Antenna unit and antenna array

Abstract

The embodiment of the invention provides an antenna unit and an antenna array, the working frequency band of the antenna unit is 18.7 GHz to 20.2 GHz, and the antenna unit comprises an antenna layer which comprises a plurality of antenna bodies; the phase shifter comprises an antenna ground layer, a liquid crystal layer and a phase shifting layer, the antenna ground layer is arranged on one side of the antenna layer, the liquid crystal layer is arranged on the side, away from the antenna layer, of the antenna ground layer, the phase shifting layer is arranged on the side, away from the antenna layer, of the liquid crystal layer, and the box thickness of the liquid crystal layer ranges from 13 micrometers to 18 micrometers. Compared with an electronic phased-array antenna, the liquid crystal phased-array antenna provided by the embodiment of the invention has the advantages that the phase shifting function is realized by utilizing rotation of liquid crystal molecules, a large number of phase shifter chips and transceiving components are omitted, the hardware cost is greatly reduced, the box thickness of the liquid crystal layer can be matched with the production process of an existing liquid crystal display panel, mass production can be realized, and the production efficiency is improved. Therefore, the manufacturing cost of the ground terminal antenna is reduced.

Description

Technical Field

[0001] The present application belongs to the field of antenna technology, and in particular relates to an antenna unit and an antenna array. Background Art

[0002] At present, the deployment of base stations in cities is relatively dense, and the base station network is relatively complete, which provides greater convenience for people's daily lives. However, areas far away from cities, such as remote areas such as the sea, islands, deserts, and Gobi, are not covered by base station networks. In response to the situation where there is no Internet coverage in remote areas, the existing improvement plan is to use low-orbit satellites as relay nodes, and the Internet signal of the ground station is relayed to the ground terminal through the low-orbit satellite. The ground terminal then converts the Internet signal from the satellite into a wifi signal, and the user's smartphone, tablet, laptop and other devices are connected to the wifi to access the Internet. This improvement plan meets the advantages of high speed and light weight of the ground terminal. However, the existing low-orbit satellite ground terminal antenna solution adopts the traditional electronic phased array antenna solution, which contains a large number of phase shifter chips and transceiver components, resulting in the cost of the ground terminal being very expensive. Summary of the Invention

[0003] The present application provides an antenna unit and an antenna array, which can reduce the cost of ground terminals.

[0004] In a first aspect, an embodiment of the present application provides an antenna unit, wherein the operating frequency band of the antenna unit is 18.7 GHz to 20.2 GHz, and the antenna unit includes:

[0005] An antenna layer, comprising a plurality of antenna bodies;

[0006] The phase shifter includes an antenna ground layer, a liquid crystal layer, and a phase shift layer. The antenna ground layer is arranged on one side of the antenna layer, the liquid crystal layer is arranged on the side of the antenna ground layer facing away from the antenna layer, and the phase shift layer is arranged on the side of the liquid crystal layer facing away from the antenna layer. The cell thickness of the liquid crystal layer ranges from 13 microns to 18 microns.

[0007] Optionally, the phase-shifting layer includes a plurality of functional components, each of which includes:

[0008] Slow-wave branch structures, each of the slow-wave branch structures is arranged corresponding to each of the antenna bodies;

[0009] A bias line is connected to the slow-wave branch structure, and the bias line is used to provide direct current to the slow-wave branch structure.

[0010] Optionally, each of the functional components further includes a delay line, wherein the delay line is connected to an end of the slow-wave branch structure away from the bias line.

[0011] Optionally, the number of the functional parts is four, and the four functional parts are symmetrical in pairs.

[0012] Optionally, the antenna unit also includes a power divider layer, which is arranged between the antenna layer and the phase shifter, and the power divider layer includes an input branch, a first output branch and a second output branch, and the first output branch and the second output branch are connected and commonly connected to the input branch.

[0013] Optionally, the first output branch and the second output branch have a phase difference of 180°; and / or

[0014] The thickness of the power divider layer is 12 microns.

[0015] Optionally, the antenna ground layer is provided with a first coupling slot, and the power divider layer and the phase shift layer are coupled through the first coupling slot; and / or

[0016] The antenna stratum is further provided with a plurality of second coupling slots, and each of the antenna bodies is coupled to each of the slow-wave branch structures through each of the second coupling slots.

[0017] Optionally, the antenna stratum is further provided with a plurality of third coupling slots, and each of the slow-wave branch structures is coupled to the antenna stratum through each of the third coupling slots.

[0018] Optionally, the length and width of the antenna unit are 23.3 mm and 21.8 mm, and the thickness of the antenna unit ranges from 0.9 mm to 1 mm; and / or

[0019] The gain of the antenna unit is 5dBi.

[0020] In a second aspect, an embodiment of the present application further provides an antenna array, comprising antenna units as described in any one of the above items distributed in an array.

[0021] In the antenna unit and antenna array of the embodiment of the present application, compared with the electronic phased array antenna, the liquid crystal phased array antenna of the embodiment of the present application uses the rotation of liquid crystal molecules to achieve the phase shift function, eliminating a large number of phase shifter chips and transceiver components, greatly reducing hardware costs, and the box thickness of the liquid crystal layer can match the existing production process of liquid crystal display panels, and can be mass-produced, thereby reducing the production cost of ground terminal antennas. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] To more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0023] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings. In the following description, the same reference numerals represent the same parts.

[0024] Figure 1 A schematic structural diagram of an antenna unit provided in an embodiment of the present application.

[0025] Figure 2 This is another structural schematic diagram of the antenna unit provided in an embodiment of the present application.

[0026] Figure 3 This is another structural schematic diagram of the antenna unit provided in an embodiment of the present application.

[0027] Figure 4 This is a schematic structural diagram of a power divider layer in an antenna unit provided in an embodiment of the present application.

[0028] Figure 5 A schematic diagram of an exploded structure of the antenna unit provided in an embodiment of the present application.

[0029] Figure 6 A schematic structural diagram of an antenna formation in an antenna unit provided in an embodiment of the present application.

[0030] Figure 7 A schematic diagram of the local structure of the third coupling slot in the antenna formation provided in an embodiment of the present application.

[0031] Figure 8 This is a schematic structural diagram of a phase shift layer in an antenna unit provided in an embodiment of the present application.

[0032] Figure 9 This is a schematic structural diagram of the slow-wave branch structure in the phase-shift layer provided in an embodiment of the present application.

[0033] Figure 10 A resonance diagram of the antenna unit provided in an embodiment of the present application.

[0034] Figure 11 The radiation efficiency and total efficiency diagram of the antenna unit provided in the embodiment of the present application.

[0035] Figure 12 This is a gain-frequency curve diagram of the antenna unit provided in an embodiment of the present application.

[0036] Figure 13 This is a structural diagram of another power divider layer in the antenna unit provided in an embodiment of the present application.

[0037] Figure 14 This is a schematic structural diagram of another antenna formation in the antenna unit provided in an embodiment of the present application.

[0038] Figure 15 This is a schematic structural diagram of another phase shift layer in the antenna unit provided in an embodiment of the present application.

[0039] Figure 16 This is another resonance diagram of the antenna unit provided in an embodiment of the present application.

[0040] Figure 17 The gain frequency curves of the normal direction and ±45° of the antenna unit provided in the embodiment of the present application. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0042] Nowadays, cities boast dense base station deployments and well-developed base station networks, providing significant convenience for daily life. However, remote areas far from cities, such as those at sea, on islands, in deserts, and in the Gobi Desert, lack base station network coverage. This creates significant inconvenience for people living and working in these areas, who lack internet access. Two solutions exist to address the lack of internet coverage in remote areas. The first involves using ground terminals with parabolic dish antennas to connect to high-orbit satellites. While this approach offers advantages such as high communication speeds, large bandwidth, and high cell capacity, its disadvantages are that the equipment is bulky and cannot be moved, making it unsuitable for mobility. The second solution involves using mobile phones with integrated L-band technology to connect to medium-orbit satellites. While this approach offers advantages such as lightweight and portable devices, its disadvantages are slow communication speeds and limited bandwidth, comparable to 2G (second-generation wireless communication technology). This makes it suitable only for making phone calls and sending and receiving text messages, and falls short of high-speed internet access. Neither of these solutions offers the combined advantages of high data rates and a thin and lightweight design, resulting in a poor user experience.

[0043] Another existing improvement scheme can be described as using low-orbit satellites as relay nodes. The internet signal from the ground station is relayed to the ground terminal via the low-orbit satellite. The ground terminal then converts the internet signal from the satellite into a Wi-Fi signal. People's smartphones, tablets, laptops, and other devices connect to the Wi-Fi and thus access the internet. This improvement scheme meets the advantages of high speed and light weight of the ground terminal. However, the existing low-orbit satellite ground terminal antenna solution uses a traditional electronic phased array antenna solution, which contains a large number of phase shifter chips and transceiver components. This makes the ground terminal very expensive and not user-friendly. Therefore, the existing technology needs further improvement.

[0044] Based on the above problems, an embodiment of the present application provides an antenna unit and an antenna array, which can reduce the cost of ground terminals, and will be described below with reference to the accompanying drawings.

[0045] For example, see Figure 1 As shown, Figure 1 Schematic diagram of the structure of an antenna unit provided in an embodiment of the present application. The operating frequency band of the antenna unit 100 in the embodiment of the present application is the Ka (K-above) band, i.e., 18.7 GHz to 20.2 GHz. The antenna unit 100 includes an antenna layer 110 and a phase shifter 120.

[0046] The antenna layer 110 includes multiple antenna bodies 112. For example, the antenna layer 110 may include four antenna bodies 112, and the four antenna bodies 112 are arranged in a 2×2 array. For another example, the antenna layer 110 may include 16 antenna bodies 112, and the 16 antenna bodies 112 are arranged in a 4×4 array. This is to form a larger antenna array, so that the ground terminal can connect to low-orbit satellites.

[0047] Phase shifter 120 includes an antenna ground layer 121, a liquid crystal layer 122, and a phase shift layer 123. Antenna ground layer 121 is disposed on one side of antenna layer 110, liquid crystal layer 122 is disposed on the side of antenna ground layer 121 facing away from antenna layer 110, and phase shift layer 123 is disposed on the side of liquid crystal layer 122 facing away from antenna layer 110.

[0048] Among them, the box thickness range of the liquid crystal layer 122 is 13 microns to 18 microns. Since the box thickness of the liquid crystal layer is limited to 20 microns during batch production of liquid crystal display panels, the liquid crystal layer 122 of the embodiment of the present application can match the batch production process of liquid crystal display panels, so there is no need to use a separate and complex process to produce the liquid crystal layer 122, which can save production time and production costs.

[0049] It should be noted that the antenna in the embodiment of the present application is a liquid crystal phased array antenna type, which uses the rotation of liquid crystal molecules to achieve the phase shift function. Therefore, there is no need to set up a large number of phase shifter chips and transceiver components like electronic phased array antennas.

[0050] In the antenna unit 100 provided in the embodiment of the present application, compared with the electronic phased array antenna, the liquid crystal phased array antenna in the embodiment of the present application uses the rotation of liquid crystal molecules to achieve the phase shift function, eliminating a large number of phase shifter chips and transceiver components, greatly reducing hardware costs, and the box thickness of the liquid crystal layer can match the existing production process of liquid crystal display panels, enabling mass production, thereby reducing the production cost of ground terminal antennas.

[0051] It should be noted that in related art, to increase the bandwidth of the antenna, antenna bodies are typically provided on opposite sides of the phase shifter, resulting in a relatively thick antenna. The antenna unit 100 of the present embodiment can be reduced in thickness while ensuring bandwidth. This is because the antenna unit 100 of the present embodiment has an antenna layer 110 provided on one side of the phase shifter 120, and the antenna bodies 112 within the antenna layer 110 are arranged in an array. This increases the size of the antenna, thereby ensuring a certain bandwidth.

[0052] Exemplarily, the length and width of the antenna unit 100 can be 23.3 mm and 21.8 mm, and the thickness of the antenna unit 100 ranges from 0.9 mm to 1 mm. In the embodiment of the present application, the thickness of the antenna unit 100 is 0.93 mm as an example, and the structure of the antenna unit 100 will be described in layers below.

[0053] For example, please combine Figure 1 See also Figure 2 As shown, Figure 2 This is another structural schematic diagram of an antenna unit provided in an embodiment of the present application. The thickness of the antenna layer 110 can be 12 microns, and the material of the antenna layer 110 can be a metal material such as copper. Taking the example of the antenna layer 110 including four antenna bodies 112, each antenna body 112 can be a square sheet structure, and the length and width of each antenna body 112 can be 4.15 mm respectively. The four antenna bodies 112 are arranged in an array of two rows and two columns, wherein the distance between the two antenna bodies 112 in each row can be 7.35 mm, and the distance between the two antenna bodies 112 in each column is 7.85 mm.

[0054] See also Figure 3 and Figure 4 , Figure 3 This is another structural diagram of the antenna unit provided in an embodiment of the present application. Figure 4This is a schematic diagram of the structure of a power divider layer in an antenna unit provided in an embodiment of the present application. For example, antenna unit 100 further includes a power divider layer 130. Power divider layer 130 is disposed between antenna layer 110 and phase shifter 120. For example, power divider layer 130 may be 12 microns thick and may be made of a metal material such as copper. The power divider may be configured to have a bifurcated structure, i.e., one input port and two output ports, with the two output ports maintaining a 180° phase difference.

[0055] Exemplarily, the power divider layer 130 includes an input branch 131, a first output branch 132, and a second output branch 133. The first output branch 132 and the second output branch 133 are connected and commonly connected to the input branch 131. The first output branch 132 and the second output branch 133 have a phase difference of 180°. For example, the first output branch 132 and the second output branch 133 are both strips with a set width, such as a width of 0.25 mm, one end of the first output branch 132 is connected to one end of the second output branch 133, and the other end of the first output branch 132 is parallel to the other end of the second output branch 133, and the second output branch 133 is also provided with a bending portion at one end close to the first output branch 132, the distance between the two bending strips in the bending portion is 0.7 mm, and the distance from the top of the bending portion to the bottom thereof is 2.8 mm. The input branch 131 is a strip with two widths, wherein the width of the part close to the first output branch 132 and the second output branch 133 can be 0.55 mm and the length can be 2.35 mm; the width of the part away from the first output branch 132 and the second output branch 133 can be 0.25 mm and the length can be 3 mm.

[0056] Please continue reading Figure 3 Exemplarily, the antenna unit 100 further includes an attachment layer 140, which is disposed between the antenna layer 110 and the power divider layer 130. The attachment layer 140 can serve as a substrate for attaching the two copper layers, the antenna layer 110 and the power divider layer 130, to support and secure the antenna layer 110 and the power divider layer 130. The thickness of the attachment layer 140 can be 200 microns, and the material of the attachment layer 140 can be LCP (Liquid Crystal Polymer), which is a flexible PCB (Printed Circuit Board) dielectric material. The length and width of the attachment layer 140 can be 23.3 mm and 21.8 mm, respectively.

[0057] See also Figure 5 As shown, Figure 5This is a schematic diagram of an exploded structure of an antenna unit provided in an embodiment of the present application. Exemplarily, the antenna unit 100 further includes an adhesive layer 150, which is disposed between the attachment layer 140 and the phase shifter 120. The adhesive layer 150 is used to adhere the attachment layer 140 and the phase shifter 120 together. It is understood that since the antenna layer 110 and the power divider layer 130 are attached to the attachment layer 140, the embodiments of the present application illustrate the adhesive layer 150 bonding the attachment layer 140 and the phase shifter 120, and this should not be construed as limiting the adhesive layer 150 or the attachment layer 140.

[0058] The adhesive layer 150 has a thickness of 100 microns and can be made of optically transparent adhesive. To prevent the adhesive from affecting antenna radiation, the adhesive and the metal portion of the liquid crystal phased array antenna do not overlap in the vertical projection direction. For example, the adhesive layer 150 can be shaped like a square ring, with its outer ring dimensions matching those of the antenna unit 100 and its inner ring avoiding the metal portion of the antenna unit 100, leaving the solid portion for bonding.

[0059] Illustratively, the antenna unit 100 further includes a first glass layer 160 and a second glass layer 162. The first glass layer 160 is disposed between the adhesive layer 150 and the phase shifter 120, and the second glass layer 162 is disposed on the side of the phase shifter 120 facing away from the first glass layer 160. In other words, the first glass layer 160 and the second glass layer 162 jointly sandwich the phase shifter 120. In other embodiments, the first glass layer 160 and the second glass layer 162 may also serve as part of the phase shifter 120. For ease of description, the first glass layer 160 and the second glass layer 162 are described as separate from the phase shifter 120, but this should not be construed as limiting the first glass layer 160 and the second glass layer 162.

[0060] The thickness of the first glass layer 160 and the second glass layer 162 can both be 300 microns, the materials of the first glass layer 160 and the second glass layer 162 are both glass, and the length and width of the first glass layer 160 and the second glass layer 162 are both 23.3 mm and 21.8 mm, so that the first glass layer 160 and the second glass layer 162 can be processed together.

[0061] The antenna unit 100 of the embodiment of the present application can achieve a relatively high gain, such as 5 dBi. The high antenna gain is mainly achieved through the structural design of the phase shifter 120. The structure of the phase shifter 120 will be described below.

[0062] Please combine Figure 5 See also Figure 6 and Figure 7 As shown, Figure 6This is a schematic diagram of the structure of an antenna formation in an antenna unit provided in an embodiment of the present application. Figure 7 A schematic diagram of the partial structure of the third coupling slot in the antenna stratum provided in an embodiment of the present application. For example, the thickness of the antenna stratum 121 can be 2.2 microns, and the length and width of the antenna stratum 121 can be 23.3 mm and 21.8 mm, respectively. Slots are distributed in local areas of the antenna stratum 121, while the rest of the antenna stratum 121 is intact. For example, the antenna stratum 121 is provided with a first coupling slot 1210, through which the power divider layer 130 and the phase shift layer 123 are coupled. The number of first coupling slots 1210 can be two, and the two first coupling slots 1210 can be symmetrically arranged in the middle area of the antenna stratum 121. The length and width of each first coupling slot 1210 can be 2 mm and 1.5 mm.

[0063] The antenna substrate 121 is further provided with multiple second coupling slots 1212, for example, four second coupling slots 1212, to match the number of antenna bodies 112. Furthermore, the four second coupling slots 1212 can be arranged in an array, with each first coupling slot 1210 positioned between two second coupling slots 1212 along the length of the antenna substrate 121. Each antenna body 112 is coupled to the corresponding structure of the phase shift layer 123 via each second coupling slot 1212. For example, the length and width of each second coupling slot 1212 can be 3.2 mm and 0.5 mm.

[0064] Exemplarily, the antenna ground layer 121 is further provided with multiple third coupling slots 1214, such as four third coupling slots 1214. Each structure of the phase-shifting layer 123 can be coupled to the antenna ground layer 121 through each third coupling slot 1214. The third coupling slots 1214 can be composed of multiple slots, such as a plurality of slots arranged in a row. Each slot can have a width of 0.04 mm, and the distance between adjacent slots is 0.01 mm, to accommodate the structure of the phase-shifting layer 123. The second coupling slots 1212 can all be located inside the third coupling slots 1214, thereby meeting coupling requirements while ensuring a reasonable arrangement of the coupling slots for easier positioning and fabrication.

[0065] Exemplarily, the liquid crystal layer 122 is a rectangular sheet structure. For example, the thickness of the liquid crystal layer 122 may be 15.6 micrometers, and the length and width dimensions may be 23.3 mm and 21.8 mm.

[0066] Please combine Figure 5 See also Figure 8 and Figure 9 As shown, Figure 8 This is a schematic structural diagram of a phase shift layer in an antenna unit provided in an embodiment of the present application. Figure 9Schematic diagram of the structure of the slow-wave branch structure in the phase-shift layer provided in an embodiment of the present application. Exemplarily, the thickness of the phase-shift layer 123 can be 2.2 microns, and the phase shifters of the phase-shift layer 123 are regularly arranged. For example, the phase-shift layer 123 includes multiple functional components 1230, such as four functional components 1230, to adapt to the antenna body 112. Each functional component 1230 can form a positive and negative pole with the antenna ground layer 121. When different voltages are applied to the positive and negative poles, the liquid crystal molecules between the phase-shift layer 123 and the antenna ground layer 121 will rotate to different angles, thereby changing the dielectric constant of the liquid crystal material, and then changing the propagation speed of the electromagnetic wave in the phase shifter 120, generating different time delay differences, and ultimately achieving the purpose of changing the phase.

[0067] Each functional component 1230 includes a slow-wave branch structure 1232 and a bias line 1234. A slow-wave branch structure is a device used to enhance the interaction between moving electrons and electromagnetic fields. It is primarily used in traveling-wave electronic devices to more efficiently convert the energy of the electron flow into high-frequency energy of electromagnetic waves. To achieve this goal, the electron's travel speed must be close to the phase velocity of the electromagnetic wave, that is, to meet the synchronization condition. Therefore, the design of the slow-wave branch structure needs to slow down the phase velocity of the electromagnetic wave. Therefore, the slow-wave branch structure 1232 of the embodiment of the present application can be fishbone-shaped, that is, a structure formed by connecting a trunk and branches. For example, the overall length and width of the slow-wave branch structure 1232 can be 7.34 mm and 1.14 mm, respectively. The trunk width can be 0.04 mm, the branch width can be 0.04 mm, and the distance between adjacent branches can be 0.06 mm. Each slow-wave branch structure 1232 is arranged corresponding to each antenna body 112, that is, the slow-wave branch structure 1232 can also be arranged in an array. The bias line 1234 is connected to the slow-wave branch structure 1232 , and the bias line 1234 is used to provide direct current to the slow-wave branch structure 1232 .

[0068] The four functional components 1230 can be arranged symmetrically in pairs. For example, each bias line 1234 can be a bent structure, with a bend width of 3.13 mm and a bend length of 6.85 mm. Adjacent bias lines 1234 are symmetrically bent.

[0069] It should be noted that the bias line 1234 can be connected to any point of the slow-wave branch structure 1232. The embodiment of the present application takes the connection between the bias line 1234 and one end of the slow-wave branch structure 1232 as an example, and should not be understood as a limitation on the connection method of the bias line 1234 and the slow-wave branch structure 1232.

[0070] Illustratively, each functional component 1230 further includes a delay line 1236, which connects to the end of the slow-wave branch structure 1232 facing away from the bias line 1234. The delay lines 1236 can be L-shaped, with adjacent delay lines 1236 symmetrically arranged. This ensures symmetry among the four functional components 1230 and facilitates their installation and positioning. Illustratively, the delay lines 1236 extend 1.24 mm along the length of the slow-wave branch structure 1232 and 2.99 mm along the width of the slow-wave branch structure 1232.

[0071] It should be noted that the first coupling slot 1210 , the second coupling slot 1212 and the third coupling slot 1214 all involve the coupling of the slow-wave branch structure 1232 in the phase-shift layer 123 .

[0072] It should be noted that the slow-wave structure has the characteristics of small phase shift and small loss, while the delay line 1236 has the characteristics of large phase shift and large loss. The embodiment of the present application combines the slow-wave branch structure 1232 with the delay line 1236 to achieve the advantages of large phase shift and small loss.

[0073] It should be noted that the core component of the liquid crystal phased array antenna is the liquid crystal phase shifter. The operating principle of the liquid crystal phase shifter is as follows: the phase shifter layer 123 and the antenna ground layer 121 form positive and negative electrodes. By applying different voltages to the positive and negative electrodes, the steering angle of the liquid crystal molecules is changed, thereby changing the dielectric constant of the liquid crystal material, and thus changing the propagation speed of the electromagnetic wave in the phase shifter 120, generating different time delay differences to achieve the purpose of changing the phase. The liquid crystal phase shifter, combined with the array of antenna bodies 112 in the antenna layer 110, forms a liquid crystal phased array antenna. The operating principle of the liquid crystal phased array antenna is as follows: the RF power signal is first fed to the power divider layer 130, which then couples the RF energy to one end of the phase shifter 120. After the RF energy passes through the phase shifter 120, the other end of the phase shifter 120 couples the RF energy to the antenna layer 110, and the RF energy is finally radiated into the air through the antenna.

[0074] According to the stacked structure of the liquid crystal phased array antenna and the size of each layer, the antenna unit 100 is subjected to resonance simulation, as shown in FIG. Figure 10 As shown, Figure 10 This is a resonance diagram of the antenna unit provided by an embodiment of the present application. The resonance depth within the effective bandwidth (18.7 GHz to 20.2 GHz) is greater than -7 dB, indicating good impedance matching.

[0075] like Figure 11 As shown, Figure 11The radiation efficiency and total efficiency diagrams of the antenna unit provided in the embodiment of the present application are shown. Based on the stacked structure and dimensions of each layer of the liquid crystal phased array antenna described above, the radiation efficiency and total efficiency of the antenna unit 100 were simulated. The total efficiency within the effective bandwidth (18.7 GHz to 20.2 GHz) was better than -8 dB, indicating good antenna performance.

[0076] The liquid crystal phase shifter is the core component of the liquid crystal phased array antenna. According to the stacked structure of the liquid crystal phase shifter and the dimensions of each layer, the loss of the liquid crystal phase shifter in the embodiment of the present application is -6.8dB, and the phase shifter is above 410°.

[0077] The liquid crystal phase shifter combined with the antenna array forms a liquid crystal phased array antenna. According to the stacked structure of the liquid crystal phased array antenna and the size of each layer, the gain of the liquid crystal phased array antenna of the embodiment of the present application is as follows: Figure 12 As shown, Figure 12 This is a gain-frequency curve diagram of the antenna unit provided in the embodiment of the present application. It can be seen that the gain within the effective bandwidth (18.7 GHz to 20.2 GHz) is higher than 5 dBi, indicating that the antenna performance is good.

[0078] Based on the 2×2 liquid crystal phased array antenna of the embodiment of the present application, a large array is formed to form a 64×64 array of liquid crystal phased array antenna. The antenna gain can reach 32dBi (taking into account the 3dB loss caused by the array), so that when the ground terminal connects to the low-orbit satellite, it can obtain faster uplink and downlink rates and better call quality.

[0079] The embodiments of the present application propose a design scheme for a liquid crystal phased array antenna. Compared with the electronic phased array antenna scheme, the liquid crystal phased array antenna scheme uses the rotation of liquid crystal molecules to achieve the phase shifting function, eliminating a large number of phase shifter chips and transceiver components, thereby achieving the purpose of cost reduction. Its antenna cost is only 1 / 10 of that of the electronic phased array antenna. The liquid crystal phased array antenna designed in the embodiment of the present application uses a liquid crystal phase shifter with a cell thickness of 15.6um. The operating frequency band is the Ka (K-above, K band above) band, that is, 18.7GHz to 20.2GHz. It has good antenna performance, a gain of more than 5dBi, and an effective bandwidth of 1.5G. It can also match the existing LCD (Liquid Crystal Display) panel production process and can be mass-produced. With a 2×2 antenna body array as the basic unit, a larger antenna array can be formed, allowing ground terminals to connect to low-orbit satellites. For end users, low-orbit satellite ground terminals have the characteristics of low cost, high speed and light weight, providing a good user experience.

[0080] In order to solve the pain point that satellite Internet ground terminals cannot meet the requirements of low cost, high speed and light weight at the same time, the embodiment of the present application proposes a design scheme for a liquid crystal phased array antenna. The liquid crystal phased array antenna in the embodiment of the present application has a size of 23.3 mm × 21.8 mm, a thickness of 0.93 mm, an operating frequency band of Ka band, i.e. 18.7 GHz ~ 20.2 GHz, and an antenna gain of 5 dBi. This antenna solution is based on a liquid crystal phase shifter with a box thickness of 15.6 um, which can be matched with existing LCD production lines for batch production. Compared with electronic phased array antennas, liquid crystal phased array antennas eliminate a large number of phase shifter chips and RF transceiver chips, greatly reducing hardware costs. Based on the 2×2 liquid crystal phased array antenna described in the embodiment of the present application, it can be expanded to a 64×64 liquid crystal phased array antenna, which can simultaneously meet the characteristics of low cost, high speed and light weight of low-orbit satellite ground terminals, and has a good user experience.

[0081] It should be noted that the number of antenna bodies in the antenna layer is not limited to the above-mentioned 2×2 four antenna bodies. When the antenna body is a 4×4 liquid crystal phased array antenna with 16 antenna bodies, the antenna unit can also realize the beam scanning function.

[0082] Exemplarily, the length and width of the antenna unit can be 91 mm and 70 mm, and the thickness of the antenna unit ranges from 0.9 mm to 1 mm. In the embodiment of the present application, the thickness of the antenna unit 100 is 0.92 mm as an example, and the structure of the antenna unit will be described in layers below.

[0083] For example, the antenna layer can be 12 microns thick. The antenna layer includes 16 antenna bodies, each of which can be a square sheet-like structure. The length and width of each antenna body can be 4.15 mm respectively. The 16 antenna bodies are arranged in a four-row, four-column array. The distance between two antenna bodies in each row can be 7.7 mm, and the distance between two antenna bodies in each column can be 5.2 mm.

[0084] For example, see Figure 13 , Figure 13 This is a schematic diagram of the structure of another power divider layer in the antenna unit provided in an embodiment of the present application. Power divider layer 130 is disposed between the antenna layer and the phase shifter. For example, power divider layer 130 can be 12 microns thick and can be made of a metal material such as copper. Power divider layer 130 can be configured to have an eight-way split structure, with one input port and eight output ports, forming four pairs of output ports, each pair maintaining a 180° phase difference.

[0085] For example, the power divider layer 130 includes an input branch 131 and eight output branches 134, wherein the eight output branches 134 form four pairs of output branches, and the two output branches 134 of each pair of output branches have a phase difference of 180 degrees, and each two adjacent pairs of output branches can be symmetrically distributed. Figure 4 The size of the power divider layer 130 in the above embodiment is set, which will not be repeated here.

[0086] The antenna unit also includes an attachment layer, which is disposed between the antenna layer and the power divider layer. The attachment layer can serve as a substrate for attaching the two copper layers, the antenna layer and the power divider layer, to support and secure the antenna layer and the power divider layer. The thickness of the attachment layer can be 200 microns, and the material of the attachment layer can be LCP (Liquid Crystal Polymer), a flexible PCB (Printed Circuit Board) dielectric material with a low dielectric constant and loss tangent. The length and width of the attachment layer can be 80.8 mm and 70 mm, respectively.

[0087] The antenna unit also includes an adhesive layer disposed between the attachment layer and the phase shifter, and is used to bond the attachment layer and the phase shifter together. It is understood that since the antenna layer and the power divider layer are attached to the attachment layer, the embodiments of this application illustrate bonding the attachment layer and the phase shifter using the adhesive layer, and this should not be construed as limiting the adhesive layer or the attachment layer.

[0088] The adhesive layer is 100 microns thick and can be made of optically transparent adhesive. To prevent the adhesive from affecting antenna radiation, the adhesive and the metal portion of the liquid crystal phased array antenna should not overlap in the vertical projection direction. For example, the adhesive layer can be shaped like a square ring, with the outer ring sized to match the size of the antenna unit, the inner ring avoiding the metal portion of the antenna unit, and the solid portion used for bonding.

[0089] The antenna unit also includes a first glass layer and a second glass layer. The first glass layer is disposed between the adhesive layer and the phase shifter, and the second glass layer is disposed on the side of the phase shifter facing away from the first glass layer. In other words, the first and second glass layers together sandwich the phase shifter. In other embodiments, the first and second glass layers may also serve as part of the phase shifter. For ease of description, the first and second glass layers are described as separate from the phase shifter, but this should not be construed as limiting the first and second glass layers.

[0090] The thickness of the first glass layer and the second glass layer can both be 300 microns, the materials of the first glass layer and the second glass layer are both glass, the length and width of the first glass layer are 80.8 mm and 70 mm, and the length and width of the second glass layer are 85.1 mm and 70 mm.

[0091] The antenna unit of the embodiment of the present application can achieve a higher gain. The normal gain of the 4×4 array antenna is 9dBi, and it can achieve a scanning angle of ±45°. Compared with the normal, the gain at the angle of ±45° drops within 6dBi. The high gain and scanning angle of the antenna are mainly achieved through the structural design of the phase shifter. The structure of the phase shifter will be explained below.

[0092] For example, see Figure 14 , Figure 14 This is a schematic diagram of the structure of another antenna layer in the antenna unit provided in the embodiment of the present application. The thickness of the antenna layer 121 can be 2.2 microns, and the length and width of the antenna layer 121 are 49.5 mm and 43 mm respectively. There are gaps in some areas of the antenna layer 121, and the rest of the antenna layer 121 is intact. Figure 6 As a reference, the antenna ground layer 121 of the embodiment of the present application may include four groups such as Figure 6 The antenna ground layer with coupling slots shown in FIG. 1 has 8 first coupling slots 1210, 16 second coupling slots 1212 and 16 third coupling slots 1214. The arrangement of the four groups of coupling slots is as follows: Figure 14 shown.

[0093] Exemplarily, the liquid crystal layer is a rectangular sheet structure. For example, the thickness of the liquid crystal layer may be 15.6 micrometers, and the length and width dimensions may be 49.5 mm and 43 mm.

[0094] For example, see Figure 15 , Figure 15 This is a schematic diagram of the structure of another phase-shifting layer in the antenna unit provided in an embodiment of the present application. The thickness of the phase-shifting layer 123 can be 2.2 microns, and the phase shifters of the phase-shifting layer 123 are arranged in a regular pattern. For example, the phase-shifting layer 123 includes multiple functional components 1230, such as 16 functional components 1230, to adapt to the antenna body. Each functional component 1230 can form a positive and negative pole with the antenna stratum. When different voltages are applied to the positive and negative poles, the liquid crystal molecules between the phase-shifting layer 123 and the antenna stratum will rotate to different angles, thereby changing the dielectric constant of the liquid crystal material, and then changing the propagation speed of the electromagnetic wave in the phase shifter, resulting in different time delay differences, and ultimately achieving the purpose of changing the phase.

[0095] Please refer to Figure 8 and Figure 9As described above, each functional part 1230 includes a slow-wave branch structure 1232 and a bias line 1234. The slow-wave branch structure refers to a device for enhancing the interaction between moving electrons and electromagnetic fields. It is mainly used in traveling-wave electronic devices to more effectively convert the energy of the electron flow into high-frequency energy of electromagnetic waves. In order to achieve this goal, the traveling speed of the electrons must be close to the phase velocity of the electromagnetic wave, that is, the synchronization condition must be met. Therefore, the design of the slow-wave branch structure needs to slow down the phase velocity of the electromagnetic wave. Among them, each slow-wave branch structure 1232 is arranged corresponding to each antenna body, that is, the slow-wave branch structure 1232 can also be arranged in an array. The bias line 1234 is connected to the slow-wave branch structure 1232, and the bias line 1234 is used to provide direct current to the slow-wave branch structure 1232.

[0096] Among them, 16 functional parts 1230 can be grouped into four groups, and divided into four groups. The arrangement of each group of functional parts 1230 can refer to Figure 8 As shown in FIG, the four groups of functional components 1230 may also be arranged in an array.

[0097] Illustratively, each functional component 1230 further includes a delay line 1236, which is connected to the end of the slow-wave branch structure 1232 that faces away from the bias line 1234. The delay line 1236 may be L-shaped, with each adjacent delay line 1236 also symmetrically arranged. This ensures symmetry in the structures of the four functional components 1230 in the four groups, facilitating installation and positioning of the functional components 1230.

[0098] The phase-shifting layer 123 of the present embodiment further includes a main bias line 1231 and an auxiliary bias line 1233. The auxiliary bias line 1233 is used to connect all functional components 1230, and the main bias line 1231 connects to the auxiliary bias line 1233. The main bias line 1231 is in a curved shape. The phase-shifting layer 123 further includes a DC blocking structure 1235, which is disposed between adjacent functional components 1230 to help the bias line block DC.

[0099] It should be noted that the first coupling slot, the second coupling slot and the third coupling slot all involve the coupling of the slow-wave branch structure 1232 in the phase-shift layer 123 .

[0100] It should be noted that the slow-wave structure has the characteristics of small phase shift and small loss, while the delay line 1236 has the characteristics of large phase shift and large loss. The embodiment of the present application combines the slow-wave branch structure 1232 with the delay line 1236 to achieve the advantages of large phase shift and small loss.

[0101] It should be noted that the core component of the liquid crystal phased array antenna is the liquid crystal phase shifter. The working principle of the liquid crystal phase shifter is that the bias line is physically connected to the slow-wave branch structure to form a positive voltage electrode, and the antenna ground layer forms a negative voltage electrode. When different square wave voltages are applied to the positive and negative electrodes, the liquid crystal molecules will rotate to different angles, 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. The liquid crystal layer is divided into four columns, and a different voltage is applied to each column to realize the one-dimensional beam scanning of the liquid crystal phased array antenna.

[0102] The liquid crystal phase shifter combined with the antenna body array in the antenna layer forms a liquid crystal phased array antenna. The working principle of the liquid crystal phased array antenna is that the RF power signal is first fed to the power divider layer, and the power divider layer then couples the RF energy to one end of the phase shifter. After the RF energy passes through the phase shifter, the other end of the phase shifter couples the RF energy to the antenna layer, and finally the RF energy is radiated into the air through the antenna.

[0103] In this embodiment, the liquid crystal material is divided into four columns: A, B, C, and D. Different square wave voltages are applied to the four columns to achieve different dielectric constants (Dk) and loss tangents (Df), enabling a one-dimensional phase scanning system with any angle within ±45°. The following figure illustrates the dielectric constant and loss tangent configurations for the four columns, using 0°, ±15°, and ±45° as examples.

[0104] Table 1 4×4 array LCD parameter configuration table

[0105]

[0106] The performance of liquid crystal phased array antennas is primarily measured by antenna resonance, normal gain, scanning angle, and gain drop-off at maximum scanning angle. The antenna unit in this embodiment can be expanded into a 64×64 antenna array and integrated into a liquid crystal phased array terminal, offering the advantages of high speed, high bandwidth, wide scanning angle, low cost, and low power consumption.

[0107] See also Figure 16 , Figure 16 This is another resonance diagram of the antenna unit provided in the embodiment of the present application. According to the laminated structure of the antenna unit and the size of each layer, the resonance diagram of the liquid crystal phased array antenna in the embodiment of the present application is as follows Figure 16 ,from Figure 16 As can be seen from the figure, the resonance depth within the effective bandwidth (18.7 GHz to 20.2 GHz) is better than -10 dB, indicating good impedance matching. The resonance diagram of the liquid crystal phased array antenna at ±45° is essentially the same as the resonance diagram at normal direction.

[0108] See also Figure 17 , Figure 17 The gain frequency curves for the normal and ±45° directions of the antenna unit provided in the embodiment of the present application are shown in Figure 2. The liquid crystal phase shifter combined with the antenna array forms a liquid crystal phased array antenna. According to the stacked structure of the antenna unit and the dimensions of each layer, the gain frequency curves for the normal and ±45° directions of the liquid crystal phased array antenna in the embodiment of the present application are shown in Figure 2. Figure 17 ,from Figure 17 As can be seen from the figure, the normal gain of the 4×4 liquid crystal phased array antenna is higher than 9 dBi within the effective bandwidth (18.7 GHz to 20.2 GHz), indicating good antenna performance. The scanning range covers ±45°, which is wide. The gain at ±45° is higher than 4 dBi within the effective bandwidth (18.7 GHz to 20.2 GHz). Compared with the normal direction, the gain drops by 4 dBi and 6 dBi at ±45° at 18.7 GHz and 20.2 GHz, respectively, indicating a small gain drop.

[0109] Based on the 4×4 liquid crystal phased array antenna described in this patent, a large array is formed to form a 64×64 array of liquid crystal phased array antenna. The antenna gain can reach 32dBi (taking into account the 3dB loss caused by the array), so that the ground terminal can obtain faster uplink and downlink rates and better call quality when connecting to low-orbit satellites.

[0110] The antenna unit of the embodiment of the present application has a liquid crystal phased array antenna beam scanning system. The size of the 4×4 liquid crystal phased array antenna of the embodiment of the present application is 91 mm × 70 mm × 0.92 mm. It operates in the Ka band, that is, 18.7 GHz to 20.2 GHz. By applying a specific square wave voltage to the liquid crystal molecules, it can achieve ±45° phase scanning. The normal gain is higher than 9dBi, and the gain at ±45° is higher than 4dBi. Compared with the normal direction, the gain drop at ±45° is less than 6dB. Based on the 4×4 liquid crystal phased array antenna described in the embodiment of the present application, a large array is formed to form a 64×64 array of liquid crystal phased array antenna and its ground terminal, so that when the ground terminal is connected to a low-orbit satellite, it can obtain faster uplink and downlink rates and better call quality. In addition, the liquid crystal thickness corresponding to the liquid crystal phased array antenna is 15.6 microns, which can be effectively adapted to the existing LCD panel process production line and can be mass-produced. Compared with the electronic phased array antenna solution, the liquid crystal phased array antenna solution described in the embodiment of the present application has the advantages of low cost and low power consumption, and is more user-friendly.

[0111] The present application also provides an antenna array comprising antenna units distributed in an array. For example, the antenna array may be a 64×64 array structure of antenna units. The structure of the antenna units can refer to the above embodiments and will not be described in detail here. Since the present antenna array utilizes all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought about by the technical solutions of the above embodiments, and will not be described in detail here.

[0112] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0113] In the description of this application, 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. Therefore, features specified as "first" or "second" may explicitly or implicitly include one or more features.

[0114] The above is a detailed introduction to the antenna unit and antenna array provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for technical personnel in this field, based on the ideas of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. An antenna unit, characterized in that: The operating frequency band of the antenna unit is 18.7 GHz to 20.2 GHz, and the antenna unit includes: An antenna layer, comprising a plurality of antenna bodies; The phase shifter includes an antenna ground layer, a liquid crystal layer, and a phase shift layer. The antenna ground layer is arranged on one side of the antenna layer, the liquid crystal layer is arranged on the side of the antenna ground layer facing away from the antenna layer, and the phase shift layer is arranged on the side of the liquid crystal layer facing away from the antenna layer. The cell thickness of the liquid crystal layer ranges from 13 microns to 18 microns.

2. The antenna unit according to claim 1, wherein: The phase shift layer includes a plurality of functional components, each of which includes: Slow-wave branch structures, each of the slow-wave branch structures is arranged corresponding to each of the antenna bodies; A bias line is connected to the slow-wave branch structure, and the bias line is used to provide direct current to the slow-wave branch structure.

3. The antenna unit according to claim 2, wherein: Each of the functional components further includes a delay line connected to an end of the slow-wave branch structure away from the bias line.

4. The antenna unit according to claim 3, wherein: The number of the functional parts is four, and the four functional parts are symmetrical in pairs.

5. The antenna unit according to claim 2, wherein: The antenna unit also includes a power divider layer, which is arranged between the antenna layer and the phase shifter. The power divider layer includes an input branch, a first output branch and a second output branch. The first output branch and the second output branch are connected and commonly connected to the input branch.

6. The antenna unit according to claim 5, characterized in that The first output branch and the second output branch have a phase difference of 180°; and / or The thickness of the power divider layer is 12 microns.

7. The antenna unit according to claim 5, characterized in that The antenna ground layer is provided with a first coupling slot, and the power divider layer and the phase shift layer are coupled through the first coupling slot; and / or The antenna stratum is further provided with a plurality of second coupling slots, and each of the antenna bodies is coupled to each of the slow-wave branch structures through each of the second coupling slots.

8. The antenna unit according to claim 7, characterized in that The antenna stratum is further provided with a plurality of third coupling slots, and each of the slow-wave branch structures is coupled to the antenna stratum through each of the third coupling slots.

9. The antenna unit according to any one of claims 1 to 8, characterized in that: The length and width of the antenna unit are 23.3 mm and 21.8 mm, and the thickness of the antenna unit is in the range of 0.9 mm to 1 mm; and / or The gain of the antenna unit is 5dBi.

10. An antenna array, characterized in that: The invention comprises the antenna units according to any one of claims 1 to 9 distributed in an array.

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