CN115986401B - Low-profile high-isolation receiving and transmitting common-port-surface dual-frequency phased array antenna - Google Patents

Abstract

The invention provides a low-profile high-isolation receiving and transmitting common-port-surface dual-frequency phased array antenna, which consists of a plurality of low-frequency antenna units and high-frequency antenna units which are arranged in a crossing manner; the low-frequency antenna unit comprises a low-frequency receiving antenna and a filtering component which are connected; the low-frequency receiving antenna is a microstrip antenna and at least comprises a radiator and a feed body, wherein the outer contour shape of the radiator is saw-tooth-shaped. The invention adopts various decoupling modes at the same time: the low-frequency antenna unit with the self-filtering characteristic is adopted, and the different-frequency isolation degree is improved under the condition that the height/thickness of the antenna is not increased through the cascade filtering component; the high-frequency isolation of the low-frequency receiving antenna is further improved by changing the outline shape of the radiator of the low-frequency receiving antenna into a saw-tooth shape; the isolation degree of the low frequency of the high frequency transmitting antenna is improved through the isolation wall with the coupling piece arranged at the periphery of the high frequency transmitting antenna. The invention effectively solves the problem of mutual interference caused by the difference of isolation between high and low frequency antenna units in the common-port surface antenna.

Description

A low-profile, high-isolation dual-frequency phased array antenna with a common interface for receiving and transmitting

Technical field

The present invention relates to the field of satellite communication antennas, and more specifically, to a low-profile and high-isolation dual-frequency phased array antenna for receiving and transmitting in the same plane.

Background technique

Phased array antenna refers to an antenna that changes the shape of the pattern by controlling the feed phase of the radiating unit in the array antenna. Controlling the phase can change the direction of the maximum value of the antenna pattern to achieve the purpose of beam scanning. Generally speaking, a phased array antenna consists of multiple antenna elements uniformly arranged in order to form an antenna array. In a phased array antenna, if the receiving antenna array and the transmitting antenna array are distributed in the same physical plane, it is called a co-plane antenna array. It is an antenna array proposed to reduce the size and weight of wireless equipment. In a co-oral planar antenna array, the distance between the receiving antenna array and the transmitting antenna array is only a few tenths or even a few hundredths of that of the split-port planar antenna array. In order to reduce the mutual interference problem between the transmitting and receiving antennas, The isolation between various systems needs to be improved.

Contents of the invention

The present invention aims to overcome at least one defect of the above-mentioned prior art and provide a low-profile, high-isolation receiving and transmitting co-oral plane dual-frequency phased array antenna to solve the problems in the existing co-oral plane antenna array. The isolation between systems is not high, causing mutual interference between transmitting and receiving antennas.

The technical solutions adopted by the present invention include:

The present invention provides a low-profile and high-isolation dual-frequency phased array antenna with a common interface for receiving and transmitting, which is composed of several low-frequency antenna units and high-frequency antenna units arranged in a cross arrangement; the low-frequency antenna unit includes a connected A low-frequency receiving antenna and a filter component; the low-frequency receiving antenna is a microstrip antenna, including at least a radiator and a feeder, and the outer contour shape of the radiator is a sawtooth shape.

The phased array antenna provided by the present invention is a co-oral plane antenna array. The high-frequency antenna unit and the low-frequency antenna unit are arranged on the same physical surface in a cross-arranged manner. In order to improve the isolation between the high-frequency and low-frequency antenna units, the low-frequency antenna The unit itself includes a connected low-frequency receiving antenna and filter components, that is, the low-frequency antenna unit has its own filtering characteristics. By cascading filter components, the inter-frequency isolation is improved without increasing the height/thickness of the antenna. Secondly, the low-frequency receiving antenna is a microstrip antenna with a double-layer microstrip structure, including a radiator and a feeder. The outer contour shape of the radiator is a sawtooth shape. The radiator with this outer contour shape is conducive to improving the performance of the low-frequency receiving antenna. High-frequency isolation solves the problem of poor isolation and mutual interference caused by the close distance between high- and low-frequency antenna units in a common-port phased array antenna.

Further, the high-frequency antenna unit includes a high-frequency transmitting antenna and a coupling-piece isolation wall; the high-frequency antenna unit and the low-frequency antenna unit are isolated by a coupling-piece isolation wall.

The high-frequency antenna unit includes a high-frequency transmitting antenna and an isolation wall with a coupling piece, which is used to improve the low-frequency isolation of the high-frequency transmitting antenna and reduce the possibility of mutual interference between high-frequency and low-frequency antenna units.

Further, in the high-frequency antenna unit, the isolation wall with coupling piece surrounds the high-frequency transmitting antenna.

The high-frequency transmitting antenna is located in an isolation wall with a coupling piece and is surrounded by an isolation wall with a coupling piece, which is conducive to further improving the isolation between the high-frequency transmitting antenna and the low-frequency antenna unit.

Further, the filter component is provided in a gap between the low-frequency receiving antenna and the high-frequency antenna unit, below the low-frequency receiving antenna, or on the back side of the low-frequency receiving antenna.

The filter component of the low-frequency antenna unit is located in the gap between the phased array antenna, such as the gap between the high- and low-frequency transmitting and receiving antennas, below the low-frequency receiving antenna, or on the back of the antenna board of the low-frequency receiving antenna. The position does not affect the high- and low-frequency transmitting and receiving antennas. .

Further, the filtering component is a band-rejection filter with a quarter-wavelength open-circuit branch.

Further, in the low-frequency receiving unit, the band-stop filter is connected to the low-frequency receiving antenna through a transition structure, and the transition structure is used to convert the strip line of the band-stop filter into a microstrip line. .

The low-frequency receiving antenna is a microstrip antenna, and the connection to the band-stop filter is achieved through a transition structure that converts a strip line into a microstrip line.

Further, the low-frequency antenna units are arranged along the vertical and horizontal directions, and the high-frequency antenna units are arranged along the ±45° direction.

In the co-orbit planar phased array antenna, the low-frequency antenna units are arranged in the vertical and horizontal directions, and the high-frequency antenna units are arranged in the ±45° direction, realizing the cross arrangement of high- and low-frequency antenna units, and making the co-orbit planar phased array antenna The position arrangement of the antenna units is more compact and reasonable.

Furthermore, the low-frequency antenna units are separated by 0.4-0.6 wavelengths, and the high-frequency antenna units are separated by 0.4-0.6 wavelengths.

Compared with the prior art, the beneficial effects of the present invention are:

The present invention provides a low-profile, high-isolation receiving and transmitting dual-frequency phased array antenna with a common port. In order to improve the isolation between high- and low-frequency transceiver antenna units, the present invention adopts a variety of decoupling methods at the same time: First, the low-frequency antenna unit has its own filtering characteristics through the filter component connected to the low-frequency receiving antenna. The filter component improves inter-frequency isolation without increasing the height/thickness of the antenna. Secondly, by changing the outer contour shape of its radiator to a sawtooth shape, the high-frequency isolation of the low-frequency receiving antenna is further improved. For the high-frequency antenna unit, the low-frequency isolation of the high-frequency transmitting antenna is improved through an isolation wall with a coupling plate located around the high-frequency transmitting antenna. In the present invention, through ingenious shape design and the addition of filter components and isolation walls, the problem of poor isolation and mutual interference caused by the close distance between high and low frequency antenna units in the common-port plane phased array antenna is effectively solved.

Description of the drawings

Figure 1 is a schematic diagram of the overall composition of a surface antenna array in Embodiment 1 of the present invention.

FIG. 2 is a schematic diagram of the arrangement of the low-frequency antenna unit 100 and the high-frequency antenna unit 200 in Embodiment 1 of the present invention.

FIG. 3 is a schematic structural diagram of the low-frequency antenna unit 100 and the high-frequency antenna unit 200 in Embodiment 1 of the present invention.

FIG. 4 is a schematic diagram comparing the antenna isolation curves of whether the low-frequency receiving antenna 110 is connected to the filter component 120 in Embodiment 1 of the present invention.

FIG. 5 is a schematic structural diagram of the outer contour shape of the radiator 111 in Embodiment 1 of the present invention.

FIG. 6 is a schematic diagram comparing the antenna isolation curves of whether the outer contour shape of the radiator 111 is a zigzag shape in Embodiment 1 of the present invention.

FIG. 7 is a schematic diagram comparing antenna isolation curves in Embodiment 1 of the present invention whether the outer contour shape of the radiator 111 is zigzag and whether the high-frequency antenna unit 200 is added with a coupling-piece isolation wall 220 .

Detailed ways

The drawings of the present invention are only for illustrative purposes and should not be construed as limitations of the present invention. In order to better explain the following embodiments, some components in the drawings will be omitted, enlarged or reduced, which does not represent the size of the actual product; for those skilled in the art, some well-known structures and their descriptions in the drawings may be omitted. Understandable.

Example 1

This embodiment provides a low-profile, high-isolation receiving and transmitting co-oral plane dual-frequency phased array antenna, which is mainly used in low-orbit space satellite communication systems and satellite earth ground station receiving communication systems. The dual-frequency phased array antenna provided in this embodiment is a common plane antenna array, that is, the high-frequency antenna and the low-frequency antenna are distributed in the same physical plane. Since the spacing between high- and low-frequency antennas is small in a co-oral planar antenna array, the isolation between the two antennas needs to be increased to ensure that there will be no mutual interference between the two antennas.

As shown in Figure 1, the dual-frequency phased array antenna provided in this embodiment is composed of several low-frequency antenna units 100 and several high-frequency antenna units 200. In the co-oral plane antenna, the low-frequency antenna unit 100 and the high-frequency antenna unit 200 are arranged crosswise, with compact location and small spacing. The low-frequency antenna unit 100 includes a low-frequency receiving antenna 110, and the high-frequency antenna unit 200 includes a high-frequency transmitting antenna 210.

In a specific implementation, as shown in FIGS. 1 and 2 , the low-frequency antenna units 100 are arranged along the vertical and horizontal directions, and the high-frequency antenna units 200 are arranged along the ±45° direction, thereby forming a compact and reasonable criss-crossing. arrangement method.

The spacing between two adjacent low-frequency antenna units 100 is the first spacing. The value of the first spacing ranges from 20 mm to 50 mm. The low-frequency antenna units 100 are separated by 0.4 to 0.6 wavelengths, depending on other factors in the actual situation. The separated wavelengths will be fine-tuned, and the adjustment range is between 0.4 and 0.6. The optimal value is 0.5 wavelengths between the low-frequency antenna units 100.

Since the transmitting antennas 200 are arranged along the ±45° direction, based on the Pythagorean theorem, it can be known that the spacing between two adjacent high-frequency antenna units 200 is the first spacing. times, the high-frequency antenna units 200 are separated by 0.4 to 0.6 wavelengths. The wavelength separation will be fine-tuned according to other factors in the actual situation. The adjustment range is between 0.4 and 0.6. The high-frequency antenna units 200 are separated by 0.5 wavelengths. The wavelength is the ideal value.

As shown in Figure 3, the low-frequency antenna unit 100 specifically includes a low-frequency receiving antenna 110 and a filtering component 120 connected thereto. The filtering component 120 enables the overall low-frequency antenna unit 100 to have its own filtering characteristics, improving the performance of the low-frequency receiving antenna 110 and high-frequency transmission. Isolation between antennas 210.

In a specific implementation, the filter component 120 is a 1/4 wavelength open-circuit branch band-stop filter. The filter component 120 can be disposed in the gap between the low-frequency receiving antenna 110 and the high-frequency transmitting antenna 210, below the low-frequency receiving antenna 110, or on the back of the low-frequency receiving antenna 110 without increasing the height/thickness of the low-frequency antenna unit 100. In this case, it has its own filtering characteristics and improves its inter-frequency isolation. In a specific implementation, when designing the rotation of the low-frequency antenna unit 100 and the high-frequency antenna 200 , the primary consideration should be to avoid overlap between the filter components 120 as much as possible.

FIG. 4 shows antenna isolation curves in two cases whether the low-frequency receiving antenna 110 of the low-frequency antenna unit 100 is connected to the filter component 120 or not. It can be clearly seen from FIG. 4 that when the filter component 120 is added to the low-frequency antenna unit 100 and connected to the low-frequency receiving antenna 110, the isolation of the co-oral antenna is significantly improved.

Specifically, as shown in FIG. 3 , the low-frequency receiving antenna 110 is a microstrip antenna with a double-layer microstrip structure, and the side length ranges from 10 mm to 20 mm. Among them, the double-layer microstrip structure includes a top-layer microstrip patch radiator 111 and a lower-layer feeder 112. In a specific implementation, the lower feeder 112 is a coupled filtered circularly polarized feeder to form a circularly polarized antenna. In the common plane antenna, the low-frequency receiving antenna 110 and the high-frequency transmitting antenna 210 realize left-hand circular polarization and right-hand circular polarization respectively. The low-frequency receiving antenna 110 can be a left-hand circular polarization antenna or a right-hand circular polarization antenna. The frequency transmitting antenna 210 may be a right-hand circularly polarized antenna or a left-hand circularly polarized antenna. In this embodiment, the low-frequency receiving antenna 110 is a right-hand circularly polarized antenna, and the high-frequency transmitting antenna 210 is a left-hand circularly polarized antenna. The operating frequency band of the low-frequency receiving antenna 110 is 3 to 5 GHz, and the operating frequency band of the high-frequency transmitting antenna 210 is 3 to 5 GHz. is 6~8GHz.

As shown in Figure 3, the outer contour shape of the microstrip patch radiator 111 on the top layer is a sawtooth shape, which is composed of several sawtooths of uniform size and spacing. As shown in Figure 5, there are two other radiators suitable for the co-oral planar antenna of this embodiment, and their outer contours are in a uniform sawtooth shape. By designing the outer contour shape of the radiator 111 into a zigzag shape, it is beneficial to improve the high-frequency isolation of the low-frequency receiving antenna 110 .

Figure 6 shows the isolation curves between the low-frequency antenna unit 100 and the high-frequency antenna unit 200 in the two cases. Before the outer contour shape of the radiator 111 is changed, the isolation curves of the low-frequency antenna unit 100 and the high-frequency antenna unit 200 are The lowest frequency point of coupling is located at point m2. After changing the outer contour shape of the radiator 111 of the low-frequency antenna unit 100 to a zigzag shape, the entire coupling curve of the low-frequency antenna unit 100 and the high-frequency antenna unit 200 is translated to the low frequency, thus realizing the adjustment of the antenna. The function of coupling degree within a specific frequency band plays a role in improving high-frequency isolation.

As shown in Figure 3, the low-frequency receiving antenna 110 is connected to the filter component 120 through the feeder 112. Specifically, the low-frequency antenna unit 100 also includes a transition structure 130, which is used to make the band of the filter component 120 The linear structure is transformed into a microstrip structure in the feeder 112, so that the low-frequency receiving antenna 110 and the filter component 120 are connected.

As shown in FIG. 3 , the high-frequency antenna unit 200 includes a high-frequency transmitting antenna 210 and a coupling-piece isolation wall 220 .

The high-frequency transmitting antenna 210 is a microstrip antenna with a double-layer microstrip structure, and the side length ranges from 6 mm to 15 mm. Among them, the double-layer microstrip structure includes a top-layer microstrip patch radiator 211 and a lower-layer feeder 212. In a specific implementation, the lower feeder 212 is a coupled filtered circularly polarized feeder to form a circularly polarized antenna. In the common plane antenna, the low-frequency receiving antenna 110 and the high-frequency transmitting antenna 210 realize left-hand circular polarization and right-hand circular polarization respectively. The low-frequency receiving antenna 110 can be a left-hand circular polarization antenna or a right-hand circular polarization antenna. The frequency transmitting antenna 210 may be a right-hand circularly polarized antenna or a left-hand circularly polarized antenna.

The isolation wall 220 with a coupling piece is used to isolate the high-frequency transmitting antenna 210 and the low-frequency receiving antenna 110, and improve the low-frequency isolation of the high-frequency transmitting antenna 210. In a preferred embodiment, in order to ensure a high degree of isolation between the high-frequency transmitting antenna 210 and the low-frequency receiving unit 110, the high-frequency transmitting antenna 210 is surrounded by a coupling-piece isolation wall 220, that is, the high-frequency transmitting antenna 210 is disposed on the coupled strip. Within the wall 220.

In a specific embodiment, the coupling degree between the low-frequency receiving antenna 110 and the high-frequency transmitting antenna 210 can be adjusted by controlling the size of the coupling piece in the isolation wall 220 with coupling pieces and the distance between it and the antenna floor. And improve the low-frequency isolation of the high-frequency transmitting antenna 210.

As shown in FIG. 6 , the antenna isolation curves between two low-frequency antenna units 100 and high-frequency antenna units 200 are shown whether the outer contour shape of the radiator 111 is changed to a zigzag shape, and the outer contour shape of the radiator 111 is not changed. Previously, the lowest coupling frequency point of the low-frequency antenna unit 100 and the high-frequency antenna unit 200 was located at point m2. After changing the outer contour shape of the radiator 111 of the low-frequency antenna unit 100 to a zigzag shape, the low-frequency antenna unit 100 and the high-frequency antenna unit 200 The entire coupling curve shifts to low frequency, thereby realizing the function of adjusting the coupling degree between antennas in a specific frequency band, and improving high-frequency isolation.

Figure 7 shows the antenna isolation curves in two cases whether the co-oral plane antenna adopts a zigzag-shaped radiator 111 and an isolation wall 220 with a coupling piece is provided around the high-frequency transmitting antenna 210. It can be clearly seen from Figure 7 that the isolation of the co-oral plane antenna is significantly improved by adding a coupling plate isolation wall 220 around the high-frequency transmitting antenna 210 and using a zigzag-shaped radiator 111.

This embodiment provides a low-profile, high-isolation receiving and transmitting dual-frequency phased array antenna with a common port. The methods are located on the same physical surface. The present invention uses multiple decoupling methods at the same time to improve the isolation between antenna units:

1. In the low-frequency antenna unit 100, the low-frequency receiving antenna 110 is a circularly polarized antenna and is connected to a filter component 120, so that the overall low-frequency antenna unit 100 has its own filtering characteristics. By cascading the low-frequency receiving antenna 110 with filter components, the inter-frequency isolation is improved without increasing the height/thickness of the antenna;

2. In the low-frequency receiving antenna 110, by changing the outer contour shape of its radiator 111 to a uniform zigzag shape, the high-frequency isolation of the low-frequency receiving antenna is further improved;

3. In the high-frequency antenna unit 200, the high-frequency transmitting antenna 210 is a circularly polarized antenna, which is surrounded by a coupling-piece isolation wall 220. The coupling-piece isolation wall 220 improves the low-frequency isolation of the high-frequency transmission antenna 210. .

In this embodiment, without increasing the cross-section height of the co-oral antenna, the outer contour shape of the radiator of the receiving antenna is cleverly designed, and the antenna isolation is improved by adding filter components and isolation walls to each antenna unit. degree, which effectively solves the problems of poor isolation and mutual interference caused by the close distance between high and low frequency antenna units in co-oral phased array antennas. It also has the characteristics of very low profile and stable circular polarization in dual frequency bands.

Obviously, the above-mentioned embodiments of the present invention are only examples to clearly illustrate the technical solution of the present invention, and are not intended to limit the specific implementation of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the claims of the present invention shall be included in the protection scope of the claims of the present invention.

Claims (9)

1. A low-profile, high-isolation receiving and transmitting co-oral plane dual-frequency phased array antenna, which is characterized in that it consists of several low-frequency antenna units and high-frequency antenna units arranged in a cross arrangement; The low-frequency antenna unit includes a connected low-frequency receiving antenna and a filter component; The low-frequency receiving antenna is a microstrip antenna, including at least a radiator and a feeder, and the outer contour shape of the radiator is a sawtooth shape; The high-frequency antenna unit includes a high-frequency transmitting antenna and a coupling-piece isolation wall; the high-frequency antenna unit and the low-frequency antenna unit are isolated by a coupling-piece isolation wall. 2. The low-profile and high-isolation receiving and transmitting co-oral planar dual-frequency phased array antenna according to claim 1, characterized in that, in the high-frequency antenna unit, the isolation wall with coupling plates surrounds all The high-frequency transmitting antenna. 3. The low-profile and high-isolation receiving and transmitting co-oral plane dual-frequency phased array antenna according to claim 1, characterized in that the filter component is provided between the low-frequency receiving antenna and the high-frequency antenna unit. space, below the low-frequency receiving antenna, or on the back of the low-frequency receiving antenna. 4. The low-profile and high-isolation receiving and transmitting common-port dual-frequency phased array antenna according to claim 3, characterized in that the filtering component is a band-stop filter with 1/4 wavelength open-circuit branches. 5. The low-profile and high-isolation receiving and transmitting co-portal dual-frequency phased array antenna according to claim 4, characterized in that, in the low-frequency antenna unit, the band-rejection filter passes through a transition structure Connected to the low-frequency receiving antenna, the transition structure is used to convert the strip line of the band stop filter into a microstrip line. 6. The low-profile high-isolation receiving and transmitting co-oral planar dual-frequency phased array antenna according to claim 1, characterized in that the low-frequency antenna units are arranged in vertical and horizontal directions. 7. The low-profile and high-isolation receiving and transmitting common-port dual-frequency phased array antenna according to claim 6, characterized in that the low-frequency antenna units are separated by 0.4 to 0.6 wavelengths. 8. The low-profile and high-isolation receiving and transmitting co-oral planar dual-frequency phased array antenna according to claim 1, characterized in that the high-frequency antenna units are arranged along a ±45° direction. 9. The low-profile and high-isolation receiving and transmitting common-port dual-frequency phased array antenna according to claim 8, characterized in that the high-frequency antenna units are separated by 0.4 to 0.6 wavelengths.