Liquid crystal phase shifter and liquid crystal antenna

Abstract

The invention relates to the technical field of wireless communication, in particular to a liquid crystal phase shifter and a liquid crystal antenna. The liquid crystal phase shifter comprises a liquid crystal box and a radio frequency substrate, the liquid crystal box comprises a first substrate and a second substrate which are oppositely arranged, a liquid crystal layer located between the first substrate and the second substrate, a first microstrip line and a first metal layer, the first microstrip line is located on the side, facing the second substrate, of the first substrate, the first metal layer is located on the side, facing the first substrate, of the second substrate, and the first metal layer is grounded; the radio frequency substrate comprises a third substrate and a second microstrip line located on one side of the third substrate. And the first microstrip line is electrically connected with the second microstrip line through the connecting structure. According to the invention, radiation loss and unexpected radiation can be reduced, and the accuracy and power of signal transmission can be improved.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of wireless communication, and in particular to a liquid crystal phase shifter and a liquid crystal antenna. BACKGROUND

[0002] The liquid crystal phase shifter is an electrically controlled phase control device based on the adjustable dielectric constant of liquid crystal material, and has important application value in modern phased array antennas, microwave tuning circuits and radar systems. The core working principle is that by changing the bias voltage applied to the liquid crystal cell, the orientation of the liquid crystal molecules in the cell is controlled, thereby continuously changing the equivalent dielectric constant and realizing the precise phase shift of the transmitted radio frequency signal.

[0003] The radio frequency signal of the liquid crystal phase shifter needs to be transmitted in a sealed liquid crystal cell. At present, the transmission line in the cell and the external upper and lower radio frequency circuits are usually interconnected by electromagnetic coupling. However, since the coupling area is essentially an open electromagnetic field window, it is difficult to achieve complete shielding, which will cause part of the radio frequency energy to leak out in the form of electromagnetic waves, resulting in serious unintended radiation, causing transmission signal deviation, low transmission signal power, and difficulty in improving the radiation power. SUMMARY

[0004] In order to solve the above technical problems or at least partially solve the above technical problems, the present disclosure provides a liquid crystal phase shifter and a liquid crystal antenna, which are beneficial to reduce radiation loss and unintended radiation, and improve the accuracy and power of the transmission signal.

[0005] The present disclosure provides a liquid crystal phase shifter, comprising: a liquid crystal cell and a radio frequency substrate; the liquid crystal cell comprises a first substrate and a second substrate arranged oppositely, a liquid crystal layer between the first substrate and the second substrate, and a first microstrip line and a first metal layer, the first microstrip line is located on the side of the first substrate facing the second substrate, and the first metal layer is located on the side of the second substrate facing the first substrate, and the first metal layer is grounded; the radio frequency substrate comprises a third substrate and a second microstrip line on one side of the third substrate; a connecting structure, the first microstrip line is electrically connected with the second microstrip line through the connecting structure.

[0006] The present disclosure also provides a liquid crystal antenna comprising the above liquid crystal phase shifter.

[0007] The technical solution provided by the present disclosure has the following advantages compared with the prior art: The liquid crystal phase shifter provided by the present disclosure comprises a liquid crystal box, wherein the liquid crystal box comprises a first substrate and a second substrate arranged oppositely, and a liquid crystal layer between the first substrate and the second substrate. The liquid crystal box further comprises a first microstrip line and a first metal layer, the first microstrip line is located on the side of the first substrate facing the second substrate, and the first metal layer is located on the side of the second substrate facing the first substrate, the first metal layer is grounded, the first microstrip line is used for transmitting a bias signal while transmitting a radio frequency signal, the bias voltage in the first microstrip line and the ground potential of the first metal layer form an electric field for controlling the deflection of liquid crystal molecules in the liquid crystal layer, so as to change the dielectric constant of the liquid crystal molecules, the radio frequency signal realizes phase shift in the liquid crystal layer, and the effect of changing the microwave phase is achieved. The liquid crystal phase shifter further comprises a radio frequency substrate and a connecting structure, the radio frequency substrate comprises a third substrate and a second microstrip line located on one side of the third substrate, the first microstrip line can be electrically connected with the second microstrip line through the connecting structure, so that the radio frequency signal on the first microstrip line can be directly transmitted to the second microstrip line, or the radio frequency signal on the second microstrip line can be directly transmitted to the first microstrip line, that is, the radio frequency signal can be directly transmitted between the first microstrip line and the second microstrip line, without the need to realize the transmission of the radio frequency signal through the coupling feeding mode, so as to avoid the loss and unintended radiation caused by the coupling feeding process, and the accuracy and power of the transmitted signal can be improved.

[0008] Correspondingly, the liquid crystal antenna provided by the present disclosure also has the above technical effects. BRIEF DESCRIPTION OF DRAWINGS

[0009] The accompanying drawings, which are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure and, together with the specification, serve to explain the principles of the present disclosure.

[0010] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, those skilled in the art can obtain other drawings according to these drawings without any creative labor.

[0011] Figure 1 is a structural schematic diagram of a liquid crystal phase shifter in the related art; Figure 2 is a structural schematic diagram of a liquid crystal phase shifter provided by the present disclosure; Figure 3 is a structural schematic diagram of another liquid crystal phase shifter provided by the present disclosure; Figure 4 is Figure 2 is a planar schematic diagram of part A in the liquid crystal phase shifter; Figure 5 is a structural schematic diagram of still another liquid crystal phase shifter provided by the present disclosure; Figure 6 is Figure 2 Another plan view of the A part of the liquid crystal phase shifter is shown in the figure. Figure 7 A structural schematic diagram of still another liquid crystal phase shifter provided by the present disclosure is shown in the figure. Figure 8 A structural schematic diagram of still another liquid crystal phase shifter provided by the present disclosure is shown in the figure. DETAILED DESCRIPTION

[0012] In order to enable a more clear understanding of the above-mentioned purposes, features and advantages of the present disclosure, the solutions of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0013] In the following description, a lot of specific details are set forth in order to give a thorough understanding of the present disclosure, but the present disclosure can also be implemented in other manners different from those described herein; obviously, the embodiments described in the specification are only a part of the embodiments of the present disclosure, and not all the embodiments.

[0014] In view of the problem of large coupling feeding loss of the liquid crystal phase shifter in the related art, the inventors have made the following research on the liquid crystal phase shifter in the related art, referring to Figure 1 , Figure 1 A structural schematic diagram of a liquid crystal phase shifter in the related art is shown in the figure, the liquid crystal phase shifter comprises a first substrate 1 and a second substrate 3 arranged oppositely, a liquid crystal layer 5 is arranged between the first substrate 1 and the second substrate 3, a microstrip line 2 is arranged on the side of the first substrate 1 close to the second substrate 3, a feeding waveguide 7 is arranged on the side of the first substrate 1 away from the second substrate 3, a ground layer 4 is arranged on the side of the second substrate 3 close to the first substrate 1, and a radiator 6 is arranged on the side of the second substrate 3 away from the first substrate 1. When the radio frequency signal is transmitted, it is first coupled and fed to the microstrip line 2 through the feeding waveguide 7, at this time the radio frequency signal needs to pass through the first substrate 1, and the radio frequency signal will produce loss and unintended radiation in the process of being coupled to the microstrip line 2. Then the radio frequency signal is coupled and fed to the radiator 6 from the microstrip line 2 through the liquid crystal layer 5, the ground layer 4 and the second substrate 3, and loss and unintended radiation will also be produced in this process. Due to the production of unintended radiation, the accuracy of the transmitted signal will be affected, and since the radio frequency signal loss is large, the transmitted signal power is reduced, and the radiation power is difficult to improve.

[0015] Based on this, the present disclosure provides a liquid crystal phase shifter and a liquid crystal antenna, which are beneficial to reduce radiation loss and unintended radiation, and improve the accuracy and power of the transmitted signal.

[0016] The liquid crystal phase shifter and the liquid crystal antenna provided by the embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0017] Figure 2is a structural schematic diagram of a liquid crystal phase shifter provided by the present disclosure, referring to Figure 2 The present embodiment provides a liquid crystal phase shifter, which comprises a liquid crystal cell 100 and a radio frequency substrate 200. The liquid crystal cell 100 comprises a first substrate 110 and a second substrate 120 arranged oppositely, a liquid crystal layer 130 between the first substrate 110 and the second substrate 120, a first microstrip line 140 on a side of the first substrate 110 facing the second substrate 120, and a first metal layer 150 on a side of the second substrate 120 facing the first substrate 110, the first metal layer 150 being grounded. The radio frequency substrate 200 comprises a third substrate 210 and a second microstrip line 220 on a side of the third substrate 210. A connecting structure 300, the first microstrip line 140 is electrically connected with the second microstrip line 220 through the connecting structure 300.

[0018] Specifically, the liquid crystal phase shifter provided by the present embodiment comprises the liquid crystal cell 100, wherein the liquid crystal cell 100 comprises the first substrate 110 and the second substrate 120 arranged oppositely, and the liquid crystal layer 130 between the first substrate 110 and the second substrate 120, the liquid crystal layer 130 comprising a plurality of liquid crystal molecules, i.e. the first substrate 110 and the second substrate 120 arranged oppositely form a sealed space to accommodate the liquid crystal layer 130. It can be understood that the materials of the first substrate 110 and the second substrate 120 can be set by those skilled in the art according to actual conditions, for example, the first substrate 110 and the second substrate 120 can be any one of glass, ceramic, or any one of polyimide, silicon nitride, and the present disclosure does not make specific limitation thereto.

[0019] The liquid crystal cell 100 further comprises the first microstrip line 140 and the first metal layer 150, the first microstrip line 140 being on a side of the first substrate 110 facing the second substrate 120, and the first metal layer 150 being on a side of the second substrate 120 facing the first substrate 110, the first metal layer 150 being grounded, the first microstrip line 140 being used for transmitting a bias signal while transmitting a radio frequency signal, the bias voltage in the first microstrip line 140 and the ground potential of the first metal layer 150 forming an electric field to control the deflection of the liquid crystal molecules in the liquid crystal layer 130, so as to change the dielectric constant of the liquid crystal molecules, the radio frequency signal realizing phase shift in the liquid crystal layer 130, and achieving the effect of changing the microwave phase.

[0020] The liquid crystal phase shifter further comprises a radio frequency substrate 200 and a connecting structure 300, the radio frequency substrate 200 comprises a third substrate 210 and a second microstrip line 220 located on one side of the third substrate 210, and the first microstrip line 140 can be electrically connected with the second microstrip line 220 through the connecting structure 300, so that the radio frequency signal on the first microstrip line 140 can be directly transmitted to the second microstrip line 220, or the radio frequency signal on the second microstrip line 220 can be directly transmitted to the first microstrip line 140, that is, the radio frequency signal can be directly transmitted between the first microstrip line 140 and the second microstrip line 220, without the need to realize the transmission of the radio frequency signal through the coupling feeding mode, which can avoid the loss and unintended radiation caused by the coupling feeding process, and is beneficial to improve the accuracy and power of the transmitted signal.

[0021] It should be noted that the size of the liquid crystal box 100 and the size of the radio frequency substrate 200 are not specifically limited in the present disclosure, and the size of the liquid crystal box 100 and the size of the radio frequency substrate 200 can be the same or different, the size of the liquid crystal box 100 can be greater than the size of the radio frequency substrate 200, or the size of the liquid crystal box 100 can be smaller than the size of the radio frequency substrate 200, which can be set according to actual needs, and the present disclosure will not be repeated here.

[0022] Continuing to refer to Figure 2 In some optional embodiments, the radio frequency substrate 200 is a radiator unit or a feed waveguide.

[0023] Specifically, the radio frequency substrate 200 can be a radiator unit, that is, the radiator unit can be set in the setting mode of the radio frequency substrate 200, that is, the second microstrip line 220 in the radiator unit is electrically connected with the first microstrip line 140 through the connecting structure 300. The first microstrip line 140 is used to transmit the bias signal while transmitting the radio frequency signal, and the bias voltage in the first microstrip line 140 and the ground potential of the first metal layer 150 form an electric field that controls the deflection of the liquid crystal molecules in the liquid crystal layer 130, thereby changing the dielectric constant of the liquid crystal molecules, and the radio frequency signal is phase-shifted in the liquid crystal layer 130. The radio frequency signal can be directly transmitted to the second microstrip line 220 in the radiator unit after phase shifting, without the need to realize the transmission of the radio frequency signal through the coupling feeding mode, which can avoid the loss and unintended radiation caused by the coupling feeding process, and is beneficial to improve the accuracy and power of the transmitted signal.

[0024] Similarly, the radio frequency substrate 200 can also be a feed waveguide, that is, the feed waveguide can be set in the setting mode of the radio frequency substrate 200, that is, the second microstrip line 220 in the feed waveguide is electrically connected with the first microstrip line 140 through the connecting structure 300. The radio frequency signal on the second microstrip line 220 in the feed waveguide can be directly transmitted to the first microstrip line 140, without the need to realize the transmission of the radio frequency signal through the coupling feeding mode, which can avoid the loss and unintended radiation caused by the coupling feeding process, and is beneficial to improve the accuracy and power of the transmitted signal.

[0025] Figure 3 This is a schematic diagram of another liquid crystal phase shifter provided in this disclosure, for reference. Figure 3 Both the feed waveguide 2001 and the radiator unit 2002 can be configured using the same method as the radio frequency substrate 200. The feed waveguide 2001 and the radiator unit 2002 can be disposed opposite each other at both ends of the liquid crystal cell 100. That is, the second microstrip line 220 in the feed waveguide 2001 is electrically connected to the first microstrip line 140 through the connection structure 300, and the second microstrip line 220 in the radiator unit 2002 is also electrically connected to the first microstrip line 140 through the connection structure 300. The radio frequency (RF) signal on the second microstrip line 220 in the feed waveguide can be directly transmitted to the first microstrip line 140. The first microstrip line 140 is used to transmit the bias signal while transmitting the RF signal. The bias voltage in the first microstrip line 140 and the ground potential of the first metal layer 150 form an electric field that controls the deflection of the liquid crystal molecules in the liquid crystal layer 130, thereby changing the dielectric constant of the liquid crystal molecules. The RF signal is phase-shifted in the liquid crystal layer 130. After phase shifting, the RF signal can be directly transmitted to the second microstrip line 220 in the radiator unit. The RF signal can be transmitted without the need for coupling feed, which avoids the loss and unintended radiation caused by the coupling feed process and helps to improve the accuracy and power of the transmitted signal.

[0026] Figure 4 yes Figure 2 A planar schematic diagram of part A in the liquid crystal phase shifter, for reference. Figure 2 and Figure 4 In some alternative embodiments, the first substrate 110 includes a first main body portion 111 and a first step portion 112 connected to each other, and the first step portion 112 and the second substrate 120 do not overlap in a direction perpendicular to the plane of the first substrate 110. The liquid crystal cell 100 also includes a first pad P1 electrically connected to the first microstrip line 140. The first pad P1 is located on the side of the first step portion 112 facing the second substrate 120, and the first microstrip line 140 is located on the side of the first main body portion 111 facing the second substrate 120. The radio frequency substrate 200 also includes a second pad P2 electrically connected to the second microstrip line 220; The first pad P1 and the second pad P2 are electrically connected through the connection structure 300.

[0027] Specifically, the first substrate 110 includes a first main body portion 111 and a first stepped portion 112 connected to each other. The first main body portion 111 is disposed opposite to the second substrate 120 along a direction perpendicular to the plane of the first substrate 110, and the first main body portion 111 and the second substrate 120 at least partially overlap. The first microstrip line 140 is located on the side of the first main body portion 111 facing the second substrate 120. Thus, the bias voltage in the first microstrip line 140 and the ground potential of the first metal layer 150 can form an electric field that controls the deflection of liquid crystal molecules in the liquid crystal layer 130, thereby changing the dielectric constant of the liquid crystal molecules.

[0028] The liquid crystal cell 100 also includes a first pad P1 electrically connected to the first microstrip line 140. The first pad P1 is located on the side of the first step portion 112 facing the second substrate 120. The radio frequency substrate 200 also includes a second pad P2 electrically connected to the second microstrip line 220. The first pad P1 and the second pad P2 are electrically connected through a connection structure 300. Along the direction perpendicular to the plane of the first substrate 110, the first step portion 112 and the second substrate 120 do not overlap, so the second substrate 120 does not affect the setting of the connection structure 300, and thus the second substrate 120 does not affect the electrical connection between the first pad P1 and the second pad P2, which facilitates the electrical connection between the first microstrip line 140 and the second microstrip line 220.

[0029] Optionally, the first step portion 112 can also be used to bond a circuit board (not shown in the figure). A pad electrically connected to the first microstrip line 140 can also be provided on the side of the first step portion 112 facing the second substrate 120. The circuit board transmits a bias signal to the first microstrip line 140 through this pad. Optionally, a driver chip can also be directly bonded to the first step portion 112, which will not be described in detail here.

[0030] Optionally, a sealing structure 400 may be provided between the first substrate 110 and the second substrate 120, forming a sealed space between them. Optionally, a conductive structure may be provided in the sealing structure 400; for example, conductive gold balls may be provided, but other structures are also possible, without specific limitations, as long as they can transmit a fixed potential. Optionally, the sealing structure 400 may be a frame adhesive.

[0031] The first step portion 112 may also be provided with a pad that is electrically connected to the first metal layer 150 on the side facing the second substrate 120. The first metal layer 150 and the pad can be electrically connected through a conductive structure, and the circuit board transmits a ground signal to the first metal layer 150 through the pad.

[0032] Continue to refer to Figure 2 and Figure 4In some alternative embodiments, the third substrate 210 includes a second body portion 211 and a second step portion 212 connected to each other, the second microstrip line 220 is located on one side of the second body portion 211, and the second pad P2 is located on one side of the second step portion 212. The second step portion 212 and the first step portion 112 are disposed opposite to each other. The first pad P1 is located on the side of the first step portion 112 facing the second step portion 212, and the second pad P2 is located on the side of the second step portion 212 facing the first step portion 112. The connection structure 300 includes solder balls 310, and the first pad P1 and the second pad P2 are electrically connected through the solder balls 310.

[0033] Specifically, the third substrate 210 includes a second main body portion 211 and a second stepped portion 212 connected to each other. The second microstrip line 220 is located on one side of the second main body portion 211, and the second pad P2 is located on one side of the second stepped portion 212. The second microstrip line 220 and the second pad P2 are electrically connected. The second stepped portion 212 can be disposed opposite to the first stepped portion 112, so that the first pad P1 is located on the side of the first stepped portion 112 facing the second stepped portion 212, and the second pad P2 is located on the side of the second stepped portion 212 facing the first stepped portion 112. The first pad P1 and the second pad P2 are disposed opposite to each other, so that the first pad P1 and the second pad P2 can be electrically connected through solder balls 310, thereby facilitating the electrical connection between the first microstrip line 140 and the second microstrip line 220.

[0034] It should be noted that when the first pad P1 and the second pad P2 are electrically connected through solder balls 310, the second main body portion 211 may not overlap with the first main body portion 111 in the direction perpendicular to the plane of the first substrate 110. In this case, the second main body portion 211 is located on the side of the second step portion 212 away from the first main body portion 111, which helps to reduce the overall thickness of the liquid crystal phase shifter. In other embodiments of this disclosure, refer to... Figure 5 , Figure 5 This is a schematic diagram of another liquid crystal phase shifter provided in this disclosure. When the first pad P1 and the second pad P2 are electrically connected by solder balls 310, the second main body 211 can at least partially overlap with the first main body 111 in a direction perpendicular to the plane of the first substrate 110. At this time, the radio frequency substrate 200 can be located on the side of the second substrate 120 away from the first substrate 110. This is beneficial to reduce the overall length of the liquid crystal phase shifter, which will not be described in detail here.

[0035] Continue to refer to Figure 2 and Figure 4In some alternative embodiments, the liquid crystal cell 100 further includes a third pad P3 electrically connected to the first metal layer 150, the third pad P3 being located on the side of the first step portion 112 facing the second step portion 212. The radio frequency substrate 200 also includes a second metal layer 230 and a fourth pad P4 that are electrically connected. The fourth pad P4 is located on the side of the second step portion 212 facing the first step portion 112. The third pad P3 and the fourth pad P4 are electrically connected via solder ball 310.

[0036] Specifically, a third pad P3 is provided on the side of the first step portion 112 facing the second step portion 212. The third pad P3 is electrically connected to the first metal layer 150. The RF substrate 200 also includes a second metal layer 230 and a fourth pad P4 that are electrically connected. The fourth pad P4 is located on the side of the second step portion 212 facing the first step portion 112. The second step portion 212 can be arranged opposite to the first step portion 112. Correspondingly, the third pad P3 and the fourth pad P4 are arranged opposite to each other. Thus, the third pad P3 and the fourth pad P4 can also be electrically connected through solder balls 310, thereby realizing the electrical connection between the second metal layer 230 and the first metal layer 150. Thus, the second metal layer 230 is also grounded, so that the RF signal can be transmitted through the second metal layer 230 and the second microstrip line 220.

[0037] Figure 6 yes Figure 2 Another planar schematic diagram of part A in the liquid crystal phase shifter, see reference. Figure 2 and Figure 6 In some optional embodiments, the liquid crystal cell 100 further includes a first power supply waveguide CPW1, which is located on the side of the first step portion 112 facing the second step portion 212. The first microstrip line 140 and the first metal layer 150 are electrically connected to the first pad P1 and the third pad P3 respectively through the first power supply waveguide CPW1. The RF substrate 200 also includes a second power supply waveguide CPW2, which is located on the side of the second step portion 212 facing the first step portion 112. The second microstrip line 220 and the second metal layer 230 are electrically connected to the second pad P2 and the fourth pad P4 respectively through the second power supply waveguide CPW2.

[0038] Specifically, a first power supply waveguide CPW1 is provided on the side of the first step portion 112 facing the second step portion 212. The first microstrip line 140 and the first metal layer 150 can be electrically connected to the first pad P1 and the third pad P3 respectively through the first power supply waveguide CPW1. The first power supply waveguide CPW1 has good electromagnetic shielding properties, which can reduce electromagnetic radiation to the outside. Similarly, a second power supply waveguide CPW2 is provided on the side of the second step portion 212 facing the first step portion 112. The second microstrip line 220 and the second metal layer 230 can be electrically connected to the second pad P2 and the fourth pad P4 respectively through the second power supply waveguide CPW2. The second power supply waveguide CPW2 also has good electromagnetic shielding properties, which can reduce electromagnetic radiation to the outside. That is, the setting of the first power supply waveguide CPW1 and the second power supply waveguide CPW2 can further reduce the loss and unintended radiation of radio frequency signals during transmission, which is beneficial to improving the accuracy and power of the transmitted signal.

[0039] Figure 7 This is a schematic diagram of another liquid crystal phase shifter provided in this disclosure, for reference. Figure 7 In some alternative embodiments, the connection structure 300 includes a flexible connection structure 320, through which the first pad P1 and the second pad P2 are electrically connected.

[0040] Specifically, the connection structure 300 includes a flexible connection structure 320, which can be bent. One end of the flexible connection structure 320 is electrically connected to the first pad P1, and the other end is electrically connected to the second pad P2. That is, the first pad P1 and the second pad P2 are electrically connected through the flexible connection structure 320. Thus, during the assembly process, the flexible connection structure 320 provides a certain positional tolerance, and the first pad P1 and the second pad P2 do not need to be precisely aligned, reducing the assembly accuracy requirements and improving the production yield.

[0041] Continue to refer to Figure 7 In some alternative embodiments, the flexible connection structure 320 includes a flexible circuit board. The flexible circuit board can be made of polyimide or polyester film as a substrate and is flexible. It also features high wiring density, light weight, and thinness.

[0042] It should be noted that in other embodiments of this disclosure, the flexible connection structure 320 may also adopt other flexible connection structures as needed, which will not be described in detail here.

[0043] Continue to refer to Figure 7 In some alternative embodiments, the radio frequency substrate 200 further includes a second metal layer 230, which is located on the side of the third substrate 210 away from the second microstrip line 220 and is floating.

[0044] Specifically, a second metal layer 230 is disposed on the side of the third substrate 210 opposite to the second microstrip line 220. The second metal layer 230 is floating, meaning it is not electrically directly connected to any signal line or system ground. Radio frequency signals can be transmitted through the second metal layer 230 and the second microstrip line 220. Furthermore, there is no need for a connection structure to connect the second metal layer 230 to the liquid crystal cell 100, effectively reducing assembly difficulty and production costs.

[0045] Continue to refer to Figure 7 In some alternative embodiments, the radio frequency substrate 200 is located on the side of the first pad P1 away from the first step portion 112, and the second pad P2 is located on the side of the third substrate 210 facing the first pad P1.

[0046] Specifically, the RF substrate 200 can be disposed on the side of the first pad P1 away from the first step portion 112. At this time, the second pad P2 can be disposed on the side of the third substrate 210 facing the first pad P1, thereby facilitating the electrical connection between the first pad P1 and the second pad P2 through the flexible connection structure 320.

[0047] Optionally, along a direction perpendicular to the plane of the first substrate 110, the radio frequency substrate 200 may at least partially overlap with the first main body portion 111. In this case, the radio frequency substrate 200 may be located on the side of the second substrate 120 away from the first substrate 110, which is beneficial for reducing the overall length of the liquid crystal phase shifter. Of course, in other embodiments of this disclosure, along a direction perpendicular to the plane of the first substrate 110, the radio frequency substrate 200 may also be configured not to overlap with the first main body portion 111, which will not be described in detail here.

[0048] Figure 8 This is a schematic diagram of another liquid crystal phase shifter provided in this disclosure, for reference. Figure 8 In some alternative embodiments, the radio frequency substrate 200 is located on the side of the first step portion 112 away from the first pad P1, and the second pad P2 is located on the side of the third substrate 210 facing the first step portion 112.

[0049] Specifically, the RF substrate 200 can be located on the side of the first step portion 112 away from the first pad P1. At this time, the second pad P2 is located on the side of the third substrate 210 facing the first step portion 112, thereby facilitating the electrical connection between the first pad P1 and the second pad P2 through the flexible connection structure 320.

[0050] Optionally, along a direction perpendicular to the plane of the first substrate 110, the radio frequency substrate 200 may at least partially overlap with the first main body portion 111. In this case, the radio frequency substrate 200 may be located on the side of the first substrate 110 away from the second substrate 120, which is beneficial for reducing the overall length of the liquid crystal phase shifter. Of course, in other embodiments of this disclosure, along a direction perpendicular to the plane of the first substrate 110, the radio frequency substrate 200 may also be configured not to overlap with the first main body portion 111, which will not be described in detail here.

[0051] This embodiment also provides a liquid crystal antenna, including the liquid crystal phase shifter provided in the above embodiments. The liquid crystal antenna provided in this embodiment has the same technical features as the liquid crystal phase shifter provided in the above embodiments, so it can also solve the same technical problems and achieve the same technical effects.

[0052] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0053] The above description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A liquid crystal phase shifter, characterized in that, include: LCD cell and RF substrate; The liquid crystal cell includes a first substrate and a second substrate disposed opposite to each other, a liquid crystal layer located between the first substrate and the second substrate, a first microstrip line and a first metal layer, wherein the first microstrip line is located on the side of the first substrate facing the second substrate, the first metal layer is located on the side of the second substrate facing the first substrate, and the first metal layer is grounded. The radio frequency substrate includes a third substrate and a second microstrip line located on one side of the third substrate; A connection structure is provided, through which the first microstrip line is electrically connected to the second microstrip line.

2. The liquid crystal phase shifter according to claim 1, characterized in that, The radio frequency substrate is a radiating element or a feed waveguide.

3. The liquid crystal phase shifter according to claim 1, characterized in that, The first substrate includes a first main body portion and a first stepped portion connected to each other. Along a direction perpendicular to the plane where the first substrate is located, the first stepped portion and the second substrate do not overlap. The liquid crystal cell further includes a first pad electrically connected to the first microstrip line. The first pad is located on the side of the first stepped portion facing the second substrate, and the first microstrip line is located on the side of the first main body portion facing the second substrate. The radio frequency substrate also includes a second pad electrically connected to the second microstrip line; The first pad and the second pad are electrically connected through the connection structure.

4. The liquid crystal phase shifter according to claim 3, characterized in that, The third substrate includes a second main body portion and a second stepped portion connected to each other, the second microstrip line is located on one side of the second main body portion, and the second pad is located on one side of the second stepped portion; The second step portion and the first step portion are disposed opposite to each other, the first pad is located on the side of the first step portion facing the second step portion, and the second pad is located on the side of the second step portion facing the first step portion; The connection structure includes solder balls, and the first pad and the second pad are electrically connected through the solder balls.

5. The liquid crystal phase shifter according to claim 4, characterized in that, The liquid crystal cell further includes a third pad electrically connected to the first metal layer, the third pad being located on the side of the first stepped portion facing the second stepped portion; The radio frequency substrate further includes a second metal layer and a fourth pad that are electrically connected, the fourth pad being located on the side of the second step portion facing the first step portion; The third pad and the fourth pad are electrically connected via the solder ball.

6. The liquid crystal phase shifter according to claim 5, characterized in that, The liquid crystal cell further includes a first power supply waveguide, which is located on the side of the first step portion facing the second step portion. The first microstrip line and the first metal layer are electrically connected to the first pad and the third pad respectively through the first power supply waveguide. The radio frequency substrate further includes a second power supply waveguide, which is located on the side of the second step portion facing the first step portion. The second microstrip line and the second metal layer are electrically connected to the second pad and the fourth pad respectively through the second power supply waveguide.

7. The liquid crystal phase shifter according to claim 3, characterized in that, The connection structure includes a flexible connection structure, through which the first pad and the second pad are electrically connected.

8. The liquid crystal phase shifter according to claim 7, characterized in that, The flexible connection structure includes a flexible circuit board.

9. The liquid crystal phase shifter according to claim 7, characterized in that, The radio frequency substrate further includes a second metal layer, which is located on the side of the third substrate away from the second microstrip line and is floating.

10. The liquid crystal phase shifter according to claim 7, characterized in that, The radio frequency substrate is located on the side of the first pad away from the first step portion, and the second pad is located on the side of the third substrate facing the first pad.

11. The liquid crystal phase shifter according to claim 7, characterized in that, The radio frequency substrate is located on the side of the first stepped portion away from the first pad, and the second pad is located on the side of the third substrate facing the first stepped portion.

12. A liquid crystal antenna, characterized in that, The liquid crystal antenna includes the liquid crystal phase shifter according to any one of claims 1-11.

Images