CN111900536A - A Microstrip Antenna with a Laminated Structure - Google Patents

Abstract

The invention discloses a microstrip antenna with a laminated structure, which belongs to the technical field of antennas. The antenna includes a first dielectric layer, a second dielectric layer, a third dielectric layer and a radio frequency connector which are arranged in sequence from top to bottom; wherein the first dielectric layer, the second dielectric layer and the third dielectric layer are multi-layer printed boards The processing technology realizes the close adhesion between the layers and realizes the integrated design of the antenna structure. The outer conductor of the RF connector is welded on the metal ground on the lower surface of the third dielectric layer to achieve a reliable and fixed connection with the antenna radiator. The RF connector Complete the reception and transmission of microwave signals. The invention has the characteristics of miniaturization, wide bandwidth, compact structure, and can realize dual-frequency circular polarization radiation.

Description

A Microstrip Antenna with a Laminated Structure

technical field

The present invention relates to the field of antenna technology, in particular to a microstrip antenna with a stacked structure.

Background technique

At present, the spectrum of communication in the field of satellite communication is getting wider and wider, and the requirements for radio frequency terminals are getting higher and higher, which requires the working bandwidth of the antenna to be gradually widened. Satellite communication and navigation communication systems often require equipment with functions of receiving and sending signals, and the frequency bands for sending and receiving signals are different. The requirements for antennas are multi-frequency and broadband operation; with the rapid development of phased array antenna technology, its unique Some technical advantages make it more and more valued by engineers and technicians. Antenna radiation unit is one of the key technical components of phased array antenna, and its excellent performance directly affects the quality of satellite communication.

At present, circularly polarized microstrip antennas mainly have the following forms:

1. Diagonal tangential circularly polarized microstrip antenna: This form of antenna has a simple structure and a low profile, but the antenna axis ratio and standing wave bandwidth are less than 2%.

2. The circularly polarized microstrip antenna form of the integrated electric bridge, the microstrip antenna of this form has a wider axial ratio and wider standing wave bandwidth, usually less than 3dB, the axial ratio bandwidth is greater than 15%, and the standing wave bandwidth less than 2 is greater than 20%, but The external circularly polarized bridge occupies a large space, the feeder is long, and the differential loss is large, which is not conducive to the integrated design of the antenna and the network.

3. Slot-coupled circularly polarized microstrip antenna. Compared with the traditional circularly polarized microstrip antenna, this form of circularly polarized microstrip antenna has the characteristics of wider impedance and wider axial ratio bandwidth, but due to the asymmetry of the slot structure, It is often necessary to load isolation resistors to achieve a wider axial ratio bandwidth, which leads to two problems: on the one hand, the isolation resistors need to be manually welded. When the array is large, it requires a huge workload, and it is difficult to ensure the consistency of the unit welding. On the other hand, the isolation resistance will produce a certain amount of differential loss, resulting in a decrease in radiation gain to varying degrees.

The above types of circularly polarized microstrip antennas have their own advantages and disadvantages. Although individual indicators have better characteristics, their common defect is that they cannot meet the technical requirements of miniaturized wide-band operation, especially as a phased array antenna for wide-band and multi-frequency operation. unit.

SUMMARY OF THE INVENTION

In view of this, the present invention provides a microstrip antenna with a stacked structure, which has the characteristics of miniaturization, wide bandwidth, compact structure and dual-frequency circularly polarized radiation

In order to achieve the above object, the technical scheme adopted by the present invention is:

A microstrip antenna with a stacked structure includes a radio frequency connector, and also includes a first dielectric layer, a second dielectric layer and a third dielectric layer arranged in sequence from top to bottom;

The main body of the first dielectric layer is a square first dielectric plate; the main body of the second dielectric layer is a square second dielectric plate; vibrator arms are provided at two opposite corner positions on the surface of the first dielectric plate; There are vibrator arms at the other two opposite corner positions on the upper surface of the second dielectric plate; on the same surface, the two vibrator arms are symmetrical about the center point of the upper surface of the corresponding dielectric plate, and the inner vertices of the two vibrator arms are connected by a horizontal clamp The angle is 45°;

The vibrator arm is a rectangular ring structure with an opening, and the long side of the vibrator arm is parallel to one side of the corresponding dielectric plate; the openings are all located on the inner wide side of the corresponding rectangular ring structure and are close to the inner long side, and the openings are is one third of the length of the broad side;

The main body of the third medium layer is a third medium plate, and a microstrip power divider is arranged on the upper surface of the third medium plate. The microstrip power divider includes a synthesis port and two output ports. The surface is provided with a metal ground; the synthetic port is connected with the inner conductor of the radio frequency connector, and the metal ground is connected with the outer conductor of the radio frequency connector;

It also includes a metal via group composed of metal vias arranged in a straight line, each metal via group is located on the inner long side of the corresponding vibrator arm and close to the opening position, and the metal via group is parallel to the inner long side and perpendicular on the first dielectric board; the other end of the metal via group is connected to the metal ground on the lower surface of the third dielectric board;

There are also excitation vias and open via terminals on the upper surface of the first dielectric board and the upper surface of the second dielectric board; the excitation vias and open via terminals on the same surface are located on the outside of the corresponding rectangular ring structure, respectively. And the connection line between the excitation via and the open via terminal and the center of the metal via group on the corresponding rectangular ring structure is perpendicular to its inner long side; the excitation vias on the upper surface of the first dielectric board and the excitation vias on the upper surface of the second dielectric board are The projection of the connection line of the via hole is parallel to the inner long side of the corresponding rectangular ring structure;

The excitation vias and the open via terminals are connected by jumper strip lines on the corresponding surfaces; the excitation vias and the open via terminals are both perpendicular to the first dielectric plate; the other end of each excitation via is connected to the microstrip power divider The other end of each open-circuit via terminal is located above the metal ground and is not in contact with the metal ground.

Further, the metal via group includes four metal vias arranged in a straight line.

The beneficial effect that the present invention adopts the above-mentioned technical scheme to produce is:

1. Compared with the mechanically processed antenna, the present invention adopts the multi-layer printed board processing technology, which has the characteristics of compact structure, easy integration and small electrical size.

2. The present invention adopts the method of coupling feeding to improve the impedance bandwidth of the antenna, and a pair of notch-type vibrators arranged in layers realizes the distribution of eddy currents of different frequencies, thereby realizing dual-frequency circularly polarized common-aperture radiation.

Description of drawings

FIG. 1 is a schematic structural diagram of an embodiment of the present invention.

FIG. 2 is a schematic structural diagram of the upper surface of the first dielectric plate in FIG. 1 .

FIG. 3 is a schematic structural diagram of the upper surface of the second dielectric plate in FIG. 1 .

FIG. 4 is a schematic structural diagram of the upper surface of the third dielectric plate in FIG. 1 .

In the figure: 1, the first dielectric layer, 2, the second dielectric layer, 3, the third dielectric layer, 6, the vibrator arm, 7, the metal via group, 8, the excitation via, 9, the metal via group, 10 , Open via terminal, 12, Output port, 13, Jumper strip line, 14, Vibrator arm, 15, Metal via group, 16, Excitation via, 18, Jumper strip line, 19, Metal via group, 20, open circuit via terminal, 22, output port, 23, synthesis port, 24 microstrip power divider.

Detailed ways

Hereinafter, the present invention will be further described with reference to the accompanying drawings and specific embodiments.

A microstrip antenna with a stacked structure includes a radio frequency connector, and also includes a first dielectric layer, a second dielectric layer and a third dielectric layer arranged in sequence from top to bottom;

The main body of the first dielectric layer is a square first dielectric plate; the main body of the second dielectric layer is a square second dielectric plate; vibrator arms are provided at two opposite corner positions on the surface of the first dielectric plate; There are vibrator arms at the other two opposite angular positions on the upper surface of the second dielectric plate; the horizontal included angle of the line connecting the inner vertices of the two vibrator arms on the same surface is 45°;

The vibrator arm is a rectangular ring structure with an opening, and the long side of the vibrator arm is parallel to one side of the corresponding dielectric plate; the openings are all located on the inner wide side of the corresponding rectangular ring structure and are close to the inner long side, and the openings are The length of is one-third of the length of the broad side; the two oscillator arms are symmetrical about the center point of the upper surface of the corresponding dielectric plate;

The main body of the third medium layer is a third medium plate, and a microstrip power divider is arranged on the upper surface of the third medium plate. The microstrip power divider includes a synthesis port and two output ports. The surface is provided with a metal ground; the synthetic port is connected with the inner conductor of the radio frequency connector, and the metal ground is connected with the outer conductor of the radio frequency connector;

It also includes a metal via group composed of linearly arranged metal vias, each metal via group is located on the inner long side of the corresponding vibrator arm and close to the opening position, and the metal via group is parallel to the inner long side and perpendicular on the first dielectric board; the other end of the metal via group is connected to the metal ground on the lower surface of the third dielectric board;

There are also excitation vias and open via terminals on the upper surface of the first dielectric board and the upper surface of the second dielectric board; the excitation vias and open via terminals on the same surface are located on the outside of the corresponding rectangular ring structure, respectively. And the connection line between the excitation via and the open via terminal and the center of the corresponding rectangular annular structure is perpendicular to its inner long side; the connection line between the excitation via on the upper surface of the first dielectric board and the excitation via on the upper surface of the second dielectric board The projection of is parallel to the inner long side of the corresponding rectangular ring structure;

The excitation vias and the open via terminals are connected by jumper strip lines on the corresponding surfaces; the excitation vias and the open via terminals are both perpendicular to the first dielectric plate; the other end of each excitation via is connected to the microstrip power divider The other end of each open-circuit via terminal is located above the metal ground and is not in contact with the metal ground.

Further, the metal via group includes four metal vias arranged in a linear array.

The following is a more specific embodiment:

As shown in FIGS. 1 to 4 , this embodiment includes a first dielectric layer 1 , a second dielectric layer 2 , a third dielectric layer 3 , and a radio frequency connector, wherein the first dielectric layer 1 , the second dielectric layer 2 , the third dielectric layer 2 , the The dielectric layer 3 adopts the multi-layer printed board processing technology to realize the close adhesion between the layers and realize the integrated design of the antenna structure. The reliable and fixed connection of the body, and the radio frequency connector completes the reception and transmission of microwave signals.

This embodiment can work in two frequency bands, high and low at the same time. The high frequency band is represented by F _h and the low frequency band is represented by F _l .

The first dielectric layer 1 is located on the uppermost layer, with a square cross-section. The upper surface is provided with two rectangular ring-shaped vibrator arms ₆ working in the low frequency band F1. The vibrator arm 6 is deviated from the geometric center point of the surface of the dielectric layer 1 , and the line connecting the vertices of the two vibrator arms 6 close to the geometric center forms an included angle of 45° with the horizontal direction.

The vibrator arm 6 has a rectangular ring structure with an opening, the line width of the rectangular ring is 0.015λ _l (λ _l is the wavelength corresponding to the center frequency of the F ₁ frequency band), the length of the long side is 0.33λ _l , and the length of the short side is 0.17λ _l .

The metal via group 7 runs through between the dielectric layer 1 and the dielectric layer 3, one end of which is vertically fed to the starting end of a vibrator arm 6 (the starting end is the vertex close to the geometric center), and is arranged along the long side of the rectangular ring vibrator , the other end is electrically connected to the third layer of dielectric metal ground to form the overall radiation structure of the antenna structure, and the corresponding vibrator arms are also set in the same way;

An opening is provided at the position of the short side adjacent to the initial end of the vibrator arm 6 to cut off the current so as to excite the resonant current.

The metal via hole group 7 has a via hole diameter of 1 mm and a spacing of 0.3 mm. Its function is to conduct the metal ground and the vibrator arm 6 to form an overall radiation structure of the antenna structure.

An excitation via hole 8 is arranged adjacent to the metal via hole group 7, and its position is deviated from the geometric centerline of the metal via hole group 7, and the gap is about 0.5mm; The output port 12 of the power divider is connected, and the other end is connected to one end of the jumper strip line 13 .

An open via terminal 10 is arranged adjacent to the metal via group 9, which is consistent with the position setting of the via array 7 and the excitation via 8 above. 0.05λ _l , the lower surface of the dielectric layer 3 is not in contact with the metal ground.

On the upper surface of the dielectric layer 1, a strip line jumper strip line 13 is arranged between the excitation via hole 8 and the open via hole terminal 10, so that the two can conduct signals.

Similarly, the antenna radiation structure operating in the F _h frequency band is set at the orthogonal position of the F _l frequency band antenna, and the two rectangular ring-shaped vibrator arms 14 are located on the upper surface of the second dielectric layer 2, and the two are about the geometric center of the surface of the dielectric layer. The points are 180° rotationally symmetrical, the vibrator arm 14 deviates from the geometric center point of the upper surface of the second dielectric layer 2 , and the line connecting the vertices of the two vibrator arms 14 close to the geometric center is 135 degrees from the horizontal direction.

One end of the metal via group 15 is vertically fed to the starting end of the vibrator arm 14, and the other end is electrically connected to the metal ground on the lower surface of the third dielectric layer 3, and the two constitute half of the overall radiation structure of the F _h -band antenna. Another 1/2 part of the radiation structure is arranged at a 180° rotationally symmetrical position.

Further, the vibrator arm 14 has a rectangular ring structure, the ring line width is 0.011λ _h (λ _h is the wavelength corresponding to the center frequency of the F _h frequency band), the long side length is 0.3λ _h , and the short side length is 0.15λ _h .

Further, an opening is also provided at the position of the short side of the vibrator arm 14 close to the vertex of the geometric center, so as to cut off the current and excite the resonant current.

An excitation via hole 16 is arranged adjacent to the metal via hole group 15, and its starting end is connected to the output port 22 of the microstrip power divider 24, and the other end is connected to one end of the jumper strip line 18;

Further, an open-circuit via terminal 20 is disposed adjacent to the metal via group 19, the length of which is shorter than that of the excitation via 16, and is not in contact with the metal ground.

Further, on the upper surface of the second dielectric layer 2, a jumper strip line 18 is provided between the excitation via hole 16 and the open via hole terminal 20, so that the two can conduct signals.

In this way, the signal of the F _l -band antenna and the signal of the F _h -band antenna enter the input port of the microstrip power divider 24 through the excitation via hole, and complete the power synthesis, which is input through the synthesis port 23 and sent to the radio frequency connector.

The layered structure microstrip antenna device mainly includes two parts: a microwave medium and a radio frequency connector. The microwave medium layer adopts a multi-layer board processing technology. The inside of the medium is a multi-layer medium and metallized vias. The communication system has obvious technical advantages for the structure and electrical technical requirements of the antenna components.

The working principle of the layered microstrip antenna is as follows: when the transmitted signal enters the radio frequency connector 4, it enters the synthesis port 23 of the microstrip power divider 24, and the power is divided into two signals through the output ports 12 and 22, respectively. In the high frequency band F _h antenna structure and the low frequency band F _l antenna structure, the low frequency end antenna structure is taken as an example to illustrate:

The signal enters the excitation via 8 through the output port 12, and the excitation via 8 couples a part of the energy to the metal via group 7 by means of coupling, and the metal via transmits the signal to one arm of the vibrator arm 6, where the electromagnetic wave signal is transmitted. The upper surface oscillates, the surface current on the vibrator arm of the open structure is a rotating field, and the excited via 8 transmits a part of the energy to the open via terminal 10 through the jumper strip line 13, and at the same time, the coupled metal via group 9 transmits the signal to the vibrator The other arm 8 is connected to the arm 6 and an oscillation signal is excited, and the currents on the surface of the pair of vibrator arm 6 and the vibrator arm 8 realize in-phase power synthesis in space and radiate to free space.

The same as the above principle, the F _h -band antenna is located on the upper surface of the second dielectric layer 2, and its radiation signal is radiated to the free space through the first dielectric layer 1, and the signals of the two-band antenna are synthesized in the microstrip power divider 24, via The radio frequency connector receives and sends signals, so as to realize free receiving and sending of high (F _h ) and low (F _l ) frequency bands.

It should be understood that the above descriptions of the specific embodiments of the present patent are merely exemplary descriptions for the convenience of those of ordinary skill in the art to understand the solutions of the present patent, and do not imply that the protection scope of the present patent is only limited to these examples. Those of ordinary skill in the art can, on the premise of fully understanding the technical solution of this patent, without any creative work, combine technical features, replace some technical features, add more technical features, etc., to obtain more specific implementations, all of which are within the scope of the patent claims, therefore, these new specific implementations should also be within the protection scope of this patent .

Claims (2)

1. A microstrip antenna with a laminated structure comprises a radio frequency connector, and is characterized by further comprising a first dielectric layer (1), a second dielectric layer (2) and a third dielectric layer (3) which are sequentially arranged from top to bottom;

the main body of the first dielectric layer is a square first dielectric plate; the main body of the second dielectric layer is a square second dielectric plate; vibrator arms are arranged at two opposite angular positions of the upper surface of the first medium plate; vibrator arms are arranged at the other two opposite angular positions on the upper surface of the second medium plate; the two oscillator arms on the same surface are symmetrical about the central point of the upper surface of the corresponding dielectric plate, and the horizontal included angle of the connecting line of the inner vertexes of the two oscillator arms is 45 degrees;

the vibrator arm is of a rectangular annular structure with an opening, and the long edge of the vibrator arm is parallel to one side of the corresponding dielectric plate; the openings are positioned on the inner wide side of the corresponding rectangular annular structure and are tightly attached to the inner long side, and the length of each opening is one third of that of the wide side;

the main body of the third dielectric layer is a third dielectric plate, the upper surface of the third dielectric plate is provided with a microstrip power divider (24), the microstrip power divider comprises a synthesis port and two output ports, and the lower surface of the third dielectric plate is provided with a metal ground; the synthesis port is connected with an inner conductor of the radio frequency connector, and the metal ground is connected with an outer conductor of the radio frequency connector;

the metal through hole groups are respectively positioned on the long side of the inner side of the corresponding vibrator arm and are tightly attached to the opening position, and the metal through hole groups are parallel to the long side of the inner side and are vertical to the first dielectric plate; the other end of the metal via hole group is communicated with a metal ground on the lower surface of the third dielectric plate;

excitation via holes and open-circuit via hole terminals are arranged on the upper surface of the first dielectric plate and the upper surface of the second dielectric plate; the exciting via holes and the open-circuit via hole terminals on the same surface are respectively positioned on the outer sides of the corresponding rectangular annular structures, and the connecting lines of the exciting via holes and the open-circuit via hole terminals and the centers of the metal via hole groups on the corresponding rectangular annular structures are vertical to the long sides of the inner sides of the exciting via holes and the open-circuit via hole terminals; the projection of the connecting line of the excitation through hole on the upper surface of the first dielectric plate and the excitation through hole on the upper surface of the second dielectric plate is parallel to the inner long edge of the corresponding rectangular annular structure;

the excitation via hole and the open via hole terminal are connected through a jumper strip line on the corresponding surface; the excitation via hole and the open via hole terminal are both vertical to the first dielectric plate; the other end of each excitation through hole is connected with the corresponding output port of the microstrip power divider; the other end of each open via terminal is located above and not in contact with the metal ground.

2. A microstrip antenna according to claim 1 wherein the set of metal vias comprises 4 metal vias arranged in a line.

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