Easy-feed broadband dual-polarized reconfigurable transmission antenna array

Abstract

This invention relates to the field of dual-polarized antenna manufacturing technology, specifically to an easily fed broadband dual-polarized reconfigurable transmission antenna array, comprising: a feed antenna, a DC bias network, and two or more dual-polarized reconfigurable elements. Each dual-polarized reconfigurable transmission antenna element is formed by two identical reconfigurable transmission elements orthogonally arranged on the same plane. Each reconfigurable transmission element contains two linearly polarized dipoles arranged in the same direction, forming a receiving and transmitting structure consisting of an active receiving dipole and a passive asymmetric transmitting dipole. The two dipoles are separated by a common ground point and connected by a metallized via. A dipole is connected in parallel next to each dipole element as a passive parasitic bypass to extend the antenna bandwidth. The receiving dipole integrates two pin diodes.

Description

Technical fields:

[0001] This invention relates to the field of dual-polarized antenna manufacturing technology, specifically to an easily fed broadband dual-polarized reconfigurable transmission antenna array. Background technology:

[0002] Antennas serve as the terminals of microwave systems. By converting microwave signals into electromagnetic waves that propagate in free space, they enable wireless communication, acting as the hub between the microwave system and free space. Furthermore, with the continuous development of communication systems, the demands on antenna performance are increasing. To meet the stringent requirements of long-distance communication, radar detection, microwave landing, and electronic jamming countermeasures, antennas with strong directivity and high gain, possessing advantages such as multi-polarization, low profile, and electrically controllable beam scanning, are needed to compensate for spatial attenuation issues. Phased array antennas offer advantages such as rapid switching of beam scanning direction and beam shape, high gain, low profile, and ease of fabrication. However, the phase-shifting structure of most phased array antennas uses phase shifter chips to independently control the phase change of each element. Phase shifter chips are expensive, require complex feeding networks, and suffer from varying degrees of insertion loss, leading to increased antenna loss and reduced efficiency.

[0003] Reconfigurable array antennas alter the transmission phase by loading active devices such as MEMS, varactors, and PIN diodes onto traditional elements. By controlling the states of these active devices, the current distribution and direction of the electromagnetic radiator are changed, thus altering its transmission phase. This technology has wide applications in antenna design, such as superlenses, radar radomes, and polarization conversion. Through specific phase design of the elements, high-gain radiation beams can be obtained while simultaneously achieving electronically controlled array beam scanning. It offers advantages such as simple structure, low manufacturing cost and process requirements, no complex feed network, and easy integration with microstrip circuits.

[0004] Existing research shows that using diodes to control metasurfaces has advantages over other control methods, such as simple point-by-point control and lower production and control costs. However, most reconfigurable metasurface antennas are currently single-polarized, while dual-polarized reconfigurable metasurface solutions have limitations, such as being able to control only one row or column of elements, not being able to encode any individual element, and lacking a choke structure in the DC feed network, which can easily affect the DC signal. Summary of the Invention:

[0005] This invention addresses the shortcomings and deficiencies of existing technologies by proposing an easily fed broadband dual-polarized reconfigurable transmission antenna array.

[0006] This invention achieves its purpose through the following measures:

[0007] A broadband dual-polarized reconfigurable transmission antenna array that is easily fed is characterized by comprising: a feed antenna, a DC bias network, and two or more dual-polarized reconfigurable units. Each dual-polarized reconfigurable transmission antenna unit is formed by two identical reconfigurable transmission units orthogonally arranged on the same plane. Each reconfigurable transmission unit contains two linearly polarized dipoles arranged in the same direction. The two dipoles form a receiving and transmitting structure consisting of an active receiving dipole and a passive asymmetric transmitting dipole. The two dipoles are separated by a common ground point and connected by a metallized through-hole. A 7±0.5mm dipole is connected in parallel next to each dipole unit as a passive parasitic bypass to extend the antenna bandwidth. The receiving dipole integrates two pin diodes to control the on / off state of the antenna unit pin diodes based on the current reversal principle to achieve 1-bit encoding.

[0008] The DC bias network consists of DC feeds corresponding to each dual-polarization reconfigurable unit. The DC feeds are narrow microstrip lines. Each dual-polarization reconfigurable unit has two independent DC feeds, each corresponding to a polarization. For each receiver-transmitter structure, the middle part of the active receiver dipole is grounded through the passive transmitter dipole. The two ends of the active receiver dipole are given a +1.3 / -1.3V DC bias voltage through the DC feeds to control the diode state. The DC feeds have a quarter-wavelength fan-shaped stub with an open circuit at the end for filtering, rectification, and RF suppression.

[0009] The feed antenna uses a corrugated horn antenna as the feed source. The corrugated horn antenna is placed above the center of the reconfigurable transmission array as the feed source. The unit is encoded according to the phase distribution required for different beam pointing angles to perform phase compensation and achieve the effect of electronically controlled beam scanning.

[0010] In this invention, the dual-polarization reconfigurable unit needs to be designed in a slender shape to meet the dual-polarization requirement, facilitating the subsequent orthogonal arrangement of two identical unit structures. Each dual-polarization reconfigurable unit consists of an active receiving dipole and a passive transmitting dipole. A parasitic bypass is added next to the dipole. When the unit is working, the current of the receiving and transmitting dipoles couples to the parasitic bypass, forming a reverse current and generating a new resonance, greatly extending the operating band. A convex structure is used to connect the two ends of the dipole, facilitating the subsequent DC feed line design. Since the transmission unit integrates active devices, it is necessary to consider the unit structure... A corresponding bias circuit is set on the structure to apply a reverse bias voltage to the varactor diode. A connection layer is added between the active dipole dielectric substrate and the ground layer for DC bias routing. The routing line is a high-impedance microstrip line with a width of 0.2mm. A fan-shaped choke is added to the bias line. The stub length is usually a quarter wavelength, which can isolate DC signals. The choke characteristic is used to reduce the mutual interference between radio frequency signals and DC signals. Since the fan-shaped stub is also an open structure, it will also radiate. It should be placed near the electric field zero point to reduce its impact on the transmission performance of the entire unit.

[0011] In this invention, the receiving dipole integrates two pin diodes. Based on the current reversal principle, the on / off state of the transmission unit pin diodes is controlled to achieve 1-bit encoding. In order to obtain high performance and stable RTA component performance, the diode model selected is MADP-000907-14020. In the actual simulation, the pin diodes are modeled as lumped elements. The initial value of the pin diodes in the on state is equivalent to a cascade of R = 7.8Ω and L = 30pH, and the initial value in the off state is equivalent to a cascade of C = 0.025F and L = 30pH.

[0012] The feed antenna in this invention is composed of a circular waveguide corrugated horn antenna. The horn opening radius is 21.20 mm and the length is 25.26 mm. It has three annular choke slots inside. Compared with the traditional horn antenna, it has excellent performance in reducing edge diffraction, improving the symmetry of the lobe pattern and reducing cross polarization.

[0013] In this invention, to reduce the number of traces in the edge units, the bias network adopts a top-bottom symmetrical structure, ensuring that there are a maximum of 5 DC traces on each unit. The trace width is 0.2mm. On the same dielectric substrate, the narrower the trace, the higher the impedance to the radio frequency signal. Choosing a 0.2mm high-impedance trace can not only suppress the interference of the radio frequency signal to the DC signal, but also facilitate the layout of the traces. At the same time, in order to ensure that the DC signals between different units do not interfere with each other, the spacing between adjacent feed lines is also 0.2mm. In order to enable individual control of units with two polarization states and reduce cross polarization, the DC traces of the two polarization states are independent of each other.

[0014] In this invention, after the electromagnetic waves emitted by the fed horn reach the transmission array, the unequal spatial distances from the fed horn to each transmission element result in different spatial phase differences in the incident waves received by each transmission element. Based on the position of the phase center of the fed horn and the beam direction of the planar transmission array antenna, the phase delay of each transmission element on the incident wave is calculated. Then, the transmission elements are designed to perform appropriate phase compensation on the incident wave, thereby enabling the transmitted electromagnetic waves to superimpose in phase in the designed direction, forming an equiphase surface, ultimately obtaining the desired highly directional pencil beam. Before calculating the compensated phase, the focal length between the fed horn and the transmission array needs to be determined.

[0015] For traditional antennas, efficiency is crucial; higher efficiency means better performance and more radiated energy. For transmission arrays, the primary focus is on aperture efficiency, which can be calculated using the following formula:

[0016] η a =G m / G

[0017] G=4πD / λ 2 (1),

[0018] Where is the ideal gain of G, and G is the ideal gain. m Let F represent the measured gain of the array antenna, and D be the array aperture size. To achieve higher efficiency, selecting the optimal focal length (F) is crucial. For a given feed mode, there exists an optimal F / D value. The focal length for optimal aperture efficiency is F = 85mm, with a focal length-to-diameter ratio of F / D = 0.91. After determining the focal length, to obtain a high-gain plane wave in the desired direction, the phase of the RTA at (m, n) can be written as:

[0019]

[0020] m and n are the labels relative to the array elements, and p is the element period, which is 9.3 mm. The reference phase of the central element is α, and β are the beam scanning angles in the x and y directions, respectively. For continuous phase modulation, different... This does not affect the performance of phase compensation; however, for 1-bit phase quantization, only 0° and 180° phase states are provided, and the phase distribution in equation (2) can be defined as:

[0021]

[0022] After the phase is determined, the entire array is encoded. The antenna controls the transmission phase of each unit in two polarization directions by switching the PIN diode on the control unit, thereby realizing dual-polarized electronically controlled beam scanning.

[0023] Compared with the prior art, the present invention has significant advantages such as reasonable structure and reliable operation. Attached image description:

[0024] Appendix Figure 1 This is a schematic diagram of the structure of the present invention.

[0025] Appendix Figure 2 This is a schematic diagram of the reconfigurable transmission unit in this invention, wherein... Figure 2 (a) is a traditional unit structure diagram, (b) is a unit structure diagram with parasitic bypass added, and (c) is a unit structure diagram in an embodiment of the present invention.

[0026] Appendix Figure 3 This is a schematic diagram of the bias circuit structure of the reconfigurable transmission unit in this invention.

[0027] Appendix Figure 4 This is a schematic diagram of the layer structure of the reconfigurable transmission unit in this invention, wherein... Figure 4 (a) is a schematic diagram of the overall structure decomposition, (b) is a schematic diagram of the top-level structure, and (c) is a schematic diagram of the bottom-level structure.

[0028] Appendix Figure 5 This is a simulated S-parameter curve of the reconfigurable transmission unit in an embodiment of the present invention, wherein... Figure 5 In the figure, (a) is the curve of return loss versus transmission amplitude, and (b) is the curve of transmission phase.

[0029] Appendix Figure 6 This is a current distribution diagram of the reconfigurable transmission unit in an embodiment of the present invention. Figure 6 (a) is the x-polarization on current distribution diagram, (b) is the x-polarization off current distribution diagram, (c) is the y-polarization on current distribution diagram, and (d) is the y-polarization off current distribution diagram.

[0030] Appendix Figure 7 This is a diagram of the corrugated horn structure in an embodiment of the present invention, wherein... Figure 7 (a) is a side view of the structure, and (b) is a top view.

[0031] Appendix Figure 8 This is a return loss curve of the corrugated horn in an embodiment of the present invention.

[0032] Appendix Figure 9 This is the 16Hz directional pattern of the corrugated horn in this embodiment of the invention.

[0033] Appendix Figure 10 This is a diagram of the DC bias network structure in an embodiment of the present invention.

[0034] Appendix Figure 11 This is a gain-frequency curve diagram in an embodiment of the present invention.

[0035] Appendix Figure 12 This is an embodiment of the invention showing 16Hz encoding and 3D radiation pattern, wherein... Figure 12 (a) is a schematic diagram with a scanning angle of 0°, (b) is a schematic diagram with a scanning angle of -10°, (c) is a schematic diagram with a scanning angle of -20°, (d) is a schematic diagram with a scanning angle of -30°, (e) is a schematic diagram with a scanning angle of -40°, and (f) is a schematic diagram with a scanning angle of -50°.

[0036] Appendix Figure 13 This is a beam scanning curve at 16Hz in an embodiment of the present invention.

[0037] Appendix Figure 14 This is the principal plane radiation pattern in an embodiment of the present invention, wherein... Figure 14 (a) is plane E, and (b) is plane H.

[0038] Figure reference numerals: 1. Corrugated horn; 2. DC bias network; 3. Vertically polarized receiving dipole; 4. Horizontally polarized receiving dipole; 5. Receiver patch; 6. Bias circuit; 7. Connection layer; 8. Ground; 9. Transmitting patch. Detailed implementation method:

[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0040] Example:

[0041] This example proposes a dual-polarized reconfigurable transmission array antenna, which achieves the effect of electrically controlled beam scanning by loading active pin tubes. It consists of a corrugated horn feed antenna, dipoles operating in two mutually orthogonal polarization states, and a DC bias network.

[0042] In this example, the specific parameters of the reconfigurable transmission unit are: operating frequency 16GHz, unit period 9.3mm (0.5λ0). In order to meet the dual polarization requirements, the unit needs to be designed as a slender shape, so that two identical unit structures can be arranged orthogonally in the future. Figure 2 This refers to the process of improving the unit structure. Figure 2 In diagram (a), the initial unit structure consists of an active receiving dipole and a passive transmitting dipole. Although this structure can operate at 16 GHz, its operating bandwidth is very narrow. Therefore, a parasitic bypass was added next to the dipole, forming... Figure 2 The structure of (b) is shown. When the unit is working, the current of the transmitting and receiving dipoles is coupled to the parasitic bypass, forming a reverse current, which generates a new resonance and greatly expands the operating bandwidth.

[0043] Figure 2In (c), based on (b), a convex structure is used to connect the two ends of the dipole. The main function of this structure is to facilitate the subsequent design of the DC power supply line. Since the transmission unit integrates active devices, a corresponding bias circuit must be set on the unit structure to apply a reverse bias voltage to the varactor diode.

[0044] Unit bias circuit such as Figure 3 As shown, a connecting layer is added between the active dipole dielectric substrate and the ground plane for DC bias routing. A high-impedance microstrip line with a routing width of 0.2 mm is used. A fan-shaped stub, typically a quarter wavelength long, is added to the bias line to isolate DC signals. Its choke characteristic reduces the mutual interference between RF and DC signals. Since the fan-shaped stub is also an open structure and will radiate, it should be placed near the electric field zero point to minimize its impact on the overall cell's transmission performance. With the bias circuit determined, the final cell structure is also determined, as shown... Figure 4 As shown, this receiver-transmitter structure employs an active receiving dipole and a passive asymmetric transmitting dipole. The two dipoles are separated by a common ground point and connected through a metallized via; both are linearly polarized and arranged in the same direction. A shorter dipole is connected in parallel next to each dipole unit as a passive parasitic bypass. Two identical reconfigurable transmitting units are orthogonally arranged on the same plane to achieve dual polarization. Each unit has two independent bias lines, one for each polarization. For each receiver-transmitter structure, the middle portion of the active receiving dipole is grounded through the passive transmitting dipole, while a +1.3 / -1.3V DC bias voltage is applied across the active receiving dipole to control the diode state. The feed line ends with a quarter-wavelength fan-shaped stub with an open termination for filtering and rectification, suppressing radio frequency.

[0045] This example integrates two pin diodes in the receiving dipole. Based on the current reversal principle, the on / off state of the pin diodes in the transmission unit is controlled to achieve 1-bit encoding. To obtain high-performance and stable RTA device performance, the diode model selected in this design is MADP-000907-14020. In the actual simulation, the pin diodes are modeled as lumped elements. The initial value of the pin diodes in the on state is equivalent to a cascade of R = 7.8Ω and L = 30pH, and the initial value in the off state is equivalent to a cascade of C = 0.025F and L = 30pH.

[0046] In this example, the feed antenna is constructed from a circular waveguide corrugated horn antenna, and the designed corrugated horn is as follows: Figure 2-7 As shown, the horn opening radius is 21.20 mm and the length is 25.26 mm. It has three annular choke slots inside. Compared with traditional horn antennas, it has excellent performance in reducing edge diffraction, improving the symmetry of the lobe pattern and reducing cross polarization.

[0047] Before performing full-wave simulation of the entire reconfigurable transmission array, the DC bias network needs to be refined, and the DC routing of each array element needs to be planned. The bias network of the entire array is as follows: Figure 2-10 As shown, the entire reconfigurable array consists of 10×10 elements, with a total array size of 93mm×93mm. Due to the orthogonal placement of the two transceiver dipole structures, the space available for wiring is very limited, requiring a reasonable layout.

[0048] The convex structure added to the unit facilitates DC feeding. The structure connecting both ends of the pin is placed on the receiving layer, providing more space for DC traces. Similarly, to reduce the number of traces in the edge units, the bias network adopts a top-bottom symmetrical structure, ensuring a maximum of five DC traces per unit. The trace width is 0.2mm. On the same dielectric substrate, narrower traces have higher impedance to RF signals. Choosing 0.2mm high-impedance traces not only suppresses RF signal interference with DC signals but also facilitates trace layout. Simultaneously, to ensure that DC signals between different units do not interfere with each other, the spacing between adjacent feed lines is also 0.2mm. To allow for individual control of units with two polarization states and reduce cross-polarization, the DC traces for the two polarization states are independent. After the electromagnetic wave emitted by the feed horn reaches the transmission array, the unequal spatial distance from the feed horn to each transmission unit results in different spatial phase differences in the incident waves received by each transmission unit. Based on the position of the phase center of the feed horn and the beam direction of the planar transmission array antenna, the phase delay of each transmission element for the incident wave is calculated. Then, the transmission elements are designed to perform appropriate phase compensation for the incident wave, so that the transmitted electromagnetic waves are superimposed in phase in the designed direction, forming an equiphase surface, and finally obtaining the desired highly directional pencil beam. Before calculating the compensated phase, the focal length between the feed horn and the transmission array needs to be determined.

[0049] For traditional antennas, efficiency is crucial. Higher efficiency means better performance and more radiated energy. For transmission arrays, we primarily focus on aperture efficiency. This is a key indicator of the performance of a transmission array antenna. It can be calculated using the following formula:

[0050] η a =G m / G

[0051] G=4πD / λ 2 (1),

[0052] Where is the ideal gain of G, and G is the ideal gain. mThe measured gain of the array antenna is represented by F, and D is the array aperture size. Choosing the optimal focal length (F) is crucial for achieving higher efficiency. For a given feed mode, there exists an optimal F / D value. Through comprehensive analysis and optimization, the focal length that yields the best aperture efficiency is F = 85mm, with a focal diameter ratio of F / D = 0.91.

[0053] Once the focal length is determined, in order to obtain a high-gain plane wave in the desired direction, the phase of the RTA located at (m, n) can be written as:

[0054]

[0055] m and n are the labels relative to the array elements, and p is the element period, which is 9.3 mm. α is the reference phase of the central element, and β are the beam scanning angles in the x and y directions, respectively. For continuous phase modulation, different... This does not affect the performance of phase compensation. However, for 1-bit phase quantization, only 0° and 180° phase states are provided, and the phase distribution in equation (2) can be defined as:

[0056]

[0057] After the phase is determined, the whole system is array-coded.

[0058] The component performance under perpendicular incidence illumination was simulated using CST, with a periodic boundary condition used to simulate an infinite array. The simulated transmission amplitude and phase response of the component under perpendicular incidence illumination are as follows: Figure 5 As shown. The results indicate that, due to the current inversion mechanism, the device produces a similar amplitude response across a wide bandwidth between the two states, with a phase shift of 180 degrees. The insertion loss is -1.5 dB at 16 GHz, and the minimum insertion loss is 0.78 dB at 16.5 GHz. Clearly, the device exhibits dual-resonant characteristics at 15.5 and 16.5 GHz, as... Figure 5 As shown in (a). By observation Figure 6 The simulated current distribution in the diagram provides a better understanding of this. Both the active receiving dipole and the passive asymmetric transmitting dipole resonate at 15.5 GHz. Adding a parasitic bypass introduces an additional resonance at 16.5 GHz, with current coupled to the parasitic dipole. This dual-resonance characteristic improves the component's bandwidth performance, achieving a simulated 3 dB bandwidth of 1.8 GHz and a relative bandwidth of 11.25%. Furthermore, the transmission performance of the unit is very similar across both polarization states and different switching states, exhibiting good consistency.

[0059] Its return loss is as follows Figure 8As shown, the voltage level is below -28dB across the entire frequency band from 14.5GHz to 17.5GHz, which translates to a VSWR of less than 1.1 across the entire band. Figure 9 As can be seen, the radiation patterns of the E-plane and H-plane of the corrugated horn are very similar, indicating that the antenna has good symmetry in its radiation pattern. The peak gain of both the E-plane and H-plane patterns is 13.2 dB, the 3 dB beamwidth of the E-plane is 38.8 degrees, and the 3 dB beamwidth of the H-plane is 44.4 degrees.

[0060] Determine the initial phase as The operating frequency is 16 GHz. Since the simulation results for the two polarization states are very similar, to save time, only the effect of one polarization state is demonstrated here. The relationship between the gain and frequency of the reconfigurable transmission array in the 15-17 GHz range is as follows: Figure 11 As shown. The maximum gain measured at 16 GHz is 18.8 dB, the aperture efficiency is 24.5%, the measured 3 dB gain bandwidth is 1.3 GHz, and the relative bandwidth is 8.125%. At 16 GHz, the 3D radiation pattern obtained by encoding according to the phase requirements of different beam pointing angles and full-wave simulation is shown below. Figure 12 The scanning angle ranges from 0° to -50°.

[0061] Table 1 Beam Scanning Parameters

[0062]

[0063]

[0064] To visually demonstrate the beam changes, the radiation pattern of its E-plane and the corresponding radiation parameters are shown below. Figure 13 As shown in Table 1, the antenna gain at 0° is 18.8dB, and the gain at -50° is 15.7dB, with a scanning gain loss of 3.1dB. Here, because the phase is not continuously changing, the relationship between gain and scanning angle is different from that of a phased array antenna with continuous phase modulation.

[0065] The measured coplanar polarization and cross-polarization radiation patterns on the two principal planes are as follows: Figure 14 As shown. The 3dB beamwidth in the E-plane is 10.8°, and the maximum cross-polarization is -1.91dB. The 3dB beamwidth in the H-plane is 11.3°, and the maximum cross-polarization is -1.9dB.

[0066] This antenna achieves dual-polarized electronically controlled beam scanning by controlling the transmission phase of each element in two polarization directions through the switching of the PIN diodes on the control unit. Furthermore, its rational structural design achieves broadband antenna coverage and simplifies the feed network, making it highly practical.

Claims

1. A broadband dual-polarized reconfigurable transmission antenna array that is easily fed, characterized in that, The antenna is equipped with a feed antenna, a DC bias network, and two or more dual-polarized reconfigurable units. Each dual-polarized reconfigurable transmission antenna unit is formed by two identical reconfigurable transmission units orthogonally arranged on the same plane. Each reconfigurable transmission unit has two linearly polarized dipoles arranged in the same direction. The two dipoles form a receiving and transmitting structure with an active receiving dipole and a passive asymmetric transmitting dipole. The two dipoles are separated by a common ground point and connected by a metallized through-hole. A 7±0.5mm dipole is connected in parallel next to each dipole unit as a passive parasitic bypass to expand the antenna bandwidth. The receiving dipole integrates two pin diodes to control the on / off state of the pin diodes on the antenna unit based on the current reversal principle to achieve 1-bit encoding. The DC bias network consists of DC feeds corresponding to each dual-polarization reconfigurable unit. The DC feeds are narrow microstrip lines. Each dual-polarization reconfigurable unit has two independent DC feeds, each corresponding to a polarization. For each receiver-transmitter structure, the middle part of the active receiver dipole is grounded through the passive transmitter dipole. The two ends of the active receiver dipole are given a +1.3 / -1.3V DC bias voltage through the DC feeds to control the diode state. The DC feeds have a quarter-wavelength fan-shaped stub with an open circuit at the end for filtering, rectification, and RF suppression. The feed antenna uses a corrugated horn antenna as the feed source. The corrugated horn antenna is placed above the center of the reconfigurable transmission array as the feed source. The unit is encoded according to the phase distribution required for different beam pointing angles to perform phase compensation and achieve the effect of electronically controlled beam scanning.

2. The easily fed broadband dual-polarized reconfigurable transmission antenna array according to claim 1, characterized in that, To meet the dual-polarization requirement, the dual-polarization reconfigurable unit is designed in a slender shape, facilitating the subsequent orthogonal arrangement of two identical unit structures. Each dual-polarization reconfigurable unit consists of an active receiving dipole and a passive transmitting dipole. A parasitic bypass is added next to the dipole. During operation, the current of the receiving and transmitting dipoles couples to the parasitic bypass, forming a reverse current, generating a new resonance, and extending the operating band. A convex structure is used to connect the two ends of the dipole, facilitating the design of the subsequent DC feed line. A connection layer is added between the active dipole dielectric substrate and the ground plane for DC bias routing. The routing width is a 0.2mm high-impedance microstrip line. A fan-shaped choke is added to the bias line, with a stub length of one-quarter wavelength.

3. The easily fed broadband dual-polarized reconfigurable transmission antenna array according to claim 2, characterized in that, The receiving dipole integrates two pin diodes. Based on the current reversal principle, the on / off state of the transmission unit pin diodes is controlled to achieve 1-bit encoding. In order to obtain high performance and stable RTA component performance, the diode model selected is MADP-000907-14020. In the actual simulation, the pin diodes are modeled as lumped elements. The initial value of the pin diodes in the on state is equivalent to a cascade of R = 7.8Ω and L = 30 pH, and the initial value in the off state is equivalent to a cascade of C = 0.025 F and L = 30 pH.

4. The easily fed broadband dual-polarized reconfigurable transmission antenna array according to claim 1, characterized in that, The feed antenna is composed of a circular waveguide corrugated horn antenna. The horn opening radius is 21.20 mm and the length is 25.26 mm. There are 3 annular choke slots inside.

5. The easily fed broadband dual-polarized reconfigurable transmission antenna array according to claim 1, characterized in that, The bias network adopts a top-bottom symmetrical structure to ensure that there are a maximum of 5 DC traces on the unit. The trace width is 0.2mm, and the spacing between adjacent feed lines is also 0.2mm. The DC traces of the two polarization states are independent of each other.

6. The easily fed broadband dual-polarized reconfigurable transmission antenna array according to claim 1, characterized in that, After the electromagnetic wave emitted by the feed horn reaches the transmission array, the incident wave received by each transmission element has a different spatial phase difference due to the unequal spatial distance between the feed horn and each transmission element. Based on the position of the phase center of the feed horn and the direction of the radiation beam of the planar transmission array antenna, the phase delay of each transmission element to the incident wave is calculated. Then, the transmission element is designed to perform appropriate phase compensation for the incident wave, so that the transmitted electromagnetic waves can be superimposed in phase in the designed direction to form an equiphase surface, and finally obtain the required high-directional pencil beam. Before calculating the compensation phase, the focal length between the feed horn and the transmission array needs to be determined. The aperture efficiency of a transmission array is calculated using the following formula: (1)， Among them is Ideal gain, Let F represent the measured gain of the array antenna, and D be the array aperture size. To achieve higher efficiency, selecting the optimal focal length F is crucial. For a given feeding mode, there exists an optimal F / D value. The focal length for optimal aperture efficiency is F = 85mm, with a focal length-to-diameter ratio of F / D = 0.

91. After determining the focal length, to obtain a high-gain plane wave in the desired direction, the phase of the RTA at (m, n) can be written as: (2)， m and n are the labels relative to the parameter array elements, and p is the element period. It is the reference phase of the central unit. and These are the beam scanning angles in the x and y directions. For continuous phase modulation, different... This does not affect the performance of phase compensation; however, for 1-bit phase quantization, only 0° and 180° phase states are provided, and the phase distribution in equation (2) can be defined as: (3)， After the phase is determined, the entire array is encoded. The antenna controls the transmission phase of each unit in two polarization directions by switching the PIN diode on the control unit, thereby realizing dual-polarized electronically controlled beam scanning.

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