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CN-122026112-A - Performance optimization method of rectangular horn antenna and rectangular horn antenna

CN122026112ACN 122026112 ACN122026112 ACN 122026112ACN-122026112-A

Abstract

The invention provides a performance optimization method of a rectangular horn antenna and the rectangular horn antenna, the performance optimization method firstly increases a matching section and designs the matching end of the horn antenna into a multi-stage ladder-shaped structure, thereby achieving the effect of reducing the side lobes of an E surface, then, the phase difference between the TM 12 mode and the TM 10 mode is changed by adjusting the length of the third step, the side lobe is further reduced, and the edge line of the inner peripheral wall of the opening angle radiation section is chamfered to inhibit cross polarization. On the premise of keeping the inherent advantages of simple structure, convenient processing, wideband operation and the like to the maximum extent, the invention fundamentally and cooperatively optimizes the radiation characteristics, particularly effectively inhibits the puzzled D plane cross polarization and reduces the side lobe level, thereby meeting the extreme requirements of the next-generation high-performance communication system on the polarization purity of the antenna and the quality of the directional diagram.

Inventors

  • HAN CHONGZHI
  • DING TONGYU
  • XIAO JUN

Assignees

  • 集美大学

Dates

Publication Date
20260512
Application Date
20260209

Claims (10)

  1. 1. The performance optimization method of the rectangular horn antenna is characterized by comprising the following steps of: The horn antenna comprises a feed conversion section and an opening angle radiation section which are sequentially connected, wherein one end of the feed conversion section, which is far away from the opening angle radiation section, is a rectangular waveguide, the other end of the feed conversion section is a feed port, and the radiation port surface of the opening angle radiation section is rectangular; A matching section is designed between the feed conversion section and the opening angle radiation section, and the matching section is designed into a multi-stage ladder structure so as to introduce a TM 12 mode based on a TM 10 mode, wherein the size of one end of the multi-stage ladder structure, which is close to the feed conversion section, is smaller than that of one end, which is close to the opening angle radiation section; Determining an ideal energy duty ratio of a TM 12 mode, determining the number of stages of the multi-stage ladder structure according to the ideal energy duty ratio, realizing an actual energy duty ratio of the TM 12 mode, and simultaneously reducing side lobes of an E surface; The length of the third-stage ladder is regulated, the actual energy duty ratio is changed, so that the actual energy duty ratio is close to the ideal energy duty ratio, and meanwhile, the phase difference between the TM 12 mode and the TM 10 mode can be changed, so that the side lobe of the E surface is further reduced; chamfering is carried out on the edge line of the inner peripheral wall of the opening angle radiation section so as to inhibit cross polarization; the angle and size of the chamfer is adjusted to further suppress cross polarization.
  2. 2. The method of optimizing the performance of a rectangular feedhorn of claim 1, wherein determining the number of steps of the multi-step structure based on the ideal energy ratio, the step of achieving the actual energy ratio of TM 12 mode while lowering the side lobes of the E-plane comprises: The TM 12 mode fills the first null of the far field pattern of the TE 10 mode with the far field pattern of the TM 12 mode at the actual energy duty cycle, merging the first side lobe of the E-plane with the main lobe to reduce the side lobe of the E-plane.
  3. 3. The method of optimizing the performance of a rectangular horn antenna according to claim 2, wherein the ideal energy ratio is 10% to 14%, the number of stages of the multi-stage ladder structure is 3, and the actual energy ratio is 20% to 26%.
  4. 4. The method of optimizing the performance of a rectangular feedhorn according to claim 1 wherein the third step has a length of 8mm to 13.2mm and the phase difference is 16 to 20 degrees.
  5. 5. The method of optimizing the performance of a rectangular horn antenna according to claim 1, wherein in the step of introducing a TM 12 mode based on a TM 10 mode, a first electric field component in the x direction is introduced at the same time, and in the step of chamfering the ridge line of the inner peripheral wall of the opening angle radiating section, a second electric field component in the x direction is introduced, and the directions of the first electric field component and the second electric field component are opposite to each other so as to suppress cross polarization.
  6. 6. The method of optimizing the performance of a rectangular feedhorn of claim 5 wherein the angle and size of the chamfer is adjusted according to the magnitude of the first electric field component.
  7. 7. A rectangular horn antenna, a performance optimization method of which is characterized by comprising a feed conversion section, a matching section and an opening angle radiation section which are sequentially connected, wherein one end of the feed conversion section, which is far away from the matching section, is a rectangular waveguide, the other end of the feed conversion section is a feed port, the matching section is of a multistage ladder structure, the size of the matching section is gradually increased from the feed conversion section to the opening angle radiation section, the multistage ladder structure is used for exciting a higher order mode to reduce a side lobe, the radiation port surface of the opening angle radiation section is rectangular, and a chamfer structure is arranged at the edge line of the inner peripheral wall of the opening angle radiation section and is used for inhibiting cross polarization.
  8. 8. The rectangular feedhorn of claim 7, wherein the rectangular feedhorn has a resonant mode that is a combination of TM 10 mode and TE 12 mode, and the higher order mode is TE 12 mode.
  9. 9. The rectangular feedhorn of claim 7, wherein the number of stages of the multi-stage ladder structure is 3.
  10. 10. The rectangular feedhorn of claim 7, wherein the angle of the chamfer structure is 45 degrees and the chamfer structure has a chamfer length of 2.8mm to 3mm.

Description

Performance optimization method of rectangular horn antenna and rectangular horn antenna Technical Field The invention belongs to the technical field of antennas, and particularly relates to a performance optimization method of a rectangular horn antenna and the rectangular horn antenna. Background In modern wireless communication, satellite links and radar systems in millimeter wave frequency bands, the requirements on antenna performance are extremely high, not only high gain and wide bandwidth are required, but also severe standards are put forward for the purity of the radiation pattern, wherein low cross polarization level and low side lobe level are particularly used as core indexes. Horn antennas are often chosen for their relatively simple structure, good directivity, and large power capacity, but their inherent design limitations are increasingly evident in high-end applications in that conventional rectangular or pyramid horns produce higher cross-polarized radiation in directions offset from the principal plane (particularly the 45-degree oriented D-plane) due to the asymmetry of the E-plane and H-plane field distributions and phase centers. The defect is directly converted into co-channel interference in a dual-polarized or polarized multiplexing system, so that the polarization isolation is seriously deteriorated, the system capacity and the frequency spectrum efficiency are limited, meanwhile, interference signals are undesirably received or radiated due to a high side lobe caused by aperture field mutation and edge diffraction effect, the space selectivity is reduced, and the problem of mutual coupling in a multi-antenna system is possibly aggravated. To address these challenges, prior art solutions tend to suffer from performance and complexity, such as improved performance with multimode, hybrid or corrugated horn configurations, but at the expense of structural simplicity, operating bandwidth and manufacturing costs, the antenna becomes cumbersome and expensive, while suppressing the side lobes by external devices such as external chokes, metal grids, etc., significantly increases the cross-sectional dimensions and may introduce new resonant modes. In addition, some trimming methods based on local shape optimization have limited improvement effect and often have difficulty in achieving cooperative suppression of cross polarization and side lobes, and may even deteriorate impedance matching. Disclosure of Invention The embodiment of the invention aims to provide a performance optimization method of a rectangular horn antenna and the rectangular horn antenna, so as to solve the technical problem that the horn antenna in the prior art is difficult to realize cooperative suppression of cross polarization and side lobes. In order to achieve the above purpose, the technical scheme adopted by the invention is that the rectangular horn antenna comprises the following steps: The horn antenna comprises a feed conversion section and an opening angle radiation section which are sequentially connected, wherein one end of the feed conversion section, which is far away from the opening angle radiation section, is a rectangular waveguide, the other end of the feed conversion section is a feed port, and the radiation port surface of the opening angle radiation section is rectangular; A matching section is designed between the feed conversion section and the opening angle radiation section, and the matching section is designed into a multi-stage ladder structure so as to introduce a TM 12 mode based on a TM 10 mode, wherein the size of one end of the multi-stage ladder structure, which is close to the feed conversion section, is smaller than that of one end, which is close to the opening angle radiation section; Determining an ideal energy duty ratio of a TM 12 mode, determining the number of stages of the multi-stage ladder structure according to the ideal energy duty ratio, realizing an actual energy duty ratio of the TM 12 mode, and simultaneously reducing side lobes of an E surface; The length of the third-stage ladder is regulated, the actual energy duty ratio is changed, so that the actual energy duty ratio is close to the ideal energy duty ratio, and meanwhile, the phase difference between the TM 12 mode and the TM 10 mode can be changed, so that the side lobe of the E surface is further reduced; chamfering is carried out on the edge line of the inner peripheral wall of the opening angle radiation section so as to inhibit cross polarization; the angle and size of the chamfer is adjusted to further suppress cross polarization. Optionally, determining the number of stages of the multi-stage ladder structure according to the ideal energy ratio, and implementing the actual energy ratio of the TM 12 mode while reducing the side lobe of the E-plane includes: The TM 12 mode fills the first null of the far field pattern of the TE 10 mode with the far field pattern of the TM 12 mode at the actual energy duty