A step defocusing lens that can increase beam width

Abstract

The invention discloses a step defocusing lens capable of increasing beam width. The step defocusing lens is sleeved on the mouth of a circularly polarized horn antenna and is used for increasing the beam width of the horn antenna. The step defocusing lens consists of a central lens and a cylindrical lens surrounding the central lens and integrally connected with the central lens. The central lens is arranged close to the mouth of the horn antenna and is in the inner cavity of the cylindrical lens, and the central lens and the cylindrical lens are coaxially arranged. The inner cavity of the cylindrical lens is divided into an inner cavity and an outer cavity by the central lens. The invention adjusts the antenna standing wave by adjusting the diameter and height of each shaft segment of the cylindrical lens, and further reduces the antenna standing wave through each cavity, thereby reducing reflection and improving the axial ratio of the antenna.

Description

Technical Field

[0001] The invention belongs to the peripheral field of horn antennas, and in particular relates to a stepped defocusing lens capable of increasing beam width. Background Art

[0002] With the development of today's technology, the movement range of terminal equipment is getting wider and wider, the radiation range requirements for transmitting antennas are getting higher and higher, and the demand for ultra-wide beam antennas is also increasing.

[0003] Traditional methods of realizing ultra-wide beam antennas include dipole antennas and their derivative antennas, helical antennas, microstrip patch antennas, metal-loaded horn antennas, etc., but these antennas are accompanied by their own limitations. For example, the bandwidth of dipole antennas is insufficient, the beam width of log-periodic antennas is not wide enough, the power capacity of microstrip patch antennas is low, and metal-loaded horn antennas can only achieve linear polarization, etc. Therefore, these antennas cannot achieve circular polarization, low axial ratio, and ultra-wide beam.

[0004] Specifically, the existing technology realizes circular polarization wide beam in the following forms:

[0005] 1. The 90° corrugated horn antenna has a simple structure and a large power tolerance, but its beam broadening capability is limited and can only reach about 60°.

[0006] 2. By setting up a helical antenna, although the structure is simple and the cost is low, the beam broadening capability is still limited, similar to a 90° corrugated horn, with a beam width of only 60°.

[0007] 3. By setting up a microstrip patch antenna, although the beam broadening capability is strong and can reach more than 90°, the microstrip patch antenna has a narrow bandwidth and small power capacity.

[0008] 4. By setting up a planar spiral antenna, although the bandwidth is wider and can achieve ten times the frequency, the power capacity of the planar spiral antenna is very low, just like the microstrip patch. Summary of the invention

[0009] The object of the present invention is to provide a stepped defocusing lens capable of increasing beam width, so as to solve the problem that conventional circularly polarized horn antennas cannot achieve circular polarization, low axial ratio and ultra-wide beam.

[0010] The present invention adopts the following technical scheme: a step defocusing lens capable of increasing the beam width, the step defocusing lens is sleeved on the mouth of a circularly polarized horn antenna and is used to increase the beam width of the horn antenna;

[0011] The step defocusing lens is composed of a hollow cylindrical lens and a central lens located in the inner cavity of the cylindrical lens, and the central lens and the cylindrical lens are coaxially arranged and integrally connected;

[0012] The central lens is arranged near the mouth of the horn antenna; the inner cavity of the cylindrical lens is divided into an inner cavity and an outer cavity by the central lens;

[0013] The inner cavity of the cylindrical lens includes a first cavity, a second cavity, a third cavity and a fourth cavity which are coaxially arranged in sequence in a direction from the central lens to the horn antenna opening;

[0014] A first annular cavity is coaxially arranged at the periphery of the outer cavity of the cylindrical lens;

[0015] The cylindrical lens is a stepped axis, and includes a first axis segment, a second axis segment, a third axis segment, a fourth axis segment, and a fifth axis segment which are coaxially arranged in sequence along the radiation direction.

[0016] Furthermore, a second annular cavity is arranged at the periphery of the third cavity, the second annular cavity is communicated with the fourth cavity, and is used to fix the cylindrical lens on the horn mouth.

[0017] Furthermore, a third annular cavity is provided between the third cavity and the second annular cavity.

[0018] Further, the outer diameter of the third shaft segment>the outer diameter of the second shaft segment>the outer diameter of the fourth shaft segment>the outer diameter of the first shaft segment>the outer diameter of the fifth shaft segment.

[0019] Further, the diameter of the fourth cavity>the diameter of the third cavity>the diameter of the outer cavity>the diameter of the second cavity>the diameter of the first cavity.

[0020] Further, the length of the first shaft segment>the length of the third shaft segment>the length of the fourth shaft segment>the length of the fifth shaft segment>the length of the second shaft segment.

[0021] Further, the height of the outer cavity>the height of the fourth cavity>the height of the third cavity>the height of the first cavity>the height of the second cavity.

[0022] Further, the height of the first annular cavity is greater than the height of the second annular cavity and greater than the height of the third annular cavity.

[0023] Further, the width of the second annular cavity is greater than the width of the first annular cavity and greater than the width of the third annular cavity.

[0024] Further, the height of the outer cavity is equal to the height of the first annular cavity.

[0025] The beneficial effects of the present invention are:

[0026] The present invention adjusts the standing wave of the circular polarization antenna by adjusting the diameter and height of each axial segment of the cylindrical lens, and further reduces the standing wave of the circular polarization antenna through each cavity, thereby reducing reflection and improving the axial ratio of the circular polarization antenna;

[0027] The step defocusing lens of the present invention can be equivalent to a circular lens with a thin center and thick sides, that is, a concave lens. The beam passing through the central lens of the present invention has a short passing distance, a short equivalent electrical path, and an advanced phase. The beam passing through the cylindrical lens has a long passing distance, a long equivalent electrical path, and a delayed phase. Therefore, the equiphase plane of the beam presents a state of leading the center and lagging the edge. The beam direction is perpendicular to the equiphase plane, that is, it is dispersed from the center to the two sides. When observed from the far field, the effect of an ultra-wide beam is achieved.

[0028] When the present invention is not used, the beam width of the circularly polarized antenna is ≤60°. After the present invention is used, the beam width of the circularly polarized antenna is ≥120°, and within the large angle range of the beam width, the axial ratio of the circularly polarized antenna does not exceed 3dB, so a hemispherical ultra-large range circularly polarized communication effect can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of the present invention;

[0030] Figure 2 This is the measured standing wave diagram of the antenna in Example 1 of the present invention;

[0031] Figure 3 The measured radiation pattern of the antenna in Example 1 of the present invention at a frequency of 19.5 GHz;

[0032] Figure 4 Measured directional pattern of the antenna in Example 1 of the present invention at a frequency of 20.0 GHz;

[0033] Figure 5 This is the measured radiation pattern of the antenna of Example 1 of the present invention at a frequency of 20.5 GHz.

[0034] Among them: 10, first cavity; 11, second cavity; 12, third cavity; 13, fourth cavity; 14, first annular cavity; 15, first axis segment; 16, second axis segment; 17, third axis segment; 18, fourth axis segment; 19, fifth axis segment; 20, second annular cavity; 21, third annular cavity; 22, central lens; 23, cylindrical lens; 24, inner cavity; 25, outer cavity. DETAILED DESCRIPTION

[0035] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. The "direction" in the present invention is based on the position of the present invention in a certain direction. Figure 1 Description of the trend in the state.

[0037] The present invention discloses a step defocusing lens capable of increasing beam width, such as Figure 1 As shown, the step defocusing lens is mounted on the mouth of the circularly polarized horn antenna and is used to increase the beam width of the horn antenna; the step defocusing lens is composed of a central lens 22 and a cylindrical lens 23 surrounding the central lens 22 and integrally connected thereto; that is, the step defocusing lens is composed of a hollow cylindrical lens 23 and a central lens 22 located in the inner cavity of the cylindrical lens 23, and the central lens 22 and the cylindrical lens 23 are coaxially arranged and integrally connected.

[0038] The central lens 22 is arranged near the horn antenna opening and in the inner cavity of the cylindrical lens 23; the inner cavity of the cylindrical lens 23 is divided into an inner cavity 24 and an outer cavity 25 by the central lens 22. The central lens 22 is sheet-shaped and its direction is perpendicular to the axis of the cylindrical lens 23.

[0039] The inner cavity 24 of the cylindrical lens 23 includes a first cavity 10 , a second cavity 11 , a third cavity 12 and a fourth cavity 13 which are coaxially arranged in sequence in a direction from the central lens 22 to the horn antenna opening.

[0040] A first annular cavity 14 is coaxially arranged on the periphery of the outer cavity 25 of the cylindrical lens 23; the cylindrical lens 23 is a stepped axis, which refers to the outer wall structure of the cylindrical lens 23, and the cylindrical lens 23 includes a first axis segment 15, a second axis segment 16, a third axis segment 17, a fourth axis segment 18, and a fifth axis segment 19 coaxially arranged along the radiation direction.

[0041] Preferably, a second annular cavity 20 is disposed at the periphery of the third cavity 12 , the second annular cavity 20 is communicated with the fourth cavity 13 , and is used to fix the cylindrical lens 23 on the horn mouth.

[0042] Preferably, a third annular cavity 21 is further provided between the third cavity 12 and the second annular cavity 20 .

[0043] Preferably, the outer diameter of the third shaft segment 17 is greater than the outer diameter of the second shaft segment 16 , greater than the outer diameter of the fourth shaft segment 18 , greater than the outer diameter of the first shaft segment 15 , and greater than the outer diameter of the fifth shaft segment 19 .

[0044] Preferably, the diameter of the fourth cavity 13 is greater than the diameter of the third cavity 12 , greater than the diameter of the outer cavity 25 , greater than the diameter of the second cavity 11 , and greater than the diameter of the first cavity 10 .

[0045] Preferably, the length of the first shaft segment 15 is greater than the length of the third shaft segment 17 , the length of the fourth shaft segment 18 , the length of the fifth shaft segment 19 , and the length of the second shaft segment 16 .

[0046] Preferably, the height of the outer cavity 25 is greater than the height of the fourth cavity 13 , greater than the height of the third cavity 12 , greater than the height of the first cavity 10 , and greater than the height of the second cavity 11 .

[0047] Preferably, the height of the first annular cavity 14 is greater than the height of the second annular cavity 20 and greater than the height of the third annular cavity 21 .

[0048] Preferably, the width of the second annular cavity 20 is greater than the width of the first annular cavity 14 and greater than the width of the third annular cavity 21 .

[0049] Preferably, the height of the outer cavity 25 is equal to the height of the first annular cavity 14 .

[0050] Preferably, the step defocus lens is made of a non-metallic dielectric material with a dielectric constant of 2.1 to 4.5.

[0051] The present invention sets each cavity and each axis segment, thereby adjusting the thickness of the central lens 22 to one quarter of the medium wavelength. Therefore, after the wave is reflected by the two interfaces, a 180° phase difference is formed to cancel each other out, which can effectively reduce the reflected wave of the step defocusing lens, improve the antenna standing wave, and optimize the axial ratio performance.

[0052] Example 1: A medium with a dielectric constant of 3.0 is used to make a step defocusing lens. The wavelength of the medium is It is 8.6603mm.

[0053] The height of the step defocus lens prepared in this embodiment is 2.3 =19.92mm, where the outer diameters of the third shaft segment 17, the second shaft segment 16, the fourth shaft segment 18, the first shaft segment 15, and the fifth shaft segment 19 are 2.72 respectively. , 2.53 , 2.42 , 1.85 , 1.55 , that is, 23.56 mm, 21.91 mm, 20.96 mm, 16.02 mm, and 13.42 mm respectively.

[0054] The diameter of the fourth cavity 13, the diameter of the third cavity 12, the diameter of the outer cavity 25, the diameter of the second cavity 11, and the diameter of the first cavity 10 are 1.47 respectively. , 0.88 , 0.83 , 0.71 , 0.55 , that is, 12.73 mm, 7.62 mm, 7.19 mm, 6.15 mm, and 4.76 mm respectively.

[0055] The length of the first shaft segment 15, the length of the third shaft segment 17, the length of the fourth shaft segment 18, the length of the fifth shaft segment 19, and the length of the second shaft segment 16 are 0.86 respectively. , 0.69 , 0.34 , 0.32 , 0.09 , that is, 7.45 mm, 5.98 mm, 2.94 mm, 2.77 mm, and 0.78 mm respectively.

[0056] The height of the outer cavity 25, the height of the fourth cavity 13, the height of the third cavity 12, the height of the first cavity 10, and the height of the second cavity 11 are 0.61 respectively. , 0.58 , 0.41 , 0.32 , 0.25 , that is, 5.28 mm, 5.02 mm, 3.55 mm, 2.77 mm, and 2.17 mm respectively.

[0057] The height of the first annular cavity 14, the height of the second annular cavity 20, and the height of the third annular cavity 21 are 0.61 respectively. , 0.32 , 0.16 , which are 5.28 mm, 2.77 mm, and 1.39 mm respectively.

[0058] The width of the second annular cavity 20, the width of the first annular cavity 14, and the width of the third annular cavity 21 are 0.28 respectively. , 0.27 , 0.16 ; That is, 2.42 mm, 2.34 mm, and 1.39 mm respectively.

[0059] like Figure 2 and 3 As shown, the step defocus lens prepared in this embodiment was tested at 19.5 GHz, and the test results are as follows:

[0060] Port: L, Frequency: 19.5GHz

[0061] VSWR: 1.152

[0062] Gain: 5.04dB

[0063] E beam width: -3dB, 130.84°

[0064] H beam width: -3dB, 125.54°

[0065] +60° axial ratio: 2.05dB

[0066] 0° Axis Ratio: 1.34 dB

[0067] -60° axial ratio: 0.69dB.

[0068] like Figure 2 and 4 As shown, the step defocus lens prepared in this embodiment is tested at 20 GHz, and the test results are as follows:

[0069] Port: L, Frequency: 20.0GHz

[0070] VSWR: 1.062

[0071] Gain: 5.18dB

[0072] E beam width: -3dB, 130.57°

[0073] H beam width: -3dB, 123.75°

[0074] +60° axial ratio: 2.49dB

[0075] 0° Axis Ratio: 1.10 dB

[0076] -60° axial ratio: 0.77dB.

[0077] like Figure 2 and 5 As shown, the step defocus lens prepared in this embodiment was tested at 20.5 GHz, and the test results are as follows:

[0078] Port: L, Frequency: 20.5GHz

[0079] VSWR: 1.045

[0080] Gain: 5.17dB

[0081] E beam width: -3dB, 127.38°

[0082] H beam width: -3dB, 128.18°

[0083] +60° axial ratio: 2.67dB

[0084] 0° Axis Ratio: 1.21 dB

[0085] -60° axial ratio: 1.44dB.

[0086] from Figure 3-5 It can be seen that the step defocus lens prepared in this embodiment has a frequency range of 19.5GHz~20.5GHz, a bandwidth of 5%, a standing wave ratio less than 1.16, a gain ≥5dB, a beam width ≥125°, and a beam width inner axis ratio ≤3dB, and the product performance is excellent.

[0087] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A step defocusing lens capable of increasing beam width, characterized in that: The step defocusing lens is mounted on the opening of the circular polarization horn antenna and is used to increase the beam width of the horn antenna; The step defocusing lens is composed of a hollow cylindrical lens (23) and a central lens (22) located in the inner cavity of the cylindrical lens (23); the central lens (22) and the cylindrical lens (23) are coaxially arranged and integrally connected; The central lens (22) is arranged close to the horn antenna opening; the inner cavity of the cylindrical lens (23) is divided into an inner cavity (24) and an outer cavity (25) by the central lens (22); The inner cavity (24) of the cylindrical lens (23) comprises a first cavity (10), a second cavity (11), a third cavity (12) and a fourth cavity (13) which are coaxially arranged in sequence in a direction from the central lens (22) to the horn antenna opening; A first annular cavity (14) is coaxially arranged on the periphery of the outer cavity (25) of the cylindrical lens (23); The cylindrical lens (23) is a stepped axis, and comprises a first axis segment (15), a second axis segment (16), a third axis segment (17), a fourth axis segment (18), and a fifth axis segment (19) which are coaxially arranged in sequence along the radiation direction; By setting each cavity and each shaft segment, the thickness of the central lens (22) is adjusted to one quarter of the wavelength of the medium, so that after the waves are reflected by two interfaces, a phase difference of 180° is formed, thereby canceling each other out.

2. The step defocusing lens capable of increasing beam width according to claim 1, characterized in that: A second annular cavity (20) is arranged on the periphery of the third cavity (12); the second annular cavity (20) is connected to the fourth cavity (13) and is used to fix the cylindrical lens (23) on the horn mouth.

3. The step defocusing lens capable of increasing beam width according to claim 2, characterized in that: A third annular cavity (21) is also provided between the third cavity (12) and the second annular cavity (20).

4. The step defocusing lens capable of increasing beam width according to claim 1, characterized in that: The outer diameter of the third shaft segment (17) is greater than the outer diameter of the second shaft segment (16) is greater than the outer diameter of the fourth shaft segment (18) is greater than the outer diameter of the first shaft segment (15) is greater than the outer diameter of the fifth shaft segment (19).

5. The step defocusing lens capable of increasing beam width according to claim 1, characterized in that: The diameter of the fourth cavity (13) is greater than the diameter of the third cavity (12)> the diameter of the outer cavity (25)> the diameter of the second cavity (11)> the diameter of the first cavity (10).

6. The step defocusing lens capable of increasing beam width according to claim 1, characterized in that: The length of the first shaft segment (15) is greater than the length of the third shaft segment (17) is greater than the length of the fourth shaft segment (18) is greater than the length of the fifth shaft segment (19) is greater than the length of the second shaft segment (16).

7. The step defocusing lens capable of increasing beam width according to claim 1, characterized in that: The height of the outer cavity (25) is greater than the height of the fourth cavity (13) and greater than the height of the third cavity (12) and greater than the height of the first cavity (10) and greater than the height of the second cavity (11).

8. The step defocusing lens capable of increasing beam width according to claim 3, characterized in that: The height of the first annular cavity (14) is greater than the height of the second annular cavity (20) and greater than the height of the third annular cavity (21).

9. The step defocusing lens capable of increasing beam width according to claim 3, characterized in that: The annular width of the second annular cavity (20) is greater than the annular width of the first annular cavity (14) and greater than the annular width of the third annular cavity (21).

10. The step defocusing lens capable of increasing beam width according to claim 3, characterized in that: The height of the outer cavity (25) is equal to the height of the first annular cavity (14).

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