Glass-based multi-beam liquid crystal phased array antenna device

Abstract

The application discloses a kind of glass-based multi-beam liquid crystal phased array antenna devices, belong to phased array antenna field.It includes the composite substrate that multiple layer PCB and glass panel are pasted, and it is bound to the film driving plate on one side of composite substrate, and there is liquid crystal display circuit special driving chip on film driving plate, and the other side of composite substrate is bound to flexible circuit board;Composite substrate at least includes antenna plate layer, upper glass layer, lower glass layer, and feed plate layer composition;Upper glass layer, lower glass layer are encapsulated with microwave liquid crystal between, form liquid crystal box;The multi-beam liquid crystal phased array antenna device has two independent receiving beam forming networks and an independent transmitting beam forming network, and has two receiving beams and a transmitting beam.In the application scenario of satellite communication, the two receiving beams of the multi-beam liquid crystal phased array antenna device can be aligned and tracked to different target satellites respectively.

Description

Technical Field

[0001] The present invention relates to the technical field of phased array antennas, and in particular to a multi-beam liquid crystal phased array antenna device based on a glass substrate. Background Art

[0002] Phased array antennas are antennas that change their radiation pattern by controlling the feed phase of the radiating elements in the array. By controlling the phase, the direction of the antenna's maximum radiation pattern is changed, achieving beam scanning. Due to their beam scanning properties, phased array antennas are widely used in fields such as communications and detection.

[0003] Phased array antenna architectures are categorized as active and passive. Current glass-based liquid crystal phased array antennas are essentially typical passive phased arrays, demonstrating high maturity, low cost, and low power consumption. Liquid crystal phased array antennas utilize the dielectric anisotropy of liquid crystals to provide deflection voltages to the upper and lower layers of the liquid crystal layer via transmission lines. This control of the liquid crystal deflection direction alters the phase shifter's phase shift, thereby adjusting the phased array antenna's beam direction. Related technologies have proposed a series of liquid crystal-based phase shifter structures and the resulting phased array solutions. By filling liquid crystal material between dielectric substrates such as glass or PCBs and applying different DC voltages to control the material properties of the liquid crystal material to create different transmission phase values, passive phased array technology based on liquid crystal technology is implemented, enabling widespread application in communications, detection, and other fields.

[0004] The common points of the above solutions are mainly that they all include a radiating element group, an RF power division network, and an electrically adjustable delay phase shifter group. Since they are passive phased array systems, the main problems now are: first, the passive phased array architecture, due to the cascade structure formed by the multi-stage power division network and the lack of a power compensation mechanism (that is, there is no active chip for compensation), will result in a transmission link insertion loss of more than 5-6dB; second, the use of traditional analog beamforming, so a single synthesis channel only generates a single beam, which cannot meet the needs of multiple beams. Summary of the Invention

[0005] The present invention provides a glass-based multi-beam liquid crystal phased array antenna device. Through a co-aperture arrangement, a low-noise amplifier (LNA) chip is added in front of the liquid crystal phase shifter. A single antenna channel adopts a dual phase shifter architecture to form two sets of beamforming power splitter networks. At the same time, an independent transmit beamforming network is provided, thereby realizing dual receive beams for receiving signals and one transmit beam for transmitting signals.

[0006] An embodiment of the present invention provides a glass-based multi-beam liquid crystal phased array antenna device, comprising the following steps: forming a composite substrate formed by laminating a multi-layer PCB and a glass panel; bonding a chip-on-film driver board to one side of the composite substrate, wherein a dedicated driver chip for a liquid crystal display circuit is provided on the chip-on-film driver board; and bonding a flexible printed circuit board to the other side of the composite substrate;

[0007] The composite substrate is provided with N×M (M≥1 and N≥1) periodically arranged liquid crystal phased array receiving units, an active LNA chip corresponding to the liquid crystal phased array receiving units, and J×K (J≥1 and K≥1) periodically arranged liquid crystal phased array transmitting units;

[0008] The composite substrate comprises at least an antenna plate layer, an upper glass layer, a lower glass layer and a feed plate layer; and microwave liquid crystal is encapsulated between the upper glass layer and the lower glass layer to form a liquid crystal cell;

[0009] The flexible circuit board is used to provide power signals and control signals to the active LNA chip;

[0010] The chip-on-film driving board is used to provide driving and control signals to the liquid crystal phase shifter in the liquid crystal cell;

[0011] The multi-beam liquid crystal phased array antenna device is provided with two independent receiving channels and one independent transmitting channel, and has two mutually independent receiving beamforming networks and one independent transmitting beamforming network, and has two receiving beams and one transmitting beam.

[0012] Optionally, in one embodiment of the present invention, the liquid crystal phase shifter transmission line in the liquid crystal box is a coplanar waveguide line structure consisting of strip lines with branches.

[0013] Optionally, in one embodiment of the present invention, the material of the liquid crystal phase shifter transmission line in the liquid crystal box is one or more of indium tin oxide, silver, graphene, copper, nickel, and molybdenum.

[0014] Optionally, in one embodiment of the present invention, a metallized glass through hole is provided in the glass layer of the composite substrate.

[0015] Optionally, in one embodiment of the present invention, a beamforming network consisting of multi-stage power splitters is provided on the feed board layer of the composite substrate, and the beamforming network is in the form of one or more of stripline, microstrip line or coplanar waveguide line.

[0016] Optionally, in one embodiment of the present invention, in an application scenario of satellite communication, two receiving beams are respectively aimed at and track different target satellites.

[0017] Optionally, in one embodiment of the present invention, in an application scenario of satellite communication, two receiving beams are respectively aimed at and track the main target satellite and the backup satellite, and the transmitting beam is aimed at and track the main target satellite to form a main communication link and an alternative communication link.

[0018] Optionally, in one embodiment of the present invention, two receiving beams are respectively aimed at and track two target satellites, and the transmitting beam is switched between the two target satellites to form two communication links in a time-division situation.

[0019] The glass-based multi-beam liquid crystal phased array antenna device according to the embodiment of the present invention has the following beneficial effects:

[0020] 1. The present invention has a single transmit beam and dual receive beams. When applied in satellite communication scenarios, it can search for and track another satellite while maintaining the current satellite communication link to achieve agile switching of the satellite network.

[0021] 2. An active LNA chip is added to the receiving chain to compensate for the insertion loss of the multi-stage reactive power distribution network, and has a better G / T value than the traditional purely passive liquid crystal phased array antenna.

[0022] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0024] Figure 1 Schematic diagram of a glass-based multi-beam liquid crystal phased array antenna device according to an embodiment of the present invention;

[0025] Figure 2 This is a principle block diagram of a glass-based multi-beam liquid crystal phased array antenna device according to an embodiment of the present invention;

[0026] Figure 3 An example of a layered structure of a composite substrate according to an embodiment of the present invention;

[0027] FIG4 is a specific implementation example of each layer of the layered structure of the composite substrate according to an embodiment of the present invention, wherein Figures 4a to 4f Corresponding respectively Figure 3 Layers 81 to 84;

[0028] Figure 5 The figure illustrates an application scenario of a glass-based multi-beam liquid crystal phased array antenna device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0030] The glass-based multi-beam liquid crystal phased array antenna device includes: a composite substrate formed by laminating a multi-layer PCB and a glass panel, a chip-on-film (COF) driver board bonded to one side of the composite substrate, and a dedicated driver chip for the liquid crystal display circuit on the COF driver board, and a flexible circuit (FPC) board bonded to the other side of the composite substrate;

[0031] The composite substrate is provided with N×M (M≥1 and N≥1) periodically arranged liquid crystal phased array receiving units, an active LNA chip corresponding to the liquid crystal phased array receiving units, and J×K (J≥1 and K≥1) periodically arranged liquid crystal phased array transmitting units;

[0032] The composite substrate comprises at least an antenna plate layer, an upper glass layer, a lower glass layer and a feed plate layer; and microwave liquid crystal is encapsulated between the upper glass layer and the lower glass layer to form a liquid crystal cell;

[0033] The flexible circuit board is used to provide power and control signals to the active LNA chip;

[0034] The chip-on-film driver board is used to provide drive and control signals to the liquid crystal phase shifter in the liquid crystal cell;

[0035] The multi-beam liquid crystal phased array antenna device is provided with two independent receiving channels and one independent transmitting channel, and has two mutually independent receiving beamforming networks and one independent transmitting beamforming network, and has two receiving beams and one transmitting beam.

[0036] like Figure 1 and Figure 2As shown, a glass-based multi-beam liquid crystal phased array antenna device includes: N×M liquid crystal phased array receiving units 1 arranged periodically (M≥1 and N≥1), each equipped with an active LNA chip 2 corresponding to the liquid crystal phased array receiving units 1; and J×K liquid crystal phased array transmitting units 11 arranged periodically (J≥1 and K≥1). The liquid crystal phased array receiving units 1, liquid crystal phased array transmitting units 11, and active LNA chip 2 are all disposed on a composite substrate 8 formed by laminating a multi-layer PCB and a glass panel. A chip-on-film (COF) driver board 6 is bonded to one side of the composite substrate 8, and a dedicated liquid crystal display circuit driver chip 61 is provided on the COF driver board 6. A flexible circuit (FPC) board 7 is bonded to the other side of the composite substrate 8. The COF driver board 6 provides control cables for driving the liquid crystal phase shifters 3, 3', and 13 in the liquid crystal phased array, and the FPC board 7 provides cables for driving and controlling the active LNA chip 2.

[0037] In the aforementioned multi-beam liquid crystal phased array antenna device, its receiving antenna channel, i.e., the subsequent stage of the active LNA chip 2 corresponding to each liquid crystal phased array receiving unit 1, is provided with two liquid crystal phase shifters 3 and 3'. The arrays of these liquid crystal phase shifters 3 and 3' correspond to two multi-stage power splitter networks 4 and 4', respectively, thus forming two independent receiving channels Rx1 and Rx2, i.e., having dual receiving beams.

[0038] Similarly, in the above-mentioned multi-beam liquid crystal phased array antenna device, its transmitting antenna channel, that is, the subsequent stage of each liquid crystal phased array transmitting unit 11 is provided with a liquid crystal phase shifter 13. The array of liquid crystal phase shifters 13 corresponds to the multi-stage power division network 14, thus forming a transmitting channel Tx, that is, having a transmitting beam.

[0039] Optionally, in one embodiment of the present invention, the liquid crystal phase shifter transmission line in the liquid crystal cell is a coplanar waveguide line structure consisting of strip lines with branches.

[0040] The following combination Figure 3 4 further illustrates the detailed structure of the composite substrate 8.

[0041] The composite substrate 8 is made of a multi-layer PCB and a glass panel, and the layers are bonded together using optical glue or prepreg. From top to bottom, it includes: an antenna layer 81, an upper glass layer 82, a lower glass layer 83, and a feed layer 84. The upper glass layer 82, the lower glass layer 83, and the frame glue 85 form a liquid crystal box, which is encapsulated with microwave liquid crystal 86. The antenna layer 81 and the feed layer 84 are typically made of a multi-layer PCB. Figure 1 The COF driving plate 6 shown is bound to the inner side of the glass plate layer 82 of the composite substrate 8. Figure 1The FPC board 7 shown is pressed in the middle of the multi-layer PCB of the antenna board layer 81 of the composite substrate 8.

[0042] Optionally, in one embodiment of the present invention, the material of the liquid crystal phase shifter transmission line in the liquid crystal cell is one or more of indium tin oxide, silver, graphene, copper, nickel, and molybdenum.

[0043] Optionally, in one embodiment of the present invention, a metallized through-glass hole is provided in the glass layer of the composite substrate.

[0044] Optionally, in one embodiment of the present invention, a beamforming network consisting of multi-stage power splitters is provided on the feed board layer of the composite substrate, and the beamforming network is in the form of one or more of stripline, microstrip line or coplanar waveguide line.

[0045] On the upper surface of the antenna board layer 81 of the composite substrate 8, there are N×M radiating patches 811 of liquid crystal phased array receiving units 1 arranged in a periodic arrangement (M≥1 and N≥1), and there are also active LNA chips 2 corresponding to the liquid crystal phased array receiving units 1, and J×K radiating patches 812 of liquid crystal phased array transmitting units 11 arranged in a periodic arrangement (J≥1 and K≥1). Because the antenna board layer 81 is made of a multi-layer PCB, the radiating patch 811 is connected to the input of the active LNA chip 2 (not shown) via metallized vias and RF transmission lines in the form of strip lines, microstrip lines, or coplanar waveguide lines within the board layer. Furthermore, the power and control lines of the active LNA chip 2 are connected to the FPC board 7 (not shown) via internal wiring. Furthermore, the output of the active LNA chip 2 is connected to the RF terminal 813 on the bottom surface of the antenna board layer 81 via metallized vias and RF transmission lines in the form of strip lines, microstrip lines, or coplanar waveguide lines within the board layer.

[0046] Similarly, the radiation patch 812 on the upper surface of the antenna board layer 81 is connected to the RF endpoint 814 on the lower surface of the antenna board layer 81 through metallized vias inside the board layer, and RF transmission lines in the form of strip lines, microstrip lines, or coplanar waveguide lines.

[0047] Generally, the radiation patches 811 and 812 are in a rectangular, square, or circular shape.

[0048] Metallized glass through-holes (TGVs) 821 and 822 are provided in the upper glass layer 82, which correspond to the RF endpoints 813 and 814 on the lower surface of the antenna board layer 81, respectively, and ensure RF conduction after bonding, and are used to connect the RF signal of the antenna board layer 81 with the upper glass layer 82 (i.e., the phase shifter of the liquid crystal box).

[0049] The lower surface of the upper glass layer 82 is provided with periodically arranged strip lines 823 and 823' with branches. The number of the strip lines 823 and 823' with branches corresponds to the number of the radiating patches 811, and the strip lines 823 and 823' are connected to the metallized glass through-hole 821 via a one-to-two power splitting structure. Similarly, the lower surface of the upper glass layer 82 is also provided with periodically arranged strip lines 824 with branches. The number of the strip lines 824 with branches corresponds to the number of the radiating patches 812, and one end of the strip line 824 is connected to the metallized glass through-hole 822.

[0050] The upper surface of the lower glass layer 83 is provided with periodically arranged strip metal ground planes 831 and 832. The strip metal ground planes 831 correspond to the branches of the strip lines 823 and 823' with branches of the upper glass layer 82, while the strip metal ground planes 832 correspond to the branches of the strip line 824 with branches of the upper glass layer 82. In other words, the strip metal ground planes 831 and the strip lines 823 and 823' with branches of the upper glass layer 82 form a set of parallel coplanar waveguide (CPW) lines, while the strip metal ground planes 832 and the strip line 824 with branches of the upper glass layer 82 form another set of coplanar waveguide (CPW) lines. The use of coplanar waveguide (CPW) lines has the advantage of miniaturizing the liquid crystal phase shift structure and achieving a high figure of merit (FoM).

[0051] The strip lines 823 and 823' with branches and the strip metal ground 831, as well as the microwave liquid crystal 86 encapsulated between the upper and lower glass layers 82 and 83 form a Figure 2 The liquid crystal phase shifter structure 3 and 3 '; similarly, the strip line 824 with branches and the strip metal ground 832, as well as the microwave liquid crystal 86 encapsulated between the upper and lower glass layers 82 and 83 form Figure 2 The liquid crystal phase shifter structure 13; at the same time, an ITO control line (not shown in the figure) connected to the strip lines 823 and 823', and the strip line 824 is provided on the upper glass layer 82, which is used to provide a driving / control voltage value to the liquid crystal phase shifter structures 3 and 3', and the liquid crystal phase shifter structure 13. The ITO control line will eventually be connected to the dedicated liquid crystal display circuit driver chip 61 on the COF driver board 6.

[0052] A metal ground plane 843 covers the entire top surface of the feed plate layer 84. This metal ground plane 843 is provided with a pair of slits 841 and 841' arranged in a periodic pattern of N x M, corresponding one-to-one with the ends of the striplines 823 and 823'. Similarly, a pair of slits 842 is arranged in a periodic pattern of J x K, corresponding one-to-one with the ends of the stripline 824. Slits 841, 841', and 842 connect the RF signal from the underlying glass layer 83 (i.e., the phase shifter within the liquid crystal cell) to the feed plate layer 84.

[0053] The feed board layer 84 is a multi-layer PCB board. The board layer has metalized vias and RF transmission lines in the form of strip lines, microstrip lines, or coplanar waveguide lines to form a multi-level power splitting network (not shown in the figure). Finally, two receiving ports Rx1 and Rx2 and a transmitting port Tx are formed on the lower surface of the feed board layer 84, which corresponds to the formation of two receiving beams and one transmitting beam. It should be noted that the multi-level power splitting network in the feed board layer 84 is independently provided with a multi-level power splitting network of two receiving channels and a multi-level power splitting network of one transmitting channel (i.e. Figure 2 The multi-level power division networks 4, 4' and 14) are respectively Figure 2 The liquid crystal phase shifter structures 3 and 3 ′ and the liquid crystal phase shifter structure 13 are connected to realize two receiving channels and one transmitting channel.

[0054] Optionally, in one embodiment of the present invention, in an application scenario of satellite communication, two receiving beams are respectively aimed at and track different target satellites.

[0055] Optionally, in one embodiment of the present invention, in an application scenario of satellite communication, two receiving beams are respectively aimed at and track the main target satellite and the backup satellite, and the transmitting beam is aimed at and track the main target satellite to form a main communication link and an alternative communication link.

[0056] Optionally, in one embodiment of the present invention, two receiving beams are respectively aimed at and track two target satellites, and the transmitting beam is switched between the two target satellites to form two communication links in a time-division situation.

[0057] The following combination Figure 5 To illustrate the application scenario of the multi-beam liquid crystal phased array antenna device described above, when the multi-beam liquid crystal phased array antenna device 53 operates in a satellite communication scenario, during the communication process, the receiving beam 531 and transmitting beam 532 of the multi-beam liquid crystal phased array antenna device 53 are respectively aimed at the target satellite 51, establishing a bidirectional communication link for transmission and reception and maintaining the connection, and the receiving beam 531 and transmitting beam 532 are respectively always tracking the target satellite 51; at the same time, the receiving beam 531' of the multi-beam liquid crystal phased array antenna device 53 is used to aim at another target satellite 52 and always keep tracking the target satellite 52, forming an alternative communication link. When satellite switching is required, the link can be quickly switched to communication with the target satellite 52. That is, the control software only needs to align the transmitting beam 532 with the target satellite 52 to establish a communication link, and then the original receiving beam 531 can set the next alternative target satellite for tracking.

[0058] Without loss of generality, during the communication process, the receiving beam 531 and the receiving beam 531' of the multi-beam liquid crystal phased array antenna device 53 are respectively aligned with and keep tracking the target satellites 51 and 52, while the transmitting beam 532 is switched between the target satellites 51 and 52 according to the time slot requirements of different transmission carriers, forming a two-way communication link with the target satellites 51 and 52 simultaneously under time division.

[0059] According to an embodiment of the present invention, a glass-based multi-beam liquid crystal phased array antenna device is proposed, which includes a composite substrate formed by laminating multiple layers of PCBs and glass panels. A chip-on-film (COF) driver board is bound to one side of the composite substrate, and a dedicated driver chip for the liquid crystal display circuit is provided on the COF driver board, while a flexible circuit (FPC) board is bound to the other side of the composite substrate; the composite substrate comprises at least an antenna board layer, an upper glass layer, a lower glass layer, and a feed board layer; and microwave liquid crystal is encapsulated between the upper glass layer and the lower glass layer to form a liquid crystal box. The device has two independent receiving beam forming networks and an independent transmitting beam forming network, and has two receiving beams and one transmitting beam. In the application scenario of satellite communication, the two receiving beams of the multi-beam liquid crystal phased array antenna device can be respectively aimed at and track different target satellites.

[0060] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions 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 N embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0061] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "N" means at least two, such as two, three, etc., unless otherwise specifically defined.

Claims

1. A multi-beam liquid crystal phased array antenna device based on a glass substrate, characterized in that: include: A composite substrate made of a multi-layer PCB and a glass panel, with a chip-on-film driver board attached to one side of the composite substrate, and a dedicated driver chip for the liquid crystal display circuit on the chip-on-film driver board, and a flexible circuit board attached to the other side of the composite substrate; The composite substrate is provided with N×M periodically arranged liquid crystal phased array receiving units, an active LNA chip corresponding to the liquid crystal phased array receiving units, and J×K periodically arranged liquid crystal phased array transmitting units, wherein M≥1 and N≥1, J≥1 and K≥1; The composite substrate comprises at least an antenna plate layer, an upper glass layer, a lower glass layer and a feed plate layer; and microwave liquid crystal is encapsulated between the upper glass layer and the lower glass layer to form a liquid crystal cell; The flexible circuit board is used to provide power signals and control signals to the active LNA chip; The chip-on-film driving board is used to provide driving and control signals to the liquid crystal phase shifter in the liquid crystal cell; The multi-beam liquid crystal phased array antenna device is provided with two independent receiving channels and one independent transmitting channel, and has two mutually independent receiving beamforming networks and one independent transmitting beamforming network, and has two receiving beams and one transmitting beam.

2. The device according to claim 1, characterized in that The liquid crystal phase shifter transmission line in the liquid crystal box is a coplanar waveguide line structure composed of strip lines with branches.

3. The device according to claim 1 or 2, characterized in that The liquid crystal phase shifter transmission line material in the liquid crystal cell is one or more of indium tin oxide, silver, graphene, copper, nickel, and molybdenum.

4. The device according to claim 1, characterized in that A metallized glass through hole is provided in the glass layer of the composite substrate.

5. The device according to claim 1, characterized in that A beamforming network consisting of multi-stage power dividers is provided on the feed board layer of the composite substrate. The beamforming network is in the form of one or more of a stripline, a microstrip line or a coplanar waveguide line.

6. The device according to claim 1, characterized in that In satellite communication application scenarios, two receiving beams are respectively aimed at and track different target satellites.

7. The device according to claim 1, characterized in that In the application scenario of satellite communication, two receiving beams are respectively aimed at and track the main target satellite and the backup satellite, and the transmitting beam is aimed at and track the main target satellite, forming a main communication link and an alternative communication link.

8. The device according to claim 1, characterized in that The two receiving beams are respectively aimed at and track the two target satellites, and the transmitting beam is switched between the two target satellites, forming two communication links in a time-division situation.

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