A plane wave generator based on Luneburg lens

Abstract

The invention discloses a plane wave generator based on a Luneburg lens, comprising a Luneburg lens and a feed source, wherein the Luneburg lens is arranged between mutually parallel metal plates, and the feed source comprises a dipole antenna, and the dipole antenna is inserted between the mutually parallel metal plates. The invention can generate a stable plane wave within a short distance, and is suitable for application in microwave measurement darkrooms and dark boxes.

Description

Technical Field

[0001] The present invention relates to the field of microwave technology, and in particular to a plane wave generator. Background Art

[0002] With the widespread application of millimeter-wave terahertz technology in microwave radio frequency, remote sensing, telemetry, security inspection, medical and other fields, the demand for accurate measurement of the performance of millimeter-wave terahertz antennas is becoming more and more urgent.

[0003] The existing compact fields applicable to millimeter-wave terahertz include three basic types: reflective surface type, lens type, and holographic compact field. In recent years, research on array antennas has also been added.

[0004] The lens compact field generally uses one or two reflector antennas, and the accuracy of the reflector surface should be better than λ / 100. For example, when a 100GHz test is required, the reflector surface accuracy of the reference reflector antenna is required to be as high as 30μm. Therefore, as the frequency band increases, one method is to use a lens-type reference antenna. The surface accuracy requirement of the lens is lower than that of the reflector, and the phase error is also better than that of the reflector. Another method is the holographic compact field, which uses a corresponding new type of holographic reflector as a reference antenna. The main structure is a corresponding planar holographic structure as a collimator to convert the spherical wave emitted by the feed horn into a plane wave.

[0005] At present, the reflective surface and lens of the above-mentioned compact field reference antenna are large in size and costly, and the construction scale and location requirements of the compact field are high. The bandwidth of the holographic compact field is very narrow due to the diffraction of the holographic film itself, and the cross-polarization is also poor, which cannot meet the requirements of broadband millimeter wave testing. Summary of the invention

[0006] The present invention aims to provide a plane wave generator based on a Luneburg lens, which can generate stable plane waves in a short distance and is suitable for application in microwave measurement darkrooms and darkboxes.

[0007] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0008] The invention discloses a plane wave generator based on a Luneburg lens, comprising a Luneburg lens and a feed source, wherein the Luneburg lens is arranged between mutually parallel metal plates, and the feed source comprises a dipole antenna, and the dipole antenna is inserted between the mutually parallel metal plates.

[0009] Furthermore, there are at least three metal plates, which are stacked and arranged in parallel, Luneburg lenses are provided between adjacent metal plates, dipole antennas are inserted between adjacent metal plates, and all dipole antennas constitute a dipole antenna array.

[0010] Furthermore, the feed source also includes a power division network, and the power division network is connected to the dipole antenna array.

[0011] Preferably, the Luneburg lens is made of plastic.

[0012] Preferably, the dipole antenna is a double-sided printed dipole antenna, the double-sided printed dipole antenna comprises a double-sided printed circuit board, the double-sided printed circuit board is perpendicular to the metal plate, and the double-sided printed dipole antenna is located in the middle of the metal plate.

[0013] Preferably, the metal plate is provided with a notch for inserting the double-sided printed circuit board, or the double-sided printed circuit board is provided with a notch for avoiding the metal plate.

[0014] Furthermore, plastic fillers are filled between adjacent metal plates to fix the Luneburg lenses and support the metal plates.

[0015] Furthermore, all the metal plates are detachably connected via a connecting mechanism.

[0016] Preferably, the connection mechanism is a bolt connection mechanism, and the bolt passes through the metal plate and is fastened by a nut.

[0017] Furthermore, the present invention also includes a bottom plate, the top surface of the bottom plate is in contact with the bottom surface of the metal plate at the bottom, and the bolts pass through the bottom plate.

[0018] The working principle of the present invention is as follows:

[0019] The electromagnetic waves generated by the feed source can form a stable plane wave that radiates forward through parallel metal plates and arc-shaped Luneburg lenses; through multi-layer superposition, a stable plane electromagnetic wave can be formed, and finally a stable quiet zone can be formed.

[0020] The beneficial effects of the present invention are as follows:

[0021] 1. The present invention can generate stable plane waves within a short distance and is suitable for use in microwave measurement darkrooms and darkboxes.

[0022] 2. The present invention can realize the miniaturization of the plane wave generator.

[0023] 3. The feed source of the present invention is formed by a double-sided dipole antenna plus a feeding network, and both are broadband antennas like the Luneburg lens, with a wide bandwidth, which reduces the need to replace the reference antenna during testing.

[0024] 4. Compared with complete lens and reflector antennas, the present invention has small size, light weight, low cost and easy installation.

[0025] 5. The present invention can form a stable quiet zone within a distance of 2 to 5 times the wavelength.

[0026] 6. The size of the quiet zone formed by the present invention can be adjusted by the number of stacked layers of multi-layer metal plates. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of the present invention.

[0028] Figure 2 It is a schematic diagram of the principle of the present invention.

[0029] Figure 3 This is a schematic diagram of the local installation of the feed source. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0031] Example 1

[0032] This embodiment discloses a plane wave generator based on Luneburg lens, which is composed of a feed source, parallel metal plates, Luneburg lenses and mounting structural parts. The arc-shaped partial Luneburg lens is fixed in the middle of the parallel metal plates. The Luneburg lens is made of plastic and is completed by 3D printing. The electromagnetic wave generated by the feed source can form a stable plane wave radiating forward through the parallel metal plates and the arc-shaped Luneburg lens. The feed source is a printed dipole antenna array. A stable plane electromagnetic wave can be formed by multi-layer superposition, and finally a stable quiet zone is formed.

[0033] Plastic fillers are used between the multiple metal plates to fix the Luneburg lenses and provide support for the parallel metal plates.

[0034] Specifically, Figure 1 As shown, this embodiment includes a Luneburg lens and a feed source 3. The Luneburg lens and the plastic filler 2 are arranged between mutually parallel metal plates 1. The Luneburg lens is made of plastic and is completed by 3D printing. The feed source 3 includes a dipole antenna. The dipole antenna is inserted between mutually parallel metal plates 1. The double-sided printed dipole antenna is located in the middle of the metal plate 1.

[0035] The above structure is stacked in multiple layers, that is, Luneburg lenses are arranged between adjacent metal plates 1, and dipole antennas are inserted between adjacent metal plates 1, and the dipole antennas constitute a dipole antenna array; the feed source 3 also includes a power division network, and the power division network is connected to the dipole antenna array.

[0036] All metal plates are detachably connected via a connecting mechanism. This embodiment also includes a bottom plate 4, the top surface of which is in contact with the bottom surface of the metal plate 1 at the bottom. The connecting mechanism is a bolt connecting mechanism, and the bolts 11 pass through the metal plate 1 and the bottom plate 4 and are fastened by nuts.

[0037] like Figure 2As shown, a stable plane electromagnetic wave 5 can be formed by multi-layer superposition, and finally a stable quiet zone can be formed.

[0038] Example 2

[0039] This embodiment discloses a structure of a feed source part based on the embodiment 1, specifically as follows: Figure 3 As shown, the dipole antenna of the feed source 3 is a double-sided printed dipole antenna, which includes a double-sided printed circuit board 31 and a printed antenna 32 attached to the substrate of the double-sided printed circuit board 31. The double-sided printed circuit board 31 is perpendicular to the metal plate 1, and the double-sided printed circuit board 31 is located in the middle of the metal plate 1.

[0040] The metal plate 1 is provided with a notch for inserting the double-sided printed circuit board 31, or the double-sided printed circuit board 31 is provided with a notch 33 for avoiding the metal plate.

[0041] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A plane wave generator based on a Luneburg lens, characterized in that: It comprises a Luneburg lens and a feed source, wherein the Luneburg lens is arranged between mutually parallel metal plates, and the feed source comprises a dipole antenna, and the dipole antenna is inserted between the mutually parallel metal plates; There are at least three metal plates, which are stacked and arranged in parallel, Luneburg lenses are arranged between adjacent metal plates, dipole antennas are inserted between adjacent metal plates, and all dipole antennas constitute a dipole antenna array; The dipole antenna is a double-sided printed dipole antenna, which includes a double-sided printed circuit board, the double-sided printed circuit board is perpendicular to the metal plate, and the double-sided printed dipole antenna is located in the middle of the metal plate; The plane wave generator is suitable for use in microwave measurement darkrooms and dark boxes, and forms a stable plane electromagnetic wave through multi-layer superposition, and finally forms a stable quiet zone.

2. The plane wave generator based on Luneburg lens according to claim 1, characterized in that: The feed source also includes a power division network, which is connected to the dipole antenna array.

3. The plane wave generator based on Luneburg lens according to claim 1, characterized in that: The Luneburg lens is made of plastic.

4. The plane wave generator based on Luneburg lens according to claim 1, characterized in that: The metal plate is provided with a notch for inserting the double-sided printed circuit board, or the double-sided printed circuit board is provided with a notch for avoiding the metal plate.

5. The plane wave generator based on Luneburg lens according to claim 1, characterized in that: Plastic fillers are filled between adjacent metal plates to fix the Luneburg lenses and support the metal plates.

6. The plane wave generator based on Luneburg lens according to claim 5, characterized in that: All metal plates are detachably connected via a connecting mechanism.

7. The plane wave generator based on Luneburg lens according to claim 6, characterized in that: The connection mechanism is a bolt connection mechanism, and the bolt passes through the metal plate and is fastened by a nut.

8. The plane wave generator based on Luneburg lens according to claim 7, characterized in that: It also includes a bottom plate, the top surface of the bottom plate is in contact with the bottom surface of the metal plate at the bottom, and the bolts pass through the bottom plate.

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