CN-122000673-A - Miniaturized microstrip antenna of wireless communication

Abstract

The invention discloses a miniaturized microstrip antenna with a loading periodic umbrella-shaped slot structure, and relates to the technical field of wireless communication. The miniaturized microstrip antenna comprises a dielectric substrate, a metal radiation patch covered on the upper surface of the dielectric substrate and a metal grounding plate covered on the lower surface of the dielectric substrate. The metal radiation patch is etched with a plurality of umbrella-shaped groove structures which are periodically staggered, the single umbrella-shaped groove structure is composed of a section of straight line groove and two sections of circular arc grooves, and the starting points of the circular arc grooves are connected with the tail points of the straight line grooves and extend to two sides respectively. The periodic umbrella-shaped groove structure can obviously reduce the resonant frequency of the antenna on the premise of not increasing the physical size of the antenna, thereby realizing the miniaturization of the electric size of the antenna. The miniaturized microstrip antenna also has higher gain and radiation efficiency, and simultaneously has lower cross polarization level, and is suitable for modern portable wireless communication equipment.

Inventors

• XU XIAOFEI
• CHEN JINHONG
• CHEN WENQI

Assignees

• 上海大学

Dates

Publication Date

20260508

Application Date

20260212

Claims (4)

1. 1. A miniaturized microstrip antenna for wireless communication is characterized by comprising a dielectric substrate 2, a metal radiation patch 1 covered on the upper surface of the dielectric substrate 2, a metal grounding plate 3 covered on the lower surface of the dielectric substrate 2, a plurality of umbrella-shaped groove 5 structures etched on the metal radiation patch 1, wherein the umbrella-shaped groove 5 structures are periodically staggered on the metal radiation patch 1, the single umbrella-shaped groove 5 is formed by a section of straight line groove 501 and two sections of circular arc grooves 502, one end of the straight line groove 501 is a closed end, the other end is a forked end, the two sections of circular arc grooves 502 extend outwards from the forked end of the straight line groove 501 and are bent, and the antenna is fed by a coaxial line 4; The geometric parameters of the umbrella-shaped groove 5 need to satisfy the following 6 space constraint relations so as to ensure that the surface current path of the metal radiation patch 1 is effectively extended and simultaneously ensure good impedance matching characteristics: The slot width of the straight slot 501 is equal to the slot width of the circular slot 502 and the slot width of the umbrella-shaped slot 5, and the slot widths are s; The sum of the length l2 of the straight line groove 501 in the umbrella-shaped groove 5 and the outer diameter r1 of the circular arc groove 502 is required to be smaller than the width W of the metal radiation patch 1, namely, the following geometric constraint relation is satisfied, namely, l2+r1 < W; The inner diameter r0 of the circular arc groove 502, the groove width s of the umbrella-shaped groove 5 and the period P of the umbrella-shaped groove 5 need to satisfy the following geometric constraint relation of 4r0+3s < P; The distance l1 from the linear groove 501 to the edge of the periodic structure, the groove width s of the linear groove 501 and the period P of the umbrella-shaped groove need to satisfy the following geometric constraint relationship of 2l1+s=p; The inner diameter r0, the groove width s and the outer diameter r1 of the circular arc groove 502 need to satisfy the following geometric constraint relation; The arc θ of the arc slot 502 ranges from 0 to pi.
2. 2. A miniaturized microstrip antenna for wireless communication according to claim 1, wherein: the side length G=40mm of the dielectric substrate 2, the relative dielectric constant is 2.2, and the thickness h is 4mm; The length of the metal radiation patch 1 is L=15 mm, and the width is W=15 mm; the side length g=40 mm of the metal grounding plate 3; The metal radiation patch 1 and the metal grounding plate 3 are made of silver, copper or aluminum, the conductivity is better than 10 7 S/m, and the thickness t is 0.035mm; Three umbrella-shaped grooves 5 are loaded on the metal radiation patch 1, the period P of each umbrella-shaped groove 5 is=5mm, and the groove width of each umbrella-shaped groove 5 is s=0.2 mm; the length l2=7.5 mm of the linear groove 501 in the umbrella-shaped groove 5, the distance l1=2.4 mm from the linear groove 501 to the edge of the periodic structure, and the groove width of the linear groove 501 is equal to the groove width of the umbrella-shaped groove 5, and is s=0.2 mm; The inner diameter r0=0.8 mm, the outer diameter r1=1 mm, and the radian θ=3pi/4 of the circular arc groove 502 in the umbrella-shaped groove 5, and the groove width of the circular arc groove 502 is equal to the groove width of the umbrella-shaped groove 5, and s=0.2 mm.
3. 3. The miniaturized microstrip antenna of claim 1, wherein the antenna resonant frequency is 3.594GHz by loading a plurality of umbrella-shaped slots 5 which are periodically staggered, and the resonant frequency is about 6.087GHz for a conventional complete rectangular patch antenna with the same size, and compared with the conventional antenna, the antenna resonant frequency is reduced by more than 40%, and the antenna electrical size is reduced by more than 40%.
4. 4. The miniaturized microstrip antenna of claim 1, wherein the umbrella-shaped slot structure optimally controls the current distribution on the antenna surface in a staggered manner. While realizing miniaturization, the peak gain of the antenna reaches 5.89dBi, the radiation efficiency is as high as 81.6%, and the cross polarization is lower than-16 dB.

Description

Miniaturized microstrip antenna of wireless communication Technical Field The invention belongs to the technical field of wireless communication and microstrip antennas, and particularly relates to a miniaturized microstrip antenna. The invention realizes miniaturization of antenna electric size by loading special-shaped slotting structure, and simultaneously maintains high gain and high efficiency characteristics. Background Microstrip antennas are widely used in wireless communication systems because of their low profile, light weight, ease of processing and integration, etc. However, the resonant frequency of a conventional microstrip antenna is closely related to its physical size, and the patch size is typically about half the operating wavelength. When operation at lower frequencies (e.g., S-band) is required, antenna sizes tend to be large, and it is difficult to meet the stringent requirements of modern portable and integrated communication devices for device miniaturization. In order to achieve miniaturization of microstrip antennas, the conventional technology includes the use of high dielectric constant substrates or etching grooves (e.g., rectangular grooves, U-shaped grooves, meander lines, etc.) in the surface of the patch to extend the surface current path. Although the technology realizes the miniaturization of the antenna size, the technology also faces the degradation of other performances, namely the high dielectric constant substrate can obviously reduce the bandwidth of the antenna and increase the surface wave loss, and the traditional simple slotting technology often damages the radiation aperture distribution, so that the radiation efficiency of the antenna is greatly reduced, the gain is seriously reduced, even the negative gain appears, and the actual communication requirement cannot be met. The invention patent with publication number CN 121355602A discloses a microstrip patch antenna based on antipodal double spiral grooves, which adopts a double spiral groove structure, wherein the geometric construction mode is spiral line slotting, and the two spiral grooves are antipodal to each other, but do not show periodic staggered characteristics. The invention patent with publication number CN 121460947A discloses a miniaturized circular patch antenna loaded with symmetrical four L-shaped grooves and wireless communication equipment thereof, which adopts an L-shaped groove structure, wherein the geometric construction mode is L-shaped grooves, the four L-shaped grooves are symmetrically distributed around the circle center, and the periodic staggered characteristic is not presented. Therefore, there is a need to design a novel slotting structure that is different from the existing geometric configuration and that can exhibit periodic staggered features. In particular, after the antenna is loaded with the novel periodic staggered slot structure, the physical size can be obviously reduced, and higher gain and efficiency can be maintained. Disclosure of Invention The invention aims to overcome the defects of the existing wireless communication antenna technology, and the current path is effectively folded on the minimum patch area by introducing a special geometric configuration of an umbrella-shaped groove structure into the metal radiation patch, so that the miniaturization of the antenna electrical size is realized; furthermore, the invention designs the umbrella-shaped grooves into a periodical staggered arrangement mode, effectively overcomes the technical defects of low gain, low efficiency, irregular radiation pattern and the like of the traditional miniaturized antenna, and realizes higher gain and efficiency and good radiation pattern while ensuring the miniaturization of the antenna electric size. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: a miniaturized microstrip antenna for wireless communication comprises a dielectric substrate, a metal grounding plate and a metal radiation patch. And a plurality of umbrella-shaped grooves with the same shape are etched on the metal radiation patch. The antenna is fed by a coaxial line. The umbrella-shaped groove is formed by a straight line groove and two circular arc grooves, the starting point of each circular arc groove is connected with the tail end of each straight line groove and is bent outwards, and the umbrella-shaped groove is similar to an umbrella in overall configuration, so that the umbrella-shaped groove is named as an umbrella-shaped groove. The plurality of umbrella-shaped groove structures are periodically staggered on the metal radiation patch along the length direction. The metal radiation patch is divided into a plurality of units with the same size, each unit is internally provided with an umbrella-shaped groove, the center distance between every two adjacent umbrella-shaped grooves, namely, the unit period is P, and furthermore, umbrella-shaped groove structures