Wire-polarized in-band scattering reconfigurable radiation time-sharing control array antenna

Abstract

The application discloses a linear polarization in-band scattering reconfigurable radiation time-sharing control array antenna and belongs to the technical field of antenna engineering, which comprises an antenna unit and a one-to-sixteen power divider, wherein the antenna unit is connected with the one-to-sixteen power divider; the antenna unit comprises a radiation patch one, a dielectric substrate one, a radiation patch two, a dielectric substrate two, a feed coupling branch, a feed metal column, a dielectric substrate three, a metal floor with holes and a dielectric substrate four; the bottom of the dielectric substrate four is provided with a PIN tube one, a PIN tube two, a feed transmission line, a DC biasing device, a reflective phase shifter and a low-pass filter; the DC biasing device is connected with the reflective phase shifter and the feed transmission line through the low-pass filter; and the feed metal column passes through the dielectric substrate three, the metal floor with holes, the dielectric substrate four in sequence and is connected with the feed transmission line. The application can not only guarantee the normal radiation efficiency of the antenna, but also effectively improve the reconfigurability of the antenna scattering.

Description

Technical Field

[0001] This invention relates to the field of antenna engineering technology, and in particular to a linearly polarized in-band scattering reconfigurable divergence time-division modulated array antenna. Background Technology

[0002] Antenna-based wireless communication systems are increasingly being incorporated into many low-visibility platform structures, and the scattering contribution of antennas in the platform is gradually increasing due to their reciprocity in transmitting and receiving electromagnetic signals.

[0003] Antenna scattering mainly consists of two parts: one is the scattering field of antenna structure mode terms related to the antenna structure, and the other is the scattering field of antenna mode terms generated by secondary radiation due to antenna load mismatch. Therefore, the radiation and scattering processes partially overlap. Without special design, dynamic control of antenna scattering performance can severely affect the antenna's radiation performance. Thus, for scattering control within the band of linearly polarized antennas, much attention is paid to cross-polarization.

[0004] In existing technologies, there are roughly two methods for controlling co-polarization scattering within the linear polarization band: one is to apply a metasurface coating above the antenna. Liu Ying's research group disclosed in their published paper that they loaded a liquid metal metasurface onto a microstrip slot antenna, achieving scattering reduction and changes in the scattering pattern by altering the filling state of the liquid metal. The other method is to change the antenna structure. Chen Yikai et al. proposed a 1-bit reconfigurable linear polarization unit in their paper, achieving active adjustment of the scattered beam by changing the state of the switching diode.

[0005] However, the use of reconfigurable cladding in the aforementioned papers increases the antenna's profile height or alters its structure by switching diodes, resulting in differences in radiation performance between the two structures. Furthermore, the functionality is limited due to the 1-bit reflection phase, leading to the formation of symmetrical dual beams during scattered beam scanning.

[0006] Existing linearly polarized band co-polarized scattering reconfigurable antennas suffer from drawbacks such as complex structural design, low antenna radiation efficiency, limited scattering control states, and mutual interference of antenna divergence characteristics.

[0007] Chinese patent application document CN119093036A, published on December 6, 2024, discloses an antenna array based on liquid metal with polarization reconfigurable radiation and scattering integration. It includes antenna subarrays placed in four quadrants of a Cartesian coordinate system. The antenna subarrays include a feed network layer with an adjustable phase shifter on the feed network layer. The adjustable phase shifter contains a movable liquid metal segment. By adjusting the position of the liquid metal segment, the signal transmission path of the feed network can be changed, so that the polarization mode of the radiated electromagnetic wave of the antenna array can be adjusted.

[0008] The patent application discloses a polarization-reconfigurable radiation and scattering integrated antenna array based on liquid metal. It uses liquid metal to control the feed network to achieve antenna polarization reconfiguration, and broadens the operating bandwidth for radar scattering reduction through the unequal height placement of subarrays. However, the inability to dynamically switch between radiation and scattering states affects the antenna's normal radiation efficiency. Summary of the Invention

[0009] To overcome the shortcomings of the prior art, this invention provides a linearly polarized in-band scattering reconfigurable divergence time-division controlled array antenna. This invention enables dynamic switching between radiation and scattering states within the same antenna aperture as needed, ensuring both the normal radiation efficiency of the antenna and effectively improving the reconfigurability of antenna scattering.

[0010] This invention is achieved through the following technical solution:

[0011] A linearly polarized in-band scattering reconfigurable divergence time-division modulated array antenna includes 4×4 antenna elements and a 1-to-16 power divider. The antenna elements are connected to the 1-to-16 power divider. Each antenna element includes, from top to bottom, a radiating patch 1, a dielectric substrate 1, a radiating patch 2, a dielectric substrate 3, a perforated metal ground plane, and a dielectric substrate 4. The bottom of the dielectric substrate 4 is provided with a PIN diode 1, a PIN diode 2, a feed transmission line, a DC bias, a reflective phase shifter, and a low-pass filter. The DC bias is connected to the reflective phase shifter and the feed transmission line through the low-pass filter. The reflective phase shifter is provided with a varactor diode 1 and a varactor diode 2. The feed metal pillar passes through the dielectric substrate 3, the perforated metal ground plane, and the dielectric substrate 4 in sequence and is connected to the feed transmission line.

[0012] The reflective phase shifter includes a long metal microstrip line, a first short metal microstrip line, and a second short metal microstrip line. The positive terminal of the first varactor diode is connected to the first short metal microstrip line, and the negative terminal of the first varactor diode is connected to the long metal microstrip line. The positive terminal of the second varactor diode is connected to the second short metal microstrip line, and the negative terminal of the second varactor diode is connected to the long metal microstrip line.

[0013] The size of the first radiation patch is smaller than that of the second radiation patch.

[0014] The PIN tube is placed parallel to the power supply transmission line, dividing the power supply transmission line into two parts. One end of the power supply transmission line is connected to the power supply metal post, and the other end of the power supply transmission line is close to the radiation port.

[0015] The second PIN tube is placed perpendicular to the power supply transmission line. One end of the second PIN tube is connected to the power supply transmission line connected to the power supply metal post, and the other end of the second PIN tube is connected to the reflective phase shifter.

[0016] The negative terminal of the first PIN diode is located at one end of the feed transmission line connected to the feed metal post, and the positive terminal of the first PIN diode is located at the end of the feed transmission line away from the feed metal post.

[0017] The negative terminal of the second PIN diode is connected to a reflective phase shifter, and the positive terminal of the second PIN diode is connected to one end of a feed transmission line that is connected to a feed metal post.

[0018] The dielectric constants of dielectric substrate one, dielectric substrate two, and dielectric substrate three are all 2.65, and the dielectric constant of dielectric substrate four is 6.15.

[0019] Both the first and second radiating patches are rectangular patches.

[0020] The PIN diode mentioned in this invention refers to a switching diode.

[0021] The beneficial effects of this invention are mainly reflected in the following aspects:

[0022] 1. Compared with the prior art, the present invention enables dynamic switching between radiation and scattering states within the same antenna aperture as needed, which can both ensure the normal radiation efficiency of the antenna and effectively improve the reconfigurability of antenna scattering.

[0023] 2. In this invention, the reflective phase shifter includes a long metal microstrip line, a first short metal microstrip line, and a second short metal microstrip line. The positive terminal of the first varactor diode is connected to the first short metal microstrip line, and the negative terminal of the first varactor diode is connected to the long metal microstrip line. The positive terminal of the second varactor diode is connected to the second short metal microstrip line, and the negative terminal of the second varactor diode is connected to the long metal microstrip line. Through a shared long metal microstrip line and two short metal microstrip lines, combined with two varactor diodes, a balanced reflective circuit is formed, which can provide a stable and adjustable phase shift over a wide frequency band. By independently controlling the capacitance values ​​of the two varactor diodes, the phase of the reflected signal can be precisely controlled, which is beneficial for the flexible control of the antenna's scattered beam.

[0024] 3. In this invention, the size of radiating patch one is smaller than that of radiating patch two. This asymmetrical stacked structure broadens the impedance bandwidth of the antenna. The smaller upper radiating patch one and the larger lower radiating patch two work together to excite multiple adjacent resonant modes and merge them, thereby enabling the antenna to maintain good matching performance over a wider frequency range.

[0025] 4. This invention changes the reflection phase of the antenna mode term scattering field by a varactor diode, which has a continuous phase change of 360°, thus improving the reconfigurability of scattering control.

[0026] 5. This invention enables antenna function switching and on-demand reconstruction of scattering characteristics simply by controlling the DC bias voltage, providing flexible control.

[0027] 6. This invention uses a dual-PIN diode on the feed transmission line to switch between radiation and scattering states. During radiation, the scattering control section does not affect the radiation performance. Radiation and scattering are applied with the same aperture and structure, requiring no additional cladding structure and not affecting the normal radiation of the antenna.

[0028] 7. This invention achieves a continuous linear phase change of 360° in-band co-polarized reflection phase of the antenna element through a reflective phase shifter with continuous linear phase change. For electromagnetic wave vertical incidence, it can achieve a reduction in single-station RCS, i.e., single-station radar cross section, and a ±45° scattered beam deflection capability.

[0029] 8. In this invention, the dielectric constants of dielectric substrate one, dielectric substrate two, and dielectric substrate three are all 2.65, and the dielectric constant of dielectric substrate four is 6.15. The use of lower dielectric constants for dielectric substrate one, dielectric substrate two, and dielectric substrate three is beneficial for reducing the confinement of surface waves, improving the radiation efficiency of the antenna, and widening the beamwidth. The use of higher dielectric constants for dielectric substrate four is beneficial for achieving miniaturization and compact design of the antenna element and the entire array. Through the design of using a mixture of high and low dielectric constants, an optimal balance is achieved between performance and size. Attached Figure Description

[0030] The present invention will now be further described in detail with reference to the accompanying drawings and specific embodiments:

[0031] Figure 1 This is an exploded view of the present invention;

[0032] Figure 2 This is a schematic diagram showing the connection between the DC biaser and the reflective phase shifter of the present invention;

[0033] Figure 3 This is a schematic diagram of the 1 to 16 power divider of the present invention connected to a 4×4 array antenna;

[0034] Figure 4 This is a schematic diagram of the radiation gain of the antenna element of the present invention;

[0035] Figure 5 This is a characteristic graph of the capacitance of the varactor diode of the present invention as a function of voltage.

[0036] Figure 6 This is a schematic diagram of the reflection amplitude characteristics of the antenna element of the present invention;

[0037] Figure 7 This is a schematic diagram of the reflection phase characteristics of the antenna element of the present invention;

[0038] Figure 8 This is a schematic diagram of the radiation characteristics of the array antenna of the present invention under radiation conditions;

[0039] Figure 9 This is a schematic diagram of the monostatic radar cross section of the array antenna of the present invention under different bias conditions in the scattering state;

[0040] Figure 10 This is a schematic diagram of the deflection of the scattered beam of the array antenna of the present invention under scattering conditions;

[0041] The diagram is labeled as follows: 1. Radiating patch one, 2. Dielectric substrate one, 3. Radiating patch two, 4. Dielectric substrate two, 5. Feed coupling stub, 6. Feed metal pillar, 7. Dielectric substrate three, 8. Perforated metal ground plane, 9. Dielectric substrate four, 10. Feed transmission line, 11. PIN diode one, 12. Reflective phase shifter, 13. Low-pass filter, 14. DC bias, 15. 1-to-16 power divider, 16. SMP RF connector, 17. DC bias line, 18. PIN diode two, 19. Varactor diode one, 20. Varactor diode two, 21. Long metal microstrip line, 22. Short metal microstrip line one, 23. Short metal microstrip line two. Detailed Implementation

[0042] Example 1

[0043] See Figures 1-3 A linearly polarized in-band scattering reconfigurable divergence time-division controlled array antenna includes 4×4 antenna elements and a 1-to-16 power divider 15. The antenna elements are connected to the 1-to-16 power divider 15. Each antenna element includes, from top to bottom, a radiating patch 1, a dielectric substrate 2, a radiating patch 3, a dielectric substrate 4, a feed coupling stub 5, a feed metal pillar 6, a dielectric substrate 7, a perforated metal ground plane 8, and a dielectric substrate 9. A pin is provided at the bottom of the dielectric substrate 9. The circuit consists of a first tube 11, a second PIN tube 18, a power supply transmission line 10, a DC bias 14, a reflective phase shifter 12, and a low-pass filter 13. The DC bias 14 is connected to the reflective phase shifter 12 and the power supply transmission line 10 through the low-pass filter 13. The reflective phase shifter 12 is equipped with a varactor diode 19 and a varactor diode 20. The power supply metal pillar 6 passes through a dielectric substrate 7, a perforated metal ground plate 8, and a dielectric substrate 9 in sequence and is connected to the power supply transmission line 10.

[0044] This embodiment is the most basic implementation method. Compared with the prior art, it realizes dynamic switching between radiation and scattering states within the same antenna aperture as needed, which can ensure the normal radiation efficiency of the antenna and effectively improve the reconfigurability of antenna scattering.

[0045] Example 2

[0046] See Figures 1-3A linearly polarized in-band scattering reconfigurable divergence time-division controlled array antenna includes 4×4 antenna elements and a 1-to-16 power divider 15. The antenna elements are connected to the 1-to-16 power divider 15. Each antenna element includes, from top to bottom, a radiating patch 1, a dielectric substrate 2, a radiating patch 3, a dielectric substrate 4, a feed coupling stub 5, a feed metal pillar 6, a dielectric substrate 7, a perforated metal ground plane 8, and a dielectric substrate 9. A pin is provided at the bottom of the dielectric substrate 9. The circuit consists of a first tube 11, a second PIN tube 18, a power supply transmission line 10, a DC bias 14, a reflective phase shifter 12, and a low-pass filter 13. The DC bias 14 is connected to the reflective phase shifter 12 and the power supply transmission line 10 through the low-pass filter 13. The reflective phase shifter 12 is equipped with a varactor diode 19 and a varactor diode 20. The power supply metal pillar 6 passes through a dielectric substrate 7, a perforated metal ground plate 8, and a dielectric substrate 9 in sequence and is connected to the power supply transmission line 10.

[0047] The reflective phase shifter 12 includes a long metal microstrip line 21, a short metal microstrip line 22, and a short metal microstrip line 23. The positive terminal of a varactor diode 19 is connected to the short metal microstrip line 22, the negative terminal of the varactor diode 19 is connected to the long metal microstrip line 21, the positive terminal of a varactor diode 20 is connected to the short metal microstrip line 23, and the negative terminal of a varactor diode 20 is connected to the long metal microstrip line 21.

[0048] This embodiment is another preferred implementation. The reflective phase shifter 12 includes a long metal microstrip line 21, a short metal microstrip line 22, and a short metal microstrip line 23. The positive terminal of the varactor diode 19 is connected to the short metal microstrip line 22, and the negative terminal of the varactor diode 19 is connected to the long metal microstrip line 21. The positive terminal of the varactor diode 20 is connected to the short metal microstrip line 23, and the negative terminal of the varactor diode 20 is connected to the long metal microstrip line 21. Through a shared long metal microstrip line 21 and two short metal microstrip lines, combined with two varactor diodes, a balanced reflective circuit is formed, which can provide a stable and adjustable phase shift over a wide frequency band. By independently controlling the capacitance values ​​of the two varactor diodes, the phase of the reflected signal can be precisely controlled, which is beneficial for the flexible control of the antenna scattering beam.

[0049] Example 3

[0050] See Figures 1-3A linearly polarized in-band scattering reconfigurable divergence time-division controlled array antenna includes 4×4 antenna elements and a 1-to-16 power divider 15. The antenna elements are connected to the 1-to-16 power divider 15. Each antenna element includes, from top to bottom, a radiating patch 1, a dielectric substrate 2, a radiating patch 3, a dielectric substrate 4, a feed coupling stub 5, a feed metal pillar 6, a dielectric substrate 7, a perforated metal ground plane 8, and a dielectric substrate 9. A pin is provided at the bottom of the dielectric substrate 9. The circuit consists of a first tube 11, a second PIN tube 18, a power supply transmission line 10, a DC bias 14, a reflective phase shifter 12, and a low-pass filter 13. The DC bias 14 is connected to the reflective phase shifter 12 and the power supply transmission line 10 through the low-pass filter 13. The reflective phase shifter 12 is equipped with a varactor diode 19 and a varactor diode 20. The power supply metal pillar 6 passes through a dielectric substrate 7, a perforated metal ground plate 8, and a dielectric substrate 9 in sequence and is connected to the power supply transmission line 10.

[0051] The reflective phase shifter 12 includes a long metal microstrip line 21, a short metal microstrip line 22, and a short metal microstrip line 23. The positive terminal of a varactor diode 19 is connected to the short metal microstrip line 22, the negative terminal of the varactor diode 19 is connected to the long metal microstrip line 21, the positive terminal of a varactor diode 20 is connected to the short metal microstrip line 23, and the negative terminal of a varactor diode 20 is connected to the long metal microstrip line 21.

[0052] The size of radiation patch 1 is smaller than that of radiation patch 3.

[0053] The PIN tube 11 is placed parallel to the power transmission line 10, dividing the power transmission line 10 into two parts. One end of the power transmission line 10 is connected to the power metal post 6, and the other end of the power transmission line 10 is close to the radiation port.

[0054] The second PIN tube 18 is placed perpendicular to the power supply transmission line 10. One end of the second PIN tube 18 is connected to the power supply transmission line 10 connected to the power supply metal post 6, and the other end of the second PIN tube 18 is connected to the reflective phase shifter 12.

[0055] This embodiment is another preferred implementation. The size of radiating patch 1 is smaller than that of radiating patch 3. This asymmetrical stacked structure broadens the impedance bandwidth of the antenna. The smaller upper radiating patch 1 and the larger lower radiating patch 3 work together to excite multiple adjacent resonant modes and merge them, thereby enabling the antenna to maintain good matching performance over a wider frequency range.

[0056] Example 4

[0057] See Figures 1-3A linearly polarized in-band scattering reconfigurable divergence time-division controlled array antenna includes 4×4 antenna elements and a 1-to-16 power divider 15. The antenna elements are connected to the 1-to-16 power divider 15. Each antenna element includes, from top to bottom, a radiating patch 1, a dielectric substrate 2, a radiating patch 3, a dielectric substrate 4, a feed coupling stub 5, a feed metal pillar 6, a dielectric substrate 7, a perforated metal ground plane 8, and a dielectric substrate 9. A pin is provided at the bottom of the dielectric substrate 9. The circuit consists of a first tube 11, a second PIN tube 18, a power supply transmission line 10, a DC bias 14, a reflective phase shifter 12, and a low-pass filter 13. The DC bias 14 is connected to the reflective phase shifter 12 and the power supply transmission line 10 through the low-pass filter 13. The reflective phase shifter 12 is equipped with a varactor diode 19 and a varactor diode 20. The power supply metal pillar 6 passes through a dielectric substrate 7, a perforated metal ground plate 8, and a dielectric substrate 9 in sequence and is connected to the power supply transmission line 10.

[0058] The reflective phase shifter 12 includes a long metal microstrip line 21, a short metal microstrip line 22, and a short metal microstrip line 23. The positive terminal of a varactor diode 19 is connected to the short metal microstrip line 22, the negative terminal of the varactor diode 19 is connected to the long metal microstrip line 21, the positive terminal of a varactor diode 20 is connected to the short metal microstrip line 23, and the negative terminal of a varactor diode 20 is connected to the long metal microstrip line 21.

[0059] The size of radiation patch 1 is smaller than that of radiation patch 3.

[0060] The PIN tube 11 is placed parallel to the power transmission line 10, dividing the power transmission line 10 into two parts. One end of the power transmission line 10 is connected to the power metal post 6, and the other end of the power transmission line 10 is close to the radiation port.

[0061] The second PIN tube 18 is placed perpendicular to the power supply transmission line 10. One end of the second PIN tube 18 is connected to the power supply transmission line 10 connected to the power supply metal post 6, and the other end of the second PIN tube 18 is connected to the reflective phase shifter 12.

[0062] The negative terminal of the PIN diode 11 is located at one end of the feed transmission line 10 connected to the feed metal post 6, and the positive terminal of the PIN diode 11 is located at one end of the feed transmission line 10 away from the feed metal post 6.

[0063] The negative terminal of the second PIN diode 18 is connected to the reflective phase shifter 12, and the positive terminal of the second PIN diode 18 is connected to one end of the feed transmission line 10 connected to the feed metal post 6.

[0064] This embodiment is another preferred implementation. By changing the reflection phase of the antenna mode term scattering field through a varactor diode, it has a continuous phase change of 360°, which improves the reconfigurability of scattering control.

[0065] The antenna's function can be switched and its scattering characteristics can be reconfigured as needed simply by controlling the DC bias voltage, providing flexible control.

[0066] By using a dual-PIN diode on the feed transmission line 10 to switch between radiation and scattering states, the scattering control section does not affect the radiation performance during radiation. Radiation and scattering are applied with the same aperture and structure, requiring no additional cladding structure and not affecting the normal radiation of the antenna.

[0067] Example 5

[0068] See Figures 1-3 A linearly polarized in-band scattering reconfigurable divergence time-division controlled array antenna includes 4×4 antenna elements and a 1-to-16 power divider 15. The antenna elements are connected to the 1-to-16 power divider 15. Each antenna element includes, from top to bottom, a radiating patch 1, a dielectric substrate 2, a radiating patch 3, a dielectric substrate 4, a feed coupling stub 5, a feed metal pillar 6, a dielectric substrate 7, a perforated metal ground plane 8, and a dielectric substrate 9. A pin is provided at the bottom of the dielectric substrate 9. The circuit consists of a first tube 11, a second PIN tube 18, a power supply transmission line 10, a DC bias 14, a reflective phase shifter 12, and a low-pass filter 13. The DC bias 14 is connected to the reflective phase shifter 12 and the power supply transmission line 10 through the low-pass filter 13. The reflective phase shifter 12 is equipped with a varactor diode 19 and a varactor diode 20. The power supply metal pillar 6 passes through a dielectric substrate 7, a perforated metal ground plate 8, and a dielectric substrate 9 in sequence and is connected to the power supply transmission line 10.

[0069] The reflective phase shifter 12 includes a long metal microstrip line 21, a short metal microstrip line 22, and a short metal microstrip line 23. The positive terminal of a varactor diode 19 is connected to the short metal microstrip line 22, the negative terminal of the varactor diode 19 is connected to the long metal microstrip line 21, the positive terminal of a varactor diode 20 is connected to the short metal microstrip line 23, and the negative terminal of a varactor diode 20 is connected to the long metal microstrip line 21.

[0070] The size of radiation patch 1 is smaller than that of radiation patch 3.

[0071] The PIN tube 11 is placed parallel to the power transmission line 10, dividing the power transmission line 10 into two parts. One end of the power transmission line 10 is connected to the power metal post 6, and the other end of the power transmission line 10 is close to the radiation port.

[0072] The second PIN tube 18 is placed perpendicular to the power supply transmission line 10. One end of the second PIN tube 18 is connected to the power supply transmission line 10 connected to the power supply metal post 6, and the other end of the second PIN tube 18 is connected to the reflective phase shifter 12.

[0073] The negative terminal of the PIN diode 11 is located at one end of the feed transmission line 10 connected to the feed metal post 6, and the positive terminal of the PIN diode 11 is located at one end of the feed transmission line 10 away from the feed metal post 6.

[0074] The negative terminal of the second PIN diode 18 is connected to the reflective phase shifter 12, and the positive terminal of the second PIN diode 18 is connected to one end of the feed transmission line 10 connected to the feed metal post 6.

[0075] The dielectric constants of dielectric substrate 2, dielectric substrate 4, and dielectric substrate 7 are all 2.65, and the dielectric constant of dielectric substrate 9 is 6.15.

[0076] Both the first radiation patch and the second radiation patch are rectangular patches.

[0077] This embodiment is the best implementation method. The reflective phase shifter 12 with continuous linear phase change realizes the continuous linear change of the same polarization reflection phase of the antenna element in the band by 360°. For the case of vertical incidence of electromagnetic waves, it can realize the reduction of the single-station RCS, that is, the single-station radar cross section and the ability to deflect the scattered beam by ±45°.

[0078] The dielectric constants of dielectric substrate 1 (2), dielectric substrate 2 (4), and dielectric substrate 3 (7) are all 2.65, while the dielectric constant of dielectric substrate 4 (9) is 6.15. The use of lower dielectric constants for dielectric substrates 1 (2), 2 (4), and 3 (7) helps to reduce the confinement of surface waves, improve the radiation efficiency of the antenna, and broaden the beamwidth. The use of higher dielectric constants for dielectric substrate 4 (9) helps to achieve miniaturization and compact design of the antenna elements and the entire array. Through the design of using a mixture of high and low dielectric constants, an optimal balance is achieved between performance and size.

[0079] The working principle of this invention is as follows:

[0080] The antenna is a double-layer stacked microstrip antenna, consisting of four dielectric layers: three substrates with a dielectric constant of 2.65 and one substrate with a dielectric constant of 6.15, from top to bottom. The metal structure from top to bottom consists of: radiating patch 1, radiating patch 2, feed coupling stub 5, perforated metal ground plane 8, reflective phase shifter 12, low-pass filter 13, feed transmission line 10, and DC biaser 14. The feed coupling stub 5 and the feed transmission line 10 are connected by metallized vias. PIN diode 11 and PIN diode 2 18 are connected to the feed transmission line 10. By controlling the on / off state of these two PIN diodes, the radiation and scattering modes are switched on the same antenna. In scattering mode, the reflective phase shifter 12 achieves multi-functional scattering control.

[0081] The antenna is arrayed in a 4×4 configuration. The FPGA control system determines the state of the PIN diodes via DC bias control: in radiation mode, PIN diode 11 is on and PIN diode 18 is off, while in scattering mode, PIN diode 11 is off and PIN diode 18 is on. In scattering mode, the reverse bias voltage of the varactor diode of the reflective phase shifter 12 is adjusted to dynamically control the scattering field of the antenna mode. In radiation mode, the disconnection of PIN diode 18 means that the structure of the reflective phase shifter 12 does not affect the antenna's radiation.

[0082] The antenna achieves time-division reconfiguration of radiation and scattering states through coordinated control of the PIN diode and varactor diode. In the radiation state, PIN diode 11 is turned on and PIN diode 18 is turned off, allowing the RF signal to be coupled to the double-layer radiating patch via the feed transmission line 10 and the feed metal pillar 6, forming normal radiation. In the scattering state, PIN diode 11 is turned off and PIN diode 18 is turned on, connecting the antenna element to the reflective phase shifter 12. At this time, the antenna, as a passive structure, is illuminated by radar waves. The current excited by the incident wave is reflected by the reflective phase shifter 12. By independently adjusting the bias voltage of the two varactor diodes, the phase of the reflected signal can be continuously changed, thereby reconstructing the antenna's scattering beam and reducing in-band scattering. The DC biaser 14 and the low-pass filter 13 ensure isolation between the control circuit and the RF signal.

[0083] By switching between radiation and scattering modes, in scattering mode, continuous 360° phase adjustment of the element reflection can be achieved simply by changing the DC bias voltage of the varactor diode, improving the reconfigurability of antenna scattering. In radiation mode, the scattering adjustment structure does not affect the normal radiation of the antenna. Radiation and scattering are used in a time-division multiplexing manner with the same aperture, eliminating the need for additional cladding structures and maintaining the normal radiation efficiency of the antenna.

[0084] The low-pass filter 13 consists of two 5nH inductors and a 100nF parallel capacitor. One end of the inductor-loaded low-pass filter 13 is connected to positions one, two, and three of the feed transmission line 10 and the reflective phase shifter 12. At positions one and three, the other end of the low-pass filter 13 is loaded with a DC square metal plate. At position three, the DC square metal plate is connected to V3, which is a DC voltage. At position two, the other end of the low-pass filter 13 is loaded with a metal shorting post connected to the perforated metal ground plane 8. A 5pF capacitor is loaded between positions two and three to separate the DC voltages.

[0085] The 4×4 array antenna is connected by a 1-to-16 power divider 15, fed by an SMP RF connector 16 (i.e., a miniature RF coaxial connector), and mounted on the lower surface of dielectric substrate 49. At the location of the 1-to-16 power divider 15, low-pass filters 13 are placed vertically along microstrip lines and connected to DC biasers 14 via V4, where V4 is a DC voltage. A 5pF capacitor is applied between the location of the 1-to-16 power divider 15 and the SMP RF connector 16.

[0086] The DC bias square metal pieces at each antenna location are connected by a narrow DC bias line 17, and a DC bias square metal piece is set at location five to connect to V1, where V1 is a DC voltage.

[0087] The switching between radiation and scattering modes is achieved by switching PIN tube 11 and PIN tube 2 18 on and off. In scattering mode, a continuously linearly varying reflection phase within a 360° range can be obtained through the reflective phase shifter 12.

[0088] The specific implementation method of radiation and scattering modes includes the following steps:

[0089] When the bias voltage V1 is grounded and V4 is connected to a 1.4V DC voltage source, the antenna is in a radiating state.

[0090] When the bias voltage V1 is connected to a 1.4V DC voltage source and V4 is grounded, the antenna is in a scattering state. At this time, by adjusting the bias voltage V3, the reflection phase of the antenna element can be adjusted, thereby changing the reflection phase of the antenna element in the array, thus realizing active control of the scattered beam and reduction of the single-station radar cross section.

[0091] The effects of this invention will be further explained below with reference to simulation experiments:

[0092] Simulation of the radiation characteristics of the antenna element:

[0093] When bias voltage V1 is connected to the reference ground voltage of 0V and V4 is connected to a 1.4V voltage source, the antenna is in a radiating state. At this time, PIN diode 11 is equivalent to a series circuit of resistor R=5.2Ω and inductor L=30pH, and PIN diode 18 is equivalent to a series circuit of inductor L=30pH and capacitor 25fF. Figure 4 It can be seen that the antenna has good gain.

[0094] Simulation of the reflection characteristics of the antenna element:

[0095] When bias voltage V1 is connected to a 1.4V voltage source and V4 is connected to a reference ground voltage of 0V, the antenna is in a scattering state. At this time, PIN diode 11 is equivalent to a series circuit of inductor L=30pH and capacitor L=25fF, and PIN diode 18 is equivalent to a series circuit of resistor R=5.2Ω and inductor L=30pH. Figure 5It can be seen that the capacitance of the varactor diode in the reflective phase shifter 12 changes with voltage. As the bias voltage V4 is adjusted, the capacitance varies within the range of 0.15pF-1.3pF in the simulation. The reflection amplitude of the antenna element is as follows... Figure 6 As shown, the reflection phase of the antenna element is as follows: Figure 7 As shown, the average difference in reflection amplitude is less than 2dB within the antenna's radiation operating bandwidth, and the reflection phase variation range is 360°.

[0096] The radiation performance of the array antenna was simulated, and the results are as follows: Figure 8 As shown:

[0097] The disconnection of PIN diode 18 ensures that the reflective phase shifter 12 does not affect the normal radiation of the antenna.

[0098] Simulations were performed on the scattering reduction performance of the array antenna, and the results are as follows: Figure 9 As shown:

[0099] Under horizontally polarized vertical incidence, by optimizing the DC bias voltage V3 of each antenna element, the array antenna achieves at least a 6 dB reduction in radar cross section in the 4.3-5.6 GHz band compared to the reference state, with a peak radar cross section reduction of 25 dB at 4.6 GHz and a peak radar cross section reduction of 27 dB at 5 GHz.

[0100] The performance of the scattered beam control of the array antenna was simulated, and the results are as follows: Figure 10 Bistatic RCS scattering beam deflection, i.e., bistatic radar cross section scattering beam deflection, is shown as follows:

[0101] Under horizontally polarized vertical incidence, by combining the DC bias voltage V3 of each antenna element with the reflection phase selection, the array antenna scattering beam can be deflected from 0° to 15°, 30°, 40° and 45° at 5GHz, with the ability to deflect the scattering beam by ±45°.

Claims

1. A linearly polarized in-band scattering reconfigurable divergence time-division modulated array antenna, comprising 4×4 antenna elements and a 1-to-16 power divider (15), wherein the antenna elements are connected to the 1-to-16 power divider (15), characterized in that: The antenna unit includes, from top to bottom, a radiating patch 1 (1), a dielectric substrate 1 (2), a radiating patch 2 (3), a dielectric substrate 2 (4), a feed coupling stub (5), a feed metal pillar (6), a dielectric substrate 3 (7), a perforated metal ground plane (8), and a dielectric substrate 4 (9). The bottom of the dielectric substrate 4 (9) is provided with a PIN diode 1 (11), a PIN diode 2 (18), a feed transmission line (10), a DC bias (14), a reflective phase shifter (12), and a low-pass filter (13). The DC bias (14) is connected to the reflective phase shifter (12) and the feed transmission line (10) through the low-pass filter (13). The reflective phase shifter (12) is provided with a varactor diode 1 (19) and a varactor diode 2 (20). The feed metal pillar (6) passes through the dielectric substrate 3 (7), the perforated metal ground plane (8), and the dielectric substrate 4 (9) in sequence and is connected to the feed transmission line (10). The reflective phase shifter (12) includes a long metal microstrip line (21), a short metal microstrip line one (22) and a short metal microstrip line two (23). The positive terminal of the varactor diode one (19) is connected to the short metal microstrip line one (22), the negative terminal of the varactor diode one (19) is connected to the long metal microstrip line (21), the positive terminal of the varactor diode two (20) is connected to the short metal microstrip line two (23), and the negative terminal of the varactor diode two (20) is connected to the long metal microstrip line (21).

2. The linearly polarized in-band scattering reconfigurable divergence time-division modulated array antenna according to claim 1, characterized in that: The size of the first radiation patch (1) is smaller than that of the second radiation patch (3).

3. The linearly polarized in-band scattering reconfigurable divergence time-division modulated array antenna according to claim 1, characterized in that: The PIN tube (11) is placed parallel to the power transmission line (10) to divide the power transmission line (10) into two parts. One end of the power transmission line (10) is connected to the power metal post (6), and the other end of the power transmission line (10) is close to the radiation port.

4. The linearly polarized in-band scattering reconfigurable divergence time-division modulated array antenna according to claim 1, characterized in that: The second PIN tube (18) is placed perpendicular to the power supply transmission line (10). One end of the second PIN tube (18) is connected to the power supply transmission line (10) connected to the power supply metal column (6), and the other end of the second PIN tube (18) is connected to the reflective phase shifter (12).

5. The linearly polarized in-band scattering reconfigurable divergence time-division modulated array antenna according to claim 1, characterized in that: The negative terminal of the PIN tube (11) is located at one end of the feed transmission line (10) connected to the feed metal post (6), and the positive terminal of the PIN tube (11) is located at one end of the feed transmission line (10) away from the feed metal post (6).

6. The linearly polarized in-band scattering reconfigurable divergence time-division modulated array antenna according to claim 1, characterized in that: The negative terminal of the second PIN tube (18) is connected to the reflective phase shifter (12), and the positive terminal of the second PIN tube (18) is connected to one end of the feed transmission line (10) connected to the feed metal column (6).

7. The linearly polarized in-band scattering reconfigurable divergence time-division modulated array antenna according to claim 1, characterized in that: The dielectric constants of dielectric substrate one (2), dielectric substrate two (4) and dielectric substrate three (7) are all 2.65, and the dielectric constant of dielectric substrate four (9) is 6.

15.

8. The linearly polarized in-band scattering reconfigurable divergence time-division modulated array antenna according to claim 1, characterized in that: Both the first radiation patch (1) and the second radiation patch (3) are rectangular patches.

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