Multiband integrated antenna applied to airborne temperature and humidity profiler

Abstract

The utility model discloses a multiband integrated antenna applied to an airborne temperature and humidity profiler, and the integrated antenna comprises a main reflection surface, the projection clear aperture of the main reflection surface employs a 90-degree off-axis paraboloid design, an incident wave beam is perpendicular to the rotation axis of the main reflection surface, and a convergent wave beam is generated after parallel light is received; the four-waveband quasi-optical feed point network is composed of a first-stage frequency selection surface and a second-stage frequency selection surface, and the first-stage frequency selection surface receives the convergent wave beams generated by the main reflection surface and transmits the wave beams to the second-stage frequency selection surface; according to the multi-band common-aperture antenna integration technology, a compact optical layout design is adopted, system envelope as small as possible can be achieved, and the requirement for the small size of an airborne platform is met; the frequency divider adopts frequency selection surfaces in a quasi-optical form, and the separation of four working frequency bands is realized through the combined use of the three frequency selection surfaces; and a modular design is adopted, so that the debugging difficulty is reduced, and the system maintainability is improved.

Description

Technical Field

[0001] This utility model belongs to the field of microwave radiometer technology, specifically relating to a multi-band integrated antenna used in airborne temperature and humidity profilers. Background Technology

[0002] Airborne temperature and humidity profilers are primarily used for atmospheric remote sensing beneath flight paths. They passively detect atmospheric radiation information in the V-band (51–59 GHz) and F-band (113–120 GHz) of the oxygen channel, the G-band (173–183 GHz) of the water vapor channel, and the W-band of the window region to remotely sense and retrieve parameters such as atmospheric temperature and humidity profiles beneath flight paths. Multi-band antennas are the core subsystem of airborne temperature and humidity profilers, and their performance directly determines the profiler's detection accuracy. There are currently no reports of finished airborne temperature and humidity profilers in China. Most foreign airborne profilers use a single band with a fixed single reflector, resulting in a large size when there are multiple bands, which cannot meet the small size requirements of airborne platforms and cannot achieve angle scanning. Therefore, a common-aperture antenna integration technology needs to be considered to share a single reflector for multiple band antennas, overcoming the disadvantages of large size and fixed beam of single-band single reflectors. Utility Model Content

[0003] The purpose of this invention is to provide a multi-band integrated antenna for airborne temperature and humidity profilers, in order to solve the problem mentioned in the background art that airborne temperature and humidity profilers have many operating bands and corresponding antenna horns and reflectors.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a multi-band integrated antenna for an airborne temperature and humidity profiler, comprising a main reflector with a projected light-passing aperture, a 90° off-axis parabolic design, an incident beam perpendicular to the rotation axis of the main reflector, and a converging beam generated after receiving parallel light; a four-band quasi-optical feed network, consisting of a first-level frequency selective surface and a second-level frequency selective surface, wherein the first-level frequency selective surface receives the converging beam generated by the main reflector and transmits the beam to the second-level frequency selective surface; atmospheric radiation energy passes through the radome, is received by the main reflector, and then the transmission direction is changed by the main reflector; the quasi-optical feed network achieves separation of the four operating frequency bands (V / W / F / G) through the combined use of three high-pass frequency selective surfaces.

[0005] In a preferred embodiment of this invention, the primary frequency selective surface is divided into a V / W frequency selective surface for reflected beams and an F / G frequency selective surface for transmitted beams. The V / W frequency selective surface, after passing through a secondary frequency selective surface, is divided into the V band and the W band, while the F / G frequency selective surface, after passing through a secondary frequency selective surface, is divided into the F band and the G band. The multi-band multiplexing function is achieved through a quasi-optical frequency selective surface (FSS). For an array aperture FSS, each aperture can be considered a small waveguide segment. When the frequency of the incident plane wave is below the waveguide cutoff frequency, most of the plane wave energy is reflected; when the frequency of the incident plane wave is above the cutoff frequency, most of the incident energy is transmitted, thus serving as a high-pass filter. In this antenna system, atmospheric radiation energy passes through the radome, is received by the primary reflector, and then the transmission direction is changed by the primary reflector. The quasi-optical feed network achieves separation of the four operating frequency bands (V / W / F / G) through the combined use of three high-pass frequency selective surfaces.

[0006] As a preferred technical solution of this utility model, G-band feed horns, F-band feed horns, V-band feed horns, and W-band feed horns are respectively provided on the G-band, F-band, V-band, and W-band feed horns. The feed horns determine the antenna aperture field distribution and the polarization mode of the final radiated beam. By shaping and optimizing the inner wall contour of the circular horn, precise control of different waveguide excitation modes can be achieved, thereby obtaining an ideal radiation pattern and excellent port VSWR characteristics. At the same time, the processing difficulty and cycle are greatly reduced compared with traditional corrugated horns. F-band ellipsoidal reflectors are provided on the G-band and F-band, V-band ellipsoidal reflectors are provided on the V-band, and W-band ellipsoidal reflectors are provided on the W-band. The beams of the F-band, V-band, and W-band feed horns are refocused by the F-band feed horns, V-band feed horns, and W-band feed horns, respectively, and then received by the F-band feed horns, V-band feed horns, and W-band feed horns.

[0007] As a preferred technical solution of this utility model, a W-band plane mirror for realizing optical path deflection is configured in front of the W-band feed horn.

[0008] In a preferred embodiment of this invention, the main reflector is mounted on a rotary motor of the antenna servo unit via a main surface support structure. The motor drives the main reflector to rotate around the main optical axis to achieve antenna beam scanning. The mirror mount and the substrate are precisely positioned by pins.

[0009] As a preferred technical solution of this utility model, each quasi-optical element is fixed on the same substrate by an independent lens mount, and the substrate also serves as a reference surface for the installation and positioning of each quasi-optical element.

[0010] As a preferred technical solution of this utility model, the W-band plane reflector and the W-band ellipsoidal reflector are misaligned and the W-band ellipsoidal reflector receives the beam of the W-band ellipsoidal reflector.

[0011] Compared with the prior art, the beneficial effects of this utility model are:

[0012] 1. The multi-band common aperture antenna integration technology of this utility model adopts a compact optical layout design, which can achieve the smallest possible system envelope and is suitable for the small size requirements of airborne platforms;

[0013] 2. The frequency divider uses a quasi-optical frequency selection surface. By combining three frequency selection surfaces, the separation of four operating frequency bands can be achieved.

[0014] 3. A zoom mirror is placed in front of the feed horn for each band so that the beam of the incident frequency selection surface is as close as possible to a plane wave.

[0015] 4. The modular design reduces debugging difficulty and improves system maintainability. Attached Figure Description

[0016] Figure 1 This is a layout diagram of the optical path design for the multi-band common aperture integrated antenna of this utility model;

[0017] Figure 2 This is a structural diagram of the multi-band common aperture integrated antenna of this utility model.

[0018] In the picture:

[0019] 1. V / W frequency selective surface; 2. VW / FG frequency selective surface; 3. F / G frequency selective surface; 4. G-band feed horn; 5. F-band feed horn; 6. V-band feed horn; 7. W-band feed horn;

[0020] M1, main reflecting surface; M2, V-band ellipsoidal reflector; M3, W-band ellipsoidal reflector; M4, F-band ellipsoidal reflector; M5, W-band plane reflector. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] Please see Figure 1 and Figure 2This utility model provides a technical solution: a multi-band integrated antenna for use in an airborne temperature and humidity profiler, the integrated antenna comprising...

[0023] A primary reflector M1 has a projection aperture of 100mm and adopts a 90° off-axis parabolic design. The incident beam is perpendicular to the rotation axis of the primary reflector M1 and generates a converging beam after receiving parallel light.

[0024] The four-band quasi-optical feed network consists of a primary frequency selective surface and a secondary frequency selective surface. The primary frequency selective surface receives the converged beam generated by the main reflector M1 and transmits the beam to the secondary frequency selective surface. Atmospheric radiation energy passes through the radome, is received by the main reflector M1, and then changes the transmission direction through the main reflector M1. The quasi-optical feed network achieves separation of the four operating frequency bands V / W / F / G through the combined use of three high-pass frequency selective surfaces.

[0025] In this embodiment, the primary frequency selective surface, also known as the VW / FG frequency selective surface 2, is divided into a V / W frequency selective surface 1 for reflected beams and an F / G frequency selective surface 3 for transmitted beams. After passing through a secondary frequency selective surface, the V / W frequency selective surface 1 is divided into the V band and the W band, while the F / G frequency selective surface 3 is divided into the F band and the G band. The multi-band multiplexing function is achieved through a quasi-optical frequency selective surface (FSS). For an array aperture FSS, each aperture can be considered as a small waveguide segment. When the frequency of the incident plane wave is below the waveguide cutoff frequency, most of the plane wave energy is reflected; when the frequency of the incident plane wave is above the cutoff frequency, most of the incident energy is transmitted, thus it can act as a high-pass filter. In this antenna system, atmospheric radiation energy passes through the radome, is received by the primary reflector, and then the transmission direction is changed by the primary reflector. The quasi-optical feed network achieves the separation of the four operating frequency bands (V / W / F / G) through the combined use of three high-pass frequency selective surfaces.

[0026] In this embodiment, G-band feed horn 4, F-band feed horn 5, V-band feed horn 6, and W-band feed horn 7 are respectively installed on the G-band, F-band, V-band, and W-band frequency bands. The feed horn determines the antenna aperture field distribution and the polarization of the final radiated beam. By shaping and optimizing the inner wall contour of the circular horn, precise control of different waveguide excitation modes can be achieved, thereby obtaining an ideal radiation pattern and excellent port VSWR characteristics, while reducing manufacturing difficulty and... The period is significantly reduced compared to traditional corrugated horns. F-band ellipsoidal reflectors M4 are installed on the G and F bands, V-band ellipsoidal reflectors M2 are installed on the V band, and W-band ellipsoidal reflectors M3 are installed on the W band. The beams of the F, V, and W bands are refocused by F-band feed horn 5, V-band feed horn 6, and W-band feed horn 7, respectively, and then received by F-band feed horn 5, V-band feed horn 6, and W-band feed horn 7, respectively.

[0027] In this embodiment, a W-band planar reflector M5 for optical path deflection is configured in front of the W-band feed horn 7.

[0028] In this embodiment, the main reflector M1 is mounted on the rotary motor of the antenna servo unit through the main surface support structure. The motor drives the main reflector M1 to rotate around the main optical axis to realize antenna beam scanning. The mirror mount and the substrate are precisely positioned by pins.

[0029] In this embodiment, each quasi-optical element is fixed on the same substrate by an independent lens mount, and the substrate also serves as a reference surface for the installation and positioning of each quasi-optical element.

[0030] In this embodiment, the W-band planar reflector M5 and the W-band ellipsoidal reflector M3 are misaligned and receive the beam from the W-band ellipsoidal reflector M3.

[0031] Although embodiments of the present invention have been shown and described (see the detailed description above), it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A multi-band integrated antenna for use in an airborne temperature and humidity profiler, characterized in that: The integrated antenna includes A primary reflector (M1) is used, with the incident beam perpendicular to the rotation axis of the primary reflector (M1), and it generates a converging beam after receiving parallel light. A four-band quasi-optical feed point network consists of a first-level frequency selective surface and a second-level frequency selective surface. The first-level frequency selective surface receives the converged beam generated by the main reflector (M1) and transmits the beam to the second-level frequency selective surface.

2. The multi-band integrated antenna for an airborne temperature and humidity profiler according to claim 1, characterized in that: The primary frequency selective surface is divided into a V / W frequency selective surface (1) for reflected beams and an F / G frequency selective surface (3) for transmitted beams. The V / W frequency selective surface (1) is divided into V band and W band after passing through the secondary frequency selective surface, while the F / G frequency selective surface (3) is divided into F band and G band after passing through the secondary frequency selective surface.

3. A multi-band integrated antenna for an airborne temperature and humidity profiler according to claim 2, characterized in that: The G-band, F-band, V-band, and W-band frequency bands are respectively equipped with G-band feed horn (4), F-band feed horn (5), V-band feed horn (6), and W-band feed horn (7). The G-band and F-band frequency bands are equipped with F-band ellipsoidal reflectors (M4), the V-band frequency band is equipped with a V-band ellipsoidal reflector (M2), and the W-band frequency band is equipped with a W-band ellipsoidal reflector (M3). The beams of the F-band, V-band, and W-band frequency bands are refocused by the F-band feed horn (5), V-band feed horn (6), and W-band feed horn (7) respectively, and then received by the F-band feed horn (5), V-band feed horn (6), and W-band feed horn (7).

4. A multi-band integrated antenna for an airborne temperature and humidity profiler according to claim 3, characterized in that: The W-band feed horn (7) is equipped with a W-band plane mirror (M5) for optical path reversal.

5. A multi-band integrated antenna for an airborne temperature and humidity profiler according to claim 1, characterized in that: The main reflector (M1) is mounted on the rotary motor of the antenna servo unit via a main reflector support structure, and the motor drives the main reflector (M1) to rotate around the main optical axis.

6. A multi-band integrated antenna for an airborne temperature and humidity profiler according to claim 5, characterized in that: Each quasi-optical element is fixed on the same substrate by an independent lens mount, which also serves as a reference surface for the installation and positioning of each quasi-optical element.

7. A multi-band integrated antenna for an airborne temperature and humidity profiler according to claim 4, characterized in that: The W-band plane mirror (M5) is offset from the W-band ellipsoidal mirror (M3) and receives the beam from the W-band ellipsoidal mirror (M3).

Images