Two-dimensional scanning liquid crystal phased array

Abstract

A two-dimensional scanning liquid crystal phased array comprises an upper quartz glass substrate, a lower quartz glass substrate, a liquid crystal medium, a polyimide film, a coplanar waveguide transmission line, a liquid crystal phase shift feed network, a slot coupling patch antenna unit and a metal ground, and the liquid crystal phase shift feed network comprises a bias network, a one-to-multiple power divider, a direct current block and a liquid crystal phase shift unit. A plurality of coupling gaps, a plurality of direct current block gaps and a plurality of bias network gaps are formed in the metal ground, and the liquid crystal phase shifting units are correspondingly coupled with the gap coupling patch antenna units through the coupling gaps. According to the liquid crystal phased array, phase consistency is ensured, and the overall gain is remarkably improved. Meanwhile, the independent modulation of the phase of each antenna unit is realized, and through the design of a direct current block gap and a bias network gap on the metal ground, the insertion loss of a direct current bias line and a direct current block is effectively reduced, the total loss of the liquid crystal phased array is reduced, the regulation and control requirements of two-dimensional scanning are met, and the system performance is improved.

Description

Technical Field

[0001] The utility model relates to the field of wireless communication, and particularly to a two-dimensional scanning liquid crystal phased array. Background Art

[0002] To meet the various services of mobile terminals operating in L, C, Ku, Ka or W bands, such as wireless Internet, multimedia, communication and broadcast services, electronically reconfigurable millimeter-wave systems have become a current research hotspot due to their advantages of small volume, multi-function, high spectral efficiency, strong flexibility, etc., and are used in industrial ground station applications, including mobile terminals such as airborne, shipborne or automotive. The technical methods commonly used for phased array beam scanning include radio frequency microelectromechanical systems (RF MEMS), semiconductor solutions and ferroelectrics such as strontium barium titanate (BST). Another method is to use liquid crystal materials with low loss in the high-frequency band. Among these methods, liquid crystal is superior to MEMS in terms of lifespan, continuity and packaging; and is superior to BST in terms of frequency range and bias voltage, and is an ideal material for developing beam scanning phased arrays. Benefiting from the mature manufacturing process of liquid crystal display panels, liquid crystal phased arrays also have unique advantages in manufacturing cost. Therefore, researching liquid crystal phased arrays suitable for various mobile terminals is of great significance for wireless communication systems.

[0003] Liquid crystal phased arrays are small in volume, light in weight and low in power consumption, meeting the requirements of modern communication devices for being thin, light and low in power consumption. However, the gain of ordinary liquid crystal phased arrays is generally very low. Because during pattern scanning, large-angle scanning usually requires very long liquid crystal microstrip lines to provide a large phase difference between antenna radiation units, which will bring high losses to the phased array. In addition, the introduction of multiple liquid crystal DC bias lines, slot coupling and DC blocking modules will also bring high losses. Ordinary liquid crystal phased arrays usually also have the disadvantages of high cost and slow response.

[0004] It should be noted that the information disclosed in the above background art section is only used for understanding the background of the present application, and thus may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0005] The main purpose of the utility model is to overcome the defects of the above background art and provide a two-dimensional scanning liquid crystal phased array.

[0006] To achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A two-dimensional scanning liquid crystal phased array includes an upper quartz glass substrate, a lower quartz glass substrate, a liquid crystal medium disposed between the upper quartz glass substrate and the lower quartz glass substrate, polyimide films disposed above and below the liquid crystal medium, a coplanar waveguide transmission line and a liquid crystal phase-shifting feeding network disposed on the upper surface of the lower quartz glass substrate, a plurality of slot-coupled patch antenna units disposed on the upper surface of the upper quartz glass substrate, and a metal ground disposed on the lower surface of the upper quartz glass substrate; wherein, the coplanar waveguide transmission line is connected to the liquid crystal phase-shifting feeding network, the liquid crystal phase-shifting feeding network includes a bias network, a one-to-many power divider, a plurality of DC blocks and a plurality of liquid crystal phase-shifting units, the bias network is loaded on the one-to-many power divider, the output ports of the one-to-many power divider are respectively connected to the corresponding liquid crystal phase-shifting units through the respective DC blocks, a plurality of coupling slots, a plurality of DC block slots and a plurality of bias network slots are formed on the metal ground, each liquid crystal phase-shifting unit of the liquid crystal phase-shifting feeding network is correspondingly coupled to each slot-coupled patch antenna unit through the coupling slots, and each slot-coupled patch antenna unit is independently regulated through the corresponding liquid crystal phase-shifting unit, the plurality of DC block slots are correspondingly arranged with the respective DC blocks, and the plurality of bias network slots are correspondingly arranged with the DC bias lines in the bias network.

[0008] Further, the one-to-many power divider is a one-to-sixteen power divider, the liquid crystal phase-shifting feeding network includes 16 liquid crystal phase-shifting units, and is configured as a symmetric feeding network with four symmetric arms, wherein every 4 liquid crystal phase-shifting units are arranged in a group on the four arms respectively; correspondingly, 16 slot-coupled patch antenna units and 16 coupling slots are configured.

[0009] Further, the liquid crystal phase-shifting unit is configured as a bent and circuitous wiring structure.

[0010] Further, the slot-coupled patch antenna unit is a long rectangle, and the 16 slot-coupled patch antenna units form a 4×4 antenna array.

[0011] Further, the slot-coupled patch antenna units are arranged in a uniform planar array at intervals of 0.25λ to 1λ.

[0012] Further, the bias network includes upper and lower region DC bias lines and a middle region DC bias line, the upper and lower region DC bias lines penetrate into the inner side of the liquid crystal phase-shifting feeding network from the upper side and the lower side, and are connected to the liquid crystal phase-shifting units located inside the liquid crystal phase-shifting feeding network, and the bias network slots are only correspondingly arranged with the upper and lower region DC bias lines in the bias network.

[0013] Furthermore, the coplanar waveguide transmission line has a coplanar ground, which is not in the same plane as the metal ground of the slow-wave liquid crystal phase-shifting feeding network and is arranged in an interleaved and overlapping manner.

[0014] Furthermore, the coplanar metal ground of the coplanar waveguide transmission line is rounded.

[0015] In some specific embodiments, a two-dimensional scanning liquid crystal phased array includes a coplanar waveguide transmission line, a liquid crystal phase-shifting feeding network, a metal defect ground, a slot-coupled patch antenna unit, and upper and lower quartz glass substrates, and further includes polyimide films disposed above and below the liquid crystal medium as alignment layers for liquid crystal medium molecules.

[0016] In some specific embodiments, the liquid crystal phase-shifting feeding network includes: a liquid crystal medium, a polyimide film, a bias network, a DC pad, a DC block, a one-to-sixteen power divider, and a liquid crystal phase-shifting unit. The liquid crystal medium is aligned by the polyimide film and fixed between the upper and lower quartz glass substrates.

[0017] In some specific embodiments, the metal defect ground includes: a coupling slot of the patch antenna unit, a DC block slot, a bias network slot, and a cross-aligned slot.

[0018] In some specific embodiments, the coplanar waveguide transmission line is connected to the front end of a one-to-sixteen power divider. Sixteen liquid crystal phase-shifting units are respectively located on the lower glass substrate of sixteen slot-coupled patch antenna units and are on the same layer as the DC block and the bias network. Sixteen slot-coupled patch antenna units are evenly distributed on the upper surface of the upper glass substrate.

[0019] Optionally, the sixteen slot-coupled patch antenna units are fed in opposite directions in pairs; preferably, the sixteen slot-coupled patch antenna units are all fed in the same direction.

[0020] Optionally, the DC block is loaded at the output port of a one-to-four power divider; preferably, the DC block is loaded at the output port of a one-to-sixteen power divider.

[0021] Optionally, the bias network is loaded on the same side of the one-to-sixteen power divider; preferably, the bias network is symmetrically arranged and is respectively located on both sides of the one-to-sixteen power divider.

[0022] Optionally, the slot-coupled patch antenna units are arranged in a uniform planar array at intervals of 0.25λ to 1λ; preferably, the end-fire antenna units are evenly arranged as a planar array at an interval of 0.8λ.

[0023] Optionally, the coplanar waveguide transmission line and the metal ground of the upper quartz glass substrate are symmetrically arranged; preferably, the coplanar waveguide transmission line and the metal ground are overlapped.

[0024] Optionally, the coplanar metal ground of the coplanar waveguide transmission line is not chamfered; preferably, the coplanar metal ground of the coplanar waveguide transmission line is rounded.

[0025] Optionally, the thickness of the liquid crystal medium is 5 - 200 microns; preferably, the thickness of the liquid crystal medium is 100 microns.

[0026] Optionally, the liquid crystal phase shifter unit uses a slow-wave transmission line; preferably, the liquid crystal phase shifter unit uses a common microstrip transmission line.

[0027] Optionally, the upper glass substrate is completely aligned with the lower glass substrate; preferably, the upper glass substrate and the lower glass substrate are arranged in an interleaved manner.

[0028] The utility model has the following beneficial effects:

[0029] The two-dimensional scanning liquid crystal phased array of the utility model realizes a one-to-multiple power distribution network with good phase consistency through innovative design. It not only meets the control requirements of two-dimensional scanning through the design of the patch antenna unit fed by slot coupling, but also ensures that the initial phases of each slot-coupled patch antenna unit are consistent, thereby improving the overall gain performance. The utility model uses a feeding network with multiple DC blocks to realize the independent modulation ability of the phase of each slot-coupled patch antenna unit. At the same time, the utility model also introduces the design of DC block slots and bias network slots on the metal ground, effectively reducing the insertion loss of the DC bias line and the DC block, thereby effectively reducing the total loss of the liquid crystal phased array. The utility model realizes a high gain of 15.4 dBi at a center frequency of 30 GHz. Further, the liquid crystal phase shifter unit is configured into a bent and circuitous shape design, which can ensure the initial phases of each liquid crystal phase shifter unit are consistent while maximizing the use of the wiring space around the liquid crystal phase shifter unit to make the phase-shifting microstrip line long enough to increase the adjustable phase range. Further, the utility model solves the problem of ground discontinuity between the liquid crystal phase shifter feeding network and the feeding microstrip line through coplanar waveguide transmission line feeding, which helps to improve the system integration and miniaturization.

[0030] The combination of the slot-coupled patch antenna array and the liquid crystal feeding network in the utility model, combined with the design of the metal defect ground to reduce the insertion loss of the DC bias line and the DC block, realizes a low-profile high-gain, two-dimensional scanning phased array, which is beneficial to the miniaturization and integrated processing of the liquid crystal phased array. In the preferred solution, the bias network slots of the metal defect ground are optimized, and only the bias lines penetrating into the liquid crystal phase shifter feeding network are processed to prevent RF signal leakage and avoid adverse effects on RF signal transmission caused by excessive metal defect ground defects.

[0031] In summary, the liquid crystal phased array of the present utility model not only has high gain and flexible two-dimensional scanning ability, but also reduces system loss through optimized design, improves the integration level and miniaturization level, provides strong technical support for the integration and development of reconfigurable millimeter-wave systems, and shows the potential for wide application in the field of wireless communication.

[0032] Other beneficial effects in the embodiments of the present utility model will be further described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a three-dimensional view of a two-dimensional scanning liquid crystal phased array according to an embodiment of the present utility model;

[0034] Figure 2 is a top view of the lower quartz glass substrate of a two-dimensional scanning liquid crystal phased array according to an embodiment of the present utility model;

[0035] Figure 3 is a bottom view (left) and a top view (right) of the upper quartz glass substrate of a two-dimensional scanning liquid crystal phased array according to an embodiment of the present utility model;

[0036] Figure 4 are the S parameters of a two-dimensional scanning liquid crystal phased array according to an embodiment of the present utility model;

[0037] Figure 5 is the gain diagram of a two-dimensional scanning liquid crystal phased array according to an embodiment of the present utility model;

[0038] Figure 6 is the pattern scanning diagram of a two-dimensional scanning liquid crystal phased array according to an embodiment of the present utility model at Phi = 90 plane;

[0039] Figure 7 is the pattern scanning diagram of a two-dimensional scanning liquid crystal phased array according to an embodiment of the present utility model at Phi = 0 plane;

[0040] Figure 8 are the S parameters of a one-to-sixteen power divider of a two-dimensional scanning liquid crystal phased array according to an embodiment of the present utility model;

[0041] Figure 9 is the phase diagram of a one-to-sixteen power divider of a two-dimensional scanning liquid crystal phased array according to an embodiment of the present utility model.

[0042] Figure 10 is a schematic diagram of beam scanning of the liquid crystal phased array according to an embodiment of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] The following provides a detailed description of the embodiments of the present utility model. It should be emphasized that the following description is merely exemplary and not intended to limit the scope and application of the present utility model.

[0044] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, the connection can be for fixing or for coupling or communicating purposes.

[0045] It should be understood that the orientation or positional relationship indicated by terms such as "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present invention and for simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0046] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present invention, "a plurality of" means two or more, unless otherwise specifically defined.

[0047] Refer to Figures 1 to 3, an embodiment of the present utility model provides a two-dimensional scanning liquid crystal phased array, which includes an upper quartz glass substrate 102, a lower quartz glass substrate 109, a liquid crystal medium 105 disposed between the upper quartz glass substrate 102 and the lower quartz glass substrate 109, and polyimide films 104, 106 disposed above and below the liquid crystal medium, a coplanar waveguide transmission line 110 and a liquid crystal phase shift feeding network arranged on the upper surface of the lower quartz glass substrate 109, a plurality of slot-coupled patch antenna units 101 arranged on the upper surface of the upper quartz glass substrate 102, and a metal ground 103 arranged on the lower surface of the upper quartz glass substrate 102; wherein, the coplanar waveguide transmission line 110 is connected to the liquid crystal phase shift feeding network, and the liquid crystal phase shift feeding network includes a bias network 112, a one-to-many power divider (such as a one-to-sixteen power divider 111), a plurality of DC blocks 113 and a plurality of liquid crystal phase shift units 107. The bias network 112 is loaded on the one-to-many power divider. The output ports of the one-to-many power divider are respectively connected to the corresponding liquid crystal phase shift units 107 through the respective DC blocks 113. A plurality of coupling slots 117, a plurality of DC block slots 118 and a plurality of bias network slots 119 are formed on the metal ground 103. Each liquid crystal phase shift unit 107 of the liquid crystal phase shift feeding network is correspondingly coupled to each slot-coupled patch antenna unit 101 through the coupling slot 117. Each slot-coupled patch antenna unit 101 is independently regulated through the corresponding liquid crystal phase shift unit 107. The plurality of DC block slots 118 are correspondingly arranged with the respective DC blocks 113, and the plurality of bias network slots 119 are correspondingly arranged with the DC bias lines in the bias network 112.

[0048] Referring to Figure 2 , in a preferred embodiment, the one-to-many power divider is a one-to-sixteen power divider 111, and the liquid crystal phase shift feeding network includes 16 liquid crystal phase shift units 107, configured as a symmetric feeding network with four symmetric arms, wherein every 4 liquid crystal phase shift units are grouped and arranged on the four arms respectively; correspondingly, 16 slot-coupled patch antenna units and 16 coupling slots are configured.

[0049] Referring to Figure 2 , in a preferred embodiment, each liquid crystal phase shift unit 107 is configured as a bent and circuitous wiring structure. The liquid crystal phase shift unit in this embodiment is configured as a bent and circuitous shape design, as Figure 2 shown, which can ensure the same initial phase of each liquid crystal phase shift unit while maximizing the use of the wiring space around the liquid crystal phase shift unit to make the phase shift microstrip line long enough, and improving the adjustable phase range.

[0050] Referring to Figure 1 and Figure 3, in a preferred embodiment, the slot-coupled patch antenna unit 101 is a long rectangle, and the 16 slot-coupled patch antenna units 101 form a 4×4 antenna array. In a preferred embodiment, the slot-coupled patch antenna units are arranged in a uniform planar array at intervals of 0.25λ to 1λ.

[0051] Refer to Figure 2 , in a preferred embodiment, the bias network 112 includes upper and lower region DC bias lines and a middle region DC bias line. The upper and lower region DC bias lines penetrate into the inner side of the liquid crystal phase-shifting feeding network from the upper side and the lower side, and are connected to the liquid crystal phase-shifting units located inside the liquid crystal phase-shifting feeding network. The bias network slot 119 is only correspondingly arranged corresponding to the upper and lower region DC bias lines in the bias network 112, as Figure 3 shown. Through this optimized design of the bias network slot on the metal ground, only the bias lines penetrating into the liquid crystal phase-shifting feeding network are processed to prevent RF signal leakage, and at the same time, the adverse impact on RF signal transmission caused by excessive metal defect ground defects is avoided.

[0052] The high-gain, two-dimensional scanning liquid crystal phased array according to the embodiment of the present invention realizes a one-to-multiple power distribution network with good phase consistency through innovative design. It not only meets the regulation requirements of two-dimensional scanning through the design of the slot-coupled fed patch antenna unit, but also ensures the initial phase consistency of each slot-coupled patch antenna unit, thereby improving the overall gain performance. The present invention uses a feeding network with multiple DC blocks to realize the independent modulation ability of the phase of each slot-coupled patch antenna unit. At the same time, the design of DC block slots and bias network slots on the metal ground is introduced, effectively reducing the insertion loss of the DC bias line and the DC block, and thus effectively reducing the total loss of the liquid crystal phased array. The present invention realizes a high gain of 15.4 dBi at a center frequency of 30 GHz. The combination of the slot-coupled patch antenna array and the liquid crystal feeding network in the present invention, combined with the design of reducing the insertion loss of the DC bias line and the DC block by the metal defect ground, realizes a low-profile high-gain, two-dimensional scanning phased array, which is beneficial to the miniaturization and integrated processing of the liquid crystal phased array. Generally speaking, the liquid crystal phased array of the present invention not only has high gain and flexible two-dimensional scanning ability, but also reduces the system loss through optimized design, improves the integration level and miniaturization level, and can provide strong technical support for the integration and development of reconfigurable millimeter-wave systems.

[0053] The following further describes the specific embodiments of the present invention.

[0054] As Figures 1 - 3As shown in the figure, a two-dimensional scanning liquid crystal phased array according to an embodiment of the present invention includes a coplanar waveguide transmission line 110, a liquid crystal phase shift feeding network, a metal ground 103, a slot-coupled patch antenna unit 101, and upper and lower quartz glass substrates 102 and 109. It further includes polyimide films 104 and 106 disposed above and below the liquid crystal medium 105 as alignment layers for liquid crystal medium molecules.

[0055] The liquid crystal phase shift feeding network includes: a liquid crystal medium 105, polyimide films 104 and 106, a bias network 112, a DC pad 108, a DC block 113, a one-to-sixteen power divider 111, and liquid crystal phase shift units 107. The liquid crystal medium 105 is aligned by the polyimide films 104 and 106 and fixed between the upper and lower quartz glass substrates 102 and 109.

[0056] Coupling slots 117 for the patch antenna unit, DC block slots 118, bias network slots 119, and cross-aligned slots 115 are formed on the metal ground 103.

[0057] The coplanar waveguide transmission line 110 is connected to the front end of the one-to-sixteen power divider 111. Sixteen liquid crystal phase shift units 107 are respectively located on the lower glass substrate 109 of sixteen slot-coupled patch antenna units 101 and are on the same layer as the DC block 113 and the bias network 112. Sixteen slot-coupled patch antenna units 101 are evenly distributed on the upper surface of the upper glass substrate 102.

[0058] The bent and circuitous shape design can ensure the same initial phase of each liquid crystal phase shift unit while maximizing the use of the wiring space below the unit, making the phase shift microstrip line long enough to increase the adjustable phase range.

[0059] The coplanar waveguide transmission line 110, the one-to-sixteen power divider 111, the liquid crystal phase shift units 107, the bias network 112, and the DC pad 108 are all located on the upper surface of the lower quartz glass substrate 109. The metal ground 103 is located on the lower surface of the upper quartz glass substrate 102.

[0060] The liquid crystal is aligned by the polyimide films 104 and 106 as alignment layers, sealed between the upper quartz glass substrate 102 and the lower quartz glass substrate 109, and evenly distributed above the liquid crystal phase shift units 107.

[0061] In the embodiment as Figure 3 shown, the geometric shape of the DC block slot 118 of the metal ground 103 is an H-shaped slot. It can also be a slot of any other shape. The slot shape can be selected according to the actual situation to minimize the insertion loss of the DC block.

[0062] The bias network gap 119 of the metal ground 103 is arranged corresponding to the position of the DC bias line, preventing the leakage of radio frequency signals through the DC bias line, thereby reducing the insertion loss of the DC bias network.

[0063] The phase consistency of the one-to-sixteen power divider in the embodiment of the present utility model is good, enabling each slot-coupled patch antenna unit to obtain equal initial phases, thereby realizing a high-gain liquid crystal phased array.

[0064] Due to space limitations, the liquid crystal phase shifter unit may have insufficient phase shift due to too short a phase-shifting microstrip line. The embodiment can load a slow-wave structure on the phase-shifting microstrip line to alleviate the problem of small phase shift. The slow-wave structure can adopt (but is not limited to) the slow-wave transmission line structure disclosed in the patent with the publication number CN116960585B of the applicant.

[0065] In the two-dimensional scanning liquid crystal phased array of the embodiment of the present utility model, the bias network can be loaded on the same side of the one-to-sixteen power divider or on both sides of the one-to-sixteen power divider. It is preferably to adopt a symmetrically arranged bias network, effectively optimizing the loss of the system.

[0066] Further details are as Figures 1 - 3 shown. A two-dimensional scanning liquid crystal phased array includes a coplanar waveguide transmission line 110, a liquid crystal phase-shifting feeding network, a metal ground 103, a slot-coupled patch antenna unit 101, and upper and lower quartz glass substrates 102, 109. It also includes polyimide films 104, 106 arranged above and below the liquid crystal medium 105 as the alignment layers of the liquid crystal medium molecules.

[0067] As Figure 1 shown, the liquid crystal phased array consists of a sandwich stack structure composed of a lower quartz glass substrate, an upper quartz glass substrate, a liquid crystal medium, and a metal layer. The overall size of the liquid crystal phased array is 50×50×1.056 mm 3 . Among them, the upper quartz glass substrate is 40×35×0.5 mm 3 ; the lower quartz glass substrate is 50×50×0.5 mm 3 ; the metal ground size is 40×35×0.5 mm 3 ; the thickness of the liquid crystal medium is 0.05 mm, and the thickness of all metal lines is 0.003 mm. The overall size of the coplanar ground of the coplanar waveguide transmission line is 14×10 mm 2 , the width of the coplanar waveguide transmission line is 0.4 mm; the gap between the coplanar waveguide transmission line and the coplanar ground is 0.1 mm. And, at the position where the coplanar ground of the coplanar waveguide transmission line intersects with the metal ground of the slow-wave liquid crystal phase-shifting feeding network, a fillet with a radius of 5 mm is formed, facilitating the smoother transition of alternating current between metal grounds not in the same plane.

[0068] AsFigure 2 As shown, the liquid crystal phase shifter feeding network, the bias network, the DC block, the coplanar waveguide transmission line, and the one-to-sixteen power divider are all located on the upper surface of the lower quartz glass substrate. The bias network is symmetrically distributed on both sides of the one-to-sixteen power divider; the DC block is arranged before each liquid crystal phase shifter unit. As Figure 3 shown, the metal defect ground is located on the lower surface of the upper quartz glass substrate, and the sixteen slot-coupled patch antenna units are evenly distributed on the upper surface of the upper quartz glass substrate.

[0069] As Figure 4 shown, it is the S-parameters of a two-dimensional scanning liquid crystal phased array.

[0070] As Figure 5 shown, it is the gain pattern of a two-dimensional scanning liquid crystal phased array, and a gain of 15.4 dBi can be obtained at the center frequency of 30 GHz.

[0071] As Figure 6 shown, it is the pattern scanning diagram of the Phi = 90 plane of a two-dimensional scanning liquid crystal phased array, which can achieve a scan of ±24°, and the gain is in the range of 13 - 15.4 dBi during the scanning process.

[0072] As Figure 7 shown, it is the pattern scanning diagram of the Phi = 0 plane of a two-dimensional scanning liquid crystal phased array, which can achieve a scan of ±22°, and the gain is in the range of 13 - 15.4 dBi during the scanning process.

[0073] As Figures 8 to 9 shown, it is the S-parameters and phase curve of the one-to-sixteen power divider in a two-dimensional scanning liquid crystal phased array. It can be seen that the designed one-to-sixteen power divider has good phase stability, the phase of each port is basically consistent, and the phase deviation between ports is less than 3 degrees.

[0074] The high-gain, two-dimensional scanning liquid crystal phased array of the present utility model realizes a one-to-many power distribution network with good phase consistency through innovative design. Not only does the patch antenna unit design with slot coupling feeding meet the regulation requirements of two-dimensional scanning, improve the phase modulation range under limited physical size, and enhance the flexibility of the liquid crystal phased array, but also ensures the initial phase consistency of each slot-coupled patch antenna unit, thereby improving the overall gain performance. At the same time, the innovative design of the metal defect ground also reduces the loss of the feeding network, especially effectively reducing the insertion loss of the DC bias line and DC block of the bias network. The present utility model realizes a high-gain liquid crystal phased array, which can achieve high-gain, two-dimensional, continuous beam scanning within a 30 GHz frequency range, with a scanning angle up to ±22° in the Phi = 0 plane and ±24° in the Phi = 90 plane, and the gain within the scanning range is 12.1 dBi to 15.3 dBi. The two-dimensional scanning liquid crystal phased array provided by the present utility model is expected to be widely applied in the field of wireless communication.

[0075] The above content is a further detailed description of the present utility model in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present utility model is only limited to these descriptions. For those of ordinary skill in the technical field to which the present utility model belongs, without departing from the concept of the present utility model, several alternatives or modifications can be made to these described embodiments, and these alternative or modified forms should be regarded as belonging to the protection scope of the present utility model. In the description of this specification, the description with reference to terms such as "an embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. Without conflict, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present utility model and their advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the scope of protection of the patent application.

Claims

1. A two-dimensional scanning liquid crystal phased array, characterized in that: The invention comprises an upper quartz glass substrate, a lower quartz glass substrate, a liquid crystal medium arranged between the upper quartz glass substrate and the lower quartz glass substrate, a polyimide film arranged above and below the liquid crystal medium, a coplanar waveguide transmission line and a liquid crystal phase shift feeding network arranged on the upper surface of the lower quartz glass substrate, a plurality of slot-coupled patch antenna units arranged on the upper surface of the upper quartz glass substrate, and a metal ground arranged on the lower surface of the upper quartz glass substrate; wherein the coplanar waveguide transmission line is connected to the liquid crystal phase shift feeding network, and the liquid crystal phase shift feeding network comprises a bias network, a one-to-many power distributor, a plurality of DC blocks and A plurality of liquid crystal phase shift units, the bias network is loaded on the one-to-many power distributor, the output ports of the one-to-many power distributor are respectively connected to the corresponding liquid crystal phase shift units through each DC block, a plurality of coupling slots, a plurality of DC block slots and a plurality of bias network slots are opened on the metal ground, each liquid crystal phase shift unit of the liquid crystal phase shift feed network is coupled with each slot-coupled patch antenna unit through the coupling slot, each slot-coupled patch antenna unit is independently regulated by the corresponding liquid crystal phase shift unit, the plurality of DC block slots are arranged corresponding to each DC block, and the plurality of bias network slots are arranged corresponding to the DC bias line in the bias network.

2. The two-dimensional scanning liquid crystal phased array according to claim 1, characterized in that: The one-to-many power divider is a one-to-sixteen power divider, and the liquid crystal phase shift feeding network includes 16 liquid crystal phase shift units, which are configured into a symmetrical feeding network with four symmetrical arms, wherein each group of four liquid crystal phase shift units are arranged on four arms respectively; accordingly, 16 slot-coupled patch antenna units and 16 coupling slots are configured.

3. The two-dimensional scanning liquid crystal phased array according to claim 1, characterized in that: The liquid crystal phase shift unit is configured as a meandering wiring structure.

4. The two-dimensional scanning liquid crystal phased array according to claim 2, characterized in that: The slot-coupled patch antenna unit is a long rectangular strip, and the 16 slot-coupled patch antenna units form a 4×4 antenna array.

5. The two-dimensional scanning liquid crystal phased array according to claim 4, characterized in that: The slot-coupled patch antenna units are arranged into a uniform array at intervals of 0.25λ to 1λ.

6. The two-dimensional scanning liquid crystal phased array according to any one of claims 1 to 5, characterized in that: The bias network includes upper and lower area DC bias lines and a middle area DC bias line. The upper and lower area DC bias lines extend from the upper and lower sides into the inner side of the liquid crystal phase shift feed network and are connected to the liquid crystal phase shift unit located on the inner side of the liquid crystal phase shift feed network. The bias network gap is only arranged corresponding to the upper and lower area DC bias lines in the bias network.

7. The two-dimensional scanning liquid crystal phased array according to any one of claims 1 to 5, characterized in that: The coplanar waveguide transmission line has a coplanar ground, which is not in the same plane as the metal ground of the slow-wave liquid crystal phase-shift feeding network and is arranged in a staggered and overlapping manner.

8. The two-dimensional scanning liquid crystal phased array according to claim 7, characterized in that: The coplanar metal ground of the coplanar waveguide transmission line is rounded.

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