CN-122026088-A - Bidirectional wave beam scanning leaky-wave antenna based on trapezoidal sliding symmetrical structure

CN122026088ACN 122026088 ACN122026088 ACN 122026088ACN-122026088-A

Abstract

The invention discloses a bidirectional wave beam scanning leaky-wave antenna based on a trapezoid sliding symmetrical structure, which comprises an input end transition part, an electromagnetic field modulation radiation array and an output end transition part, wherein the input end transition part, the electromagnetic field modulation radiation array and the output end transition part are used for matching absorption, which are sequentially connected, a second rectangular waveguide cavity is arranged in the electromagnetic field modulation radiation array, a cascaded sliding symmetrical trapezoid metal resonant cavity is introduced into the inner sides of the upper wall and the lower wall of the second rectangular waveguide cavity, the sliding symmetrical trapezoid metal resonant cavity has the same geometric dimension and is staggered by half of a structural period in the propagation direction, the upper wall of the electromagnetic field modulation radiation array is provided with a radiation slot array to form a composite energy coupling area used for electromagnetic field modulation, the input end transition part and the output end transition part are of symmetrical structures, and a gradual impedance matching section is arranged in the first rectangular waveguide cavity close to the electromagnetic field modulation radiation array to realize smooth impedance conversion and field type matching, and can simultaneously support transmission of a fast wave mode and a slow wave mode.

Inventors

WANG YUJIE
LIAO XIAOYI
LI YAN
Qian Xiangcheng
JIANG HAOLIN
FANG XIAOXING

Assignees

南京信息工程大学

Dates

Publication Date: 20260512
Application Date: 20260409

Claims (10)

1. The bidirectional wave beam scanning leaky-wave antenna based on the trapezoidal sliding symmetrical structure is characterized by comprising an input end transition part for feeding, an electromagnetic field modulation radiation array and an output end transition part for matching absorption, which are connected in sequence; The electromagnetic field modulation radiation array is internally provided with a second rectangular waveguide cavity, and cascaded sliding symmetrical trapezoid metal resonant cavities are introduced into the inner sides of the upper wall and the lower wall of the second rectangular waveguide cavity, and comprise a first trapezoid metal resonant cavity periodically arranged on the inner side of the upper wall and a second trapezoid metal resonant cavity periodically arranged on the inner side of the lower wall, wherein the geometric dimensions of the first trapezoid metal resonant cavity and the second trapezoid metal resonant cavity are the same and are staggered for half of a structural period in the propagation direction; The input end transition part and the output end transition part are of symmetrical structures, a first rectangular waveguide cavity is arranged in the input end transition part and the output end transition part, a gradual change impedance matching section is arranged in the first rectangular waveguide cavity close to the electromagnetic field modulation radiation array, a plurality of trapezoid gradual change resonant cavities are symmetrically arranged on the inner sides of the upper wall and the lower wall of the first rectangular waveguide cavity in a sliding mode, the sizes of the trapezoid gradual change resonant cavities are in gradient evolution along the propagation direction, and the trapezoid gradual change resonant cavities are communicated with a second rectangular waveguide cavity at the joint of the trapezoid gradual change resonant cavities and the electromagnetic field modulation radiation array, so that smooth impedance conversion and field type matching are realized; The bidirectional wave beam scanning leaky-wave antenna can simultaneously support the transmission of a fast wave mode and a slow wave mode, wherein wave beam scanning of a forward region is realized in a fast wave region, and wave beam scanning of a backward region is realized in a slow wave region by using excited space harmonics.
2. The dual-directional beam scanning leaky-wave antenna based on a ladder slipping symmetrical structure according to claim 1, wherein the radiating slot array comprises a plurality of open three-dimensional radiating elements periodically arranged outside an upper wall of the second rectangular waveguide cavity, the open three-dimensional radiating elements are of symmetrical cross-shaped slot structures communicated with a bottom edge of the first trapezoidal metal resonant cavity, and an upper wall opening at an upper bottom of the first trapezoidal metal resonant cavity is communicated with symmetrical cross-shaped slots of the open three-dimensional radiating elements to form a composite energy coupling area for electromagnetic field modulation.
3. A two-way beam scanning leaky-wave antenna based on a trapezoidal sliding symmetrical structure according to claim 1, wherein in the electromagnetic field modulating radiation array, the unit structure period p=4.5 mm.
4. The bidirectional wave beam scanning leaky-wave antenna based on the trapezoidal sliding symmetrical structure according to claim 3, wherein the first trapezoidal metal resonant cavity and the second trapezoidal metal resonant cavity are both isosceles trapezoid structures, the depth V h of the first trapezoidal metal resonant cavity and the second trapezoidal metal resonant cavity=2.1 mm, the length L c of the upper bottom=1.2 mm, the length L d of the lower bottom=4.0 mm, and the length L k =1.2 mm of an upper wall opening at the upper bottom of the first trapezoidal metal resonant cavity; The distance between adjacent first trapezoid metal resonant cavities in the propagation direction and the distance between adjacent second trapezoid metal resonant cavities in the propagation direction are L b =0.5 mm; The height T h =0.7 mm and the width W a =5.5 mm of the second rectangular waveguide cavity.
5. The dual directional beam scanning leaky-wave antenna based on a ladder slipping symmetrical structure according to claim 2, wherein the cross-shaped slot structure includes a first rectangular cavity, a radiation slot and a second rectangular cavity connected in sequence.
6. The dual directional beam scanning leaky-wave antenna based on a ladder slipping symmetrical structure according to claim 5, wherein a total height of said cross-shaped slot structure is J h = 5mm; The heights C h of the first rectangular cavity and the second rectangular cavity are 2mm, and the lengths of the first rectangular cavity and the second rectangular cavity are L k =1.2 mm; The radiation slit height K h =1 mm, and the radiation slit length is 2.9mm.
7. The leaky-wave antenna for bidirectional beam scanning based on a ladder sliding symmetric structure according to claim 1, wherein a first rectangular waveguide cavity has a height G h =2.3 mm and a width W a =5.5 mm.
8. The bidirectional beam scanning leaky-wave antenna based on trapezoidal sliding symmetrical structure according to claim 1, wherein a unit period of the gradual impedance matching section is 4.5mm.
9. The dual-beam scanning leaky-wave antenna based on a ladder slipping symmetrical structure according to claim 1, wherein the plurality of ladder type graded resonators axially sequentially includes a first ladder type graded resonator, a second ladder type graded resonator and a third ladder type graded resonator.
10. The leaky-wave antenna for bidirectional beam scanning based on a ladder slipping symmetrical structure according to claim 1, wherein a depth V h1 of the first ladder-type graded resonator is 1.2mm, a length L c1 = 0.29mm of an upper bottom, and a length L d1 = 1.89mm of a lower bottom; The depth V h2 of the second trapezoid gradient resonant cavity is 1.5mm, the length L c2 of the upper bottom is=0.36 mm, and the length L d2 of the lower bottom is=2.36 mm; The third ladder-shaped graded resonator has a depth V h3 of 1.8mm, an upper base length L c3 =0.43 mm, and a lower base length L d3 =2.83 mm.

Description

Bidirectional wave beam scanning leaky-wave antenna based on trapezoidal sliding symmetrical structure Technical Field The invention belongs to the technical field of microwave millimeter wave bands, and particularly relates to a bidirectional wave beam scanning leaky-wave antenna based on a trapezoidal sliding symmetrical structure. Background In microwave millimeter wave radar, satellite communication, and high gain wireless communication systems, leaky Wave Antennas (LWAs) are attracting attention as an effective terminal capable of realizing beam scanning. The leaky-wave antenna leads signals to radiate continuously to space in the propagation process by introducing a discontinuous structure on a transmission line, and continuous scanning of beam pointing can be realized by changing the frequency. However, conventional leaky-wave antennas often implement forward beam scanning, and achieving efficient and stable bi-directional scanning remains a challenge. Conventional approaches often require complex dual-port feed networks or specific structural symmetries to excite symmetrical radiation components, which increases system complexity and loss. Therefore, how to realize the leaky-wave antenna with high gain stability and two-way coverage while keeping the compact structure has important practical value and engineering significance. Disclosure of Invention In view of at least one of the technical problems, the invention provides a bidirectional wave beam scanning leaky-wave antenna based on a trapezoidal sliding symmetrical structure, which aims at solving the problem that the conventional leaky-wave antenna is difficult to realize efficient bidirectional wave beam scanning in a single feed state. The technical scheme adopted by the invention is as follows: The invention provides a bidirectional wave beam scanning leaky-wave antenna based on a trapezoidal sliding symmetrical structure, which comprises an input end transition part for feeding, an electromagnetic field modulation radiation array and an output end transition part for matching absorption, which are connected in sequence; The electromagnetic field modulation radiation array is internally provided with a second rectangular waveguide cavity, and cascaded sliding symmetrical trapezoid metal resonant cavities are introduced into the inner sides of the upper wall and the lower wall of the second rectangular waveguide cavity, and comprise a first trapezoid metal resonant cavity periodically arranged on the inner side of the upper wall and a second trapezoid metal resonant cavity periodically arranged on the inner side of the lower wall, wherein the geometric dimensions of the first trapezoid metal resonant cavity and the second trapezoid metal resonant cavity are the same and are staggered for half of a structural period in the propagation direction; The input end transition part and the output end transition part are of symmetrical structures, a first rectangular waveguide cavity is arranged in the input end transition part and the output end transition part, a gradual change impedance matching section is arranged in the first rectangular waveguide cavity close to the electromagnetic field modulation radiation array, a plurality of trapezoid gradual change resonant cavities are symmetrically arranged on the inner sides of the upper wall and the lower wall of the first rectangular waveguide cavity in a sliding mode, the sizes of the trapezoid gradual change resonant cavities are in gradient evolution along the propagation direction, and the trapezoid gradual change resonant cavities are communicated with a second rectangular waveguide cavity at the joint of the trapezoid gradual change resonant cavities and the electromagnetic field modulation radiation array, so that smooth impedance conversion and field type matching are realized; The bidirectional wave beam scanning leaky-wave antenna can simultaneously support the transmission of a fast wave mode and a slow wave mode, wherein wave beam scanning of a forward region is realized in a fast wave region, and wave beam scanning of a backward region is realized in a slow wave region by using excited space harmonics. In some embodiments, the radiating slot array comprises a plurality of open three-dimensional radiating elements periodically arranged outside the upper wall of the second rectangular waveguide cavity, wherein the open three-dimensional radiating elements are of symmetrical cross-shaped groove structures communicated with the bottom edge of the first trapezoid metal resonant cavity; in some embodiments, the electromagnetic field modulates the radiating array with a cell structure period p=4.5 mm. In some embodiments, the first trapezoidal metal resonant cavity and the second trapezoidal metal resonant cavity are both isosceles trapezoid structures, the depths V h of the first trapezoidal metal resonant cavity and the second trapezoidal metal resonant cavity=2.1 mm, the lengths L c =1.2 mm of