A broadband dual circular polarization simultaneous same-frequency transmitting and receiving antenna array structure and antenna

Abstract

The present invention proposes a broadband dual-circular polarization simultaneous same-frequency transmitting and receiving antenna array structure and antenna, which relates to the technical field of microwave radio frequency antenna design. By designing the antenna array structure, polarization direction and feeding phase, the coupled signals of some sub-antennas cancel each other out, thereby obtaining higher transmit and receive isolation. At the same time, the antenna array structure operates in a dual-circular polarization mode for transmitting and receiving, which can adapt to the integrated communication fields of radar, remote sensing detection, and communication perception. The antenna finally proposed adds an artificial decoupling electromagnetic structure and a decoupling network corresponding to the residual H-plane and E-plane coupling modes of the antenna, ultimately achieving a relative isolation bandwidth of more than 20%, while maintaining a high antenna gain, which is conducive to adapting to the needs of the next generation of communication systems. At the same time, the antenna of the present invention does not require the use of additional duplexers or circulators, reducing the complexity of the communication system while improving the integration.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave radio frequency antenna design, and more specifically, to a broadband dual-circular polarization simultaneous same-frequency transmitting and receiving antenna array structure and antenna. Background Art

[0002] Traditional 3G and 4G communication systems are no longer able to meet the growing demand for wireless communications, making 5G and next-generation mobile communication technologies a hot topic of research. 5G and next-generation communication technologies urgently need to address issues such as spectrum resource shortages and high transmission latency. Simultaneous transmission and reception on the same frequency is considered one of the most promising technologies to overcome these challenges.

[0003] Simultaneous transmission and reception (SNR) is a bidirectional communication technology that simultaneously transmits and receives signals within the same frequency band. Theoretically, it doubles the throughput of traditional half-duplex systems, effectively utilizing spectrum resources. SNR also allows for the allocation of uplink and downlink transmission resources on different frequencies within certain time slots. This reduces uplink and downlink latency by allocating more uplink and downlink time slots. Furthermore, the flexible allocation of more uplink resources helps enhance uplink coverage and capacity. Given its capabilities, SNR is considered a key technology for 5G and next-generation communication systems. Furthermore, integrated communication and perception is a newly proposed technology for 5G and next-generation communication systems. It combines high-frequency beamforming with multiple antennas to enable base stations to perform radar-like functions, identifying the location, speed, and direction of vehicles and low-flying objects. Compared to radar, base stations with SNR offer significant advantages in coverage, range resolution, and angular measurement accuracy. SNR is a key technology for achieving SNR integration.

[0004] However, in co-frequency simultaneous transmission and reception systems, the transmitted signal can generate significant self-interference at the receiver. When the received signal is weak and the self-interference is strong, the self-interference signal not only overwhelms the target receive signal but can also directly saturate the receive link. Therefore, the greatest challenge in full-duplex communication technology is ensuring high isolation between the transmitter and receiver. Generally speaking, isolation technology for full-duplex communication systems can be implemented in the propagation domain (antenna domain), the RF domain, and the digital domain. Achieving high transmit-receive isolation at the antenna end addresses the problem of coupled transmit and receive signals in the system, and is also the most promising high-isolation technology solution. Furthermore, achieving high isolation at the antenna end is a necessary technical capability for co-frequency simultaneous transmission and reception systems. If the antenna isolation is insufficient, the self-interference signal received by the receiver will exceed the receiver's dynamic range. This will cause the target receive signal of interest to be submerged in the transmit signal, making it impossible to extract the received signal and further preventing self-interference cancellation in the RF and digital domains. In summary, research on co-frequency simultaneous transmission and reception antennas is of great value in improving the performance of full-duplex communication systems.

[0005] The traditional dual circular polarization co-frequency simultaneous transmission and reception antenna array structure realized by sequential rotational symmetric array is as follows: Figure 1 As shown, many solutions have been proposed domestically and internationally to improve the isolation of dual circularly polarized, co-frequency, simultaneous transmit and receive antennas, such as incorporating artificial electromagnetic structures, utilizing defect-ground technology, and adding high-impedance surfaces. However, the 40dB isolation achieved by these solutions is less than 7% of the relative bandwidth. The prior art discloses an E-band miniaturized flat-panel antenna and a co-frequency duplexer comprising the same antenna. This E-band miniaturized flat-panel antenna features four equally spaced, rectangularly arranged small radiating elements mounted on a large radiating element, which is connected to a feed waveguide via a coupling slot. Two E-band miniaturized flat-panel antennas, serving as the transmitting and receiving antennas, are integrated in parallel within the co-frequency duplexer, with orthogonal polarizations. This antenna utilizes miniaturized flat-panel antennas, making it easy to integrate without increasing system complexity. Furthermore, the duplex system improves system integration and reduces system complexity, effectively enhancing spectrum resource utilization. However, the transmit and receive polarizations of this antenna are orthogonal, resulting in naturally high isolation. However, in applications such as radar and integrated communications and remote sensing, non-orthogonal transmit and receive polarizations are required. Summary of the Invention

[0006] To address the problem that the polarization mode of simultaneous co-frequency transmitting and receiving antennas cannot match technologies such as radar and integrated communication and remote sensing, the present invention proposes a broadband dual-circular polarization simultaneous co-frequency transmitting and receiving antenna array structure and antenna with high isolation bandwidth and high gain, which can be applied to full-duplex communication systems, integrated communication and sensing technologies, and low-latency communication technologies.

[0007] In order to achieve the above technical effects, the technical solutions of the present invention are as follows:

[0008] A broadband dual-circular polarization simultaneous co-frequency transmitting and receiving antenna array structure includes four antenna units of the same size, the four antenna units are respectively located in four quadrants of a rectangular coordinate system, and the adjacent antenna units on the left and right are symmetrical about the y-axis;

[0009] Each antenna unit is provided with a feeding structure with a vertical feeding direction, namely a transmitting end feeding structure and a receiving end feeding structure; the linear polarization directions generated by the transmitting end feeding structure on the four antenna units are mutually orthogonal and have a phase difference of 90°, synthesizing circular polarization; the linear polarization directions generated by the receiving end feeding structure on the four antenna units are mutually orthogonal and have a phase difference of 90°, synthesizing circular polarization, and the four antenna units synthesize dual circular polarization for transmission and reception.

[0010] Preferably, the polarization direction of the transmitting end feeding structure of the antenna unit located in the first quadrant and the transmitting end feeding structure of the antenna unit located in the second quadrant are both in the y-axis direction, and the feeding direction and phase of the two transmitting end feeding structures are the same; the polarization direction of the transmitting end feeding structure of the antenna unit located in the third quadrant and the transmitting end feeding structure of the antenna unit located in the fourth quadrant are both in the x-axis direction, but the feeding direction and phase of the two transmitting end feeding structures are opposite, and the linear polarizations orthogonal to each other in the y-axis direction and the x-axis direction are combined into circular polarization. The circular polarization type of the transmitting end is inconsistent with the circular polarization type of the receiving end.

[0011] Preferably, the polarization direction of the receiving-end feeding structure of the antenna unit located in the first quadrant and the receiving-end feeding structure of the antenna unit located in the second quadrant are both in the x-axis direction, and the feeding directions and phases of the two receiving-end feeding structures are opposite; the polarization direction of the receiving-end feeding structure of the antenna unit located in the third quadrant and the receiving-end feeding structure of the antenna unit located in the fourth quadrant are both in the y-axis direction, but the feeding directions and phases of the two receiving-end feeding structures are the same, and the linear polarizations orthogonal to each other in the y-axis direction and the x-axis direction are combined into circular polarization. The circular polarization type of the receiving end is inconsistent with the circular polarization type of the transmitting end.

[0012] Preferably, the antenna array structure further includes a feeding network, and both the transmitting-end feeding structure and the receiving-end feeding structure are connected to an output port of the feeding network.

[0013] The present invention also proposes a broadband dual circularly polarized simultaneous co-frequency transmitting and receiving antenna, which is implemented based on the antenna array structure. The antenna unit can be in the form of a common antenna such as a patch antenna, a horn antenna, or a dipole antenna.

[0014] Preferably, the antenna includes four antenna units of the same size, a transmitting feed network, and a receiving feed network. Each feed network has four output ports, which are respectively connected to the antenna units adjacent to each other in the four quadrants.

[0015] Preferably, the transmitting feed network and the receiving feed network are both composed of a transmission line, a power divider and a phase shifter; the power divider evenly distributes the energy of the input port of each feed network to the four output ports, and the phase shifter provides the four antenna units with the feeding phase in the antenna unit as described in claim 2 or 3, and the input port, power divider, phase shifter and output port of the feed network are connected by a transmission line.

[0016] Preferably, the antenna also includes: an artificial decoupling electromagnetic structure, which can be regarded as a high-impedance electromagnetic structure within a specific frequency range, hindering the propagation of electromagnetic waves within the specific frequency range; the resonant mode of the artificial decoupling electromagnetic structure cooperates with the H-plane coupling mode of the antenna to achieve high isolation between sub-antenna units within the working frequency band.

[0017] In the above technical solution, based on the working principle of the LC band-stop filter, the artificial decoupling electromagnetic structure responds to the H-plane coupling mode generated by the parallel polarization between the two antenna units to deal with the residual H-plane coupling mode and reduce the propagation of the H-plane mode coupled electromagnetic waves. It can prevent the transmission of electromagnetic waves within a specific frequency range and reduce the coupling between antennas placed along the H-plane of the antenna unit, ultimately realizing dual circularly polarized simultaneous transmission and reception with a wide frequency band and high transmission and reception isolation.

[0018] Preferably, the antenna further comprises a decoupling network, which is composed of a transmission line and a coupler, wherein the coupler is connected to the antenna unit placed along the E-plane of the antenna unit.

[0019] Preferably, two couplers are connected by a transmission line to form a cancellation signal with high linearity and a size similar to that of the residual E-plane coupling mode. The length of the transmission line connecting the couplers is changed so that the phase of the cancellation signal is opposite to the phase of the antenna coupling signal, ultimately achieving wide-band decoupling.

[0020] In the above technical solution, a reverse high-linearity cancellation signal is formed through a decoupling network to deal with the residual E-plane coupling mode, thereby achieving wide-band decoupling.

[0021] Compared with the prior art, the beneficial effects of the technical solution of the present invention are:

[0022] The present invention proposes a broadband dual-circular polarization simultaneous co-frequency transmitting and receiving antenna array structure and antenna. By designing the antenna array structure, polarization direction, and feeding phase, the coupled signals of some sub-antennas cancel each other out, thereby achieving higher transmit-receive isolation. At the same time, the antenna array structure operates in a dual-circular polarization transmitting and receiving mode, which can adapt to the integrated communication fields of radar, remote sensing detection, and communication perception. The antenna finally proposed adds an artificial decoupling electromagnetic structure and a decoupling network corresponding to the residual H-plane and E-plane coupling modes of the antenna, ultimately achieving a relative isolation bandwidth of more than 20%, while maintaining a high antenna gain, which is conducive to adapting to the needs of the next generation of communication systems. At the same time, the antenna of the present invention does not require the use of additional duplexers or circulators, reducing the complexity of the communication system while improving the integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of a conventional dual circularly polarized, co-frequency, simultaneous transmitting and receiving antenna array implemented by a sequential rotationally symmetric array proposed in the background art of the present invention is shown;

[0024] Figure 2 Schematic diagram showing the structure of a dual circularly polarized, co-frequency, simultaneous transmitting and receiving antenna array proposed in Example 1 of the present invention;

[0025] Figure 3 A schematic diagram showing the specific structure of the antenna unit proposed in Embodiment 2 of the present invention;

[0026] Figure 4 A diagram showing the S-parameter simulation results of the antenna unit proposed in Example 2 of the present invention;

[0027] Figure 5 A structural diagram showing a broadband dual circularly polarized simultaneous co-frequency transmitting and receiving antenna proposed in Example 3 of the present invention;

[0028] Figure 6 Schematic diagram of the artificial electromagnetic three-dimensional structure proposed in Example 3 of the present invention;

[0029] Figure 7 A schematic diagram showing the decoupling effect of adding an artificial electromagnetic structure proposed in Example 3 of the present invention;

[0030] Figure 8 An S-parameter simulation diagram showing the complete antenna structure proposed in Example 3 of the present invention;

[0031] Figure 9 : represents the receiving pattern of the complete antenna structure proposed in Example 3 of the present invention at 4.5 GHz;

[0032] Figure 10 : represents the receiving pattern of the complete antenna structure proposed in Example 3 of the present invention at 5 GHz;

[0033] Figure 11 : represents the receiving pattern of the complete antenna structure proposed in Example 3 of the present invention at 5.5 GHz;

[0034] Figure 12 : represents the transmission pattern of the complete antenna structure proposed in Example 3 of the present invention at 4.5 GHz;

[0035] Figure 13 : represents the transmission pattern of the complete antenna structure proposed in Example 3 of the present invention at 5 GHz;

[0036] Figure 14 : represents the transmission pattern of the complete antenna structure proposed in Example 3 of the present invention at 5.5 GHz;

[0037] Figure 15 1 shows the receiving gain diagram of the antenna proposed in embodiment 3 of the present invention;

[0038] Figure 16 : represents the transmission gain diagram of the antenna proposed in embodiment 3 of the present invention;

[0039] Figure 17 A diagram showing the receiving axial ratio of the antenna proposed in Example 3 of the present invention;

[0040] Figure 18 A diagram showing the transmission axis ratio of the antenna proposed in embodiment 3 of the present invention. DETAILED DESCRIPTION

[0041] The accompanying drawings are for illustrative purposes only and are not to be construed as limiting this patent;

[0042] In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged, or reduced, and do not represent the actual size;

[0043] It is understandable to those skilled in the art that descriptions of certain well-known contents may be omitted in the drawings.

[0044] The technical solution of the present invention is further described below with reference to the accompanying drawings and embodiments.

[0045] The positional relationships described in the drawings are for illustrative purposes only and should not be construed as limiting this patent;

[0046] Example 1

[0047] like Figure 2 As shown, this embodiment proposes a broadband dual circularly polarized simultaneous co-frequency transmit and receive antenna array structure, including four antenna units of the same size. The antenna type of each unit is a patch-type metasurface antenna. The four antenna units are respectively located in four quadrants of a rectangular coordinate system, and the adjacent antenna units on the left and right are symmetrical about the y-axis.

[0048] In this embodiment, each antenna unit is represented by a rectangle, and each antenna unit is provided with a feeding structure with a vertical feeding direction (see Figure 2 The phase of the feeding structure is marked next to the arrow, with 0°, 90°, and 180°, which are the transmitting end feeding structure and the receiving end feeding structure respectively; the linear polarization directions generated by the transmitting end feeding structure on the four antenna units are orthogonal to each other and have a phase difference of 90°, synthesizing circular polarization; the linear polarization directions generated by the receiving end feeding structure on the four antenna units are orthogonal to each other and have a phase difference of 90°, synthesizing circular polarization, and the four antenna units synthesize transmitting and receiving dual circular polarization.

[0049] For details, see Figure 2 The polarization directions of the transmitting end feeding structure of the antenna unit located in the first quadrant and the transmitting end feeding structure of the antenna unit located in the second quadrant are both in the y-axis direction. Figure 2 The "solid line" in the middle represents the transmitting end feeding structure, corresponding to transmitting port 3 and transmitting port 4. The feeding direction and phase of the two transmitting end feeding structures are the same, and both generate radiation fields in the y-axis direction; the polarization direction of the transmitting end feeding structure of the antenna unit located in the third quadrant and the transmitting end feeding structure of the antenna unit located in the fourth quadrant are both in the x-axis direction, corresponding to Figure 2 The transmitting port 1 and transmitting port 2 are shown in the figure, but the feeding directions and phases of the two transmitting end feeding structures are opposite (the feeding phase of the transmitting feeding structure corresponding to transmitting port 1 is 0°, and the feeding phase of the transmitting feeding structure corresponding to transmitting port 2 is 180°), and the linear polarizations in the y-axis direction and the x-axis direction are orthogonal to each other and are synthesized into circular polarization.

[0050] The analysis of the receiving end feeding structure is similar. The polarization direction of the receiving end feeding structure of the antenna unit located in the first quadrant and the receiving end feeding structure of the antenna unit located in the second quadrant are both in the x-axis direction. The feeding directions and phases of the two receiving end feeding structures are opposite (such as Figure 2 As shown, the feeding phases of the two receiving-end feeding structures are 180° and 0° respectively); the polarization directions of the receiving-end feeding structure of the antenna unit located in the third quadrant and the receiving-end feeding structure of the antenna unit located in the fourth quadrant are both in the y-axis direction, but the feeding directions and phases of the two receiving-end feeding structures are the same (both 90°), and the linear polarizations orthogonal to each other in the y-axis direction and the x-axis direction are combined into circular polarization. In actual implementation, by setting the feeding phase and polarization direction of each sub-port, the working mode of the antenna array structure is dual circular polarization for transmission and reception. The symmetry of the array makes the coupling signals of some sub-antennas equal, specifically C51=C62, C61=C52, C73=C84, C83=C74, where CXY represents the coupling from the transmitting port Y to the receiving port X. These two types of coupling cancel each other out at the feeding network due to the 180° difference in feeding phases.

[0051] Example 2

[0052] The antenna array structure proposed in this embodiment also includes a feed network, and the transmitting end feed structure and the receiving end feed structure are both connected to the output port of the feed network. The antenna array structure proposed in this embodiment is described below with a specific example. Figure 3 Each antenna unit includes a top layer, a middle layer, and a bottom layer. In this embodiment, the top layer is a metasurface antenna 1, which is composed of sixteen rectangles of the same size, forming a 4*4 equally spaced rectangular array. The middle layer is a mutually perpendicular L-shaped feeding structure 2, corresponding to the transmitting feeding structure and the receiving feeding structure respectively. The L-shaped feeding structure is composed of metal vias and metal rectangles. A number of microstrip lines 3 are provided on the bottom layer. The microstrip lines are used as the feeding network. The metal rectangles are connected to one end of the microstrip lines of the bottom layer through metal vias. In this embodiment, there are two microstrip lines. The antenna medium and the feeding network medium are filled between the top layer, the middle layer, and the bottom layer. The S parameter simulation results of the antenna unit are shown as follows. Figure 4 As shown in the figure, its impedance bandwidth is 4.6GHz-6GHz, and the relative impedance bandwidth is 26%. The metasurface antenna unit has the advantages of low profile, broadband and high gain.

[0053] Example 3

[0054] This embodiment proposes a broadband dual circularly polarized simultaneous frequency transmitting and receiving antenna, which is implemented based on the antenna array structure. In specific implementation, the antenna unit can be in the form of a patch antenna, a horn antenna, a dipole antenna or other common antenna forms. In this embodiment, the antenna includes four antenna units of the same size, a transmitting feed network, and a receiving feed network. Each feed network has four output ports, which are respectively connected to the upper and lower adjacent and left and right adjacent antenna units in the four quadrants; the transmitting feed network and the receiving feed network are composed of transmission lines, power dividers and phase shifters; the power divider evenly distributes the energy of the input port of each feed network to the four output ports, and the phase shifter provides the four antenna units with the feeding phase in the antenna unit as described in claim 2 or 3. The input port, power divider, phase shifter and output port of the feed network are connected by a transmission line. Figure 3 As an example, the antenna unit formed by the structure shown in FIG. Figure 5The antenna includes four antenna units 101 of the same size, a microstrip power divider 102, and a microstrip bridge 103. The microstrip power divider 102 connects the vertically adjacent and the horizontally adjacent antenna units, and together with the microstrip bridge 103, forms a power-splitting phase-shifted feeding network. In this embodiment, according to the basic theory of microwave engineering, the longer the physical length of the transmission line, the greater the corresponding transmission phase delay. The final antenna design has a total size of 166mm x 166mm x 3.758mm. Its impedance bandwidth is 4.6GHz-6.5GHz, the 40dB isolation bandwidth is 4.8GHz-6GHz, and the relative isolation bandwidth is 22.2%.

[0055] In this embodiment, the antenna further includes: an artificial decoupling electromagnetic structure 4, which can be regarded as a high-impedance electromagnetic structure within a specific frequency range, hindering the propagation of electromagnetic waves within the specific frequency range; the resonant mode of the artificial decoupling electromagnetic structure cooperates with the H-plane coupling mode of the antenna to achieve high isolation between the sub-antenna units within the working frequency band. In this embodiment, see Figure 5 The artificial decoupling electromagnetic structure 4 is set between two adjacent antenna units symmetrically along the y-axis. The artificial decoupling electromagnetic structure 4 is composed of a metal patch 41 and a grounding cylinder 42. The size of the metal patch determines the capacitance value of the artificial decoupling electromagnetic structure 4, and the distance between the grounding cylinders determines the inductance value of the artificial decoupling electromagnetic structure 4. Ultimately, the response is in the 4.9 GHz frequency band. Figure 5 In order to minimize the propagation of H-plane mode coupled electromagnetic waves, a total of 4*2 artificial decoupling electromagnetic structure arrays are placed in this embodiment. The length of the artificial decoupling electromagnetic structure 4 array is the same as the width of the antenna unit, and the resonant mode of the artificial decoupling electromagnetic structure 4 cooperates with the H-plane coupling mode of the antenna.

[0056] In the above technical solution, the artificial decoupling electromagnetic structure responds to the H-plane coupling mode between the two antenna units, reducing the propagation of the H-plane coupled electromagnetic waves. This can prevent the transmission of electromagnetic waves within a specific frequency range and reduce the coupling between antennas placed along the H-plane of the antenna unit, ultimately achieving dual circularly polarized simultaneous transmission and reception at the same frequency with a wide frequency band and high transmission and reception isolation.

[0057] The antenna also includes a decoupling network, which is composed of a transmission line and a coupler 104. The coupler 104 is connected in parallel to the antenna unit placed along the E-plane of the antenna unit. The two couplers 104 are connected by a transmission line to form a cancellation signal with high linearity and a size similar to the residual E-plane coupling mode. By changing the length of the transmission line connecting the couplers 104, the phase of the cancellation signal is opposite to the phase of the antenna coupling signal, ultimately achieving broadband decoupling. Figure 7As shown, after the antenna proposed by this invention incorporates an artificial decoupling electromagnetic structure, the coupling of the sub-antennas placed along the antenna's H-plane remains less than -38dB across the entire frequency band, significantly improving isolation compared to the antenna without the artificial decoupling electromagnetic structure. By incorporating the artificial electromagnetic structure, 40dB of isolation was ultimately achieved within the 4.8-6GHz bandwidth.

[0058] In the above technical solution, a reverse high-linearity cancellation signal is formed through a decoupling network to deal with the residual E-plane coupling mode, thereby achieving wide-band decoupling.

[0059] Figure 8 Simulation diagram showing the S-parameters of the complete antenna structure; Figures 9 to 11 Respectively represent the receiving radiation patterns of the complete antenna structure at 4.5GHz, 5GHz, and 5.5GHz, Figures 12 to 14 Respectively represent the transmission patterns of the complete antenna structure at 4.5GHz, 5GHz, and 5.5GHz; Figure 15 and Figure 16 They represent the receiving gain diagram and transmitting gain diagram of the antenna respectively. When receiving, the maximum gain is 11.4dBi, and the 3dB gain bandwidth is 4.56GHz-6.26GHz. When transmitting, the maximum gain is 11.8dBi, and the 3dB gain bandwidth is 4.6GHz-6.26GHz. Figure 17 and Figure 18 The figures respectively represent the receiving axial ratio diagram and transmitting axial ratio diagram of the antenna. When receiving, the 3dB axial ratio bandwidth is 4.07GHz-6.56GHz; when transmitting, the 3dB axial ratio bandwidth is 4.05GHz-6.65GHz.

[0060] In general, by designing the antenna array structure and adding artificial decoupling electromagnetic structure and decoupling network to deal with the residual H-plane and E-plane coupling modes respectively, the self-decoupling technology theory and method in the dual circularly polarized antenna are formed, and finally the dual circularly polarized co-frequency simultaneous transmission and reception antenna technology and solution with wide frequency band and high transmission and reception isolation is realized.

[0061] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A broadband dual circular polarization simultaneous same-frequency transmitting and receiving antenna array structure, characterized in that: It includes four antenna units of the same size, the four antenna units are respectively located in four quadrants of a rectangular coordinate system, and the left and right adjacent antenna units are symmetrical about the y-axis; Each antenna unit is provided with a feeding structure with a vertical feeding direction, which is a transmitting end feeding structure and a receiving end feeding structure respectively; The linear polarization directions generated by the transmitting end feeding structure on the four antenna units are orthogonal to each other and have a phase difference of 90°, synthesizing circular polarization; the linear polarization directions generated by the receiving end feeding structure on the four antenna units are orthogonal to each other and have a phase difference of 90°, synthesizing circular polarization. The four antenna units synthesize dual circular polarization for transmission and reception.

2. The broadband dual circularly polarized simultaneous co-frequency transmitting and receiving antenna array structure according to claim 1, characterized in that: The polarization directions of the transmitting end feeding structure of the antenna unit located in the first quadrant and the transmitting end feeding structure of the antenna unit located in the second quadrant are both in the y-axis direction, and the feeding directions and phases of the two transmitting end feeding structures are the same; the polarization directions of the transmitting end feeding structure of the antenna unit located in the third quadrant and the transmitting end feeding structure of the antenna unit located in the fourth quadrant are both in the x-axis direction, but the feeding directions and phases of the two transmitting end feeding structures are opposite, and the linear polarizations orthogonal to each other in the y-axis direction and the x-axis direction are combined into circular polarization, and the circular polarization type of the transmitting end is inconsistent with the circular polarization type of the receiving end.

3. The broadband dual circularly polarized simultaneous co-frequency transmitting and receiving antenna array structure according to claim 1, characterized in that: The polarization directions of the receiving-end feeding structure of the antenna unit located in the first quadrant and the receiving-end feeding structure of the antenna unit located in the second quadrant are both in the x-axis direction, and the feeding directions and phases of the two receiving-end feeding structures are opposite; the polarization directions of the receiving-end feeding structure of the antenna unit located in the third quadrant and the receiving-end feeding structure of the antenna unit located in the fourth quadrant are both in the y-axis direction, but the feeding directions and phases of the two receiving-end feeding structures are the same, and the linear polarizations orthogonal to each other in the y-axis direction and the x-axis direction are combined into circular polarization, and the circular polarization type of the receiving end is inconsistent with the circular polarization type of the transmitting end.

4. The broadband dual circularly polarized simultaneous co-frequency transmitting and receiving antenna array structure according to any one of claims 1 to 3, characterized in that: The antenna array structure further includes a feeding network, and both the transmitting end feeding structure and the receiving end feeding structure are connected to the output port of the feeding network.

5. A broadband dual circular polarization simultaneous same-frequency transmitting and receiving antenna, characterized in that: The antenna is implemented based on the antenna array structure according to any one of claims 1 to 3.

6. The broadband dual circularly polarized simultaneous co-frequency transmitting and receiving antenna according to claim 5, characterized in that: The antenna includes four antenna units of the same size, a transmitting feed network, and a receiving feed network. Each feed network has four output ports, which are respectively connected to the antenna units adjacent to each other in the four quadrants.

7. The broadband dual circularly polarized simultaneous co-frequency transmitting and receiving antenna according to claim 6, characterized in that: Both the transmitting feed network and the receiving feed network are composed of transmission lines, power dividers and phase shifters; the power divider evenly distributes the energy of the input port of each feed network to the four output ports, and the phase shifter provides the four antenna units with the feeding phase of the transmitting end or receiving end feeding structure in the broadband dual circularly polarized simultaneous co-frequency transceiver antenna array structure as described in claim 2 or 3. The input port, power divider, phase shifter and output port of the feed network are connected by transmission lines.

8. The broadband dual circularly polarized simultaneous co-frequency transmitting and receiving antenna according to claim 7, characterized in that: The antenna also includes: an artificial decoupling electromagnetic structure, which can be regarded as a high-impedance electromagnetic structure within a specific frequency range, hindering the propagation of electromagnetic waves within the specific frequency range; the resonant mode of the artificial decoupling electromagnetic structure cooperates with the H-plane coupling mode of the antenna to achieve high isolation between sub-antenna units within the working frequency band.

9. The broadband dual circularly polarized simultaneous co-frequency transmitting and receiving antenna according to claim 7, characterized in that: The antenna further includes a decoupling network, which is composed of a transmission line and a coupler, wherein the coupler is connected to the antenna unit placed along the E surface of the antenna.

10. The broadband dual circularly polarized simultaneous co-frequency transmitting and receiving antenna according to claim 9, characterized in that: Two couplers are connected by a transmission line to form a cancellation signal with high linearity and the same amplitude as the residual E-plane coupling. By changing the length of the transmission line connecting the couplers, the phase of the cancellation signal is opposite to the phase of the antenna coupling signal, ultimately achieving wide-band decoupling.

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