Antenna and communication device

Abstract

The present application relates to the technical field of communications. Disclosed are an antenna and a communication device. The antenna comprises a feed network, a plurality of phase shift units and a plurality of reconfigurable antenna subarrays, wherein the feed network comprises an input end and a plurality of output ends; each phase shift unit is connected between one output end of the feed network and one reconfigurable antenna subarray; each phase shift unit is used for adjusting the phase of a radio frequency signal outputted by the feed network and then outputting same to one reconfigurable antenna subarray; each phase shift unit comprises a first transmission line, a second transmission line and a liquid crystal layer, the liquid crystal layer being arranged between the first transmission line and the second transmission line, the physical length of the first transmission line and the physical length of the second transmission line both being L, the guided wavelength for the first transmission line and the guided wavelength for the second transmission line both being λg, and L and λg satisfying L≤1 / 4λg; and each reconfigurable antenna subarray comprises a plurality of 1-bit antenna units. The antenna can reduce the signal transmission loss and the manufacturing cost while improving the performance.

Description

An antenna and communication device

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202410802875.7, filed on June 19, 2024, entitled "An Antenna and Communication Device", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of communication technology, and in particular to an antenna and communication device. Background Technology

[0004] Phase shifters in antennas regulate the phase of electromagnetic waves, controlling the antenna's radiation direction and beam shape. Therefore, the performance of the phase shifter directly determines the antenna's performance, thus affecting the communication performance of the communication terminal. Liquid crystal phase shifters (LCDs) are a common type of dielectric phase shifter. They utilize the change in the dielectric constant of liquid crystals under an electric field to alter the signal propagation speed and phase delay, thereby achieving phase modulation. Traditional LCD phase shifters have a transmission line physical length of at least 0.5 times the waveguide wavelength, resulting in high transmission loss and a complex structure, which hinders cost reduction. Summary of the Invention

[0005] This application provides an antenna and a communication device that reduces antenna transmission loss and manufacturing cost while improving antenna performance.

[0006] In a first aspect, this application provides an antenna comprising a feed network, multiple phase-shifting units, and multiple reconfigurable antenna subarrays. The feed network includes an input terminal and multiple output terminals, allowing the feed network to feed radio frequency (RF) signals input from its input terminal to each of the output terminals. The multiple phase-shifting units are configured one-to-one with the multiple output terminals of the feed network, and also one-to-one with the multiple reconfigurable antenna subarrays. Each phase-shifting unit is connected between one output terminal of the feed network and one reconfigurable antenna subarray, and is used to adjust the phase of the RF signal output from the feed network before outputting it to the reconfigurable antenna subarray. The reconfigurable antenna subarray includes multiple 1-bit antenna elements, which radiate RF signals into free space. Each phase-shifting unit includes a first transmission line, a second transmission line, and a liquid crystal layer. The liquid crystal layer is disposed between the first and second transmission lines. The first and second transmission lines can adjust the dielectric constant of the liquid crystal layer by applying a voltage, thereby changing their phase constants and thus adjusting the phase of the transmitted signal. In this application, the physical lengths of the first and second transmission lines are L, and the guided wavelengths of the first and second transmission lines are λg. L and λg satisfy: L ≤ 1 / 4λg. Compared to the physical length of more than 1 / 2λg required for the transmission lines of traditional liquid crystal phase-shifting units, the physical length of the transmission lines in the phase-shifting unit provided in this application is significantly shortened, thereby reducing signal transmission loss in the phase-shifting unit and lowering its cost. Furthermore, based on the positive correlation between the physical length of the transmission line and the phase-shifting range of the phase-shifting unit, the phase-shifting range of the phase-shifting unit in this application can reach 90°. Within this phase-shifting range, the phase-shifting unit can reduce the phase quantization error of a 1-bit antenna element, thereby reducing antenna sidelobes and improving antenna beam gain and pointing accuracy.

[0007] In some implementations, the antenna also includes a phase-shift control module, which is connected to each phase-shifting unit to regulate the operating state of each phase-shifting unit.

[0008] In some implementations, the antenna also includes a beam control module connected to the antenna elements in each reconfigurable antenna subarray for controlling the operating state of the antenna elements.

[0009] In some embodiments, the phase-shifting unit includes a first substrate and a second substrate. A receiving groove is formed on one side surface of the first substrate, and the second substrate covers the side surface of the first substrate with the receiving groove to seal it. A liquid crystal layer is filled within the receiving groove to maintain the structural and positional stability of the liquid crystal layer. A first transmission line may be disposed on the first substrate to facilitate its fabrication and reliable positioning. Similarly, a second transmission line may be disposed on the second substrate to facilitate its fabrication and reliable positioning.

[0010] In some embodiments, the first transmission line may be disposed at the bottom of the receiving groove, that is, the first transmission line is disposed inside the receiving groove, and the first transmission line is in direct contact with the liquid crystal layer, thereby enabling reliable voltage application to the liquid crystal layer. In other embodiments, the first transmission line may be disposed on the surface of the first substrate facing away from the second substrate, that is, the first transmission line is disposed outside the receiving groove, and the first transmission line and the liquid crystal layer are separated by the first substrate. This design facilitates the connection of the first transmission line to the feed network and the reconfigurable antenna subarray.

[0011] In some embodiments, the second transmission line is disposed on the surface of the second substrate facing the first substrate, that is, the second transmission line is disposed within a receiving groove and is in direct contact with the liquid crystal layer, thereby enabling reliable voltage application to the liquid crystal layer. In other embodiments, the second transmission line may be disposed on the surface of the second substrate away from the first substrate, that is, the second transmission line is disposed outside the receiving groove, and the second transmission line is spaced from the liquid crystal layer by the second substrate. This design facilitates the connection of the second transmission line to the feed network and the reconfigurable antenna subarray.

[0012] In some implementations, the first transmission line can be a ground plane, or it can be a microstrip line. Microstrip lines are small in size and have low manufacturing costs, which helps to achieve miniaturization of the phase-shifting unit and reduce its cost.

[0013] In some implementations, the first and second transmission lines are parallel twin lines. Parallel twin lines also have the advantage of low cost and relatively light weight, thus reducing the cost of the phase shifting unit and the overall weight.

[0014] In some embodiments, when the first transmission line is disposed at the bottom of the receiving groove and the second transmission line is disposed on the side surface of the second substrate facing the first substrate, one or more first protrusions may be provided on the side of the first transmission line facing the second transmission line, and one or more second protrusions may be provided on the side of the second transmission line facing the first transmission line. By providing protrusion structures on the first and second transmission lines, the phase constants of the first and second transmission lines can be adjusted, thereby controlling the phase shifting range of the phase shifting unit.

[0015] In some embodiments, the phase-shifting unit further includes a phase-shifting bias circuit, which may be disposed on the surface of the second substrate facing away from the first substrate, and the phase-shifting bias circuit is connected to the second transmission line. The positive terminal of the phase-shifting control module is connected to the second transmission line through the phase-shifting bias circuit, and the negative terminal of the phase-shifting control module is connected to the first transmission line, thereby controlling the voltage between the first transmission line and the second transmission line.

[0016] In some implementations, the antenna element includes a first radiator, a second radiator, and an electronic control element connected between the first and second radiators. By adjusting the switching state of the electronic control element, the first and second radiators can be connected or disconnected, thereby enabling the antenna element to achieve two different operating states, thus forming a 1-bit antenna element.

[0017] In some implementations, the reconfigurable antenna subarray includes a subarray feed network, which includes a sub-input terminal and multiple sub-output terminals. The sub-input terminal of the subarray feed network can be connected to a phase-shifting unit, and the multiple sub-output terminals of the subarray feed network are respectively connected to multiple antenna elements to feed the radio frequency signal input from the phase-shifting unit from the sub-input terminal to the multiple antenna elements respectively.

[0018] In some embodiments, the subarray feed network includes a first sub-dielectric substrate, a first sub-metal layer, and a second sub-metal layer, which are respectively disposed on two opposite surfaces of the first sub-dielectric substrate. The first sub-dielectric substrate has a first column of vias and a second column of vias, which are opposite to and spaced apart. Each column of vias includes multiple metal vias spaced apart along a first direction. One end of each metal via is electrically connected to the first sub-metal layer, and the other end of each metal via is electrically connected to the second sub-metal layer. The first column of vias, the second column of vias, the first sub-metal layer, and the second sub-metal layer can be enclosed to form a waveguide cavity, which can connect a phase-shifting unit and an antenna unit, thereby feeding the radio frequency signal input from the phase-shifting unit into the antenna unit.

[0019] In some embodiments, the reconfigurable antenna subarray includes a second sub-dielectric substrate disposed on the side of the first sub-metal layer opposite to the first sub-dielectric substrate. A plurality of antenna elements are disposed on the second sub-dielectric substrate along a first direction, and the orthographic projection of the plurality of antenna elements onto the second sub-dielectric substrate lies within the orthographic projection of the waveguide cavity onto the surface of the second sub-dielectric substrate. The second sub-metal layer is provided with a plurality of slots spaced apart along the first direction, each slot being positioned opposite to one of the plurality of antenna elements, and each slot being used to couple a signal within the waveguide cavity to a corresponding antenna element.

[0020] In some implementations, a feed transmission line is formed between the input and each output of the feed network. Among multiple feed transmission lines, at least two have different physical lengths. In this case, the phase delay of the radio frequency signals transmitted in the feed transmission lines with different physical lengths will also be different, thus achieving the effect of non-uniform phase feeding. Non-uniform phase feeding can, to a certain extent, disrupt the periodicity of each antenna element, thereby suppressing grating lobes and helping to improve the antenna's radiation performance.

[0021] In some embodiments, the feed network includes a dielectric substrate, a first metal layer, and a second metal layer, which are respectively disposed on two opposite surfaces of the dielectric substrate. The dielectric substrate has multiple metal vias, one end of which is electrically connected to the first metal layer, and the other end of which is electrically connected to the second metal layer. A first portion of the metal vias is arranged to form a horn-shaped structure, which, together with the first and second metal layers, can enclose a horn-shaped waveguide cavity. A second portion of the metal vias is arranged in multiple rows, which are positioned at the flared end of the horn-shaped waveguide cavity. Each pair of adjacent rows of metal vias, together with the first and second metal layers, can enclose a linear waveguide cavity. One end of each linear waveguide cavity is connected to the flared end of the horn-shaped waveguide cavity. In this way, a feed transmission line can be formed between the narrow end of the horn-shaped waveguide cavity and the other end of each linear waveguide cavity. The narrow end of the horn-shaped waveguide cavity serves as the input end of the feed network, and the other end of each linear waveguide cavity serves as the output end of the feed network.

[0022] Secondly, this application also provides a communication device, which includes a radio frequency (RF) device and an antenna as described in any of the embodiments of the first aspect, wherein the RF device is connected to the antenna. Specifically, the RF device can be connected to the input of a feed network to feed RF signals into the feed network, which then feeds the signals to the reconfigurable antenna subarray via a phase-shifting unit.

[0023] In some implementations, the communication equipment can be a base station. In this case, the radio frequency device is a radio frequency processing unit, which can be used to select, amplify, and convert the electromagnetic wave signal received by the antenna into a baseband signal. Alternatively, the radio frequency processing unit can be used to up-convert and amplify the baseband signal and then convert it into an electromagnetic wave through the antenna for transmission.

[0024] In some implementations, the communication device can be a terminal. In this case, the radio frequency device is a radio frequency chip, which can be used to select, amplify, and convert the electromagnetic wave signal received by the antenna into a baseband signal. Alternatively, the radio frequency chip can be used to up-convert and amplify the baseband signal and then convert it into an electromagnetic wave for transmission through the antenna. Attached Figure Description

[0025] Figure 1 is a communication system architecture diagram provided in an embodiment of this application;

[0026] Figure 2 is a partial structural diagram of a base station provided in an embodiment of this application;

[0027] Figure 3 is an architecture diagram of an antenna provided in an embodiment of this application;

[0028] Figure 4 is a schematic diagram of a planar structure of the antenna shown in Figure 3;

[0029] Figure 5 is a side cross-sectional view of a power supply network provided in an embodiment of this application;

[0030] Figure 6 is a top view of the power supply network shown in Figure 5;

[0031] Figure 7 is a side sectional view of a phase shifting unit provided in an embodiment of this application;

[0032] Figure 8 is a top view of the phase-shifting unit shown in Figure 7;

[0033] Figure 9 is a side sectional view of another phase-shifting unit provided in an embodiment of this application;

[0034] Figure 10 is a side cross-sectional view of another phase-shifting unit provided in an embodiment of this application;

[0035] Figure 11 is an architecture diagram of a reconfigurable antenna subarray provided in an embodiment of this application;

[0036] Figure 12 is an architectural diagram of another reconfigurable antenna subarray provided in an embodiment of this application;

[0037] Figure 13 is a partial side cross-sectional view of a reconfigurable antenna subarray provided in an embodiment of this application;

[0038] Figure 14 is a top view of the reconfigurable antenna subarray shown in Figure 13;

[0039] Figure 15 is another top view of the reconfigurable antenna subarray shown in Figure 13;

[0040] Figure 16 is a top view of an antenna provided in an embodiment of this application.

[0041] Reference numerals: 1000-Base station; 100-Antenna; 110-Feed network; 111-Input terminal; 112-Output terminal; 113-Feed transmission line; 114-Dielectric substrate; 1141 / 1252 / 1261 / 13231-Metal vias; 1141a-First part of metal vias; 1141b-Second part of metal vias; 115-First metal layer; 116-Second metal layer; 117-Horn-shaped waveguide cavity; 1171-Narrow end; 1172-Wave end; 118-Linear waveguide cavity; 120-Phase shifting unit; 121-First transmission line; 1211-First protrusion; 122-Second transmission line; 1221-Second protrusion; 1222-Waveguide microstrip conversion structure; 123-Liquid crystal layer; 124-Phase shifting bias circuit; 125-First substrate; 1251-Receiving slot; 1253-First slot; 1262-Second slot; 126-Second substrate; 130-Reconfigurable antenna subarray; 131-Antenna element; 1311-First radiator; 1312-Second radiator; 1313-Electrical control element; 132-Subarray feed network; 1321-Sub-input terminal; 1322-Sub-output terminal; 1323-First sub-dielectric substrate; 1324-First sub-metal layer; 1325-Second sub-metal layer; 13251-Gap; 13231a-First column via; 13231b-Second column via; 1326-Second sub-dielectric substrate; 1327-Waveguide cavity; 1328-Feed bias circuit; 1329-Isolation hole; 140-Phase shift control module; 150-Beam control module; 200-Mount; 300 - Radio frequency processing unit; 400 - Baseband processing unit. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings. However, the exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein. The same reference numerals in the figures denote the same or similar structures, and therefore repeated descriptions of them will be omitted. The terms expressing position and direction described in the embodiments of this application are illustrative based on the accompanying drawings, but changes can be made as needed, and all such changes are included within the scope of protection of this application. The accompanying drawings of the embodiments of this application are only for illustrating relative positional relationships and do not represent actual scale.

[0043] It should be noted that specific details are set forth in the following description to facilitate understanding of this application. However, the embodiments of this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the embodiments of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0044] The antenna provided in this application embodiment is used in various communication devices, such as base stations, customer premise equipment (CPE), terminals, and other devices with communication functions. Specifically, the communication device can be a device employing one or more of the following communication technologies: Bluetooth (BT) communication technology, Global Positioning System (GPS) communication technology, Wireless Fidelity (WiFi) communication technology, Global System for Mobile Communications (GSM) communication technology, Wideband Code Division Multiple Access (WCDMA) communication technology, Long Term Evolution (LTE) communication technology, 5G communication technology, and future communication technologies, etc.

[0045] Figure 1 shows a communication system architecture diagram consisting of a base station and a terminal. Both the base station and the terminal include antennas, and they can communicate wirelessly through their respective antennas. For example, the terminal can communicate directly with the base station or through a relay station. Furthermore, the terminal can communicate with multiple base stations using different communication technologies.

[0046] In one implementation, the communication device provided in this application embodiment is a base station. Referring to FIG2, FIG2 is a partial structural schematic diagram of a base station. In addition to the antenna 100, the base station 1000 also includes a support pole 200, a radio frequency processing unit 300, and a baseband processing unit 400. The antenna 100 can be mounted on the support pole 200 via a bracket to facilitate receiving or transmitting electromagnetic waves. The radio frequency processing unit 300 is connected to the antenna 100, and the baseband processing unit 400 is connected to the radio frequency processing unit 300. The radio frequency processing unit 300 can be used to perform frequency selection, amplification, and frequency conversion processing on the electromagnetic wave signal received by the antenna 100, and convert it into a baseband signal and send it to the baseband processing unit 400. Alternatively, the radio frequency processing unit 300 can be used to up-convert and amplify the baseband signal of the baseband processing unit 400, and then convert it into an electromagnetic wave through the antenna 100 for transmission. The baseband processing unit 400 is used to process and modulate the baseband signal. In some embodiments, the radio frequency processing unit 300 may also be referred to as a remote radio unit (RRU), and the baseband processing unit 400 may also be referred to as a baseband unit (BBU).

[0047] The radio frequency (RF) processing unit 300 and the baseband processing unit 400 can be connected via a connecting wire. In one possible embodiment, the RF processing unit 300 and the baseband processing unit 400 can be located at the far end of the antenna. In another possible embodiment, the RF processing unit 300 can be integrated with the antenna 100, and the baseband processing unit 400 can be located at the far end of the antenna. In this example, the RF processing unit 300 and the antenna 100 can be collectively referred to as an active antenna unit (AAU).

[0048] In one implementation, the communication device provided in this application embodiment is a terminal. Besides the antenna, the terminal also includes a radio frequency (RF) chip and a baseband chip. The RF chip is connected to the antenna, and the baseband chip is connected to the RF chip. The RF chip can be used to perform frequency selection, amplification, and frequency conversion processing on the electromagnetic wave signal received by the antenna, and convert it into a baseband signal for transmission to the baseband chip. Alternatively, the RF chip can be used to up-convert and amplify the baseband signal from the baseband chip, convert it into an electromagnetic wave, and transmit it through the antenna. The baseband chip is used to process and modulate / demodulate the baseband signal.

[0049] In this embodiment, the terminal may include a fixed terminal and a mobile terminal. The mobile terminal may be a mobile phone, tablet computer, laptop computer, smart bracelet, smartwatch, smart helmet, or smart glasses, etc.; the fixed terminal may be a vehicle-mounted terminal, router, smart TV, smart home device, smart speaker, or desktop computer, etc. Furthermore, the aforementioned terminals may also be handheld devices with wireless communication capabilities, computing devices, other processing devices connected to a wireless modem, vehicle-mounted devices, communication terminals in 5G networks, or communication terminals in future evolved public land mobile networks (PLMNs), etc., and this application embodiment does not limit these possibilities.

[0050] Furthermore, when the communication device is used as a terminal, it can also be used in satellite communication to communicate with communication satellites. Satellite communication belongs to non-terrestrial network (NTN) communication, and compared to terrestrial communication, satellite communication can provide a wider coverage area. Especially for areas with few or no cellular communication base stations, satellite communication can effectively improve the communication capabilities of the terminal.

[0051] In some embodiments, the antenna can be a circuit board antenna based on the terminal circuit board, a frame antenna based on the metal frame of the terminal housing, or an antenna based on a flexible printed circuit (FPC), an antenna based on laser-direct-structuring (LDS) technology, or a microstrip disk antenna (MDA), etc. Of course, in some embodiments, the terminal can also use a combination of multiple antenna types mentioned above.

[0052] The above only lists a few possible forms of communication equipment. It should be understood that the antenna provided in the embodiments of this application can also be applied to other devices with communication functions, and the specifics will not be elaborated here.

[0053] Figure 3 is an architectural diagram of an antenna 100 provided in an embodiment of this application, and Figure 4 is a planar structural schematic diagram of the antenna 100 shown in Figure 3. Referring to Figures 2 and 3 together, in this embodiment of the application, the antenna 100 includes a feed network 110, a plurality of phase-shifting units 120, and a plurality of reconfigurable antenna subarrays 130. The feed network 110 includes an input terminal 111 and a plurality of output terminals 112. The input terminal 111 of the feed network 110 can be connected to the radio frequency device of a communication device, and the feed network 110 can feed the radio frequency signal fed from the input terminal 111 by the radio frequency device to the plurality of output terminals 112 respectively. Exemplarily, when the communication device is a base station, the radio frequency device is the radio frequency processing unit of the base station; when the communication device is a terminal, the radio frequency device is the radio frequency chip of the terminal. Multiple phase-shifting units 120 are configured one-to-one with multiple output terminals 112 of the feed network 110, and multiple phase-shifting units 120 are configured one-to-one with multiple reconfigurable antenna subarrays 130. Each phase-shifting unit 120 is connected between one output terminal 112 of the feed network 110 and one reconfigurable antenna subarray 130. The phase-shifting unit 120 is used to adjust the phase of the radio frequency signal output from the feed network 110 and then output it to the reconfigurable antenna subarray 130. The reconfigurable antenna subarray 130 includes multiple 1-bit antenna elements 131, which are used to radiate radio frequency signals into free space.

[0054] In some embodiments, the antenna 100 further includes a phase shift control module 140, which is connected to each phase shift unit 120 to regulate the operating state of each phase shift unit 120. In some embodiments, the antenna 100 further includes a beam control module 150, which is connected to the antenna elements 131 in each reconfigurable antenna subarray 130 to control the operating state of the antenna elements 131.

[0055] In this embodiment, a feed transmission line 113 is formed between the input terminal 111 and each output terminal 112 of the feed network 110, and each feed transmission line 113 outputs a radio frequency signal to a corresponding phase shifting unit 120. In one implementation, at least two of the multiple feed transmission lines 113 have different physical lengths. In this case, the phase delay of the radio frequency signal transmitted in the feed transmission lines 113 with different physical lengths will also be different, thereby achieving the effect of non-uniform phase feeding. In other words, the feed network 110 in this embodiment can be a non-uniform feed network. The non-uniform feed network can, to a certain extent, disrupt the periodicity of each antenna element 131, thereby achieving the effect of suppressing grating lobes and helping to improve the radiation performance of the antenna 100.

[0056] Of course, in another implementation, multiple power supply transmission lines 113 can also have the same physical length. In this case, the power supply network 110 is an equal-phase power supply network.

[0057] Figure 5 is a side cross-sectional view of a feed network 110 provided in an embodiment of this application, and Figure 6 is a top view of the feed network 110 shown in Figure 5. Referring to Figures 5 and 6 together, in this embodiment of the application, the feed network 110 can adopt a substrate integrated waveguide structure. The feed network 110 includes a dielectric substrate 114, a first metal layer 115, and a second metal layer 116. The first metal layer 115 and the second metal layer 116 are respectively disposed on two opposite surfaces of the dielectric substrate 114. The dielectric substrate 114 is provided with a plurality of metal vias 1141. The plurality of metal vias 1141 penetrate the dielectric substrate 114 along the thickness direction of the dielectric substrate 114, and one end of each metal via 1141 is electrically connected to the first metal layer 115, and the other end of each metal via 1141 is electrically connected to the second metal layer 116. The dielectric substrate 114 can be made of a material with low dielectric loss and high dielectric constant, such as ceramic, quartz, or polymer; the first metal layer 115 and the second metal layer 116 can be made of highly conductive materials such as copper or aluminum. For example, one of the first metal layer 115 and the second metal layer 116 can be a ground plane.

[0058] Of the multiple metal vias 1141, the first portion of metal vias 1141a is arranged to form a horn-shaped structure, which, together with the first metal layer 115 and the second metal layer 116, can enclose a horn-shaped waveguide cavity 117. This horn-shaped waveguide cavity 117 includes a narrow end 1171 and a flared end 1172, with the diameter of the narrow end 1171 being smaller than the diameter of the flared end 1172. Of the multiple metal vias 1141, the second portion of metal vias 1141b is arranged in multiple rows, with these rows of metal vias 1141 positioned at the flared end 1172 of the horn-shaped waveguide cavity 117. Each pair of adjacent rows of metal vias 1141, together with the first metal layer 115 and the second metal layer 116, can enclose a linear waveguide cavity 118. For example, in the embodiments shown in Figures 5 and 6, the second portion of vias 1141b is arranged in five columns, and the five columns of metal vias 1141, together with the first metal layer 115 and the second metal layer 116, form four linear waveguide cavities 118.

[0059] In this configuration, one end of each linear waveguide cavity 118 is connected to the flared end 1172 of the horn-shaped waveguide cavity 117. Thus, a feed transmission line 113 is formed between the narrow end 1171 of the horn-shaped waveguide cavity 117 and the other end of each linear waveguide cavity 118. The narrow end 1171 of the horn-shaped waveguide cavity 117 serves as the input end of the feed network 110, and the other end of each linear waveguide cavity 118 serves as the output end of the feed network 110. As can be seen from the figure, due to the horn-shaped structural characteristics, at least two feed transmission lines 113 have different physical lengths. Therefore, the feed network 110 can achieve non-uniform phase feeding, thereby suppressing grating lobes.

[0060] Figure 7 is a side sectional view of a phase-shifting unit 120 provided in an embodiment of this application, and Figure 8 is a top view of the phase-shifting unit 120 shown in Figure 7. Referring to Figures 7 and 8 together, in this embodiment of the application, the phase-shifting unit 120 can be in the form of a liquid crystal phase-shifting unit. The phase-shifting unit 120 includes a first transmission line 121, a second transmission line 122, and a liquid crystal layer 123, with the liquid crystal layer 123 disposed between the first transmission line 121 and the second transmission line 122. The first transmission line 121 and the second transmission line 122 connect the output end of the feed network and the reconfigurable antenna subarray. The first transmission line 121 and the second transmission line 122 are used both to transmit signals and to apply voltage to the liquid crystal layer 123 to change the orientation distribution of the liquid crystal layer 123, thereby controlling the dielectric constant of the liquid crystal layer 123. This, in turn, changes the phase constant of the first transmission line 121 and the second transmission line 122, achieving phase adjustment of the transmitted signal and ultimately achieving phase modulation. In addition, the phase shifting unit 120 also includes a phase shifting bias circuit 124. The phase shifting control module 140 is connected to at least one of the first transmission line 121 and the second transmission line 122 through the phase shifting bias circuit 124 to control the voltage between the first transmission line 121 and the second transmission line 122 through the phase shifting bias circuit 124.

[0061] For the phase-shifting unit 120, the phase-shifting range φ of the phase-shifting unit 120 satisfies the relationship between the physical length L of the first transmission line 121 and the second transmission line 122 and the phase constant β: φ = βL. It can be seen that the physical length L of the first transmission line 121 and the second transmission line 122 is positively correlated with the phase-shifting range φ of the phase-shifting unit 120. Traditional liquid crystal phase-shifting units 120 are often used in conjunction with high-bit antenna units to achieve beam scanning functionality. The phase-shifting range of the phase-shifting unit must be at least 180°, and correspondingly, the physical length of the transmission line must be at least 1 / 2λg (λg is the guided wavelength of the transmission line). Excessive physical length of the transmission line leads to higher transmission loss and increases material costs.

[0062] In this embodiment, since the antenna elements of the reconfigurable antenna subarray are 1-bit antenna elements, the phase shifting unit 120 that works with it is mainly used to optimize phase quantization error rather than precisely control beam pointing. Therefore, the phase shifting range requirement for the phase shifting unit 120 is relatively small. Based on this, the phase shifting range of the phase shifting unit 120 in this embodiment can be designed to be greater than or equal to 90°. This can reduce the phase quantization error of the antenna, thereby reducing antenna sidelobes and improving antenna beam gain and pointing accuracy.

[0063] Based on the correspondence between the phase shift range of the phase shift unit 120 and the physical lengths of the first transmission line 121 and the second transmission line 122, when the phase shift range of the phase shift unit 120 is greater than or equal to 90°, the length L of the first transmission line 121 and the second transmission line 122 satisfies the following relationship with the guided wavelength λg of the first transmission line 121 and the second transmission line 122: L ≤ 1 / 4λg. Therefore, compared with traditional liquid crystal phase shift units, the physical lengths of the first transmission line 121 and the second transmission line 122 of the phase shift unit 120 in this embodiment are significantly shortened. This allows the antenna using the phase shift unit 120 to achieve improved performance while also reducing signal transmission loss in the phase shift unit 120 and lowering the cost of the phase shift unit 120.

[0064] Please continue referring to Figure 7. In this embodiment, the phase-shifting unit 120 further includes a first substrate 125 and a second substrate 126. A receiving groove 1251 is provided on one side surface of the first substrate 125. The second substrate 126 covers the side surface of the first substrate 125 where the receiving groove 1251 is provided, thereby sealing the receiving groove 1251. The liquid crystal layer 123 is filled in the receiving groove, so that the receiving groove 1251 is used to maintain the structural and positional stability of the liquid crystal layer 123. Therefore, the structure composed of the first substrate 125 and the second substrate 126 can also be called a liquid crystal cell. The materials of the first substrate 125 and the second substrate 126 can be glass, quartz, ceramic, etc.

[0065] In this embodiment, the first transmission line 121 is disposed on the first substrate 125 to facilitate its fabrication and reliable positioning. Similarly, the second transmission line 122 is disposed on the second substrate 126 to facilitate its fabrication and reliable positioning. The specific types of the first transmission line 121 and the second transmission line 122 are not limited. For example, in the embodiment shown in FIG. 7, the first transmission line 121 is a ground plane, and the second transmission line 122 is a microstrip line. In other embodiments, the first transmission line 121 and the second transmission line 122 may also be parallel bilinear lines.

[0066] In some embodiments, the first transmission line 121 is disposed on the surface of the first substrate 125 facing away from the second substrate 126, and the second transmission line 122 is disposed on the surface of the second substrate 126 facing away from the first substrate 125. That is, the first transmission line 121 and the second transmission line 122 are respectively located outside the receiving groove 1251, with the first transmission line 121 and the liquid crystal layer 123 separated by the first substrate 125, and the second transmission line 122 and the liquid crystal layer 123 separated by the second substrate 126. In this case, the phase-shifting bias circuit 124 can be disposed on the surface of the second substrate 126 facing away from the first substrate 125, and the phase-shifting bias circuit 124 is connected to the second transmission line 122. The positive terminal of the phase-shifting control module 140 is connected to the second transmission line 122 through the phase-shifting bias circuit 124, and the negative terminal of the phase-shifting control module 140 is connected to the first transmission line 121, thereby controlling the voltage between the first transmission line 121 and the second transmission line 122. For example, the first substrate 125 and the second substrate 126 are respectively provided with metal vias. The metal via 1252 of the first substrate 125 is disposed in the area that avoids the receiving groove 1251. The metal via 1261 of the second substrate 126 is positioned opposite to the metal via 1252 of the first substrate 125. The phase shift control module 140 is connected to the phase shift bias circuit 124 in sequence through the metal via 1252 of the first substrate 125 and the metal via 1261 of the second substrate 126.

[0067] Figure 9 is a side cross-sectional view of another phase-shifting unit 120 provided in an embodiment of this application. Referring to Figure 9, in this embodiment, the first transmission line 121 is disposed at the bottom of the receiving groove 1251, and the second transmission line 122 is disposed on the side surface of the second substrate 126 facing the first substrate 125. That is, the first transmission line 121 and the second transmission line 122 are respectively located in the receiving groove 1251, the first transmission line 121 is in direct contact with the liquid crystal layer 123, and the second transmission line 122 is in direct contact with the liquid crystal layer 123. In this case, the phase-shifting bias circuit 124 can be disposed on the side surface of the first substrate 125 facing away from the second substrate 126, or it can be disposed on the side surface of the second substrate 126 facing away from the first substrate 125, as shown in Figure 9 as an example of the phase-shifting bias circuit 124 being disposed on the second substrate 126. In this example, the first substrate 125 is provided with a first groove 1253, and the second substrate 126 is provided with a second groove 1262. The first groove 1253 and the second groove 1262 can respectively connect the receiving groove 1251 to the outside. The positive terminal of the phase shift control module 140 is connected to the phase shift bias circuit 124. The phase shift bias circuit 124 is connected to the second transmission line 122 through the second groove 1262. The negative terminal of the phase shift control module 140 is connected to the first transmission line 121 through the first groove 1253. Similarly, the first substrate 125 and the second substrate 126 are respectively provided with metal vias. The metal via 1252 of the first substrate 125 is located in the area that avoids the receiving groove 1251. The metal via 1261 of the second substrate 126 is positioned opposite to the metal via 1252 of the first substrate 125. The phase shift control module 140 is connected to the phase shift bias circuit 124 in sequence through the metal via 1252 of the first substrate 125 and the metal via 1261 of the second substrate 126.

[0068] It should be understood that in some other embodiments, the first transmission line 121 and the second transmission line 122 may also be located, one inside the receiving groove 1251 and the other outside the receiving groove 1251. For example, the first transmission line 121 may be disposed on the side surface of the first substrate 125 facing away from the second substrate 126, and the second transmission line 122 may be disposed on the side surface of the second substrate 126 facing the first substrate 125; or, the first transmission line 121 may be disposed at the bottom of the receiving groove 1251, and the second transmission line 122 may be disposed on the side surface of the second substrate 126 facing away from the first substrate 125.

[0069] Figure 10 is a side cross-sectional view of another phase-shifting unit 120 provided in an embodiment of this application. Figure 10 shows an example where the first transmission line 121 and the second transmission line 122 are parallel double lines. Referring to Figure 10, in this embodiment, one or more first protrusions 1211 are provided on the side of the first transmission line 121 facing the second transmission line 122, and the one or more first protrusions 1211 are arranged along the length direction of the first transmission line 121. One or more second protrusions 1221 are provided on the side of the second transmission line 122 facing the first transmission line 121, and the one or more second protrusions 1221 are arranged along the length direction of the second transmission line 122. By providing protrusion structures on the first transmission line 121 and the second transmission line 122, the phase constants of the first transmission line 121 and the second transmission line 122 can be adjusted, thereby controlling the phase-shifting range of the phase-shifting unit 120.

[0070] For example, when the number of protrusions in a transmission line is more than three, left-handed or right-handed metamaterial transmission lines can be constructed (left-handed materials are those where the directions of the electric field strength, magnetic field strength, and wave vector follow the left-hand rule, and right-handed materials are those where the directions of the electric field strength, magnetic field strength, and wave vector follow the right-hand rule), thereby increasing the equivalent capacitance of the transmission line, while the phase constant of the transmission line... Where f is the resonant frequency, L is the inductance of the equivalent circuit model, and C is the equivalent capacitance. Therefore, increasing the equivalent capacitance can increase the phase constant, and thus increase the phase shifting range of the phase shifting unit 120.

[0071] In one implementation, the plurality of first protrusions 1211 of the first transmission line 121 are periodically distributed along the length direction of the first transmission line 121, that is, the size and spacing of two adjacent first protrusions 1211 are the same, so as to reduce the manufacturing difficulty of the first transmission line 121. Similarly, the plurality of second protrusions 1221 of the second transmission line 122 can also be periodically distributed along the length direction of the second transmission line 122.

[0072] In another implementation, the plurality of first protrusions 1211 of the first transmission line 121 are distributed aperiodically along the length of the first transmission line 121, that is, the size and / or spacing of two adjacent first protrusions 1211 are inconsistent; similarly, the plurality of second protrusions 1221 of the second transmission line 122 are distributed aperiodically along the length of the second transmission line 122, that is, the size and / or spacing of two adjacent second protrusions 1221 are inconsistent. This design increases the design freedom of the phase shifting unit 120, helping to achieve a larger phase shifting range and lower transmission loss.

[0073] Figure 11 is an architectural diagram of a reconfigurable antenna subarray 130 provided in an embodiment of this application. Referring to Figure 11, in this embodiment, the reconfigurable antenna subarray 130 further includes a subarray feed network 132. The subarray feed network 132 includes a sub-input terminal 1321 and multiple sub-output terminals 1322. The sub-input terminal 1321 of the subarray feed network 132 can be connected to a phase-shifting unit, and the multiple sub-output terminals 1322 of the subarray feed network 132 are respectively connected to multiple antenna elements 131 to feed the radio frequency signal input from the phase-shifting unit from the sub-input terminal 1321 to the multiple antenna elements 131 respectively. As shown in Figure 11, in this embodiment, the multiple sub-output terminals 1322 of the subarray feed network 132 are connected in series, so the multiple antenna elements 131 of the reconfigurable antenna subarray 130 can be connected in series. The beam control module 150 is connected to each antenna element 131 to control the working state of each antenna element 131.

[0074] Figure 12 is an architectural diagram of another reconfigurable antenna subarray 130 provided in an embodiment of this application. Referring to Figure 12, in this embodiment, the multiple sub-output terminals 1322 of the subarray feed network 132 are connected in parallel with each other. Therefore, the multiple antenna elements 131 of the reconfigurable antenna subarray 130 can be connected in parallel. Similarly, the beam control module 150 is connected to each antenna element 131 to control the operating state of each antenna element 131.

[0075] Figure 13 is a partial side cross-sectional view of a reconfigurable antenna subarray 130 provided in an embodiment of this application. Referring to the figure, in this embodiment, the subarray feed network 132 can also adopt a substrate integrated waveguide structure. The subarray feed network 132 includes a first sub-dielectric substrate 1323, a first sub-metal layer 1324, and a second sub-metal layer 1325. The first sub-metal layer 1324 and the second sub-metal layer 1325 are respectively disposed on two opposite surfaces of the first sub-dielectric substrate 1323. Figure 14 shows a plan view of the reconfigurable antenna subarray on the layer containing the second sub-metal layer 1325. Referring to Figures 13 and 14, the first sub-dielectric substrate 1323 is provided with a first column of vias 13231a and a second column of vias 13231b. The first column of vias 13231a and the second column of vias 13231b are arranged opposite to each other and spaced apart. The first column of vias 13231a and the second column of vias 13231b each include a plurality of metal vias 13231 spaced apart along a first direction, which is the extension direction of the first column of vias 13231a and the second column of vias 13231b. One end of each metal via 13231 is electrically connected to the first sub-metal layer 1324, and the other end of each metal via 13231 is electrically connected to the second sub-metal layer 1325. The first sub-dielectric substrate 1323 can be made of a material with low dielectric loss and high dielectric constant, such as ceramic, quartz, or polymer; the first sub-metal layer 1324 and the second sub-metal layer 1325 can be made of highly conductive materials such as copper or aluminum. For example, one of the first sub-metal layer 1324 and the second sub-metal layer 1325 can be a ground plane.

[0076] In this embodiment, the first column of vias 13231a, the second column of vias 13231b, the first sub-metal layer 1324, and the second sub-metal layer 1325 can be enclosed to form a waveguide cavity 1327. The waveguide cavity 1327 can connect the phase shifting unit and the antenna unit 131, thereby feeding the radio frequency signal input by the phase shifting unit into the antenna unit 131.

[0077] Referring again to Figures 13 and 14, in some embodiments, the reconfigurable antenna subarray 130 includes a second sub-dielectric substrate 1326, which is disposed on the side of the first sub-metal layer 1324 opposite to the first sub-dielectric substrate 1323. A plurality of antenna elements 131 are disposed on the second sub-dielectric substrate 1326 along a first direction, and the orthographic projection of the plurality of antenna elements 131 onto the second sub-dielectric substrate 1326 lies within the orthographic projection of the waveguide cavity 1327 onto the surface of the second sub-dielectric substrate 1326. The second sub-metal layer 1325 is provided with a plurality of slots 13251 spaced apart along the first direction. The plurality of slots 13251 are respectively positioned opposite to the plurality of antenna elements 131, and each slot 13251 can be used to couple a signal within the waveguide cavity 1327 to the corresponding antenna element. It can be seen that in the embodiments shown in Figures 13 and 14, the plurality of antenna elements 131 of the reconfigurable antenna subarray 130 are connected in series.

[0078] Figure 15 is a top view of the reconfigurable antenna subarray 130 shown in Figure 13. Referring to Figures 13 to 15 together, in this embodiment, the antenna element 131 includes a first radiator 1311, a second radiator 1312, and an electronic control element 1313, which is connected between the first radiator 1311 and the second radiator 1312. The electronic control element 1313 can be a diode, a field-effect transistor, or other switching transistor. By adjusting the switching state of the electronic control element 1313, the first radiator 1311 and the second radiator 1312 can be connected or disconnected, thereby enabling the antenna element 131 to achieve two different operating states, thus forming a 1-bit antenna element 131.

[0079] In some embodiments, the first radiator 1311 and the second radiator 1312 are respectively in patch form, and the first radiator 1311 and the second radiator 1312 are respectively formed on the second sub-dielectric substrate 1326. The orthographic projection of the first radiator 1311 on the second sub-dielectric substrate 1326 covers the orthographic projection of the slot 13251 corresponding to the antenna element 131 on the second sub-dielectric substrate 1326, thereby enabling the radio frequency signal in the waveguide cavity 1327 to couple to the first radiator 1311. The beam control module 150 is connected to one of the first radiators 1311 and the second radiator 1312 through the feed bias circuit 1328, and then connected to the electronic control element 1313 through the radiator, so as to control the switching state of the electronic control element 1313 by sending control signals to the electronic control element 1313. For example, in this embodiment, the beam control module 150 is connected to the second radiator 1312 through the feed bias circuit 1328, and connected to the electronic control element 1313 through the second radiator 1312. The feed bias circuit 1328 can reduce the interference between the control signal and the radio frequency signal in the radiator, and ensure the working reliability of the antenna element 131.

[0080] In its specific implementation, the reconfigurable antenna subarray 130 includes an isolation hole 1329 that sequentially penetrates the first sub-metal layer 1324, the first sub-dielectric substrate 1323, the second sub-metal layer 1325, and the second sub-dielectric substrate 1326. A feed bias circuit 1328 can be disposed within this isolation hole 1329, and the feed bias circuit 1328 is insulated from the first sub-metal layer 1324 and the second sub-metal layer 1325. This design facilitates the connection between the feed bias circuit 1328, the beam control module 150, and the second radiator 1312, and also saves space occupied by the feed bias circuit 1328 on the first sub-dielectric substrate 1323 or the second sub-dielectric substrate 1326, thereby helping to reduce the size of the reconfigurable antenna subarray 130.

[0081] Figure 16 is a top view of an antenna 100 provided in an embodiment of this application. Referring to Figure 16, according to the aforementioned embodiment, the feed network 110 of the antenna 100 and the subarray feed network 132 of the reconfigurable antenna subarray 130 can respectively adopt a substrate integrated waveguide structure, and the phase shifting unit 120 adopts the form of a liquid crystal phase shifting unit. For each phase shifting unit 120, the input terminals of the first transmission line (not shown in the figure) and the second transmission line 122 of the phase shifting unit 120 are respectively connected to the output terminal of the feed network 110, and the output terminals of the first transmission line and the second transmission line 122 of the phase shifting unit 120 are respectively connected to the reconfigurable antenna subarray 130.

[0082] As mentioned earlier, both the first metal layer of the feed network 110 and the first sub-metal layer of the subarray feed network 132 can be ground planes. Therefore, with the first transmission line being a ground plane and the second transmission line 122 being a microstrip line, the first metal layer, the first transmission line, and the first sub-metal layer can be a single integrated structure. One end of the second transmission line 122 is connected to the output of the feed network 110 via a waveguide microstrip conversion structure 1222, and the other end of the second transmission line 122 is connected to the sub-input terminal 1321 of the subarray feed network 132 via another waveguide microstrip conversion structure 1222, thereby enabling the transmission of radio frequency signals. This design effectively improves the overall integration of the antenna and reduces the difficulty of antenna fabrication and assembly.

[0083] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An antenna, characterized in that, It includes a feed network, multiple phase-shifting elements, and multiple reconfigurable antenna subarrays, wherein: The power supply network includes one input terminal and multiple output terminals; Each phase-shifting unit is connected between an output terminal of the feed network and a reconfigurable antenna subarray. The phase-shifting unit is used to adjust the phase of the radio frequency signal output by the feed network and then output it to the reconfigurable antenna subarray. The phase-shifting unit includes a first transmission line, a second transmission line, and a liquid crystal layer. The liquid crystal layer is disposed between the first transmission line and the second transmission line. The physical length of the first transmission line and the physical length of the second transmission line are L, and the waveguide wavelength of the first transmission line and the second transmission line is λg. L and λg satisfy: L≤1 / 4λg. The reconfigurable antenna subarray includes multiple 1-bit antenna elements.

2. The antenna as described in claim 1, characterized in that, The phase-shifting unit further includes a first substrate and a second substrate. A receiving groove is provided on one side surface of the first substrate, and the second substrate covers the side surface of the first substrate where the receiving groove is provided. The liquid crystal layer is filled in the receiving groove, the first transmission line is disposed on the first substrate, and the second transmission line is disposed on the second substrate.

3. The antenna as described in claim 2, characterized in that, The first transmission line is disposed at the bottom of the receiving groove; or, The first transmission line is disposed on the side surface of the first substrate facing away from the second substrate.

4. The antenna as described in claim 2 or 3, characterized in that, The second transmission line is disposed on the surface of the second substrate facing the first substrate; or, The second transmission line is disposed on the side surface of the second substrate facing away from the first substrate.

5. The antenna as described in any one of claims 1-4, characterized in that, The first transmission line is a ground plane, and the second transmission line is a microstrip line.

6. The antenna as described in any one of claims 1-4, characterized in that, The first transmission line and the second transmission line are parallel double lines.

7. The antenna as described in any one of claims 1-6, characterized in that, The first transmission line has one or more first protrusions on the side facing the second transmission line, and the second transmission line has one or more second protrusions on the side facing the first transmission line.

8. The antenna as described in any one of claims 1-7, characterized in that, The antenna unit includes a first radiator, a second radiator, and an electronic control element, wherein the electronic control element is connected between the first radiator and the second radiator.

9. The antenna as described in any one of claims 1-8, characterized in that, The reconfigurable antenna subarray includes a subarray feed network, which includes a first subdielectric substrate, a first submetal layer, and a second submetal layer. The first submetal layer and the second submetal layer are respectively disposed on two opposite surfaces of the first dielectric substrate. The first sub-dielectric substrate is provided with a first column of vias and a second column of vias. The first column of vias and the second column of vias are arranged opposite to each other, and the first column of vias and the second column of vias each include a plurality of metal vias arranged at intervals along a first direction. The first column of vias, the second column of vias, the first sub-metal layer, and the second sub-metal layer enclose a waveguide cavity, and the waveguide cavity connects the phase shifting unit and the antenna unit.

10. The antenna as claimed in claim 9, characterized in that, The reconfigurable antenna subarray further includes a second sub-dielectric substrate, which is disposed on the side of the second sub-metal layer opposite to the first sub-dielectric substrate; a plurality of antenna elements are disposed on the second sub-dielectric substrate along the first direction, and the orthographic projection of the plurality of antenna elements on the second sub-dielectric substrate is located within the orthographic projection of the waveguide cavity on the surface of the second sub-dielectric substrate; The second sub-metal layer is provided with a plurality of slots spaced apart along the first direction, and the plurality of slots are respectively positioned opposite to the plurality of antenna elements. Each slot is used to couple the signal in the waveguide cavity to the corresponding antenna element.

11. The antenna according to any one of claims 1-10, characterized in that, A power supply transmission line is formed between each input terminal and each of the output terminals, and at least two of the power supply transmission lines have different physical lengths.

12. A communication device, characterized in that, It includes a radio frequency device and an antenna as described in any one of claims 1-11, wherein the radio frequency device is connected to the antenna.

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