CN221427993U - Broadband end-fire array antenna with conformal metal surface - Google Patents

Abstract

The invention relates to a broadband end-fire array antenna with conformal metal surface, belonging to the field of electronic science and technology. The device comprises a microwave PCB, a coplanar bonding pad, a metal pin and a metallized hole; the microwave PCB comprises an upper layer PCB and a lower layer PCB, a plurality of radiation patches are etched on the front surface of the upper layer PCB, microstrip feeder lines are etched on the back surface of the lower layer PCB, and a floor is arranged between the upper layer PCB and the lower layer PCB; the coplanar bonding pad is etched on the back of the lower PCB and is coplanar with the microstrip feeder line; the metal pin is positioned at the center of the radiation patch, penetrates through the upper layer PCB and the lower layer PCB and is connected with the microstrip feeder line; the metallized holes are distributed on the radiation patch and penetrate through the upper PCB to be connected with the floor. The invention uses the circular microstrip patch antenna fed from the bottom center, realizes the sequential hysteresis of smaller radiation patch phases through the bent microstrip feeder, and can realize the antenna design of directional radiation of broadband along the tangential direction of the carrier surface.

Description

A broadband end-fire array antenna conformal to metal surface

Technical Field

The invention belongs to the field of electronic science and technology, and particularly relates to a broadband end-fire array antenna conformal to a metal surface, which forms broadband vertically polarized (perpendicular to the metal surface) directional radiation in the tangent direction along the metal surface.

Background technique

With the development of radio technology, the rate of transmitting information data is required to be faster, the reliability is required to be higher, and the transmission range is wider, which all require antennas to have broadband and directional characteristics. Various electronic devices are installed on a carrier, and the electromagnetic environment of the system becomes more complex. Broadband antennas can replace multiple antennas to avoid electromagnetic interference between systems. In addition, conformal antennas can be designed coplanar with the carrier without affecting its aerodynamic performance. They are widely used in various fields, such as drones, satellites, missiles and other aircraft systems.

In order to improve the confidentiality and anti-interference ability of electromagnetic transmission, antennas usually use directional antennas to transmit or receive electromagnetic waves. Conventional broadband directional antennas mainly include logarithmic periodic antennas, tapered slot antennas and axial mode spiral antennas. For broadband directional antennas, logarithmic periodic antennas and tapered slot antennas, their traditional forms are all composed of vibrators or slots perpendicular to the surface of the carrier. Since the low-frequency cutoff frequency of the vibrator and the slot antenna is related to its longitudinal size, such as the dipole requires a resonant length of 0.5 working wavelengths, and the slot width also needs to reach a width of 0.5 working wavelengths, it is difficult to achieve conformal design. In the prior art, top loading technology is used to reduce the height of the antenna to achieve a low-profile design, but the height and structure of the antenna still have the problem of difficulty in coplanar design. In addition, the prior art also proposes a directional antenna composed of a microstrip patch antenna working in a miniaturized base mode (or static mode), but because it adopts the Yagi antenna working mode, its working bandwidth is greatly limited. In recent years, units equivalent to magnetic flux radiation have been used to solve the problem of directional radiation in the above-mentioned conformal design, but it is still difficult to achieve broadband operation. Therefore, a broadband directional antenna conformal to the surface of a metal carrier has been proposed, which has great practical application value.

Summary of the invention

The technical problems to be solved by the present invention are:

In order to solve the technical defect that the existing coplanar antennas radiating directionally along the metal surface cannot achieve broadband, the present invention provides a broadband end-fire array antenna conformal to the metal surface.

In order to solve the above technical problems, the technical solution adopted by the present invention is:

A broadband end-fire array antenna conformal to a metal surface, characterized in that it comprises a microwave PCB board, a coplanar pad, a metal pin, and a metallized hole;

A microwave PCB board, wherein the microwave PCB board comprises an upper and lower PCB board, a plurality of radiation patches are etched on the front surface of the upper PCB board, a microstrip feed line is etched on the back surface of the lower PCB board, and a floor is provided between the upper PCB board and the lower PCB board;

A coplanar pad, which is etched on the back side of the lower PCB board and is coplanar with the microstrip feed line;

A metal pin, the metal pin is located at the center of the radiation patch, passes through the upper PCB board and the lower PCB board and is connected to the microstrip feeder;

Metallized holes are distributed on the radiation patch and pass through the upper PCB board to be connected to the floor.

A further technical solution of the present invention is that the radiation patches are arranged in a straight line in order according to their sizes, and their sizes and quantities are related to their operating frequency bands.

A further technical solution of the present invention is as follows: the radiation patch is a metal plane structure, and its shape is circular, elliptical or square.

A further technical solution of the present invention is that the number of the radiation patches is greater than 3, and the spacing between them is between 0.3 wavelengths and 0.5 wavelengths of the operating frequency of each radiation patch itself, and changes according to a fixed ratio.

A further technical solution of the present invention is as follows: the microstrip feed line is a metal plane structure, composed of lines of different widths, and is used to connect radiation patches of different sizes, and its different widths are used to achieve antenna impedance matching.

A further technical solution of the present invention is that the microstrip feed line is in a series-fed form, and the phase of adjacent radiating patches in the corresponding working frequency band is adjusted by bending to achieve end-fire radiation of the antenna.

A further technical solution of the present invention is that the coplanar pad is connected to the ground through a metallized hole and is used for welding the outer skin of the coaxial cable, and the core wire of the coaxial cable is welded to the microstrip feeder.

A further technical solution of the present invention is that the coplanar pad is a rectangular metal coating, which is placed at one end of the downward vertical position corresponding to the smallest radiation patch and maintains a certain distance from the microstrip feed line.

A further technical solution of the present invention is that the metallized holes are arranged circumferentially on the radiation patch.

The beneficial effects of the present invention are:

The present invention provides a conformal broadband end-fire array antenna on a metal surface, which uses a microstrip patch antenna operating in a miniaturized base mode (or static mode) as a unit to form a planar logarithmic periodic antenna array in series to form broadband directional radiation, and the antenna polarization is vertical polarization (the polarization direction is perpendicular to the carrier surface), and directional radiation is formed in the broadband along the tangent direction of the carrier surface. The present invention solves the design problem of the coplanar end-fire of a broadband vertically polarized antenna, and has the advantages of simple structure, good concealment, no influence on the aerodynamic characteristics of the carrier appearance, stable and reliable electrical performance, and easy mass production.

Compared with the prior art, the present invention uses a circular microstrip patch antenna fed from the bottom center, and realizes the sequential lag of the phase of the smaller radiation patch through the bent microstrip feed line, and can realize the antenna design of broadband directional radiation in the tangent direction of the carrier surface, specifically:

1. The present invention adopts microstrip line series feeding and adjusts the phase of different radiation units through the microstrip line to achieve broadband vertical polarization directional radiation along the carrier surface.

2. The present invention uses radiation patches of different sizes, which can work in different frequency bands. In the bandwidth of the entire antenna broadband operation, radiation patches of different sizes radiate in different frequency bands to achieve broadband operation.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

FIG. 1 is an overall structural diagram of an antenna according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating the structure of an antenna according to an embodiment of the present invention.

FIG. 3 is a diagram showing the voltage standing wave ratio of the antenna according to the technical embodiment of the present invention.

FIG. 4 is a ZOX radiation pattern of the antenna 4.8G according to the technical embodiment of the present invention.

FIG. 5 is a ZOY radiation diagram of the antenna 4.8G according to the technical embodiment of the present invention.

FIG. 6 is a ZOX radiation pattern of the antenna 5.2G according to the technical embodiment of the present invention.

FIG. 7 is a ZOY radiation diagram of antenna 5.2G according to an embodiment of the present invention.

FIG. 8 is a ZOX radiation pattern of the antenna 6.3G according to the technical embodiment of the present invention.

FIG. 9 is a ZOY radiation diagram of antenna 6.3G according to an embodiment of the present invention.

Description of reference numerals:

1-three-layer microwave PCB board, 2-radiation patch, 3-metallized hole, 4-microstrip feed line, 5-coplanar pad, 201-first circular metal patch, 202-second circular metal patch, 203-third circular metal patch, 204-fourth circular metal patch, 205-fifth circular metal patch, 206-sixth circular metal patch, 304-first metal pin, 308-second metal pin, 312-third metal pin, 316-fourth metal pin, 320-fifth metal pin, 324-sixth metal pin, 301-first metallized hole, 302 - second metallized hole, 303 - third metallized hole, 305 - fourth metallized hole, 306 - fifth metallized hole, 307 - sixth metallized hole, 309 - seventh metallized hole, 310 - eighth metallized hole, 311 - ninth metallized hole, 313 - tenth metallized hole, 314 - eleventh metallized hole, 315 - twelfth metallized hole, 317 - thirteenth metallized hole, 318 - fourteenth metallized hole, 319 - fifteenth metallized hole, 321 - sixteenth metallized hole, 322 - seventeenth metallized hole, 323 - eighteenth metallized hole.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

The present invention provides a broadband end-fire array antenna conforming to a metal surface, comprising: a three-layer microwave PCB board, a radiation patch, a microstrip feeder, a metalized hole, a metal pin and a coplanar pad. Radiating patches of different sizes are attached to the upper layer (the carrier surface facing outward) of the three-layer microwave PCB board; the middle layer is a floor (copper-covered on the entire surface), the microstrip feeder is attached to the lower layer (the inner side of the carrier surface) of the three-layer microwave PCB board, and the coplanar pad is at one end of the microstrip feeder, which is used to connect the radio frequency cable to the microstrip feeder from the side to feed the radiation patches of different sizes. The broadband directional antenna array conforming to the metal carrier surface of the present invention can be embedded in the carrier surface and the carrier surface is coplanar.

Specifically, in the three-layer microwave PCB board, microwave dielectric boards are used between the upper layer and the middle layer, and between the middle layer and the lower layer. The thickness and dielectric constant of the dielectric layer can be selected according to requirements.

Specifically, the radiation patch is used to excite electromagnetic waves.

Specifically, the radiation patch is a planar structure, and can be circular, elliptical, square, etc., and can be selected according to needs.

Specifically, the number of the radiation patches is generally greater than 3, and their size and number are selected by the required working frequency band. Their size is generally between 0.2 wavelengths and 0.5 wavelengths of the working frequency of each radiation patch itself, and varies according to a fixed ratio.

Specifically, the number of the radiation patches is generally greater than 3, and the spacing between them is generally between 0.3 wavelengths and 0.5 wavelengths of the operating frequency of each radiation patch itself, and varies according to a fixed ratio.

Specifically, the radiation patch is loaded with a plurality of metallized holes, which are distributed on a circumference of a certain radius of the radiation patch and connected to the middle floor. The number and position of the metallized holes can be selected according to requirements.

Specifically, the metal pin is located at the center of the radiation patch, passes through the floor and is connected to the microstrip feed line for feeding the radiation patch, and there is a clearance hole on the floor and is not connected to the floor;

Specifically, the microstrip feed line is composed of meander lines of different widths, and is divided into a phase adjustment section and a connection section, and its width and length are selected according to impedance matching and radiation pattern requirements.

Specifically, the coplanar pad is composed of a rectangular metal sheet and a metallized hole, the metallized hole is connected to the floor, and is used for welding the metal sheath of the radio frequency cable. The size of the coplanar pad can be determined according to the size of the radio frequency cable.

Specifically, the metalized hole is used for short-circuiting and grounding the radiating patch to miniaturize the radiating patch; the metal pin is used to connect the radiating patch with the microstrip feed line to realize power feeding of the radiating patch.

In order to enable those skilled in the art to better understand the present invention, the present invention is described in detail below in conjunction with specific embodiments.

1-2 , an embodiment of a broadband end-fire array antenna with a conformal metal surface is shown in the present invention, which includes five parts: a three-layer microwave PCB board 1, a radiation patch 2, a metallized hole 3, a microstrip feed line 4, and a coplanar pad 5.

The dielectric constant of the three-layer microwave PCB board 1 is 2.65; the thickness of the upper dielectric layer is 0.07 wavelengths, and the thickness of the lower dielectric layer is 0.02 wavelengths.

The radiation patches 201-206 are circular planar metal patches, the largest patch corresponds to 0.2 wavelength of the low frequency working frequency wavelength, and changes in proportion in sequence. The centers of the circular metal patches 201-206 are connected to the microstrip feed line 4 through metal pins 304, 308, 312, 316, 320, 324. Metallized holes 301, 302, 303 are evenly distributed on the circumference of the radiation patch 201 with a certain radius from the center; metallized holes 305, 306, 307 are evenly distributed on the circumference of the radiator patch 202 with a certain radius from the center; metallized holes 309, 310, 311 are evenly distributed on the circumference of the radiator patch 203 with a certain radius from the center; metallized holes 313, 314, 315 are evenly distributed on the circumference of the radiator patch 204 with a certain radius from the center; metallized holes 317, 318, 319 are evenly distributed on the circumference of the active radiator patch 205 with a certain radius from the center; metallized holes 321, 322, 323 are evenly distributed on the circumference of the radiator patch 206 with a certain radius from the center.

The microstrip feed line 4 is a bent, gradient-width planar metal line, as shown in FIG2(d), and is divided into 10 sections 401-410, of which sections 401, 403, 405, 407, and 409 are connected to the radiation patches 201, 202, 203, 204, 205, and 206 through metal pins 304, 308, 312, 316, 320, and 324; section 402 generates a 180° phase shift according to the operating frequency band of patches 201-206, and so on. The additional 180° phase shift makes the smaller radiation patch have a delayed phase to achieve directional end-fire of the array antenna.

The coplanar pad 5 is placed at one end of the microstrip feed line 4 and is 0.5 mm away from the end of the microstrip feed line.

The overall structure of the antenna of the technical embodiment of a conformal broadband end-fire array antenna on a metal surface is shown in Figure 1. The high-frequency current is fed into the microstrip feeder 4 through the RF cable, and is fed to the radiation patches of different frequency bands through the microstrip feeder. The delay between the feeding direction and the 180° phase determines that the high-frequency directional radiation patch has a delayed phase lag characteristic, thereby generating a directional end-fire. The operation of the radiation patches in different effective areas forms a broadband characteristic. This method can be used to design a broadband directional antenna array conformal to the surface of a metal carrier.

The results of the technical embodiments of the present invention are further illustrated by simulation:

1. Simulation content:

Please refer to FIG. 3 to FIG. 9 , the voltage standing wave ratio, directivity pattern and gain characteristics of the antenna of the above technical embodiment are simulated and calculated using simulation software.

2. Simulation results:

FIG3 is a characteristic of the voltage standing wave ratio varying with the operating frequency obtained by simulating the antenna of the technical embodiment. It can be seen from FIG3 that the antenna 1 of the embodiment of the present invention operates in the C frequency band, and the directional diagram can achieve a relative bandwidth of 27%.

4 to 9 are the relevant directional diagrams of the antenna of the embodiment of the antenna of the present invention. The antenna of the embodiment of the antenna of the present invention can achieve a gain of more than 5.5 to 8.8 dB in an infinite horizontal plane (XOY plane) within the working frequency band (4.8 GHz-6.3 GHz).

The simulation results show that an array of radiating patches of different sizes connected by microstrip feed lines can realize a broadband end-fire array design and can be designed coplanar with the carrier surface. The antenna of the technical embodiment of the present invention can meet the design requirements of a coplanar antenna with broadband directional radiation along the carrier surface.

The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be included in the protection scope of the present invention.

Claims (9)

1. The broadband end-fire array antenna with the conformal metal surface is characterized by comprising a microwave PCB, a coplanar bonding pad, metal pins and metallized holes;

the microwave PCB comprises an upper layer PCB and a lower layer PCB, a plurality of radiation patches are etched on the front surface of the upper layer PCB, microstrip feeder lines are etched on the back surface of the lower layer PCB, and a floor is arranged between the upper layer PCB and the lower layer PCB;

The coplanar bonding pad is etched on the back surface of the lower PCB and is coplanar with the microstrip feeder line;

The metal pin is positioned at the center of the radiation patch and penetrates through the upper-layer PCB and the lower-layer PCB to be connected with the microstrip feeder line;

and the metallized holes are distributed on the radiation patch and penetrate through the upper PCB to be connected with the floor.

2. A metallic surface conformal broadband end-fire array antenna according to claim 1, wherein said radiating patches are sequentially aligned in order of size and number in relation to their operating frequency band.

3. A wideband end-fire array antenna of claim 2 wherein said radiating patches are metallic planar structures having a circular, elliptical or square shape.

4. A metallic surface conformal broadband end-fire array antenna according to claim 3, wherein said radiating patches are greater than 3 in number, with a spacing between 0.3 wavelength and 0.5 wavelength of each self radiating patch operating frequency, and varying in fixed proportion.

5. The broadband end-fire array antenna of claim 1, wherein the microstrip feed is a metal planar structure, and is formed of lines of different widths for connection to radiating patches of different sizes, the different widths being used to achieve antenna impedance matching.

6. The wideband end-fire array antenna of claim 5, wherein the microstrip feed is in the form of a series feed, and the antenna end-fire radiation is achieved by bending and adjusting the phase of adjacent radiating patches of the radiating patches in the corresponding operating frequency band.

7. A wideband end-fire array antenna of claim 1 wherein the coplanar pads are connected to the floor by metallized holes for soldering the outer skin of the coaxial cable, the core of the coaxial cable being soldered to the microstrip feed line.

8. The wideband end-fire array antenna of claim 7 wherein said coplanar pads are rectangular metal cladding and are positioned at a distance from said microstrip feed line corresponding to one end of a minimum radiating patch in a downward vertical position.

9. A wideband end-fire array antenna of claim 1 wherein said metallized holes are circumferentially aligned on the radiating patch.