CN109994828B

CN109994828B - Broadband slot coupling antenna

Info

Publication number: CN109994828B
Application number: CN201910169860.0A
Authority: CN
Inventors: 刘玉珍; 刘金海; 牛红伟
Original assignee: Shanghai Institute of Microwave Technology CETC 50 Research Institute
Current assignee: Shanghai Institute of Microwave Technology CETC 50 Research Institute
Priority date: 2019-03-06
Filing date: 2019-03-06
Publication date: 2021-06-22
Anticipated expiration: 2039-03-06
Also published as: CN109994828A

Abstract

The invention discloses a broadband slot coupling antenna, which comprises a dielectric baseplate, a dielectric feed support, a differential feed branch line, a radiator, a feed branch section, a grounding bonding pad, a short-circuit column and a feed coupling slot, wherein the dielectric baseplate is provided with a feed slot; the lower surface of the medium bottom plate is a metal ground, a feed coupling gap is carved on the metal surface, and a differential feed branch line and a feed branch section are printed on the upper surface; the feed branch is positioned on the upper surface of the medium bottom plate, and the feed of the differential feed branch is completed in a gap coupling mode; the feed support is positioned between the medium baseplate and the radiating body, is connected with the metal radiating body and feeds the metal radiating body; the grounding pad is positioned on the upper surface of the dielectric base plate and is in short circuit connection with the metal ground on the lower surface of the dielectric base plate through the metal short circuit column; the feed coupling slot realizes the differential feed of the antenna and improves the working bandwidth of the antenna. The invention has simple structure, easy processing and small volume, can realize a wireless communication system of a wide frequency band, and reduces the complexity of the antenna of the communication system.

Description

Broadband slot coupling antenna

Technical Field

The invention belongs to the field of wireless communication, and particularly relates to a broadband slot coupling antenna which can be applied to the design of wireless communication antennas.

Background

With the development of mobile wireless communication systems, the performance requirements of the systems are higher and higher, and antennas are also receiving more and more attention as important components in wireless communication systems. At present, the antenna is developing towards the direction of broadband, miniaturization and low power consumption, and how to design an antenna with high performance and low cost has become a development target of an antenna designer. In recent years, due to the advantages peculiar to the linearly polarized antenna itself, which have the advantages of high system sensitivity and low cross polarization, the antenna has gained wide favor from antenna designers and consumers. In addition, the slot-coupled broadband antenna has a wide operating bandwidth, can meet the requirement of simultaneous operation of signals with multiple channels or different frequencies, and can save the number of antennas in wireless communication equipment, so that the broadband antenna becomes a preferred antenna in wireless communication design.

The antenna is used as a front-end component of a communication system, and is integrated with the system as much as possible on the premise of ensuring the performance of the antenna, which also presents challenges for an antenna designer, and miniaturization and broadband become the development trend of the current antenna. Especially in military communication, in order to avoid interference of enemy, the continuity of communication is ensured, communication technical means such as frequency hopping, spread spectrum and the like are adopted, along with the increasing frequency hopping rate and the increasing frequency hopping range, the original narrow-band antenna can not meet the current communication requirement any more, and therefore, the requirement on the wide-band antenna is increasingly urgent; in addition, as more and more carrier-borne and airborne communication devices are used, the broadband antenna is also receiving more and more attention in order to reduce mutual coupling between different frequency bands and different antennas. Furthermore, in the design of modern airborne wireless communication devices, a conformal antenna or a low-profile antenna needs to be designed to meet the aerodynamic requirements on the premise of ensuring the communication quality. Therefore, how to reduce the size and profile of the antenna while ensuring the performance of the antenna is an important and urgent task at present. As described above, the broadband, miniaturization, and low profile of the antenna have been important research subjects in the antenna field.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, the present invention provides a broadband low-profile antenna, which reasonably utilizes the slot coupling technology to expand the working frequency band of the antenna array, and simultaneously improves the impedance matching characteristics in the working frequency band, and reduces the antenna profile, thereby realizing the low profile and miniaturization of the antenna.

The invention is realized according to the following technical scheme:

a wideband slot-coupled antenna, comprising: the device comprises a dielectric baseplate, a dielectric feed support, differential feed branch lines, a radiator, feed branches, a grounding bonding pad, a short-circuit column and a feed coupling gap; the lower surface of the medium bottom plate is a metal ground, a feed coupling gap is carved on the metal surface, and a differential feed branch line and a feed branch section are printed on the upper surface; the feeding branch is positioned on the upper surface of the medium bottom plate, and the feeding of the differential feeding branch is completed in a gap coupling mode; the feed support is positioned between the dielectric baseplate and the radiating body, is connected with the metal radiating body and feeds the metal radiating body; the grounding pad is positioned on the upper surface of the dielectric base plate and is in short circuit connection with the metal ground on the lower surface of the dielectric base plate through a metal short circuit column; the differential feed of the antenna is realized through the feed coupling slot, the working bandwidth of the antenna is improved, and the maximum radiation direction of the antenna gain is perpendicular to the direction of the metal radiator.

In the above technical scheme, the dielectric bottom plate is made of a polytetrafluoroethylene plate with a dielectric constant of 2.2.

In the above technical solution, the height H of the broadband slot coupled antenna is within a range of 0.14 λ_c～0.15λ_cWherein λ is_cIs the center frequency of the operating band.

In the above technical solution, the dielectric base plate has a rectangular structure.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention utilizes the bracket type feed structure, which can not only support the radiator, but also directly feed the radiator through the bracket.

2. The invention improves cross polarization and makes the radiation pattern of the antenna not deviate from the normal direction of the antenna.

3. The invention improves impedance matching, widens the working bandwidth of the antenna and reduces the profile of the antenna by utilizing the slot coupling technology. Therefore, a miniaturized low-profile antenna is obtained.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a three-dimensional view of an antenna unit of the present invention;

FIG. 2 is a port return loss of the antenna unit of the present invention;

FIG. 3 is an H-plane pattern of the antenna unit of the present invention at 2.2 GHz;

FIG. 4 is an E-plane pattern of the antenna element of the present invention at 2.2 GHz;

in the figure: 102 metal ground; 201. 203, 204, 205 feed the bracket unit; 202 a differential feed leg; 302 an antenna radiating element; 401 feeding branch; 402 a metal pad; 403 short-circuiting pillars; 501 coupling the gaps; wherein 101 and 301 are dielectric substrates.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

The invention relates to a broadband slot coupling antenna, comprising: the device comprises a dielectric baseplate, a dielectric feed support, differential feed branch lines, a radiator, feed branches, a grounding bonding pad, a short-circuit column and a feed coupling gap; the lower surface of the medium bottom plate is a metal ground, a feed coupling gap is carved on the metal surface, and a differential feed branch line and a feed branch section are printed on the upper surface; the feed branch is positioned on the upper surface of the medium bottom plate, and the feed of the differential feed branch is completed in a gap coupling mode; the feed support is positioned between the medium baseplate and the radiating body, is connected with the metal radiating body and feeds the metal radiating body; the grounding pad is positioned on the upper surface of the dielectric base plate and is in short circuit connection with the metal ground on the lower surface of the dielectric base plate through a metal short circuit column; the differential feed of the antenna is realized through the feed coupling slot, the working bandwidth of the antenna is improved, and the maximum radiation direction of the antenna gain is perpendicular to the direction of the metal radiator.

Specifically, referring to fig. 1, an antenna element is formed, wherein a radiating element size S1 is 0.43 λ, an antenna cross-sectional height H is 0.15 λ, and a metal ground 302 of the radiating element is printed on a lower surface of a dielectric substrate 301; the signal is coupled to the differential feed branch 202 by the feed stub 401 via the coupling slot 501 and feeds the metal radiator 302 through the

feed supports

203, 204 connected to the feed branch. The upper surface of the dielectric substrate 101 is printed with a feed branch 401, the lower surface is a metal ground 102, a coupling slot 501 is etched on the metal ground, and a signal is coupled to a differential feed branch line by a slot coupling mode, so that a differential feed signal is formed. The tail end of the feeder 401 is welded with the inner core of the coaxial cable, and the outer skin of the coaxial cable is welded with the welding disc 402; the rectangular dielectric plate is made of polytetrafluoroethylene plates with the dielectric constant of 2.2, and the thickness of the polytetrafluoroethylene plates is 1.2 mm. The effect of the invention can be further explained by combining the simulation result:

1. emulated content

1.1 simulation calculation of the port return loss of the antenna radiation unit used in the above embodiment was performed using commercial simulation software HFSS _15.0, and the result is shown in fig. 2.

1.2 the far-field radiation pattern of the antenna radiation unit used in the above embodiment is simulated by commercial simulation software HFSS _15.0, and the result is shown in fig. 3, wherein fig. 3 is the H-plane radiation pattern of the antenna radiation unit used in the example at 2.2 GHz.

1.3 the far-field radiation pattern of the antenna radiation unit used in the above embodiment was simulated by using commercial simulation software HFSS _15.0, and the result is shown in fig. 3, where fig. 3 is the E-plane radiation pattern of the antenna radiation unit used in the example at 2.2 GHz.

2. Simulation result

Referring to FIG. 2, with | S₁₁The i is less than-10 dB, the antenna operating frequency band of the selected antenna unit in the embodiment is 1.62GHz to 2.82GHz, and the common relative bandwidth is 54.5%.

Referring to fig. 3, the far field radiation pattern of the H-plane at 2.2GHz for the antenna selected in the embodiment, the maximum radiation direction as seen from the figure is always parallel to the Z-axis without any deviation, and the cross polarization is at least 25dB lower than the main polarization, indicating that the dual polarized element has a lower cross polarization.

Referring to fig. 4, the E-plane far-field radiation pattern of the dual-polarized element antenna selected in the embodiment at 2.2GHz, the maximum radiation direction as seen from the figure is always parallel to the Z-axis without any deviation, and the cross polarization is at least 25dB lower than the main polarization, indicating that the dual-polarized element has a lower cross polarization.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.

Claims

1. A wideband slot-coupled antenna, comprising: the feed device comprises a dielectric baseplate, a dielectric feed support, differential feed branch lines, a metal radiator, feed branches, a grounding bonding pad, a short-circuit column and feed coupling gaps; the lower surface of the medium bottom plate is a metal ground, a feed coupling gap is carved on the metal surface, and a differential feed branch line and a feed branch section are printed on the upper surface; the feeding branch is positioned on the upper surface of the medium bottom plate, and the feeding of the differential feeding branch is completed in a gap coupling mode; the feed support is positioned between the dielectric baseplate and the metal radiating body, is connected with the metal radiating body and feeds the metal radiating body; the grounding pad is positioned on the upper surface of the dielectric base plate and is in short circuit connection with the metal ground on the lower surface of the dielectric base plate through a metal short circuit column; the differential feed of the antenna is realized through the feed coupling slot, and the working bandwidth of the antenna is improved, so that the maximum radiation direction of the antenna gain is perpendicular to the direction of the metal radiator;

the broadband slot coupled antenna is a low-profile antenna; the broadband slot coupled antenna height H, theH is in the range of 0.14 lambda_c～0.15λ_cWherein λ is_cIs the center frequency of the working frequency band;

the thickness of the rectangular medium bottom plate is 1.2 mm;

the antenna selects far-field radiation directions of an H surface and an E surface at 2.2GHz, the maximum radiation direction is always parallel to a Z axis, no deviation exists, and the cross polarization is at least 25dB lower than the main polarization.

2. A wideband slot-coupled antenna according to claim 1, wherein the dielectric substrate is made of teflon sheet with a dielectric constant of 2.2.