Ultra-wideband equal-gain feed source horn antenna

Abstract

The invention discloses an ultra-wideband equal-gain feed source horn antenna, the frequency range of the horn antenna is 6 GHz-18 GHz, the horn antenna comprises a uniform circular waveguide, a horn-shaped circular waveguide and four ridge waveguides, the uniform circular waveguide and the horn-shaped circular waveguide are integrally connected, and the four ridge waveguides are fixed in a waveguide cavity formed by the uniform circular waveguide and the horn-shaped circular waveguide; the cross section of the trumpet-shaped circular waveguide is gradually increased, and the four ridge waveguides are arranged in the waveguide cavity in a pairwise symmetrical and mutually orthogonal manner; the gain change range of the horn antenna is 9dB to 12dB; the change range of the wave beam width of the electric field surface is 68-39 degrees; the change range of the wave beam width of the magnetic field surface is 68-40 degrees; according to the invention, the ridge waveguide with the gradually-changed index curve and the waveguide cavity with the gradually-changed index are adopted, so that almost constant gain and stable beam width are obtained.

Description

Technical Field

[0001] The invention belongs to the field of microwave radio frequency, and in particular relates to an ultra-wideband equal-gain feed horn antenna. Background Art

[0002] In modern communication technology, ultra-wideband antennas have attracted widespread attention due to their ability to maintain stable performance over a wide frequency range. However, when applied to reflector feeds, traditional ultra-wideband horn antennas have large beam width variations over the frequency range.

[0003] The working principle of the reflector antenna requires the feed to have a stable illumination level to ensure that the gain of the reflector reaches the optimal state. Ordinary narrowband reflector feeds can easily achieve this goal, but for ultra-wideband reflector feeds, it is very difficult to maintain a stable illumination level, which directly affects the performance and reliability of ultra-wideband antennas in practical applications.

[0004] Existing ultra-wideband feed horn antennas have the following disadvantages: 1. The beam width of the traditional ultra-wideband feed horn antenna varies greatly within the frequency range, which makes its performance unstable at different frequencies and makes it difficult to meet the requirements of the reflector feed.

[0005] 2. Unstable illumination level: For reflector antennas, the feed source needs to have a stable illumination level to ensure that the gain of the reflector is optimal. For traditional horn antennas, the difference between low-frequency gain and high-frequency gain is usually 9.5dB in the frequency range of 6GHz to 18GHz, and the low-frequency beam width is generally 3 times the high-frequency beam width. Summary of the invention

[0006] The object of the present invention is to provide an ultra-wideband equal-gain feed horn antenna, which ensures stable illumination level and gain within the ultra-wideband range by changing its structure.

[0007] The present invention adopts the following technical scheme: an ultra-wideband equal-gain feed horn antenna, the frequency range of the horn antenna is 6GHz to 18GHz; the horn antenna comprises an integrally connected uniform circular waveguide, a horn-shaped circular waveguide, and four ridge waveguides fixed in a waveguide cavity composed of the uniform circular waveguide and the horn-shaped circular waveguide;

[0008] The cross section of the trumpet-shaped circular waveguide gradually increases, and four ridge waveguides are arranged symmetrically and orthogonally in the waveguide cavity;

[0009] The ridge curves of the four ridge waveguides are: y=ae bx +cx+d; in, ;

[0010] The curve of the waveguide cavity is: y=me Bx +cx+n; in, ;

[0011] Wherein, a is half of the spacing between two adjacent ridge waveguides among the four ridge waveguides; x∈(0,h); h is the length of the ridge; c, d, m, n, and p are all constants; D is the diameter of the horn of the horn-shaped circular waveguide; and j is the distance between the end of the ridge curve and the waveguide cavity.

[0012] Furthermore, D is 1.8λ; j is 0.5λ; h is 1.8λ, a is 0.019λ; λ is the wavelength of the center frequency of the horn antenna; the gain variation range of the horn antenna is 9dB to 12dB; the electric field beam width variation range is 68° to 39°; the magnetic field beam width variation range is 68° to 40°.

[0013] Furthermore, the thickness of the four ridge waveguides is 1.5-2.1 mm.

[0014] The beneficial effects of the present invention are: The present invention adopts an exponentially gradual ridge waveguide and an exponentially gradual waveguide cavity to obtain an almost constant gain and a stable beam width; The present invention has two feeding ports, one is a vertical polarization feeding port, and the other is a horizontal polarization feeding port. The two feeding ports are orthogonally arranged and staggered with each other, so that better port isolation and polarization isolation can be obtained, and the orthogonal polarization multiplexing of the antenna can be satisfied. When the present invention is used alone as a horn antenna, it can provide reliable signal coverage and radiation characteristics at different frequencies. Due to the stable gain characteristics of the present invention, signal strength fluctuations caused by frequency changes are avoided, thereby reducing problems such as dropped calls and data transmission errors in communications. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of the horn antenna according to Embodiment 1 of the present invention; Figure 2 is a cross-sectional view of the horn antenna of Example 1 of the present invention; Figure 3 is a standing wave curve of the horn antenna of Example 1 of the present invention; Figure 4 is a gain variation curve of the horn antenna of Example 1 of the present invention; Figure 5 This is a beam width variation curve of the horn antenna in Example 1 of the present invention.

[0016] Among them: 10. Uniform circular waveguide; 11. Trumpet-shaped circular waveguide; 12. Ridge waveguide. DETAILED DESCRIPTION

[0017] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] 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.

[0019] The invention discloses an ultra-wideband equal-gain feed horn antenna, such as Figure 1 As shown, the frequency range of the horn antenna is 6 GHz to 18 GHz. The horn antenna includes an integrally connected uniform circular waveguide 10 , a horn-shaped circular waveguide 11 , and four ridge waveguides 12 fixed in a waveguide cavity formed by the uniform circular waveguide 10 and the horn-shaped circular waveguide 11 .

[0020] The cross section of the horn-shaped circular waveguide 11 gradually increases, and four ridge waveguides 12 are symmetrically arranged in pairs and orthogonally to each other in the waveguide cavity.

[0021] The ridge curves of the four ridge waveguides 12 are: y=ae bx +cx+d; in, .

[0022] The curve of the waveguide cavity is: y=me Bx +cx+n; in, .

[0023] Wherein, a is half of the spacing between two adjacent ridge waveguides 12 among the four ridge waveguides 12; x∈(0,h); h is the length of the ridge; c, d, m, n, and p are all constants; D is the diameter of the horn mouth of the horn-shaped circular waveguide 11; and j is the distance between the end of the ridge curve and the waveguide cavity.

[0024] Example 1: Take λ=300 / f, λ is the wavelength of the center frequency of the horn antenna, f=(6+18) / 2=12GHz, then λ=25mm, then a=0.019λ=0.48mm, D =1.8λ=45mm, j=0.5λ=12.6mm, h =1.8λ=45mm, the thickness of the ridge waveguide 12 is 1.8mm, c=0.02, d=0, m=0.2, n=10.5, p=0.3, and then get Figure 2 The horn antenna shown.

[0025] The standing wave curve of the horn antenna obtained in this embodiment is as follows: Figure 3 As shown in FIG. 1 , the standing wave in the full frequency band is within 1.8, which fully meets various application scenarios. The gain variation curve of the horn antenna obtained in this embodiment is shown in FIG. Figure 4 As shown in FIG. 1 , within the ultra-wide frequency band of 6 GHz to 18 GHz, the gain variation range is 9 dB to 12 dB, and the gain curve approaches a straight line. The beam width variation curve of the horn antenna obtained in this embodiment is shown in FIG. Figure 5 As shown, within the ultra-wide frequency band of 6 GHz to 18 GHz, the electric field beam width varies from 68° to 39°, and the magnetic field beam width varies from 68° to 40°.

[0026] In the range of 6 GHz to 18 GHz, the antenna of this embodiment shows excellent performance, and its gain change curve shows a relatively gentle trend, and the gain change range is strictly controlled within ±1.5 dB. This means that in the range of 6 GHz to 18 GHz, the gain fluctuation of the antenna is extremely small, and it can provide highly stable gain support for signal transmission and reception. In contrast, the gain of a traditional horn antenna tends to increase linearly with increasing frequency.

[0027] At the same time, the beam width change curve of the antenna of this embodiment also has significant characteristics. The beam width range is ±14.5°, which shows that the change of beam width is relatively stable in the range of 6GHz to 18GHz. The stability of beam width is crucial to the performance of the antenna, especially in some application scenarios with strict requirements on beam directivity and coverage. For wireless communications, a stable beam width helps to achieve more uniform signal coverage and reduce signal blind spots and coverage overlap problems caused by changes in beam width.

[0028] 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. An ultra-wideband equal-gain feed horn antenna, characterized in that: The frequency range of the horn antenna is 6 GHz to 18 GHz; the horn antenna comprises an integrally connected uniform circular waveguide (10), a horn-shaped circular waveguide (11), and four ridge waveguides (12) fixed in a waveguide cavity formed by the uniform circular waveguide (10) and the horn-shaped circular waveguide (11); The cross-section of the horn-shaped circular waveguide (11) gradually increases, and the four ridge waveguides (12) are arranged symmetrically in pairs and orthogonally to each other in the waveguide cavity; The ridge curves of the four ridge waveguides (12) are: y=ae bx +cx+d; in, ; The curve of the waveguide cavity is: y=me Bx +cx+n; in, ; Wherein, a is half of the distance between two adjacent ridge waveguides (12) among the four ridge waveguides (12); x∈(0,h); h is the length of the ridge; c, d, m, n, p are all constants; D is the diameter of the horn of the horn-shaped circular waveguide (11); and j is the distance between the end of the ridge curve and the waveguide cavity.

2. The ultra-wideband equal-gain feed horn antenna according to claim 1, characterized in that: The D is 1.8λ; the j is 0.5λ; the h is 1.8λ, and the a is 0.019λ; wherein λ is the wavelength of the center frequency of the horn antenna; the gain variation range of the horn antenna is 9dB to 12dB; the electric field beam width variation range is 68° to 39°; and the magnetic field beam width variation range is 68° to 40°.

3. The ultra-wideband equal-gain feed horn antenna according to claim 1, characterized in that: The thickness of the four ridge waveguides (12) is 1.5-2.1 mm.

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