CN-122026080-A - Wave-absorbing ultra-surface low-profile wide-angle RCS (radio frequency section) reduced tight coupling dipole antenna

CN122026080ACN 122026080 ACN122026080 ACN 122026080ACN-122026080-A

Abstract

The invention discloses a wave-absorbing ultra-surface low-profile wide-angle RCS reduced tightly-coupled dipole antenna. The array is composed of a radiation layer, an intermediate layer, a wave-absorbing super-surface layer and a metal stratum. The top layer of the radiation layer is a dipole antenna, the tail ends of the radiation arms are loaded with coupling patches through metal through holes, the middle layer is a dielectric substrate, the top layer of the wave-absorbing super-surface layer is a pair of symmetrical three-fork-shaped resistive films loaded with the metal through holes, the bottom layer is the dielectric substrate, and the metal stratum is positioned at the lowest layer. The wave-absorbing super-surface is embedded in the tightly coupled dipole array antenna, and replaces the traditional metal ground, so that a low-profile structure is realized. The antenna has wave absorption efficiency higher than seventy-five percent when electromagnetic waves are incident at a wide angle of zero to sixty degrees in a seven-fourteen gigahertz frequency band, good radiation performance and wide angle scanning capability are maintained, and radar scattering cross section is obviously reduced. The invention can be popularized to the design of the low radar cross section of the traditional antenna, and is suitable for radar and wireless communication systems.

Inventors

CHENG QIANG
Gao Gege
LI HUIDONG
DAI JUNYAN

Assignees

东南大学

Dates

Publication Date: 20260512
Application Date: 20260415

Claims (7)

1. The wave-absorbing ultra-surface low-profile wide-angle RCS reduced tightly-coupled dipole antenna is characterized by comprising a metal stratum (6), a wave-absorbing ultra-surface layer (4), an intermediate layer (3) and a radiation layer (1) from bottom to top in sequence; Wherein, the The radiating layer (1) comprises a dipole antenna (1-1) on the top layer and an upper dielectric substrate (2) positioned below the dipole antenna, and a coupling patch (1-5) is loaded at the tail end of one radiating arm of the dipole antenna (1-1) through a metal through hole (1-4); The intermediate layer (3) is an intermediate medium substrate; the wave-absorbing super-surface layer (4) comprises a top-layer resistance film structure and a lower-layer dielectric substrate (5) positioned below the top-layer resistance film structure, wherein the resistance film structure is a pair of symmetrical three-fork-shaped resistance film structures (4-1), and a metal through hole (4-2) is loaded in the center of each resistance film structure (4-1); The metal stratum (6) is positioned on the lower surface of the lower dielectric substrate (5); The wave-absorbing super-surface layer (4) is loaded between the dipole antenna (1-1) and the metal stratum (6) and is used for absorbing incident electromagnetic waves to reduce radar scattering cross section and keep the antenna low in cross section.
2. The wave-absorbing ultra-surface low-profile wide-angle RCS reduced close-coupled dipole antenna according to claim 1, characterized in that the dipole antenna (1-1) has two radiating arms, wherein the first radiating arm has its start connected to a metal probe (1-2) for feeding and the second radiating arm is connected to the metal ground layer (6) through a grounded metal via (1-3).
3. The wave-absorbing ultra-surface low-profile wide-angle RCS reduced tightly coupled dipole antenna according to claim 1, characterized in that said coupling patch (1-5) is connected to the end of one radiating arm of said dipole antenna (1-1) through said metal via (1-4) for enhancing the tightly coupling effect between antenna elements.
4. The wave-absorbing ultra-surface low-profile wide-angle RCS reduced close-coupled dipole antenna according to claim 1, characterized in that in said symmetrical trident shaped resistive film structure (4-1), each trident branch is terminated with an open structure, said metal vias (4-2) are located at the center intersection of the trident and vertically penetrate said underlying dielectric substrate (5) to connect to said metal ground layer (6).
5. The wave-absorbing ultra-surface low-profile wide-angle RCS reduced close-coupled dipole antenna of claim 1, wherein the antenna is formed by a plurality of antenna elements periodically arranged along an E-plane and an H-plane to form an array, and wherein in the E-direction, the antenna elements of the first and last rows are arranged as sub-elements, said sub-elements not participating in radiation, for reducing array edge truncation effects.
6. The wave-absorbing ultra-surface low-profile wide-angle RCS reduced tightly coupled dipole antenna according to claim 1, wherein the upper dielectric substrate (2), the middle dielectric substrate (3) and the lower dielectric substrate (5) are all F4B dielectric substrates, the thickness of the upper dielectric substrate (2) is 0.5mm, the thickness of the middle dielectric substrate (3) is 1.4mm, and the thickness of the lower dielectric substrate (5) is 3.3mm.
7. The wave-absorbing ultra-surface low-profile wide-angle RCS reduced tightly coupled dipole antenna according to claim 1, wherein the working frequency band of the antenna is 7-14GHz, the wave-absorbing efficiency is not lower than 75% when electromagnetic waves are incident at a wide angle of 0-60 degrees, the main polarization gain loss is less than 1.5dB, the E-plane scanning range reaches +/-50 degrees, the H-plane scanning range reaches +/-55 degrees, and the maximum reduction of the radar scattering cross section is 36.5dB when the electromagnetic waves are perpendicularly incident.

Description

Wave-absorbing ultra-surface low-profile wide-angle RCS (radio frequency section) reduced tight coupling dipole antenna Technical Field The invention relates to the technical field of antennas, in particular to a wave-absorbing ultra-surface low-profile wide-angle RCS (Radar Cross Section ) reduced tightly coupled dipole antenna. Background Stealth technology plays a very important role in modern electronic warfare, radar cross section reduction technology can reduce radar characteristics of military targets, and forces enemy electronic detection systems and weapon platforms to reduce combat effectiveness, so that the sudden prevention capability and survivability of military forces of our party are improved. Array antennas generally have a large radiation aperture surface and therefore a large scattering cross section, which is easily detected by a radar. Therefore, reducing the radar cross section of the array antenna is important to improve the stealth performance of the whole communication system. Tightly coupled dipole array antennas have the radiation performance advantages of low profile and wide bandwidth angular scanning and have become ideal candidates for new generation phased array systems. However, the excellent radiation characteristics are accompanied by significant electromagnetic scattering, which greatly limits the application of the electromagnetic scattering on the stealth platform. The prior art for reducing the RCS of the array antenna mainly comprises loading wave absorbing material, frequency Selective Surface (FSS), artificial Magnetic Conductor (AMC), etc Therefore, while researching the radiation performance, the exploration of an effective wide-angle radar scattering cross section reduction technology is very important to widen the application value and realize the integrated trade-off of radiation and scattering performance. How to achieve RCS reduction in the wide-angle range on the premise of maintaining the low profile and broadband radiation performance of the tightly coupled dipole array antenna is a technical problem to be solved in the art. Disclosure of Invention Technical problems: The invention aims to design an array antenna with low profile and wide bandwidth angle scanning, and meanwhile, the array antenna has the advantages of wide-angle radar scattering cross section reduction performance, low cost and light weight. The technical scheme is as follows: The invention provides a wave-absorbing ultra-surface low-profile wide-angle RCS (radio frequency section) reduced tightly coupled dipole antenna which is integrally divided into a radiation layer, an intermediate layer, a wave-absorbing ultra-surface layer and a metal stratum, wherein the top layer of the radiation layer is a dipole antenna, the tail end of a radiation arm of the dipole antenna is provided with a coupling patch through a metal through hole, a dielectric substrate is sequentially arranged below the dipole antenna, the intermediate layer is arranged as the dielectric substrate, the top layer of the wave-absorbing ultra-surface is a pair of symmetrical three-fork-shaped resistor film structures, the middle of each resistor film structure is provided with a metal through hole, the lower part of each resistor film structure is provided with the dielectric substrate, and the metal stratum is positioned at the bottom layer. The tightly coupled dipole array antenna consists of a dipole antenna, a coupling patch, a metal probe and a metal through hole. The coupling patch is connected with the tail end of the radiating arm of the dipole antenna through a metal through hole, the metal probe is connected with the initial end of the radiating arm of the dipole antenna to feed the dipole antenna, and the metal through hole is connected with the other arm of the dipole antenna and metal ground. The wave-absorbing super-surface structure consists of symmetrical three-fork-shaped resistor films, and a metal through hole is loaded in the middle of each resistor film structure. Further, in the symmetrical trident-shaped resistive film structure, the tail end of each trident branch is of an open structure, and the metal through hole is positioned at the central junction of the trident and vertically penetrates through the medium substrate to be connected to the metal ground. The array antenna is formed by a plurality of units which are arranged periodically along an E face and an H face, and the first row and the last row in the E direction are arranged as sub-elements and do not participate in radiation so as to reduce the edge cutting effect. The medium substrates are made of F4B materials, and the thicknesses of the medium substrates are respectively 0.5mm, 1.4mm and 3.3mm. In the 7-14GHz frequency band, the wave absorption efficiency is not lower than 75% when the wide angle is 0-60 degrees incident, the main polarization gain loss is smaller than 1.5dB, the maximum of the vertical incidence RCS is reduced by 36.5d