Liquid crystal phase shifter, liquid crystal phased array antenna and terminal equipment
By using a liquid crystal phase shifter in the terminal equipment, the dielectric constant and electromagnetic wave propagation speed are controlled by the deflection angle of the liquid crystal molecules, the problem of high cost of electronic phased array antennas is solved, and cost reduction and phase shifting performance are improved.
Patent Information
- Application Number
- CN202411877223.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-18
- Publication Date
- 2025-03-21
AI Technical Summary
The existing electronic phased array antennas are costly, mainly due to the use of a large number of phase shifter chips and TR component chips.
A liquid crystal phase shifter is adopted, including a stacked slow-wave transmission line, a liquid crystal structure layer and a metal defect-based metal, and the deflection angle of the liquid crystal molecules is controlled through the copper bias line, thereby changing the dielectric constant and electromagnetic wave propagation speed to achieve phase control.
By replacing the traditional phase shifter chip, the liquid crystal phase shifter can reduce the cost of the terminal equipment while maintaining good phase shifting performance, which is about 1/10 of the traditional solution.
Smart Images
Figure CN119674537A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of electronic technology, and in particular to a liquid crystal phase shifter, a liquid crystal phased array antenna and a terminal device. Background Art
[0002] Currently, the ground terminals of low-orbit satellites use traditional electronic phased array antenna solutions, which are light and easy to carry, and have LTE (Long Term Evolution)-level network speeds. However, the electronic phased array antenna solution uses a large number of chips, such as phase shifter chips and TR (Transmitter and Receiver) component chips, which are relatively expensive.
[0003] Therefore, the current technology needs to be further improved. Summary of the invention
[0004] The object of the present invention is to provide a liquid crystal phase shifter, a liquid crystal phased array antenna and a terminal device, which can alleviate the problem of high cost of current electronic phased array antennas.
[0005] In order to achieve the above object, the present invention adopts the following technical solutions:
[0006] The embodiment of the present application provides a liquid crystal phase shifter, comprising a slow-wave transmission line, a liquid crystal structure layer and a metal defect ground arranged in a stacked manner, wherein the liquid crystal structure layer comprises a liquid crystal layer, a first liquid crystal alignment layer and a second liquid crystal alignment layer, and the liquid crystal layer is located between the first liquid crystal alignment layer and the second liquid crystal alignment layer;
[0007] A copper bias line is arranged between the slow-wave transmission line and the liquid crystal structure layer, and the copper bias line is connected to the slow-wave transmission line; the copper bias line is used to control the deflection angle of liquid crystal molecules in the liquid crystal layer according to an input voltage.
[0008] In the liquid crystal phase shifter of some embodiments, the slow-wave transmission line includes a microstrip line and a slow-wave structure located on the microstrip line; a defect corresponding to the slow-wave structure of the slow-wave transmission line is arranged on the metal defect ground;
[0009] The microstrip line includes a first branch line and a second branch line, one end of the first branch line is connected to one end of the second branch line, and the other end of the first branch line and the other end of the second branch line are both free ends; the first branch line extends along a first direction, the second branch line extends along a second direction, and the first direction and the second direction intersect;
[0010] The slow-wave structure includes a plurality of first rectangular branches arranged along a first direction and a plurality of second rectangular branches arranged along a second direction.
[0011] In some embodiments of the liquid crystal phase shifter, a plurality of first rectangular branches are arranged alternately at intervals on both sides of the first branch line; a plurality of second rectangular branches are arranged alternately at intervals on both sides of the second branch line;
[0012] The first intervals between two adjacent first rectangular branches on the same side are the same; the second intervals between two adjacent second rectangular branches on the same side are the same.
[0013] In some embodiments of the liquid crystal phase shifter, the first direction and the second direction are perpendicular.
[0014] In some embodiments of the liquid crystal phase shifter, the first interval is the same as the second interval.
[0015] In some embodiments of the liquid crystal phase shifter, the metal defect includes first coupling slits arranged at intervals along the first direction and second coupling slits arranged at intervals along the second direction, and the third intervals between adjacent first coupling slits are the same, and the fourth intervals between adjacent second coupling slits are the same.
[0016] In the liquid crystal phase shifter of some embodiments, the first coupling slit and the second coupling slit have the same size.
[0017] In some embodiments of the liquid crystal phase shifter, the operating frequency band of the liquid crystal phase shifter is 18.7 GHz to 20.2 GHz.
[0018] An embodiment of the present application further provides a liquid crystal phased array antenna, which includes the above-mentioned liquid crystal phase shifter.
[0019] An embodiment of the present application further provides a terminal device, which includes the above-mentioned liquid crystal phase shifter.
[0020] Compared with the prior art, the present application provides a liquid crystal phase shifter, a liquid crystal phased array antenna and a terminal device, wherein the liquid crystal phase shifter combined with the array antenna can form a liquid crystal phased array antenna in the terminal device; relative to the electronic phased array antenna, the phase shifting function is achieved by setting a liquid crystal phase shifter instead of the original phase shifter chip; at the same time, a large number of TR component chips can be saved, thereby reducing the cost of the terminal device. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is a schematic diagram of the structure of the liquid crystal phase shifter provided in this application.
[0022] Figure 2 This is a schematic diagram of the structure of the slow-wave transmission line in the liquid crystal phase shifter provided in this application.
[0023] Figure 3 It is a schematic diagram of the partial structure of the slow-wave transmission line of the liquid crystal phase shifter provided in this application.
[0024] Figure 4 In the liquid crystal phase shifter provided in this application Figure 2 Dimensional diagram.
[0025] Figure 5 In the liquid crystal phase shifter provided in this application Figure 3 Dimensional diagram.
[0026] Figure 6 It is a schematic diagram of the structure of the metal defect ground in the liquid crystal phase shifter provided in this application.
[0027] Figure 7 It is a schematic diagram of the local structure of the metal defect in the liquid crystal phase shifter provided in this application.
[0028] Figure 8 In the liquid crystal phase shifter provided in this application Figure 6 Dimensional diagram.
[0029] Fig. 9 In the liquid crystal phase shifter provided in this application Figure 7 Dimensional diagram.
[0030] Fig.10 This is a resonance diagram of the liquid crystal molecules in the liquid crystal phase shifter provided in the present application being in a vertical direction.
[0031] Fig.11 This is a resonance diagram of the liquid crystal molecules in the liquid crystal phase shifter provided in the present application being at an angle of 45 degrees.
[0032] Fig.12 This is a resonance diagram of the liquid crystal molecules in the liquid crystal phase shifter provided in the present application in the horizontal direction.
[0033] Fig.13 This is a schematic diagram of the loss value of the liquid crystal molecules in the vertical direction in the liquid crystal phase shifter provided in this application.
[0034] Fig.14 This is a schematic diagram of the loss value of the liquid crystal molecules in the liquid crystal phase shifter provided in this application when they are at an angle of 45 degrees.
[0035] Fig.15 This is a schematic diagram of the loss value of liquid crystal molecules in the horizontal direction in the liquid crystal phase shifter provided in this application.
[0036] Fig.16 This is a schematic diagram of the phase shift amount of the liquid crystal phase shifter provided in this application at a frequency of 18.7 GHz.
[0037] Fig.17 This is a schematic diagram of the phase shift amount of the liquid crystal phase shifter provided in this application at a frequency of 19.5 GHz.
[0038] Fig.18 This is a schematic diagram of the phase shift amount of the liquid crystal phase shifter provided in this application at a frequency of 20.2 GHz. DETAILED DESCRIPTION
[0039] In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.
[0040] See also Figure 1 , the present application provides a liquid crystal phase shifter, which includes a slow-wave transmission line 11, a liquid crystal structure layer 12 and a metal defect ground 13 arranged in a stacked manner, the liquid crystal structure layer 12 includes a liquid crystal layer, a first liquid crystal orientation layer and a second liquid crystal orientation layer, the liquid crystal layer is located between the first liquid crystal orientation layer and the second liquid crystal orientation layer; the first liquid crystal orientation layer and the second liquid crystal orientation layer are both used to arrange the liquid crystal molecules in the liquid crystal layer in an orderly manner. A copper bias line is arranged between the slow-wave transmission line 11 and the liquid crystal structure layer 12, and the copper bias line is connected to the slow-wave transmission line 11; the copper bias line is used to control the deflection angle of the liquid crystal molecules in the liquid crystal layer according to the input voltage, thereby changing the dielectric constant of the liquid crystal material, and then changing the propagation speed of the electromagnetic wave in the phase shifter, generating different time delay differences, to achieve the purpose of changing the phase.
[0041] The liquid crystal phase shifter in this embodiment is combined with an array antenna to form a liquid crystal phased array antenna in a terminal device. Compared with an electronic phased array antenna, a phase shifting function is achieved by providing a liquid crystal phase shifter to replace the original phase shifter chip. At the same time, a large number of TR component chips can be saved, thereby reducing the cost of the terminal device.
[0042] In some embodiments, the liquid crystal phase shifter further includes a first glass substrate 14, a second glass substrate 15, a first protective layer and a second protective layer. The first glass substrate 14 is located near the metal defect ground 13 and is stacked on the metal defect ground 13, the second glass substrate 15 is located near the slow-wave transmission line 11, the first protective layer is located between the metal defect ground 13 and the liquid crystal layer, and the second protective layer is located between the slow-wave transmission line 11 and the copper bias line. The first protective layer and the second protective layer are both silicon dioxide anti-oxidation layers; the first protective layer is sprayed on the metal defect ground 13 to prevent the metal defect ground 13 from being oxidized; the second protective layer is sprayed on the slow-wave transmission line 11, that is, the phase shifter layer, to prevent the slow-wave transmission line 11 from being oxidized, thereby improving the reliability of the liquid crystal phase shifter.
[0043] As an embodiment, the liquid crystal phase shifter includes a second glass substrate 15, a slow wave transmission line 11, a second protective layer, a copper bias line, a second liquid crystal orientation layer, a liquid crystal layer, a first liquid crystal orientation layer, a first protective layer, a metal defect ground 13 and a first glass substrate 14. The thickness of each structural layer in the liquid crystal phase shift layer is shown in Table 1:
[0044] First glass substrate 300um Metal Defects 2.2um First protective layer 100nm~200nm First liquid crystal alignment layer 50nm~100nm Liquid crystal layer 15.6um Second liquid crystal alignment layer 50nm~100nm Copper bias line 2.2um Second protective layer 100nm~200nm Slow wave transmission line 2.2um Second glass substrate 300um
[0045] Table 1
[0046] The thickness of the liquid crystal layer in this embodiment is about 15 um, which can match the production process of liquid crystal panels and is suitable for large-scale mass production of liquid crystal panels.
[0047] See also Figure 2 and Figure 3 In some embodiments, the slow-wave transmission line 11 includes a microstrip line and a slow-wave structure located on the microstrip line; the metal defect ground 13 is provided with defects corresponding to the slow-wave structure of the slow-wave transmission line 11, that is, the metal defect ground 13 is provided with gaps adapted to the slow-wave structure. The microstrip line includes a first branch line 111 and a second branch line 112, one end of the first branch line 111 is connected to one end connected to the second branch line 112, and the other end of the first branch line 111 and the other end of the second branch line 112 are both free ends; the first branch line 111 extends along a first direction (such as the X direction in the figure), and the second branch line 112 extends along a second direction (such as the Y direction in the figure), and the first direction and the second direction intersect; the slow-wave structure includes a plurality of first rectangular branches 113 arranged along the first direction and a plurality of second rectangular branches 114 arranged along the second direction, such as Figure 4 As shown, the length of the plurality of first rectangular branches 113 arranged along the first direction, such as W7, is smaller than the length of the plurality of second rectangular branches 114 arranged along the second direction, such as L7.
[0048] As an embodiment, a plurality of first rectangular branches 113 are arranged alternately at intervals on both sides of the first branch line 111; a plurality of second rectangular branches 114 are arranged alternately at intervals on both sides of the second branch line 112; a first interval (such as Figure 5 The second interval (eg, Figure 5 L9) in the same, and the first interval is the same as the second interval, that is, the size of the first rectangular branch 113 and the second rectangular branch 114 in this embodiment is the same, such as Figure 5 W8 in is the same as L8.
[0049] As an embodiment, the first direction and the second direction are perpendicular, that is, the microstrip line in this embodiment is arranged in a bent shape, so that the first rectangular branch 113 and the second rectangular branch 114 are arranged at intervals along two directions.
[0050] See also Figure 6 and Figure 7 As an embodiment, the metal defect ground 13 includes first coupling slots 131 arranged at intervals along a first direction and second coupling slots 132 arranged at intervals along a second direction, wherein the lengths of the plurality of first coupling slots 131 arranged along the first direction (e.g. Figure 8 W1 in the figure is greater than the length of the plurality of second coupling slots 132 arranged along the second direction (eg Figure 8 L1 in the figure); a third interval between adjacent first coupling gaps 131 (such as Fig. 9 The fourth interval (eg, Fig. 9 The first coupling slot 131 and the second coupling slot 132 have the same size. Fig. 9 L2 in is the same as W2.
[0051] Please also read Figure 4 , Figure 5 , Figure 8 and Fig. 9 As an embodiment, the structural dimensions of the slow-wave transmission line 11 and the structural dimensions of the metal defect ground 13 are shown in Table 2:
[0052] parameter Dimensions / mm parameter Dimensions / mm parameter Dimensions / mm parameter Dimensions / mm <![CDATA[L0]]> 14.00 <![CDATA[L1]]> 6.24 <![CDATA[L2]]> 1.34 <![CDATA[L3]]> 1.00 <![CDATA[L4]]> 0.04 <![CDATA[L5]]> 0.06 <![CDATA[L6]]> 7.24 <![CDATA[L7]]> 6.24 <![CDATA[L8]]> 0.04 <![CDATA[L9]]> 0.16 <![CDATA[L 10 ]]> 0.04 <![CDATA[L 11 ]]> 0.35 <![CDATA[W0]]> 9.10 <![CDATA[W1]]> 4.14 <![CDATA[W2]]> 1.34 <![CDATA[W3]]> 0.97 <![CDATA[W4]]> 0.04 <![CDATA[W5]]> 0.06 <![CDATA[W6]]> 6.45 <![CDATA[W7]]> 4.14 <![CDATA[W8]]> 0.04 <![CDATA[W9]]> 0.16 <![CDATA[W 10 ]]> 0.04 <![CDATA[W 11 ]]> 1.66
[0053] Table 2
[0054] Please also read Fig.10 , Fig.11 and Fig.12 As an embodiment, when the liquid crystal molecules are in the vertical direction, the dielectric constant and loss tangent are 2.46 and 0.0116 respectively; when the liquid crystal molecules are in the 45-degree angle direction, the dielectric constant and loss tangent are 3.00 and 0.009 respectively; when the liquid crystal molecules are in the horizontal direction, the dielectric constant and loss tangent are 3.53 and 0.0064 respectively. Fig.10 is the resonance diagram of the liquid crystal molecules in the liquid crystal phase shifter in the vertical direction, Fig.11 This is the resonance diagram of the liquid crystal molecules in the liquid crystal phase shifter at an angle of 45 degrees. Fig.12 This is the resonance diagram of the liquid crystal molecules in the liquid crystal phase shifter in the horizontal direction. Fig.10 , Fig.11 and Fig.12It can be seen that the resonance depths of the three directions of the liquid crystal molecules within the effective bandwidth (18.7 GHz to 20.2 GHz) are all better than -14 dB, indicating that the impedance matching is good.
[0055] Please also read Fig.13 , Fig.14 and Fig.15 , as an example, Fig.13 It is a schematic diagram of the loss value when the liquid crystal molecules in the liquid crystal phase shifter are in the vertical direction; Fig.14 This is a schematic diagram of the loss value when the liquid crystal molecules in the liquid crystal phase shifter are at a 45-degree angle. Fig.15 This is a schematic diagram of the loss value of the liquid crystal molecules in the liquid crystal phase shifter in the horizontal direction. Fig.13 , Fig.14 and Fig.15 It can be seen that the loss values of the phase shifters corresponding to the three directions of the liquid crystal molecules are similar, and the average loss within the effective bandwidth (18.7GHz~20.2GHz) is 10.5dB. This part of the loss includes the line loss (2.1dB) other than the phase shifter. Therefore, the loss of the actual liquid crystal phase shifter needs to be subtracted from this line loss, that is, 10.5-2.1=8.4dB. The liquid crystal phase shifter in this embodiment can achieve lower loss.
[0056] See also Fig.16 , as an example, Fig.16 Schematic diagram of the phase shift of the liquid crystal phase shifter at a frequency of 18.7 GHz. Specifically, taking 18.7 GHz as an example, starting from the vertical direction of the liquid crystal molecules, the corresponding phase is -105.2°, after the liquid crystal molecules are at an angle of 45°, the corresponding phase is 38.7°, and finally the liquid crystal molecules are in the horizontal direction, the corresponding phase is -156.8°. It can be calculated that the phase of the liquid crystal molecules in the horizontal direction surpasses the state of the liquid crystal molecules in the vertical direction. Therefore, the calculation formula of the phase shift of the liquid crystal phase shifter at 18.7 GHz in this embodiment is:
[0057] The phase shift at 18.7 GHz = 156.8° - 105.2° + 360° = 411.6°.
[0058] It can be seen from this that the phase shift of the liquid crystal phase shifter at 18.7 GHz is 411.6°, which exceeds 360°, and the phase shift performance is good.
[0059] See also Fig.17 , as an example, Fig.17Schematic diagram of the phase shift of the liquid crystal phase shifter at a frequency of 19.5 GHz. Specifically, taking 19.5 GHz as an example, starting from the vertical direction of the liquid crystal molecules, the corresponding phase is 119.0°, after the liquid crystal molecules are at a 45° angle, the corresponding phase is -111.6°, and finally the liquid crystal molecules are in the horizontal direction, the corresponding phase is 39.8°. It can be calculated that the phase of the liquid crystal molecules in the horizontal direction surpasses the state of the liquid crystal molecules in the vertical direction. Therefore, the calculation formula of the phase shift of the liquid crystal phase shifter at 19.5 GHz in this embodiment is:
[0060] The phase shift at 19.5 GHz = 119.0° - 39.8° + 360° = 439.2°.
[0061] It can be seen from this that the phase shift of the liquid crystal phase shifter at 19.5 GHz is 439.2°, which exceeds 360°, and the phase shift performance is good.
[0062] See also Fig.18 , as an example, Fig.18 Schematic diagram of the phase shift of the liquid crystal phase shifter at a frequency of 20.2 GHz. Specifically, taking 20.2 GHz as an example, starting from the vertical direction of the liquid crystal molecules, the corresponding phase is -5.0°, after the liquid crystal molecules are at an angle of 45°, the corresponding phase is 115.6°, and finally the liquid crystal molecules are in the horizontal direction, the corresponding phase is -106.2°. It can be calculated that the phase of the liquid crystal molecules in the horizontal direction surpasses the state of the liquid crystal molecules in the vertical direction. Therefore, the calculation formula of the phase shift of the liquid crystal phase shifter at 20.2 GHz in this embodiment is:
[0063] The phase shift at 20.2 GHz = 106.2° - 5.0° + 360° = 461.2°.
[0064] It can be seen from this that the phase shift of the liquid crystal phase shifter at 20.2 GHz is 461.2°, which exceeds 360°, and the phase shift performance is good.
[0065] As an embodiment, the size of the liquid crystal phase shifter is 14.0mm*9.1mm*0.7mm. Specifically, the length and width of the first glass substrate 14 are 14.0mm*9.1mm; the length and width of the metal defect ground 13 are 14.0mm*9.1mm, the length and width of the liquid crystal layer are 14.0mm*9.1mm; the length and width of the area occupied by the slow-wave transmission line 11 are 14.0mm*9.1mm; the length and width of the second glass substrate 15 are 14.0mm*9.1mm.
[0066] The liquid crystal phase shifter in this embodiment has a loss of 8.4dB within the effective bandwidth of low-orbit satellite communication, such as 18.7GHz to 20.2GHz, and can achieve a phase shift of more than 410°, and the phase shifter has good performance. The liquid crystal phase shifter is combined with the antenna array to form a liquid crystal phased array antenna, which is applied to ground terminal equipment of low-orbit satellites. The cost is about 1 / 10 of the electronic phased array solution of low-orbit satellite ground terminals, which greatly reduces the cost of low-orbit satellite ground terminals. In addition, the thickness of the liquid crystal layer in the liquid crystal phase shifter is relatively thin, which is suitable for existing screen panel production lines and can be mass-produced. It should be noted that the liquid crystal phase shifter in this embodiment can also be applied to ground terminals of high-orbit satellites, millimeter-wave phased array antenna terminals in the agricultural and medical fields, etc., and this application is not limited to this.
[0067] A liquid crystal phased array antenna is also disclosed in an embodiment of the present application. The liquid crystal phased array antenna includes the above-mentioned liquid crystal phase shifter. Since the liquid crystal phase shifter is described in detail above, it will not be repeated here.
[0068] A terminal device is also disclosed in an embodiment of the present application. The terminal device includes the above-mentioned liquid crystal phase shifter. Since the liquid crystal phase shifter is described in detail above, it will not be repeated here.
[0069] The liquid crystal phase shifter provided in the embodiments of the present application is introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solution and its core idea of the present application. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A liquid crystal phase shifter, characterized in that: It comprises a slow-wave transmission line, a liquid crystal structure layer and a metal defect ground arranged in a stacked manner, wherein the liquid crystal structure layer comprises a liquid crystal layer, a first liquid crystal alignment layer and a second liquid crystal alignment layer, and the liquid crystal layer is located between the first liquid crystal alignment layer and the second liquid crystal alignment layer; A copper bias line is provided between the slow-wave transmission line and the liquid crystal structure layer, and the copper bias line is connected to the slow-wave transmission line; the copper bias line is used to control the deflection angle of the liquid crystal molecules in the liquid crystal layer according to the input voltage.
2. The liquid crystal phase shifter according to claim 1, characterized in that: The slow-wave transmission line includes a microstrip line and a slow-wave structure located on the microstrip line; the metal defect ground is provided with defects corresponding to the slow-wave structure of the slow-wave transmission line; The microstrip line includes a first branch line and a second branch line, one end of the first branch line is connected to one end of the second branch line, and the other end of the first branch line and the other end of the second branch line are both free ends; the first branch line extends along a first direction, the second branch line extends along a second direction, and the first direction and the second direction intersect; The slow-wave structure includes a plurality of first rectangular branches arranged along a first direction and a plurality of second rectangular branches arranged along the second direction.
3. The liquid crystal phase shifter according to claim 2, characterized in that: A plurality of the first rectangular branches are arranged alternately at intervals on both sides of the first branch line; a plurality of the second rectangular branches are arranged alternately at intervals on both sides of the second branch line; The first intervals between two adjacent first rectangular branches on the same side are the same; the second intervals between two adjacent second rectangular branches on the same side are the same.
4. The liquid crystal phase shifter according to claim 2, characterized in that: The first direction and the second direction are perpendicular.
5. The liquid crystal phase shifter according to claim 3, characterized in that: The first interval is the same as the second interval.
6. The liquid crystal phase shifter according to claim 2, characterized in that: The metal defect ground includes first coupling slots arranged at intervals along the first direction and second coupling slots arranged at intervals along the second direction, and third intervals between adjacent first coupling slots are the same, and fourth intervals between adjacent second coupling slots are the same.
7. The liquid crystal phase shifter according to claim 6, characterized in that: The first coupling slot and the second coupling slot have the same size.
8. The liquid crystal phase shifter according to claim 7, characterized in that: The operating frequency band of the liquid crystal phase shifter is 18.7 GHz to 20.2 GHz.
9. A liquid crystal phased array antenna, characterized in that: The liquid crystal phased array antenna comprises the liquid crystal phase shifter as described in any one of claims 1-8.
10. A terminal device, characterized in that: The terminal device comprises the liquid crystal phase shifter as claimed in any one of claims 1 to 8.