Circularly polarized dielectric resonator two-dimensional beam scanning phased-array antenna based on liquid crystal

Abstract

The invention discloses a circularly polarized dielectric resonator two-dimensional beam scanning phased-array antenna based on liquid crystal, and belongs to the technical field of microwave antennas. The antenna comprises an elliptic cylindrical dielectric resonator radiation structure, a sequential rotation feed network and a liquid crystal phase shifter structure based on a glass plate, wherein the elliptic cylindrical dielectric resonator radiation structure and the sequential rotation feed network are arranged on a flexible printed circuit board (FPC); the radiation structure and the feed network which are arranged on the FPC comprise a radiation unit, an FPC layer and a feed network; the liquid crystal phase shifter comprises a glass dielectric substrate, a liquid crystal layer, an inverted spiral microstrip line and a bias network; the elliptic cylindrical dielectric resonator radiation structure realizes wide impedance bandwidth and wide axial ratio bandwidth; the antenna array also uses a sequential rotation method, the axial ratio characteristic of the phased-array antenna is further improved, and the coupling feed structure is simplified by using the design that the L-shaped microstrip line is connected with the inverted spiral microstrip line after sequential rotation.

Description

Technical Field

[0001] The invention belongs to the technical field of microwave antennas, and in particular relates to a two-dimensional beam scanning phased array antenna based on a circularly polarized dielectric resonator of liquid crystal. Background Art

[0002] With the accelerated development of the global information industry, the demand for satellite communication systems in the fields of national defense, commerce, and people's livelihood is increasing. All industries have increased their investment in satellite Internet technology, hoping to build a satellite Internet system with global coverage. Among them, array antennas are widely used because of their advantages such as high gain and narrow beam. Conventional array antennas can only radiate directional beams, but after adding electrical adjustment devices such as phase shifters to the feed port of each unit, spatial scanning of the radiated beam can be achieved. Such antennas are called phased array antennas. For traditional active phased arrays, although their performance is excellent, there are also some shortcomings that limit the application scenarios, such as high cost, bulky size (high profile), difficult heat dissipation, and high engineering difficulty. Phased array antennas based on liquid crystal phase shifting technology have many advantages such as low cost, lightweight, low profile, low power consumption, high control flexibility, and conducive to the realization of intelligent reconfigurable characteristics. However, the current performance of liquid crystal phased array antennas, such as working bandwidth and scanning angle range, is still a certain distance away from practical requirements.

[0003] The prior art "Liquid crystal based phased array antenna with improved beamscanning capability" discloses a liquid crystal-based dielectric resonator phased array antenna, which replaces the radiating element from the traditional microstrip patch with a dielectric resonator. When the beam scanning range is ±30°, the gain drops by only 1.5dB, but it can only achieve one-dimensional beam scanning, does not achieve circular polarization, and the process of placing the dielectric resonator on the glass substrate is complicated. The prior art "30GHz liquid crystal phased array" discloses a 4*4 liquid crystal phased array operating at 30GHz, where each of the four antennas is controlled by a liquid crystal phase shifter. Therefore, only one-dimensional beam scanning can be achieved, and the scanning range is ±30°. The prior art "Research on microwave millimeter-wave microstrip phased array antenna based on liquid crystal phase shifting technology" discloses an electrically controlled microstrip patch phased array antenna based on liquid crystal delay line phase shifting, with a beam scanning range of (-50° to 50°) and a normal gain of 22.85dB, achieving two-dimensional beam scanning, but the axial ratio bandwidth is only about 300MHz. How to design a broadband liquid crystal phased array antenna is a difficult point. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a two-dimensional beam scanning phased array antenna based on a circularly polarized dielectric resonator of liquid crystal, which improves the impedance bandwidth and axial ratio bandwidth performance of the antenna on the basis of the liquid crystal phased array antenna architecture, and simplifies the coupled feeding structure after sequential rotation.

[0005] The technical problem proposed by the present invention is solved in this way:

[0006] A liquid crystal-based circularly polarized dielectric resonator two-dimensional beam scanning phased array antenna, comprising a dielectric resonator radiation unit layer 1, a flexible printed circuit board 2, a feed network 3, a tape 4, a first glass substrate 5, a ground plate 6, a liquid crystal layer 7, an inverted spiral microstrip line phase shifter layer 8, a sealing frame 9 and a second glass substrate 10;

[0007] The dielectric resonator radiation unit layer 1 is located on the upper surface of the flexible printed circuit board 2, and is composed of dielectric resonators 101 arranged in a two-dimensional periodic manner of 2N×2N, where N is a positive integer; the feeding network 3 is located on the lower surface of the flexible printed circuit board 2, and the feeding network 3 is a two-dimensional periodic arrangement of dielectric resonators 101. N+1 T-shaped microstrip power divider; the ground plate 6 is a copper metal plate, which covers the lower surface of the first glass substrate 5 and covers the area corresponding to the position of the dielectric resonator radiation unit 1; the inverted spiral microstrip line phase shifter layer 8 is located on the upper surface of the second glass substrate 9, and is composed of an inverted spiral microstrip line 801 arranged in a two-dimensional manner of 2N×2N; the tape 4 is applied to the edges around the lower surface of the flexible printed circuit board 2 and bonded to the upper surface of the first glass substrate 5 to form a cavity in the middle; the upper surface of the second glass substrate 10 is connected to the lower surface of the first glass substrate 5 through a sealing frame 9 to form a sealed box body, and the interior is filled with liquid crystal as a liquid crystal layer 7; the ground plate 6 has a coupling gap at the tail of the feeding network 3 and the inverted spiral microstrip line 801.

[0008] Furthermore, the dielectric resonator 101 is in the shape of an elliptical cylinder for realizing circularly polarized radiation; the 2N×2N dielectric resonator 101 is divided into a plurality of 2×2 subarrays; for each subarray, the upper left corner point is recorded as the origin, d is the period of the dielectric resonator 101, the dielectric resonator 101 located at the upper left position forms an angle of 45° with the edge of the flexible printed circuit board 2, and the dielectric resonators 101 at the upper right position, the lower right position and the lower left position in the 2×2 subarray are respectively obtained by rotating the dielectric resonator 101 at the upper left position clockwise by 90°, 180° and 270° with (d, d) as the center; the 2×2 subarray is extended with the subarray period 2d to form a dielectric resonator radiation unit layer 1.

[0009] Furthermore, the feed network 3 is an N+1-stage one-to-two T-junction microstrip power divider structure, which is a one-to-two N+1The output microstrip line of each one-to-two T-junction microstrip power divider is of the same length, the characteristic impedance of the microstrip line at the input and output ends is 100Ω, and a 1 / 4 waveguide wavelength impedance transformer is used at the T-junction branch for impedance transformation; the input microstrip line of the first one-to-two T-junction microstrip power divider is cascaded with an impedance matching microstrip line as the input end of the feed network 3; the ground plate 6 is provided with a first coupling gap perpendicular to the output microstrip line of the N+1th one-to-two T-junction microstrip power divider in the feed network 3.

[0010] Furthermore, the inverted spiral microstrip line phase shifter layer 8 includes a bias network and 2N×2N inverted spiral microstrip lines 801; the 2N×2N inverted spiral microstrip lines 801 are divided into a plurality of 2×2 inverted spiral microstrip line groups; for each inverted spiral microstrip line group, the upper left corner point is taken as the origin, and the inverted spiral microstrip lines 801 at the upper right position, the lower right position and the lower left position are respectively obtained by rotating the inverted spiral microstrip line 801 at the upper left position clockwise by 90°, 180° and 270° with (d, d) as the center; for the inverted spiral microstrip line 801 at the upper left position, the length is 4λ g ~6λ g The microstrip line is rotated clockwise, λ g is the waveguide wavelength; the starting end of the inverted spiral microstrip line 801 is connected to an L-shaped microstrip line, and the two L-shaped microstrip lines adjacent in the horizontal direction are symmetrically arranged along the vertical axis, and the two L-shaped microstrip lines adjacent in the vertical direction are symmetrically arranged along the horizontal axis; the ground plate 6 has a second coupling gap perpendicular to the inverted spiral microstrip line 801 at the end position; the bias network is a 2N×2N AC bias line 802, which is connected to the corresponding inverted spiral microstrip line 801 respectively; the AC bias line 802 is provided with a length of λ g An open transmission line with a length of / 4 is used as a radio frequency isolation structure. One end of the open transmission line is connected to the AC bias line 802 at a distance λ from the connection point of the inverted spiral microstrip line 801. g / 4, and the other end is open; the control circuit is connected to the 2N×2N inverted spiral microstrip line 801 through the 2N×2N AC bias line 802, and is used to control the bias voltage of the inverted spiral microstrip line 801. The control circuit is implemented by FPGA.

[0011] Furthermore, N=2.

[0012] Furthermore, the dielectric constant of the glass substrates used by both the first glass substrate 5 and the second glass substrate 9 is 5.8.

[0013] Furthermore, the relative dielectric constant of the liquid crystal used in the liquid crystal layer 7 is adjusted in the range of 2.5 to 3.52.

[0014] Furthermore, the liquid crystal layer 7 undergoes an alignment treatment, and when no bias voltage is applied, the liquid crystal molecules point in the same direction, and the liquid crystal material has a minimum dielectric constant; when a bias voltage is applied to the inverted spiral microstrip line 801 through the bias line, the liquid crystal molecules are deflected, the dielectric constant of the liquid crystal material changes, and the phase shift amount of the equivalent phase shifter of the corresponding inverted spiral microstrip line 801 changes, thereby achieving the adjustment of the phase shift amount.

[0015] Furthermore, initial polarization phases of 0°, 90°, 180° and 270° are configured for the 2×2 subarray; the scanning phase required for each inverted spiral microstrip line 801 is calculated according to the planar phased array beam pointing principle and the required antenna beam azimuth angle, the scanning phase and the initial polarization phase are superimposed, and the bias voltage value corresponding to the liquid crystal is calculated, and the bias voltage is applied to each inverted spiral microstrip line 801 equivalent phase shifter through the bias network.

[0016] The beneficial effects of the present invention are:

[0017] The antenna of the present invention adopts a dielectric resonator radiation structure with a perturbation structure for the first time in the field of liquid crystal phased array antennas. The dielectric resonator antenna is a radiator composed of a low-loss microwave dielectric material, radiates through the entire resonator surface except the ground, has no conductor and surface wave losses, has a wider impedance bandwidth, axial ratio bandwidth, and higher radiation efficiency. The dielectric resonator radiation structure is located on the upper surface of the flexible printed circuit board FPC to avoid adhesion of the dielectric resonator unit on the glass, making the processing feasible and stable.

[0018] The antenna of the present invention realizes broadband scanning through a circularly polarized antenna array arrangement based on a sequential rotation method. First, four antenna units are arranged into a 2×2 subarray in a clockwise or counterclockwise order, and then the four antenna units are given feeding phases of 0°, 90°, 180° and 270°. The sequential rotation feeding method utilizes the vector superposition characteristics of electromagnetic waves. By changing the antenna placement and performing phase compensation, the antenna radiation performance and polarization performance are optimized. The 2×2 circularly polarized subarray based on the sequential rotation method is expanded to 2N×2N according to the array formation method of extending the subarray period. The above array 2N×2N can achieve wider circular polarization performance.

[0019] The antenna of the present invention adjusts the liquid crystal dielectric constant of the phase shifter unit to achieve feeding phases of 0°, 90°, 180° and 270° for a 2×2 subarray based on a sequential rotation method, utilizes the continuous phase modulation property of liquid crystal, avoids designing a complex feeding structure on the feeding network, simplifies the structure and required length of the feeding network, thereby reducing the transmission loss of the feeding network and achieving the feeding phase required for the 2×2 subarray based on the sequential rotation method. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a front view of the liquid crystal phased array antenna structure of the present invention;

[0021] Figure 2 It is a schematic structural diagram of the upper surface of the flexible printed circuit board in the liquid crystal phased array antenna of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of the feeding network in the liquid crystal phased array antenna of the present invention;

[0023] Figure 4 A schematic diagram of the position relationship of the coupling slots on the ground plate of the liquid crystal phased array antenna of the present invention;

[0024] Figure 5 It is a schematic structural diagram of an inverted spiral microstrip line phase shifter layer in the liquid crystal phased array antenna of the present invention;

[0025] Figure 6 is a graph of S11 of the liquid crystal phased array antenna described in the embodiment;

[0026] Figure 7 1 is a diagram showing the axis alignment versus frequency of the liquid crystal phased array antenna described in the embodiment. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0028] This embodiment provides a two-dimensional beam scanning phased array antenna based on a circularly polarized dielectric resonator of liquid crystal, such as Figure 1 As shown, it includes a dielectric resonator radiation unit layer 1, a flexible printed circuit board 2, a feeding network 3, a tape 4, a first glass substrate 5, a ground plate 6, a liquid crystal layer 7, an inverted spiral microstrip line phase shifter layer 8, a sealing frame 9 and a second glass substrate 10;

[0029] The dielectric resonator radiation unit layer 1 is located on the upper surface of the flexible printed circuit board 2, and is composed of dielectric resonators 101 arranged in a two-dimensional periodic manner of 2N×2N, where N is a positive integer; the feeding network 3 is located on the lower surface of the flexible printed circuit board 2, and the feeding network 3 is a two-dimensional periodic arrangement of dielectric resonators 101. N+1T-shaped microstrip power divider; the ground plate 6 is a copper metal plate, which covers the lower surface of the first glass substrate 5 and covers the area corresponding to the position of the dielectric resonator radiation unit 1; the inverted spiral microstrip line phase shifter layer 8 is located on the upper surface of the second glass substrate 9, and is composed of an inverted spiral microstrip line 801 arranged in a two-dimensional manner of 2N×2N; the tape 4 is applied to the edges around the lower surface of the flexible printed circuit board 2 and bonded to the upper surface of the first glass substrate 5 to form a cavity in the middle; the upper surface of the second glass substrate 10 is connected to the lower surface of the first glass substrate 5 through a sealing frame 9 to form a sealed box body, and the interior is filled with liquid crystal as a liquid crystal layer 7; the ground plate 6 has a coupling gap at the tail of the feeding network 3 and the inverted spiral microstrip line 801.

[0030] In this embodiment, the dielectric resonator 101 is in the shape of an elliptical cylinder. Figure 2 As shown, for realizing circular polarization radiation, a material with high dielectric constant (relative dielectric constant greater than 10) is selected (e.g. Rogers RO3010). The 2N×2N dielectric resonator 101 is divided into several 2×2 subarrays; for each subarray, the upper left corner is taken as the origin, d is the period of the dielectric resonator 101, the dielectric resonator 101 located at the upper left position forms an angle of 45° with the edge of the flexible printed circuit board 2, and the dielectric resonators 101 at the upper right position, the lower right position and the lower left position in the 2×2 subarray are respectively obtained by rotating the dielectric resonator 101 at the upper left position clockwise by 90°, 180° and 270° with (d, d) as the center; the 2×2 subarray is extended with the subarray period 2d to form the dielectric resonator radiation unit layer 1.

[0031] In this embodiment, Figure 3 As shown, the feeding network 3 is an N+1-level one-to-two T-junction microstrip power divider structure. N+1 The output microstrip line of each one-to-two T-junction microstrip power divider is of the same length, the characteristic impedance of the microstrip line at the input and output ends is 100Ω, and a 1 / 4 waveguide wavelength impedance transformer is used at the T-junction branch for impedance transformation; the input microstrip line of the first one-to-two T-junction microstrip power divider is cascaded with an impedance matching microstrip line as the input end of the feed network 3; the ground plate 6 is provided with a first coupling gap perpendicular to the output microstrip line of the N+1th one-to-two T-junction microstrip power divider in the feed network 3.

[0032] In this embodiment, there are two types of coupling gaps on the floor 6, such as Figure 4 As shown, the two coupling slots have different sizes; for each 2×2 subarray, there are two first coupling slots and four second coupling slots, and the positions of the second coupling slots are obtained by rotating 0, 90°, 180° and 270° respectively with (d, d) as the center.

[0033] In this embodiment, Figure 5 As shown, the inverted spiral microstrip line phase shifter layer 8 includes a bias network and 2N×2N inverted spiral microstrip lines 801; the 2N×2N inverted spiral microstrip lines 801 are divided into a plurality of 2×2 inverted spiral microstrip line groups; for each inverted spiral microstrip line group, the upper left corner point is taken as the origin, and the inverted spiral microstrip lines 801 at the upper right, lower right and lower left positions are respectively obtained by rotating the inverted spiral microstrip line 801 at the upper left position clockwise by 90°, 180° and 270° with (d, d) as the center; for the inverted spiral microstrip line 801 at the upper left position, the inverted spiral microstrip line 801 at the upper left position is obtained by rotating the inverted spiral microstrip line 801 at the upper left position by 4λ in length. g ~6λ g The microstrip line is rotated clockwise, λ g is the waveguide wavelength; the starting end of the inverted spiral microstrip line 801 is connected to an L-shaped microstrip line, and the two L-shaped microstrip lines adjacent in the horizontal direction are symmetrically arranged along the vertical axis, and the two L-shaped microstrip lines adjacent in the vertical direction are symmetrically arranged along the horizontal axis; the ground plate 6 has a second coupling gap perpendicular to the inverted spiral microstrip line 801 at the end position; the bias network is a 2N×2N AC bias line 802, which is connected to the corresponding inverted spiral microstrip line 801 respectively; the AC bias line 802 is provided with a length of λ g An open transmission line with a length of / 4 is used as a radio frequency isolation structure. One end of the open transmission line is connected to the AC bias line 802 at a distance λ from the connection point of the inverted spiral microstrip line 801. g / 4, and the other end is open; the control circuit is connected to the 2N×2N inverted spiral microstrip line 801 through the 2N×2N AC bias line 802, and is used to control the bias voltage of the inverted spiral microstrip line 801. The control circuit is implemented by FPGA.

[0034] In this embodiment, the first glass substrate 5 and the second glass substrate 9 are staggered in the direction of the bias line lead-out, so that the bias pin is exposed to the air, which facilitates binding the bias pin and the soft tape line connected to the FPGA circuit board together.

[0035] In this embodiment, the dielectric constant of the glass substrates used by the first glass substrate 5 and the second glass substrate 9 is 5.8.

[0036] In this embodiment, the relative dielectric constant of the liquid crystal used in the liquid crystal layer 7 is adjusted in the range of 2.5 to 3.52.

[0037] In this embodiment, the liquid crystal layer 7 is subjected to an alignment treatment, and when no bias voltage is applied, the liquid crystal molecules point in the same direction, and the liquid crystal material has a minimum dielectric constant; when a bias voltage is applied to the inverted spiral microstrip line 801 through the bias line, the liquid crystal molecules are deflected, the dielectric constant of the liquid crystal material changes, and the phase shift amount of the equivalent phase shifter of the corresponding inverted spiral microstrip line 801 changes, thereby achieving the adjustment of the phase shift amount.

[0038] In this embodiment, the initial polarization phases of 0°, 90°, 180° and 270° of the 2×2 sub-array based on the sequential rotation method are configured; the scanning phase required for each inverted spiral microstrip line 801 is calculated according to the beam pointing principle of the planar phased array and the required antenna beam azimuth angle, the scanning phase and the initial polarization phase are superimposed, and the bias voltage value corresponding to the liquid crystal is calculated, and the bias voltage is applied to the equivalent phase shifter of each inverted spiral microstrip line 801 through the bias network. This can quickly change the radiation state of each unit and realize two-dimensional continuous dynamic scanning of the beam in the upper half space.

[0039] In this embodiment, N=2, and the liquid crystal phased array antenna adopts a multi-layer slot coupling feeding structure. The RF signal of the output microstrip line of the N+1th level one-to-two T-junction power divider on the feeding network 3 is coupled to the inverted spiral microstrip line 801 for transition through the first coupling slot on the ground plane 6. Then, the phase of the RF signal changes after passing through the inverted spiral microstrip line 801, and then the RF signal of the phase shifter layer can be coupled to the dielectric resonator radiation structure for feeding through the second coupling slot on the ground plane 6.

[0040] The antenna described in this embodiment was simulated using the commercial electromagnetic simulation software CST Studio Suite. The results are as follows: Figure 6 , Figure 7 As shown. Among them, the S11 of the antenna is less than -10dB in the range of 18.8GHz to 24GHz. The axial ratio at 20GHz is about 0.5dB, and the axial ratio bandwidth is 18.85GHz to 21.15GHz. In general, the antenna described in this embodiment has good broadband performance.

[0041] The antenna of the present invention creatively adopts a dielectric resonator radiation structure with a perturbation structure for the first time in the field of liquid crystal phased array antennas. The dielectric resonator antenna is a radiator composed of low-loss microwave dielectric materials, radiates through the entire resonator surface except the ground, and has no conductor and surface wave losses. It has a wide impedance bandwidth, axial ratio bandwidth, and high radiation efficiency. The dielectric resonator radiation structure is located on the upper surface of the FPC to avoid adhesion of the dielectric resonator unit on the glass, making the processing feasible and stable. On the other hand, the radiation structure, feed network and liquid crystal phase shifter are designed and processed separately, and the fault tolerance rate is higher.

[0042] The antenna of the present invention realizes broadband scanning through a circularly polarized antenna array arrangement based on a sequential rotation method. First, four antenna units are arranged into a 2×2 subarray in a clockwise or counterclockwise order, and then the four antenna units are given feeding phases of 0°, 90°, 180° and 270°. The sequential rotation feeding method utilizes the vector superposition characteristics of electromagnetic waves. By changing the antenna placement and performing phase compensation, the antenna radiation performance and polarization performance are optimized. The 2×2 circularly polarized subarray based on the sequential rotation method is expanded to 2N×2N in a periodically extended array mode. The above array 2N×2N can achieve wider circular polarization performance.

[0043] The antenna of the present invention adjusts the liquid crystal dielectric constant of the phase shifter unit to achieve the feeding phases of 0°, 90°, 180° and 270° of the 2×2 subarray based on the sequential rotation method, utilizes the characteristic of liquid crystal that can continuously adjust the phase, avoids designing a complex feeding structure on the feeding network, simplifies the structure and required length of the feeding network, thereby reducing the transmission loss of the feeding network and achieving the feeding phase required by the 2×2 subarray based on the sequential rotation method.

[0044] The above description is only a specific implementation mode of the present invention. Any feature disclosed in this specification, unless otherwise stated, can be replaced by other alternative features that are equivalent or have similar purposes; all the disclosed features, or all the steps in the methods or processes, except for mutually exclusive features and / or steps, can be combined in any way.

Claims

1. A liquid crystal based circularly polarized dielectric resonator two-dimensional beam scanning phased array antenna, characterized in that: It comprises a dielectric resonator radiation unit layer (1), a flexible printed circuit board (2), a feeding network (3), a tape glue (4), a first glass substrate (5), a ground plate (6), a liquid crystal layer (7), an inverted spiral microstrip line phase shifter layer (8), a sealing frame (9) and a second glass substrate (10); The dielectric resonator radiation unit layer (1) is located on the upper surface of the flexible printed circuit board (2), and is composed of dielectric resonators (101) arranged in a two-dimensional periodic pattern of 2N×2N, where N is a positive integer; The feed network (3) is located on the lower surface of the flexible printed circuit board (2). The feed network (3) is a two-way N+1 The invention discloses a T-shaped microstrip power divider; the ground plate (6) is a copper metal plate, which covers the lower surface of the first glass substrate (5) and covers the corresponding position of the dielectric resonator radiation unit (1); the inverted spiral microstrip line phase shifter layer (8) is located on the upper surface of the second glass substrate (9) and is composed of 2N×2N two-dimensionally arranged inverted spiral microstrip lines (801); the tape glue (4) is applied to the edges around the lower surface of the flexible printed circuit board (2) and is bonded to the upper surface of the first glass substrate (5) to form a cavity in the middle; the upper surface of the second glass substrate (10) and the lower surface of the first glass substrate (5) are connected by a sealing frame (9) to form a sealed box body, the interior of which is filled with liquid crystal as a liquid crystal layer (7); the ground plate (6) is provided with a coupling gap at the tail of the feeding network (3) and the inverted spiral microstrip line (801).

2. The liquid crystal based circularly polarized dielectric resonator two-dimensional beam scanning phased array antenna according to claim 1, characterized in that: The dielectric resonator (101) is in the shape of an elliptical cylinder and is used to realize circular polarization radiation; the 2N×2N dielectric resonator (101) is divided into a plurality of 2×2 subarrays; for each subarray, the upper left corner point is recorded as the origin, d is the period of the dielectric resonator 101, the dielectric resonator (101) located at the upper left position forms an angle of 45° with the edge of the flexible printed circuit board (2), and the dielectric resonators (101) at the upper right position, the lower right position and the lower left position in the 2×2 subarray are respectively obtained by rotating the dielectric resonator (101) at the upper left position clockwise by 90°, 180° and 270° with (d, d) as the center; the 2×2 subarray is extended with the subarray period 2d to form a dielectric resonator radiation unit layer (1).

3. The liquid crystal based circularly polarized dielectric resonator two-dimensional beam scanning phased array antenna according to claim 1, characterized in that: The feeding network (3) is an N+1-stage one-to-two T-junction microstrip power divider structure. N+1 The invention discloses a microstrip power divider; the output microstrip lines of each stage of the one-to-two T-junction microstrip power divider are of the same length, the characteristic impedance of the microstrip lines at the input and output ends is 100Ω, and a 1 / 4 waveguide wavelength impedance converter is used at the T-junction branch for impedance transformation; the input microstrip line of the first stage of the one-to-two T-junction microstrip power divider is cascaded with an impedance matching microstrip line as the input end of the feeding network (3); and the ground plate (6) is provided with a first coupling slot perpendicular to the output microstrip line of the N+1th stage of the one-to-two T-junction microstrip power divider in the feeding network (3).

4. The liquid crystal based circularly polarized dielectric resonator two-dimensional beam scanning phased array antenna according to claim 2, characterized in that The inverted spiral microstrip line phase shifter layer (8) comprises a bias network and 2N×2N inverted spiral microstrip lines (801); the 2N×2N inverted spiral microstrip lines (801) are divided into a plurality of 2×2 inverted spiral microstrip line groups; for each inverted spiral microstrip line group, the upper left corner point is recorded as the origin, and the inverted spiral microstrip lines (801) at the upper right, lower right and lower left positions are respectively obtained by rotating the inverted spiral microstrip line (801) at the upper left position by 90°, 180° and 270° clockwise around (d, d) as the center; for the inverted spiral microstrip line (801) at the upper left position, a 4λ length g ~6λ g The microstrip line is rotated clockwise, λ g The inverted spiral microstrip line (801) is connected to an L-shaped microstrip line at its starting end, and two L-shaped microstrip lines adjacent in the horizontal direction are in a vertical axis symmetrical structure, and two L-shaped microstrip lines adjacent in the vertical direction are in a horizontal axis symmetrical structure; the ground plate (6) is provided with a second coupling gap perpendicular to the inverted spiral microstrip line (801) at the end position of the inverted spiral microstrip line (801); the bias network is a 2N×2N AC bias line (802) connected to the corresponding inverted spiral microstrip line (801); the AC bias line (802) is provided with a length of λ g An open transmission line with a length of / 4 is used as a radio frequency isolation structure. One end of the open transmission line is connected to an AC bias line (802) at a distance λ from a connection point of the inverted spiral microstrip line (801). g / 4, and the other end is open; the control circuit is connected to the 2N×2N inverted spiral microstrip line (801) through a 2N×2N AC bias line (802) and is used to control the bias voltage of the inverted spiral microstrip line (801), and the control circuit is implemented by FPGA.

5. The liquid crystal based circularly polarized dielectric resonator two-dimensional beam scanning phased array antenna according to claim 1, characterized in that: N＝2。 6. The liquid crystal based circularly polarized dielectric resonator two-dimensional beam scanning phased array antenna according to claim 1, characterized in that: The dielectric constant of the glass substrates used in both the first glass substrate (5) and the second glass substrate (9) is 5.

8.

7. The liquid crystal based circularly polarized dielectric resonator two-dimensional beam scanning phased array antenna according to claim 1, characterized in that: The relative dielectric constant of the liquid crystal used in the liquid crystal layer (7) is adjusted in the range of 2.5 to 3.

52.

8. The liquid crystal based circularly polarized dielectric resonator two-dimensional beam scanning phased array antenna according to claim 1, characterized in that: The liquid crystal layer (7) is subjected to an alignment treatment, and when no bias voltage is applied, the liquid crystal molecules point in the same direction, and the liquid crystal material has a minimum dielectric constant; when a bias voltage is applied to the inverted spiral microstrip line (801) through a bias line, the liquid crystal molecules are deflected, the dielectric constant of the liquid crystal material changes, and the phase shift amount of the equivalent phase shifter corresponding to the inverted spiral microstrip line (801) changes, thereby achieving adjustment of the phase shift amount.

9. The liquid crystal based circularly polarized dielectric resonator two-dimensional beam scanning phased array antenna according to claim 4, characterized in that: Initial polarization phases of 0°, 90°, 180° and 270° are configured for the 2×2 subarray; the scanning phase required for each inverted spiral microstrip line (801) is calculated according to the beam pointing principle of the planar phased array and the required antenna beam azimuth angle, the scanning phase and the initial polarization phase are superimposed, and the bias voltage value corresponding to the liquid crystal is calculated, and the bias voltage is applied to the equivalent phase shifter of each inverted spiral microstrip line (801) through a bias network.

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