Easily-fed broadband dual-polarization reconfigurable transmission antenna array

Abstract

The invention relates to the technical field of dual-polarized antenna manufacturing, in particular to an easy-to-feed broadband dual-polarized reconfigurable transmission antenna array, which is provided with a feed source antenna, a direct current bias network and more than two dual-polarized reconfigurable units, wherein each dual-polarization reconfigurable transmission antenna unit is formed by orthogonally arranging two identical reconfigurable transmission units on the same plane, and each reconfigurable transmission unit is internally provided with two linearly polarized dipoles which are arranged along the same direction; the two dipoles form a receiving and transmitting structure of an active receiving dipole and a passive asymmetric transmitting dipole, the two dipoles are separated through a common grounding point and connected through a metalized through hole, and a dipole is connected beside each dipole unit in parallel to serve as a passive parasitic bypass so as to expand the bandwidth of the antenna. The receiving dipole is integrated with two pin diodes.

Description

Technical field:

[0001] The invention relates to the technical field of dual-polarization antenna manufacturing, in particular to a broadband dual-polarization reconfigurable transmission antenna array which is easy to feed. Background technology:

[0002] Antennas are the terminals of microwave systems. Wireless communication is achieved by converting microwave signals into electromagnetic waves propagating in free space. Antennas are the hub of microwave systems and free space. And as communication systems continue to develop, the demand for antenna performance is getting higher and higher. In order to meet the stringent requirements for antennas in fields such as long-distance communication, radar detection, microwave landing, and electronic interference countermeasures, it is necessary to design some antennas with strong directivity and high gain, with advantages such as multi-polarization, low profile, and electrically controllable beam scanning to compensate for problems such as spatial attenuation. Phased array antennas can quickly switch beam scanning directions and beam shapes, and have advantages such as high gain, low profile, and easy processing. However, the phase shifting structure of phased array antennas mostly uses phase shifter chips to independently control the phase change of each unit. Phase shifter chips are expensive and require complex feeding networks to use. At the same time, phase shifter chips have different degrees of insertion loss, which leads to increased antenna loss and reduced efficiency.

[0003] Reconfigurable array antennas are widely used in the field of antenna design, such as superlens, radar antenna cover, and polarization conversion, by loading active devices such as MEMES, varactor and PIN diode on traditional units, and changing the current distribution and current flow direction of electromagnetic radiators by adjusting the state of active devices. Through the specific design of the unit phase, a radiation beam with high gain is obtained while achieving the effect of electrically controlled array beam scanning. It has the advantages of simple structure, low processing cost and process requirements, no complex feeding network, and easy integration with microstrip circuits.

[0004] From the existing research results, it can be seen that the use of diodes to control metasurfaces has many advantages over other control methods, such as simple point-by-point control, low production cost and control cost. However, most of the current reconfigurable metasurface antennas are single-polarized, and the technical solution of dual-polarized reconfigurable metasurfaces has the problem that it can only control one row or one column of array elements on the array, and cannot encode any array element individually. In addition, the DC feed network does not have a choke structure, which is easy to affect the DC signal. Summary of the invention:

[0005] In view of the shortcomings and deficiencies in the prior art, the present invention proposes a broadband dual-polarization reconfigurable transmission antenna array that is easy to feed.

[0006] The present invention is achieved by the following measures:

[0007] A broadband dual-polarization reconfigurable transmission antenna array that is easy to feed, characterized in that it is provided with: a feed antenna, a DC bias network and more than two dual-polarization reconfigurable units, wherein the more than two dual-polarization reconfigurable transmission antenna units, wherein each dual-polarization reconfigurable transmission antenna unit is formed by two identical reconfigurable transmission units arranged orthogonally in the same plane, wherein the reconfigurable transmission unit is provided with two linearly polarized dipoles arranged in the same direction, the two dipoles form a receiving and transmitting structure 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, and a 7±0.5mm dipole is connected in parallel next to each dipole unit as a passive parasitic bypass to expand the antenna bandwidth, and the receiving dipole integrates two pin diodes to control the on and off of the antenna unit pin tube based on the current reversal principle to realize 1-bit encoding;

[0008] The DC bias network is composed of a DC feeder corresponding to each dual-polarization reconfigurable unit. The DC feeder adopts a narrow microstrip line. Each dual-polarization reconfigurable unit has two independent DC feeders, each of which is used to correspond to one polarization. For each receiving and transmitting structure, the middle part of the active receiving dipole is grounded through the passive transmitter dipole, and a +1.3 / -1.3V DC bias voltage is applied to both ends of the active receiving dipole through the DC feeder to control the diode state. The end of the DC feeder has a quarter-wavelength fan-shaped branch with an open terminal for filtering, rectifying and suppressing radio frequency.

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

[0010] In order to meet the dual-polarization requirements, the dual-polarization reconfigurable unit in the present invention needs to be designed into a slender type, so that two identical unit structures can be arranged orthogonally in the subsequent process. Each dual-polarization reconfigurable unit is composed 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 dipole is coupled to the parasitic bypass to form a reverse current, thereby generating a new resonance and greatly expanding the working band. A convex structure is used to connect the two ends of the dipole, which is convenient for the subsequent DC feed line design. Since the transmission unit integrates active devices, it must be connected at the unit junction. A corresponding bias circuit is arranged on the structure to apply a reverse bias voltage to the varactor diode, wherein a connection layer is added between the active dipole dielectric plate and the ground layer for DC bias routing, and the routing width is a high-impedance microstrip line of 0.2 mm. A fan-shaped choke is added to the bias line, and the branch length is usually one-quarter of the wavelength, which has the effect of isolating direct current. The choke characteristic is used to reduce the mutual influence between the RF signal and the DC signal. Since the fan-shaped branch is also an open structure and will radiate, it should be placed near the zero point of the electric field to reduce its influence on the transmission performance of the entire unit.

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

[0012] The feed antenna in the present invention is composed of a circular waveguide corrugated horn antenna. The horn opening radius of the corrugated horn is 21.20 mm, the length is 25.26 mm, and there are 3 annular choke slots inside. Compared with the traditional horn antenna, it has the excellent performance of reducing edge diffraction, improving the symmetry of the lobe pattern and reducing cross polarization.

[0013] In order to reduce the number of routing lines of edge units, the DC feeder network of the present invention adopts a vertically symmetrical structure for the bias network, so as to ensure that there are at most 5 DC routing lines on the unit, and the width of the routing line is 0.2 mm. On the same dielectric board, the narrower the routing line, the higher the impedance to the radio frequency signal. Selecting a 0.2 mm high-impedance routing line can not only suppress the interference of the radio frequency signal on the DC signal, but also facilitate the layout of the routing. 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 feeders is also 0.2 mm. In order to be able to individually control the units in two polarization states and reduce cross polarization at the same time, the DC routing lines in the two polarization states are independent of each other.

[0014] In the present invention, after the electromagnetic wave emitted by the feed horn reaches the transmission array, the spatial distances from the feed horn to each transmission unit are not equal, resulting in different spatial phase differences in the incident waves received by each transmission unit. According to 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 unit to the incident wave is calculated, and then the transmission unit is designed to perform appropriate phase compensation on the incident wave, so that the electromagnetic wave after transmission can be superimposed in phase in the designed direction to form an equal phase surface, and finally the desired highly directional pencil beam is obtained. Before calculating the compensation phase, it is necessary to determine the focal length between the feed horn and the transmission array;

[0015] For traditional antennas, the efficiency of the antenna is crucial. The higher the efficiency of the antenna, the better its performance and the more energy it radiates. For transmission arrays, the main focus is on its aperture efficiency, which can be calculated using the following formula:

[0016] η a =G m / G

[0017] G=4πD / λ 2 (1)

[0018] where G is the ideal gain, G m represents the measured gain of the array antenna, and D is the array aperture size. In order to obtain higher efficiency, it is crucial to select the optimal focal length (F). For a given feeding mode, there is an optimal F / D value. The focal length with the best aperture efficiency is F = 85 mm, and the focal diameter ratio F / D = 0.91. After determining the focal length, in order 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, n are the numbers of the array elements, and p is the unit period, which is 9.3 mm. is the reference phase of the center unit, α and β are the beam scanning angles in the x and y directions, and for continuous phase modulation, different It 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 the two polarization directions by turning on and off the PIN tube on the control unit, thereby realizing dual-polarization electrically controlled beam scanning.

[0023] Compared with the prior art, the present invention has the significant advantages of reasonable structure, reliable operation and the like. Description of the drawings:

[0024] Attached Figure 1 It is a structural schematic diagram of the present invention.

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

[0026] Attached Figure 3 It is a structural diagram of the bias circuit of the reconfigurable transmission unit in the present invention.

[0027] Attached Figure 4 is a schematic diagram of the layer structure of the reconfigurable transmission unit in the present 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] Attached Figure 5 is a simulated S parameter curve diagram of the reconfigurable transmission unit in an embodiment of the present invention, wherein Figure 5 (a) is the return loss and transmission amplitude curve, (b) is the transmission phase curve.

[0029] Attached Figure 6 is a current distribution diagram of a 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] Attached Figure 7 is a structural diagram of a corrugated speaker in an embodiment of the present invention, wherein Figure 7 (a) is a schematic diagram of the side structure, and (b) is a top view.

[0031] Attached Figure 8 4 is a return loss curve of the corrugated speaker in the embodiment of the present invention.

[0032] Attached Fig. 9 It is the directional diagram of the corrugated speaker at 16 Hz in the embodiment of the present invention.

[0033] Attached Fig.10 4 is a structural diagram of a DC bias network in an embodiment of the present invention.

[0034] Attached Fig.11 2 is a gain frequency curve diagram in an embodiment of the present invention.

[0035] Attached Fig.12 is the 16 Hz encoding and 3D directional diagram in the embodiment of the present invention, wherein Fig.12 (a) is a schematic diagram of a scanning angle of 0°, (b) is a schematic diagram of a scanning angle of -10°, (c) is a schematic diagram of a scanning angle of -20°, (d) is a schematic diagram of a scanning angle of -30°, (e) is a schematic diagram of a scanning angle of -40°, and (f) is a schematic diagram of a scanning angle of -50°.

[0036] Attached Fig.13 It is a beam scanning curve diagram at 16 Hz in an embodiment of the present invention.

[0037] Attached Fig.14 is the main plane radiation pattern in the embodiment of the present invention, wherein Fig.14 (a) is the E surface, and (b) is the H surface.

[0038] Figure numerals: corrugated horn 1, DC bias network 2, vertical polarization receiving dipole 3, horizontal polarization receiving dipole 4, receiving patch 5, bias circuit 6, connection layer 7, ground 8, transmitting patch 9. Specific implementation method:

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

[0040] Example:

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

[0042] The specific parameters of the reconfigurable transmission unit in this example are: operating frequency 16 GHz, unit period 9.3 mm (0.5λ0). In order to meet the dual-polarization requirements, the unit needs to be designed to be slender to facilitate the subsequent orthogonal arrangement of two identical unit structures. Figure 2 Improve the process for unit structure. Figure 2 (a) is the original unit structure, which consists of an active receiving dipole and a passive transmitting dipole. Although this structure can work at 16GHz, the working frequency band is very narrow, so a parasitic bypass is added next to the dipole to form Figure 2 When the unit is working, the current of the transmitting and receiving dipoles is coupled to the parasitic bypass, forming a reverse current, generating a new resonance, and greatly expanding the working 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 DC feeder circuit design. 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 connection layer is added between the active dipole dielectric plate and the ground layer for DC bias routing. The routing width is a high-impedance microstrip line of 0.2mm. A fan-shaped choke is added to the bias line. Its long branches are usually a quarter of a wavelength long, which has the effect of isolating DC. Its choke characteristics are used to reduce the mutual influence between RF signals and DC signals. Since the fan-shaped branches are also an open structure and will radiate, they should be placed near the zero point of the electric field to reduce their influence on the transmission performance of the entire unit. The bias circuit is determined, and the final unit structure is also determined, as shown in Figure 4 As shown. The structure adopts a receiving-transmitting structure 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. They are both 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 transmission units are arranged orthogonally in the same plane to achieve dual polarization. There are two independent bias lines in each unit, one for each polarization. For each receiver-transmitter structure, the middle part of the active receiving dipole is grounded through the passive transmitter dipole, and a +1.3 / -1.3V DC bias voltage is applied to both ends of the active receiving dipole to control the diode state. There is a quarter-wavelength fan-shaped branch with an open terminal at the end of the feed line for filtering and rectification to suppress radio frequency.

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

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

[0047] Before performing full-wave simulation on the entire reconfigurable transmission array, the DC bias network needs to be improved and the DC routing of each array element needs to be planned. Figure 2-10 As shown in the figure, the entire reconfigurable array consists of 10×10 units, and the size of the entire array is 93mm×93mm. Since the two transmit and receive dipole structures are placed orthogonally, the space left for routing is very limited, and a reasonable layout is required.

[0048] The convex structure added to the unit is to facilitate DC feeding. The structure connecting the two ends of the pin tube is placed in the receiving layer, so that there is more space for DC routing. Similarly, in order to reduce the number of routing lines of the edge unit, the bias network adopts a symmetrical structure up and down, so as to ensure that there are only 5 DC routing lines on the unit at most. The width of the routing line is 0.2mm. On the same dielectric board, the narrower the routing line, the higher the impedance to the RF signal. Selecting a 0.2mm high-impedance routing line can not only suppress the interference of the RF signal on the DC signal, but also facilitate the layout of the routing line. 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 be able to control the units in two polarization states separately and reduce cross-polarization at the same time, the DC routing lines in the two polarization states are independent of each other. After the electromagnetic wave emitted by the feed horn reaches the transmission array, due to the unequal spatial distance from the feed horn to each transmission unit, the incident wave received by each transmission unit has different spatial phase differences. According to 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 unit to the incident wave is calculated, and then the transmission unit is designed to perform appropriate phase compensation on the incident wave, so that the electromagnetic wave after transmission can be superimposed in phase in the designed direction to form an equal phase surface, and finally the required highly directional pencil beam is obtained. Before calculating the compensation phase, it is necessary to determine the focal length between the feed horn and the transmission array.

[0049] For traditional antennas, the efficiency of the antenna is very important. The higher the efficiency of the antenna, the better its performance and the more energy it radiates. For transmission arrays, we mainly focus on its aperture efficiency. This is an important indicator to describe the performance of transmission array antennas. It can be calculated by the following formula:

[0050] η a =G m / G

[0051] G=4πD / λ 2 (1)

[0052] where G is the ideal gain, G mrepresents the measured gain of the array antenna, and D is the array aperture size. In order to obtain higher efficiency, it is crucial to select the optimal focal length (F). For a given feeding mode, there is an optimal F / D value. After comprehensive analysis and optimization, the focal length that can obtain the best aperture efficiency is F = 85mm, and the focal diameter ratio F / D = 0.91.

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

[0054]

[0055] m, n are the numbers of the array elements, and p is the unit period, which is 9.3 mm. is the reference phase of the center unit, α and β are the beam scanning angles in the x and y directions. For continuous phase modulation, different It 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 array is encoded.

[0058] The performance of the element at normal incidence is simulated using CST, using periodic boundary conditions to simulate an infinite array. The simulated transmission amplitude and phase response of the element at normal incidence is shown in Figure 2. Figure 5 The results show that due to the current inversion mechanism, the component produces a similar amplitude response in a wide frequency band between the two states with a phase shift of 180 degrees. The insertion loss at 16 GHz is -1.5 dB, and the minimum insertion loss is 0.78 dB at 16.5 GHz. It is obvious that the component exhibits dual resonance characteristics at 15.5 and 16.5 GHz, as shown in Figure 2. Figure 5 (a) is shown. By observing Figure 6 This can be better understood by looking at the simulated current distribution in Figure 1. Both the active receiving dipole and the passive asymmetric transmitting dipole resonate at 15.5 GHz. After adding the parasitic bypass, an additional resonance is introduced at 16.5 GHz, with current coupling to the parasitic dipole. The dual resonance characteristic improves the bandwidth performance of the component, with a simulated 3 dB bandwidth of 1.8 GHz and a relative bandwidth of 11.25%. In addition, the transmission performance of the unit in the two polarization states and different switching states is very close, with good consistency.

[0059] Its return loss is Figure 8As shown in the figure, it can be seen that in the entire frequency band from 14.5GHz to 17.5GHz, it is lower than -28dB, which is converted into a standing wave ratio and is less than 1.1 in the entire frequency band. Fig. 9 It can be seen that the radiation patterns of the E and H surfaces of the corrugated horn are very similar, which shows that the radiation pattern of the antenna has good symmetry. The peak gain of the E and H patterns is 13.2dB, the 3dB beamwidth of the E surface is 38.8 degrees, and the 3dB beamwidth of the H surface is 44.4 degrees.

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

[0061] Table 1 Beam scanning parameters

[0062]

[0063]

[0064] In order to intuitively show the changes in the beam, the radiation pattern of the E plane and the corresponding radiation parameters are as follows: Fig.13 As shown in Table 1, the antenna gain at 0° is 18.8dB, and the gain is 15.7dB when scanning to -50°, with a scanning gain loss of 3.1dB. Since the phase does not change continuously here, the relationship between gain and scanning angle is different from that of the phased array antenna with continuous phase modulation.

[0065] The measured coplanar polarization and cross-polarization radiation patterns on the two main planes are shown in Fig.14 The 3dB beamwidth of the E plane is 10.8°, and the maximum cross-polarization is -1.91dB. The 3dB beamwidth of the H plane is 11.3°, and the maximum cross-polarization is -1.9dB.

[0066] The antenna controls the transmission phase of each unit in two polarization directions by turning on and off the PIN tube on the control unit, thereby realizing dual-polarization electrically controlled beam scanning. The antenna is broadband and the feeding network is simplified through reasonable structural design, which has high practical value.

Claims

1. A broadband dual-polarization reconfigurable transmission antenna array that is easy to feed, characterized in that: The invention is provided with: a feed antenna, a DC bias network and two or more dual-polarization reconfigurable units, wherein the two or more dual-polarization reconfigurable transmission antenna units, wherein each dual-polarization reconfigurable transmission antenna unit is formed by two identical reconfigurable transmission units arranged orthogonally in the same plane, wherein the reconfigurable transmission unit is provided with two linearly polarized dipoles arranged in the same direction, wherein the two dipoles form a receiving and transmitting structure of an active receiving dipole and a passive asymmetric transmitting dipole, wherein the two dipoles are separated by a common ground point and connected by a metallized through hole, and a 7±0.5 mm dipole is connected in parallel next to each dipole unit as a passive parasitic bypass to expand the antenna bandwidth, and the receiving dipole is integrated Two PIN diodes are used to control the on and off of the PIN diodes on the antenna unit based on the current reversal principle to realize 1-bit encoding; the DC bias network is composed of a DC feeder corresponding to each dual-polarization reconfigurable unit, and the DC feeder adopts a narrow microstrip line. There are two independent DC feeders in each dual-polarization reconfigurable unit, and each DC feeder is used to correspond to one polarization. For each receiving and transmitting structure, the middle part of the active receiving dipole is grounded through the passive transmitter dipole, and the two ends of the active receiving dipole are applied with a +1.3 / -1.3V DC bias voltage through the DC feeder to control the diode state. The end of the DC feeder has a quarter-wavelength fan-shaped branch with an open terminal for filtering, rectifying and suppressing radio frequency; The feed antenna uses a corrugated horn antenna as a feed source, and the corrugated horn antenna is placed above the center of the reconfigurable transmission array as a feed source. The unit is encoded according to the phase distribution required for different beam pointing angles to perform phase compensation, thereby achieving the effect of electrically controlled beam scanning.

2. The easy-to-feed broadband dual-polarization reconfigurable transmission antenna array according to claim 1, characterized in that: In order to meet the dual-polarization requirements, the dual-polarization reconfigurable unit is designed to be slender, which is convenient for the subsequent orthogonal arrangement of two completely 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 working, the current of the transmitting and receiving dipoles is coupled to the parasitic bypass to form a reverse current, generate a new resonance, and expand the working band. A convex structure is used to connect the two ends of the dipole to facilitate the subsequent DC feed line design. A connecting layer is added between the active dipole dielectric plate and the ground formation for DC bias routing. The routing width is a high-impedance microstrip line of 0.2 mm. A fan-shaped choke is added to the bias line, and the branch length is one-quarter of a wavelength.

3. The easy-to-feed broadband dual-polarization 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 and off of the pin tube of the transmission unit is controlled to realize 1-bit encoding. In order to obtain high performance and stable RTA component performance, the selected diode model is MADP-000907-14020. In the actual simulation, the pin tube is modeled as a lumped element. The initial value of the pin tube in the on state is equivalent to the cascade of R=7.8Ω and L=30pH, and the initial value in the OFF state is equivalent to the cascade of C=0.025F and L=30pH.

4. The easy-to-feed broadband dual-polarization 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 of the corrugated horn is 21.20mm, the length is 25.26mm, and there are 3 annular choke slots inside.

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

6. The easy-to-feed broadband dual-polarization 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 spatial distance from the feed horn to each transmission unit is not equal, resulting in different spatial phase differences in the incident waves received by each transmission unit. According to 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 unit to the incident wave is calculated, and then the transmission unit is designed to perform appropriate phase compensation on the incident wave, so that the electromagnetic wave after transmission can be superimposed in phase in the designed direction to form an equal phase surface, and finally the required highly directional pencil beam is obtained. Before calculating the compensation phase, it is necessary to determine the focal length between the feed horn and the transmission array; The aperture efficiency for the transmission array is calculated using the following formula: or a =G m / G G=4πD / λ 2 (1), where G is the ideal gain, G m represents the measured gain of the array antenna, and D is the array aperture size. In order to obtain higher efficiency, it is crucial to select the optimal focal length (F). For a given feeding mode, there is an optimal F / D value. The focal length with the best aperture efficiency is F = 85 mm, and the focal diameter ratio F / D = 0.

91. After determining the focal length, in order to obtain a high-gain plane wave in the desired direction, the phase of the RTA at (m, n) can be written as: m, n are the numbers of the array elements, and p is the unit period, which is 9.3 mm. is the reference phase of the center unit, α and β are the beam scanning angles in the x and y directions, and for continuous phase modulation, different It 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: After the phase is determined, the entire array is encoded. The antenna controls the transmission phase of each unit in the two polarization directions by turning on and off the PIN tube on the control unit, thereby realizing dual-polarization electrically controlled beam scanning.

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