperture;
the horizontal polarization unit covers radar and a telemetry frequency band; the vertical polarization unit is designed to be the same as the horizontal polarization unit, the antenna units are arranged in a rectangular grid in a rectangular cutting shape, and the two antennas are vertically placed to form double linear polarization;
the n common antenna units form a sub-array, all horizontal polarization units in each sub-array are connected with radar channels, every other common antenna unit serves as a telemetering unit, and the horizontal polarization units and the vertical polarization units in the telemetering units are respectively connected with one telemetering channel.
2. The antenna of claim 1, wherein a horizontally polarized section of the telemetry unit is split into two sections by a duplexer into a radar channel and a telemetry channel.
3. The antenna of claim 1, wherein the antenna height is 2/3 for a conventional orthogonally tapered slot antenna, the microstrip plate thickness is one layer, and the connection structure between the common antenna elements is removed.
4. The antenna of claim 1, wherein the co-antenna units are connected by a radio frequency connector, the radio frequency connector being a low intermodulation connector, the low intermodulation connector having passive intermodulation below-150 dBm.
5. The antenna of claim 1, wherein all of the metallic structures associated with the antenna on the antenna array of the co-antenna element are conductively oxidized or plated and the microstrip plate of the antenna element is gold plated.
CN201910236201.4A 2019-03-27 2019-03-27 Airborne radar and telemetering integrated array antenna Expired - Fee Related CN110112541B (en)

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CN110112541B true CN110112541B (en) 2021-01-15

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EP4346119A1 (en) 2022-09-28 2024-04-03 Joanneum Research Forschungsgesellschaft mbH Method and apparatus for communicating telemetry data between an airborne vehicle and a ground station

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CN201130715Y (en) * 2007-12-18 2008-10-08 京信通信系统(中国)有限公司 Multisystem community antenna
CN101364672A (en) * 2008-09-17 2009-02-11 中国电子科技集团公司第三十八研究所 Wideband dual-linear polarization bipole antenna array
CN106099395A (en) * 2016-08-11 2016-11-09 成都雷电微力科技有限公司 A kind of multifrequency Shared aperture is combined phased array antenna structure
CN109478720A (en) * 2016-09-08 2019-03-15 康普技术有限责任公司 High performance flat antenna for double frequency-band, broadband and bipolar operation

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