CN-122000668-A - Wide-band medium cap-shaped feed source and antenna

CN122000668ACN 122000668 ACN122000668 ACN 122000668ACN-122000668-A

Abstract

The invention discloses a wide-frequency-band medium cap-shaped feed source and an antenna, wherein the feed source comprises a shaped circular waveguide tube and a medium cap, the shaped circular waveguide tube is connected with the medium cap, the outer wall of the shaped circular waveguide tube is provided with a multi-stage ladder-shaped shaping structure, each stage ladder-shaped shaping structure in the multi-stage ladder-shaped shaping structure is respectively used as a quarter-wavelength impedance converter for realizing the broadband impedance matching of electromagnetic waves, the medium cap is provided with a bending structure for carrying out collimation conversion on the directions of the electromagnetic waves, and each stage ladder sequentially connected along the horizontal direction is used for realizing the phase compensation of the electromagnetic waves, so that the high-performance work of K/Ka wide frequency band can be realized.

Inventors

LIU JIANG
ZHAO WEI
CHEN RONGSHENG
ZENG ZHONGCHENG
CHENG WEI
YUAN YANWU

Assignees

合肥九盛卫星科技有限公司

Dates

Publication Date: 20260508
Application Date: 20251226

Claims (10)

1. The utility model provides a wide frequency band medium cap shape feed, its characterized in that includes shaping circle waveguide and medium cap, shaping circle waveguide is connected with the medium cap, the outer wall of shaping circle waveguide is equipped with multistage echelonment shaping structure, the ladder shaping structure at each stage in the multistage echelonment shaping structure is used for realizing the broadband impedance matching of electromagnetic wave as quarter wavelength impedance transformer respectively, the medium cap is equipped with the kink structure and is used for carrying out collimation transformation to the direction of electromagnetic wave, the kink structure includes that the ladder at each stage that connects gradually along the horizontal direction is used for realizing the phase compensation of electromagnetic wave.
2. The broad frequency band dielectric cap feed of claim 1, wherein radial dimensions and axial dimensions of each stage of the stepped forming structure are set to present a specific characteristic impedance at a corresponding center frequency point, the radial dimensions being a sum of a binomial coefficient of a corresponding characteristic impedance sequence and a radial dimension compensation value, and the axial dimensions being a sum of an integer multiple of a quarter wave length of the corresponding center frequency point and an axial dimension compensation value.
3. The wide-frequency-band medium hat feed source according to claim 2, wherein the multi-stage ladder-shaped shaping structure at least comprises a four-stage ladder shaping structure, a center frequency point corresponding to the first-stage ladder shaping structure is 19GHz, characteristic impedance is 116 Ω, a center frequency point corresponding to the second-stage ladder shaping structure is 22.5GHz, characteristic impedance is 114 Ω, a center frequency point corresponding to the third-stage ladder shaping structure is 26GHz, characteristic impedance is 196 Ω, a center frequency point corresponding to the fourth-stage ladder shaping structure is 29.5GHz, characteristic impedance is 337 Ω, a value range of the radial dimension compensation value is 0.4 mm-1.24 mm, and a value range of the axial dimension compensation value is-3.77 mm-0.6 mm.
4. A broadband medium hat feed according to claim 3, wherein the radial dimension of the first step ladder shaped structure is 16.10mm, the axial dimension is 1.91mm, the radial dimension of the second step ladder shaped structure is 17.34mm, the axial dimension is 5.78mm, the radial dimension of the third step ladder shaped structure is 21.30mm, the axial dimension is 5.05mm, the radial dimension of the fourth step ladder shaped structure is 19.60mm, and the axial dimension is 3.23mm.
5. The broad band dielectric cap feed of claim 1, further comprising a dielectric support assembly, the shaped circular waveguide and the dielectric cap being indirectly connected by the dielectric support assembly, the dielectric support assembly being made of crosslinked polystyrene, a lower portion of the dielectric support assembly being in close abutment with the shaped circular waveguide, an upper portion of the dielectric support assembly being in close abutment with the dielectric cap.
6. The wide-band medium cap feed source according to claim 5, wherein the bending structure further comprises a planar structure and a curved surface structure, the inner diameter of the planar structure is set to be matched with the outer diameter of the upper portion of the medium supporting component so as to enable the upper portion of the medium supporting component to be closely abutted with the medium cap, and the curvature of the curved surface structure is calculated iteratively according to the incident angle of the electromagnetic wave.
7. The broad frequency band dielectric cap feed of claim 1, wherein the dielectric constant of each stage ladder is between air and the dielectric support assembly, the initial value is one quarter of the free space wavelength of the center frequency of the electromagnetic wave, the thickness of each stage ladder is the sum of integer or fractional times of the initial value and the corresponding thickness compensation value, and the length of each stage ladder takes the sum of fractional times of the initial value and the corresponding length compensation value.
8. The wide-band medium cap feed source according to claim 7, wherein each step at least comprises eight steps, the initial value is 3.20mm, the value range of the thickness compensation value is-0.31 mm-2.6 mm, and the value range of the length compensation value is-0.59 mm-0.55 mm.
9. The wide-band medium hat feed of claim 3, wherein the first step has a thickness of 0.19mm, a length of 1.51mm, the second step has a thickness of 1.39mm, a length of 3.05mm, the third step has a thickness of 3.27mm, a length of 2.43mm, the fourth step has a thickness of 0.16mm, a length of 0.41mm, a fifth step has a thickness of 0.84mm, a length of 1.21mm, a sixth step has a thickness of 0.10mm, a length of 0.54mm, a seventh step has a thickness of 0.10mm, a length of 2.00mm, a thickness of the eighth step has a thickness of 2.00mm, and a length of 0.64mm.
10. A wide frequency band antenna comprising a wide frequency band dielectric cap feed as claimed in any one of claims 1 to 9 for transmitting/receiving antenna signals.

Description

Wide-band medium cap-shaped feed source and antenna Technical Field The invention relates to the technical field of antenna communication, in particular to a wide-band medium hat-shaped feed source and an antenna. Background With the rapid development of global satellite communication technology, the demand for communication system capacity has presented a continuously growing situation. The diversified development of the modern satellite communication application scene brings higher requirements to the transmission efficiency and bandwidth performance of an antenna system. The feed source is used as a key component of the parabolic antenna system and plays an important role in converting high-frequency current or bound electromagnetic waves in the waveguide into free space radiation electromagnetic waves. The performance of the antenna directly determines the gain efficiency, radiation pattern and impedance matching characteristics of the antenna, and is a core link of high-gain antenna design. Among the technical schemes of the feeds, the medium cap-shaped feed has become a preferable scheme of the small-caliber parabolic antenna by virtue of the unique structural characteristics, and the main advantages are as follows: In the aspect of structural design, an integrated medium forming technology is adopted, so that the complex assembly structure of the traditional feed source is greatly simplified, and the manufacturing difficulty and the production cost are reduced. The antenna system has the advantages of good radiation characteristics and high caliber efficiency. The compact structural design is particularly suitable for being applied to modern miniaturized communication equipment, and technical support is provided for the miniaturization development of terminal equipment. At present, the feed source of the type is widely applied to a plurality of fields of satellite communication, radar systems and the like, and becomes an important technical path for improving the comprehensive performance of a small-caliber antenna system. Currently, conventional K/Ka frequency band dielectric cap antennas have significant limitations in terms of bandwidth performance. The antenna has the advantages that the typical bandwidth of the receiving frequency band is about 1.8GHz, the bandwidth of the transmitting frequency band is about 1.6GHz, and the application flexibility of the antenna is severely restricted by the narrow-band characteristic. With the rapid development of satellite communication technology, antenna designs are evolving toward a broad frequency. The requirements of the industry on the relative bandwidth of the antenna are increasingly increased, and the requirements of K/Ka satellite communication full-band coverage are met. An ideal broadband antenna needs to keep stable voltage standing wave ratio, radiation gain and other key electrical performance indexes in the whole working frequency band. The existing cap-shaped feed source technology faces multiple challenges when the broadband work is realized, namely the impedance matching difficulty is obviously increased along with the expansion of the broadband, the stability of a phase center in the broadband range is difficult to ensure, and the consistency of radiation patterns faces technical bottlenecks. There is a significant gap between the current state of the art and the industry development demands, and the traditional design thought needs to be broken through, and a novel broadband hat-shaped feed source technical scheme is developed. The technical breakthrough has important significance for promoting the miniaturization and multifunctional development of the satellite communication equipment. Disclosure of Invention In order to solve the problems, the invention provides a wide-frequency dielectric cap-shaped feed source and an antenna. According to one aspect of the invention, a wide-frequency-band medium cap-shaped feed source is provided, the feed source comprises a shaped circular waveguide tube and a medium cap, the shaped circular waveguide tube is connected with the medium cap, a multi-stage ladder-shaped shaping structure is arranged on the outer wall of the shaped circular waveguide tube, each stage ladder-shaped shaping structure in the multi-stage ladder-shaped shaping structure is used as a quarter-wavelength impedance converter for realizing broadband impedance matching of electromagnetic waves respectively, the medium cap is provided with a bending structure for carrying out collimation conversion on the directions of the electromagnetic waves, and each stage ladder sequentially connected along the horizontal direction is used for realizing phase compensation of the electromagnetic waves. Specifically, radial dimensions and axial dimensions of each stage of stepped forming structures in the multi-stage stepped forming structure are set to present specific characteristic impedance at corresponding center frequency points, the radial