Method, system and equipment for driving liquid crystal phased array based on mixed voltage waveform

Abstract

The invention discloses a method, system and device for driving a liquid crystal phased array based on a mixed voltage waveform, and the method comprises the steps: driving the liquid crystal phased array through a first type of voltage signals, so as to enable liquid crystal molecules to deflect; the first type of voltage signal is used for representing a signal that the voltage jumps instantaneously; detecting the inclination angle of the liquid crystal molecules in real time; when the detected inclination angle reaches the preset maximum inclination angle, a second type of voltage signal is switched to drive the liquid crystal phased array, so that the liquid crystal molecules are recovered; the second type of voltage signal is used for representing a signal of which the voltage linearly changes along with time; and recovering to a preset initial inclination angle according to the detected inclination angle, and continuing to execute the step of driving the liquid crystal phased array by using the first type of voltage signals so as to deflect the liquid crystal molecules.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and particularly to a method, system, and device for driving a liquid crystal phased array based on a hybrid voltage waveform. Background Art

[0002] Antennas based on liquid crystal phased arrays (LCPA, Liquid Crystal Phased Array) provide a highly promising solution for low-altitude communication and satellite direct connection due to their advantages of low cost, low power consumption, and easy integration.

[0003] In a liquid crystal phased array, the liquid crystal layer needs to have a certain thickness to achieve the phase regulation function of radio frequency signals. However, the thickness of the liquid crystal layer affects the response speed of the liquid crystal phased array. The greater the thickness of the liquid crystal layer, the slower the response. Moreover, due to the inherent high viscosity characteristics of liquid crystal materials, the response speed of the liquid crystal phased array is also relatively slow, which cannot meet the requirements of low latency for low-altitude communication and satellite direct connection. Summary of the Invention

[0004] An object of the present invention is to propose a method, system, medium, and device for driving a liquid crystal phased array based on a hybrid voltage waveform in view of the above-mentioned deficiencies of the prior art, and this object is achieved through the following technical solutions.

[0005] A first aspect of the present invention proposes a method for driving a liquid crystal phased array based on a hybrid voltage waveform. Liquid crystal molecules for regulating the phase of radio frequency signals are provided in the liquid crystal phased array, and the method includes:

[0006] Driving the liquid crystal phased array with a first type of voltage signal to deflect the liquid crystal molecules; the first type of voltage signal is used to represent a signal with an instantaneous voltage jump.

[0007] Real-time detecting the tilt angle of the liquid crystal molecules.

[0008] According to the detected tilt angle reaching a preset maximum tilt angle, switching to a second type of voltage signal to drive the liquid crystal phased array to restore the liquid crystal molecules; the second type of voltage signal is used to represent a signal with a linearly changing voltage over time.

[0009] According to the detected tilt angle restoring to a preset initial tilt angle, continuing to execute the step of driving the liquid crystal phased array with the first type of voltage signal to deflect the liquid crystal molecules.

[0010] The second aspect of the present invention proposes a system for driving a liquid crystal phased array based on a hybrid voltage waveform. Liquid crystal molecules for regulating the phase of radio frequency signals are provided in the liquid crystal phased array. The system includes: an inclination detection device, a wave controller, and a control device. The control device is electrically connected to the inclination detection device and the wave controller respectively, and the wave controller is electrically connected to the liquid crystal phased array;

[0011] The inclination detection device is configured to collect relevant parameters of the liquid crystal phased array and transmit the relevant parameters to the control device;

[0012] The control device is configured to determine the tilt angle of the liquid crystal molecules according to the received relevant parameters, and control the wave controller to provide a first type of voltage signal or a second type of voltage signal for the liquid crystal phased array according to the change of the tilt angle of the liquid crystal molecules; the first type of voltage signal is used to represent a signal with an instantaneous voltage jump at the moment of voltage occurrence; the second type of voltage signal is used to represent a signal with a linear voltage change over time.

[0013] The third aspect of the present invention proposes an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. The processor executes the program to implement the method as described in the first aspect.

[0014] The fourth aspect of the present invention proposes a computer-readable storage medium, on which a computer program is stored. The program is executed by a processor to implement the method as described in the first aspect.

[0015] Based on the above-mentioned method, system, medium and device for driving a liquid crystal phased array based on a hybrid voltage waveform, the present invention has the following beneficial effects or advantages:

[0016] By using the first type of voltage signal to drive the liquid crystal phased array to deflect the liquid crystal molecules, the first type of voltage signal belongs to the signal with an instantaneous voltage jump, which can quickly break the balance between the liquid crystal molecules and accelerate the deflection process of the liquid crystal molecules, thereby shortening the rise time of the liquid crystal molecules. When it is detected that the tilt angle of the liquid crystal molecules rises to the maximum tilt angle, switch to the second type of voltage signal to drive the liquid crystal phased array to restore the liquid crystal molecules. The second type of voltage signal belongs to the signal with a linear change, and its change is relatively smooth, which can accelerate the descent process of the liquid crystal molecules and ensure that the descent process of the liquid crystal molecules is more stable, avoiding instability caused by too drastic changes. It can be seen that by using a hybrid voltage waveform to drive the liquid crystal phased array, the response time of the liquid crystal phased array can be effectively shortened and the response speed can be improved, meeting the requirements of low latency for low-altitude communication and satellite direct connection. Description of the Drawings

[0017] The accompanying drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 is a schematic structural diagram of a system for driving a liquid crystal phased array based on a hybrid voltage waveform according to an exemplary embodiment of the present invention;

[0019] Figure 2 is a schematic diagram of inclination detection according to an exemplary embodiment of the present invention;

[0020] Figure 3 is another schematic diagram of inclination detection according to an exemplary embodiment of the present invention;

[0021] Figure 4 is a flowchart of an embodiment of a method for driving a liquid crystal phased array based on a hybrid voltage waveform according to an exemplary embodiment of the present invention;

[0022] Figure 5 is a schematic diagram of a liquid crystal inclination response curve of different voltage waveforms according to an exemplary embodiment of the present invention;

[0023] Figure 6 is a schematic hardware structure diagram of an electronic device according to an exemplary embodiment of the present invention;

[0024] Figure 7 is a schematic structural diagram of a storage medium according to an exemplary embodiment of the present invention. Detailed Embodiments

[0025] Here, the exemplary embodiments will be described in detail, and the examples are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. On the contrary, they are merely examples of systems and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0026] The terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms of "a", "the", and "said" used in the present invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0027] It should be understood that although terms such as first, second, and third may be used in the present invention to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of the present invention, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to a determination".

[0028] With the global rollout of commercial fifth-generation (5G) systems, the research focus has gradually shifted towards sixth-generation (6G) systems, which are expected to achieve another major leap in the field of communications. The 6G network will not only further enhance the performance of terrestrial communications but also enable global seamless coverage through non-terrestrial networks such as low Earth orbit (LEO) satellites, especially in areas where terrestrial networks are difficult to cover, such as remote regions, oceans, and polar regions. Due to its relatively low orbital altitude (usually between 500 and 2000 kilometers), LEO satellites can significantly reduce signal transmission latency, provide higher data transmission rates, and wider coverage. Compared with geostationary orbit (GEO) satellites, the latency of LEO satellites is typically only 20 - 50 milliseconds, far lower than the 500-millisecond latency of GEO satellites, which gives LEO satellites significant advantages in areas such as real-time communication, the Internet of Things, and emergency communication.

[0029] With the deployment of giant constellations of Low Earth Orbit (LEO) satellites, the low-altitude economy will witness rapid development. Low-altitude communication will become one of the new frontiers for connectivity towards 6G, complementing terrestrial networks and providing unlimited connectivity anywhere, thus helping to bridge the digital divide. Satellite direct connection technology is a key technology in low-orbit satellite communication, which allows user equipment (such as smartphones, vehicle-mounted terminals, Internet of Things devices, etc.) to directly establish a connection with satellites without relaying through terrestrial base stations or other intermediate devices. The realization of satellite direct connection technology relies on efficient beamforming and fast phase-shifting technologies to ensure that signals can be accurately directed towards user equipment and achieve low-latency and high-reliability communication. However, although low-altitude communication and satellite direct connection technology have great potential in promoting the development of the low-altitude economy and enhancing global connectivity, there are still many technical bottlenecks in achieving efficient and low-latency communication. Especially in low-altitude communication and satellite direct connection systems, how to ensure that communication equipment can respond quickly and accurately control the beam has become one of the key factors affecting system performance. Facing the increasing demand for communication capacity and real-time performance, traditional mechanical scanning antennas and semiconductor phased array antennas both have obvious deficiencies in low-altitude communication and satellite direct connection scenarios: mechanical scanning antennas have a slow response speed and are difficult to meet the real-time tracking requirements; although semiconductor phased array antennas have a fast response speed, they are costly and difficult to deploy on a large scale.

[0030] Liquid crystal materials are materials with dielectric anisotropy. By applying an external bias voltage, the orientation of liquid crystal molecules can be changed, causing the liquid crystal molecules to deflect towards the direction of the electric field, thereby changing the relative dielectric constant of the liquid crystal. Using a dielectric substrate with liquid crystal materials as the phase modulation unit, the dynamic adjustment of the reflection phase can be achieved by modulating its relative dielectric constant. Furthermore, by utilizing the phase modulation mechanism of the antenna elements of the liquid crystal phased array, the antenna beamforming function can ultimately be realized. The antenna of the liquid crystal phased array provides a highly promising solution for low-altitude communication with its advantages of low cost, low power consumption, and easy integration. However, due to the inherent high viscosity characteristics of liquid crystal materials and the requirement for a certain thickness of the liquid crystal layer to achieve phase control, the response speed of the liquid crystal phased array is relatively slow and difficult to meet the strict requirements of low-altitude communication for low latency. Therefore, how to effectively reduce the response time of the liquid crystal phased array has become the key technical challenge to promote its application in the fields of low-altitude communication and satellite direct connection.

[0031] Based on this, the present invention proposes a scheme for driving a liquid crystal phased array based on a hybrid voltage waveform, which can effectively improve the response speed of the liquid crystal phased array by adopting a hybrid voltage waveform to drive the liquid crystal phased array.

[0032] The following uses specific embodiments to elaborate in detail on the scheme for driving a liquid crystal phased array based on a hybrid voltage waveform proposed by the present invention. Those skilled in the art can understand that liquid crystal molecules for phase modulation of radio frequency signals are provided in the liquid crystal phased array.

[0033] Figure 1 FIG. 2 is a schematic structural diagram of a system for driving a liquid crystal phased array based on a hybrid voltage waveform according to an exemplary embodiment of the present invention, including: an inclination angle detection device, a wave controller, and a control device. The control device is electrically connected to the inclination angle detection device and the wave controller respectively, and the wave controller is electrically connected to the liquid crystal phased array.

[0034] Among them, the inclination angle detection device is used to collect relevant parameters of the liquid crystal phased array and transmit the relevant parameters to the control device;

[0035] The control device is used to determine the tilt angle of the liquid crystal molecules according to the received relevant parameters, and control the wave controller to provide a first type of voltage signal or a second type of voltage signal for the liquid crystal phased array according to the change of the tilt angle of the liquid crystal molecules; the first type of voltage signal is used to represent a signal with an instantaneous voltage jump; the second type of voltage signal is used to represent a signal with a linearly changing voltage over time.

[0036] Specifically, in the initial state where no driving signal is applied to the liquid crystal phased array, the control device controls the wave controller to apply a first type of voltage signal to the liquid crystal phased array. The inclination angle detection device starts to collect relevant parameters of the liquid crystal phased array. The control device calculates the tilt angle of the liquid crystal molecules according to the relevant parameters collected by the inclination angle detection device in real time. When the tilt angle rises to the maximum tilt angle, the control device controls the wave controller to apply a second type of voltage signal to the liquid crystal phased array. When the tilt angle returns to the initial tilt angle, the control device continues to control the wave controller to apply a first type of voltage signal to the liquid crystal phased array, and so on.

[0037] The relevant parameters collected by the inclination angle detection device are parameters for calculating the tilt angle of the liquid crystal.

[0038] In an alternative embodiment, as Figure 2 shown, the inclination angle detection device may include: a vector network analyzer, a transmitting antenna, and a receiving antenna. The vector network analyzer is electrically connected to the transmitting antenna and the receiving antenna respectively, so as to measure the scattering parameters of the liquid crystal phased array using the vector network analyzer to realize the calculation of the tilt angle of the liquid crystal.

[0039] Among them, the vector network analyzer is used to send a radio frequency signal to the transmitting antenna, so that the transmitting antenna converts the radio frequency signal into an electromagnetic wave and emits it to the liquid crystal phased array, and receives the reflected radio frequency signal converted by the receiving antenna based on the received reflected electromagnetic wave. The scattering parameters are determined based on the reflected radio frequency signal and the original radio frequency signal, and the scattering parameters are transmitted to the control device.

[0040] In this embodiment, the scattering parameters reflect the scattering performance of the signal in the liquid crystal phased array, that is, the S parameters of the vector network analyzer, which can be the reflection coefficient S 11 or the transmission coefficient S 21。The control device can calculate the tilt angle of the liquid crystal molecules based on the scattering parameters fed back by the vector network analyzer.

[0041] Reflection coefficient S 11 Indicates the proportion of the incident wave reflected at the port, that is, how much of the wave incident from port 1 is reflected back to port 1. Transmission coefficient S 21 Indicates the proportion of the incident wave transmitted from one port to another port, that is, how much of the wave incident from port 1 is transmitted to port 2.

[0042] In another alternative embodiment, as Figure 3 shown, the tilt angle detection device includes: a photoelectric sensor and a light source. The light source is located on the front of the liquid crystal phased array. The photoelectric sensor is used to collect the transmitted light intensity or the reflected light intensity of the liquid crystal phased array and transmit the transmitted light intensity or the reflected light intensity to the control device.

[0043] It should be noted that if the photoelectric sensor measures the transmitted light, the photoelectric sensor is located on the back of the liquid crystal phased array, as Figure 3 shown, then the photoelectric sensor collects the transmitted light intensity of the liquid crystal phased array; and if the photoelectric sensor measures the reflected light, the photoelectric sensor is located on the front of the liquid crystal phased array, then the photoelectric sensor collects the reflected light intensity of the liquid crystal phased array.

[0044] In this embodiment, the transmitted light intensity or the reflected light intensity collected by the photoelectric sensor can reflect the deflection state of the liquid crystal molecules under the action of the electric field. Therefore, the control device can calculate the tilt angle of the liquid crystal molecules based on the transmitted light intensity or the reflected light intensity collected by the photoelectric sensor.

[0045] Figure 4 This is a flowchart of an embodiment of a method for driving a liquid crystal phased array based on a hybrid voltage waveform according to an exemplary embodiment of the present invention. Based on the above Figure 1 shown system, as Figure 4 shown, the method for driving a liquid crystal phased array based on a hybrid voltage waveform includes the following steps:

[0046] Step 101: Drive the liquid crystal phased array with a first type of voltage signal to deflect the liquid crystal molecules. The first type of voltage signal is used to represent a signal with an instantaneous voltage jump.

[0047] Step 102: Detect the tilt angle of the liquid crystal molecules in real time.

[0048] Step 103: According to the detected tilt angle reaching a preset maximum tilt angle, switch to a second type of voltage signal to drive the liquid crystal phased array to restore the liquid crystal molecules. The second type of voltage signal is used to represent a signal with a linear voltage change over time.

[0049] Step 104: Restore to the preset initial inclination angle according to the detected inclination angle, and continue to execute Step 101.

[0050] Among them, the response process of liquid crystal molecules is periodic. In one response cycle, the liquid crystal molecules start to deflect from the initial inclination angle. When the maximum inclination angle is reached, they gradually recover until they return to the initial inclination angle and reach stability. It can be seen that each response cycle of liquid crystal molecules involves the deflection rising stage and the deflection falling stage of liquid crystal molecules, so the response time is the sum of the rising time and the falling time.

[0051] The traditional liquid crystal phased array driving method uses a single type of driving waveform, which is difficult to meet the requirements of rapid deflection and stable holding of liquid crystal molecules, thus restricting the improvement of the response speed of liquid crystal molecules.

[0052] In the embodiment of the present application, by using the first type of voltage signal to drive the liquid crystal phased array to deflect the liquid crystal molecules. Since the first type of voltage signal belongs to the signal of instantaneous voltage jump, it can quickly break the balance between liquid crystal molecules and accelerate the deflection process of liquid crystal molecules, thereby shortening the rising time of liquid crystal molecules. When it is detected that the inclination angle of liquid crystal molecules rises to the maximum inclination angle, switch to the second type of voltage signal to drive the liquid crystal phased array to make the liquid crystal molecules recover. Since the second type of voltage signal belongs to the signal of linear change, its change is relatively smooth, which can accelerate the deflection recovery process of liquid crystal molecules and ensure a more stable recovery, avoiding the instability caused by too drastic changes. It can be seen that by using the hybrid voltage waveform to drive the liquid crystal phased array, the response time of the liquid crystal phased array can be effectively shortened, the response speed can be improved, and the requirements of low-latency for low-altitude communication and satellite direct connection can be met.

[0053] In an alternative embodiment, the first type of voltage signal may include a square wave signal, a rectangular wave signal, a pulse signal, etc. These voltage waveforms all belong to the transient type of voltage signals; the second type of voltage signal may include a triangular wave signal, a sawtooth wave signal, etc. These voltage waveforms all belong to the linear type of voltage signals.

[0054] Next, three types of voltage waveforms are used to drive the liquid crystal phased array respectively, namely, the sine wave voltage signal belonging to the non-linear type, the triangular wave voltage signal belonging to the linear type, and the square wave voltage signal belonging to the transient type, and the driving waveform is selected by comparing the liquid crystal inclination angle response simulation curves using these three voltage waveforms.

[0055] To ensure the consistency of experimental simulation, the parameters of each voltage waveform are kept the same, that is, the driving frequency f = 1 kHz is used as the period, and the voltage amplitudes V high and V low are +5V and -5V respectively, and the corresponding voltage signals are generated through the following formula:

[0056] Sine wave voltage signal:

[0057]

[0058] Triangular wave voltage signal:

[0059]

[0060] Square wave voltage signal:

[0061]

[0062] The Euler method is used to numerically simulate the tilt angle response of liquid crystal molecules. According to the high and low levels of the voltage signal, the liquid crystal tilt angle θ(t) is updated at different time steps. For the high-level voltage, the liquid crystal tilt angle gradually increases, and the simulation calculation formula follows the following formula:

[0063]

[0064] where θ m represents the maximum tilt angle of the liquid crystal molecules; t(i) - t(i - 1) represents the time step; represents the rise time of the liquid crystal molecules, represents the fall time of the liquid crystal molecules, θ p represents the initial tilt angle of the liquid crystal molecules, V th represents the voltage threshold of the drive signal, V represents the voltage of the drive signal, γ1 represents the viscosity coefficient of the liquid crystal molecules, d represents the thickness of the liquid crystal layer in the liquid crystal phased array, k 33 represents the elastic coefficient of the liquid crystal molecules.

[0065] It should be noted that the calculation formulas for the rise time and fall time of the liquid crystal molecules given above are all derived from the Ericksen-Leslie equation considering the effect of the pre-tilt angle (i.e., the initial tilt angle of the liquid crystal molecules is not 0).

[0066] For the low-level voltage, the liquid crystal tilt angle gradually decays, and the simulation calculation formula follows the following formula:

[0067]

[0068] where,

[0069] During the simulation process, the simulation parameters are set as: d = 2μm, θ p = π / 8, θ m = π / 2, γ1 = 1×10 -4Pa·s, k 33 = 1×10 -12 N·m, V th = 1.5V.

[0070] As Figure 5 shown, by performing numerical simulation calculations with the above simulation parameters, the inclination response curves under a square-wave voltage signal drive, the inclination response curves under a sine-wave voltage signal drive, and the inclination response curves under a triangular-wave voltage signal drive can be obtained.

[0071] By analyzing the liquid crystal inclination response curves, determine the time points when the liquid crystal inclination reaches 90% and 10% of the maximum inclination angle θ m , and the time point when the liquid crystal inclination first reaches the maximum inclination angle θ m . According to these time points, calculate the rise time and fall time of the liquid crystal inclination response under different drive waveforms respectively, and obtain the rise time and fall time as shown in Table 1.

[0072] Drive voltage waveform Rise time (seconds) Fall time (seconds) Square wave 0.000015 0.00063 Sine wave 0.000085 0.00059 Triangle wave 0.00033 0.000055

[0073] Table 1

[0074] It can be seen from Table 1 that the time for the liquid crystal molecules to deflect and rise is the shortest under square-wave drive, and the time for the liquid crystal molecules to deflect and fall is the shortest under triangular-wave drive.

[0075] Based on the above experimental simulation results, by applying a square-wave voltage signal during the rising stage of the liquid crystal molecule deflection to accelerate its deflection, and applying a triangular-wave voltage signal during the falling stage of the liquid crystal molecule deflection to achieve fast stability, the liquid crystal response time can be significantly shortened by adopting a hybrid voltage waveform drive scheme.

[0076] It should be noted that in the actual application solution, the signal parameters of the first type of voltage signal and the signal parameters of the second type of voltage signal can be set according to the tolerance of the liquid crystal material. For example, for the amplitude of the first type of voltage signal, it can be set to 90% of the upper limit of the voltage that the liquid crystal material can withstand. This amplitude can quickly reach the maximum inclination angle on the premise of ensuring the stability of the liquid crystal. Secondly, the settings of parameters such as frequency and duty cycle also follow the principle of the liquid crystal material's tolerance for specific settings.

[0077] In an alternative embodiment, as described above Figure 2 shown, for the process of real-time detecting the tilt angle of liquid crystal molecules, it may include:

[0078] Measuring the scattering parameters of the liquid crystal phased array by a vector network analyzer, determining the dielectric constant of the liquid crystal molecules based on the scattering parameters, and obtaining the tilt angle of the liquid crystal molecules by using the dielectric constant.

[0079] As described above, the scattering parameters reflect the scattering performance of signals in the liquid crystal phased array. By using the scattering parameters, the electromagnetic properties of the liquid crystal material, such as the dielectric constant, can be deduced. Since the dielectric constant is related to the tilt angle of the liquid crystal molecules, the tilt angle can be solved through the deduced dielectric constant.

[0080] The dielectric constant of liquid crystal materials is usually anisotropic, that is, the dielectric constants parallel and perpendicular to the long axis of the molecules are different. The change in the tilt angle of liquid crystal molecules will cause a change in the dielectric constant. The relationship between the dielectric constant and the tilt angle can be expressed as:

[0081] Where, is the tilt angle of the liquid crystal molecules, is the dielectric constant of the liquid crystal material, and are the dielectric constants parallel and perpendicular to the long axis of the molecules, respectively.

[0083] By solving this equation through numerical methods (such as Newton iteration method), the tilt angle θ of the liquid crystal molecules can be obtained.

[0084] It can be seen that every time the scattering parameters are measured by the vector network analyzer, the tilt angle can be solved once. Thus, by using the scattering parameters measured in real time by the vector network analyzer, the change in the tilt angle of the liquid crystal molecules can be obtained in real time.

[0085] In this embodiment, the dielectric constant of the liquid crystal material is deduced by using the scattering parameters measured by the vector network analyzer. Since the dielectric constant is related to the tilt angle of the liquid crystal molecules, the tilt angle can be solved through the deduced dielectric constant.

[0086] In an alternative embodiment, for the process of determining the dielectric constant of liquid crystal molecules based on the scattering parameters, it may include:

[0087] Obtain a preset electromagnetic model, which is a mathematical model used to describe the interaction between electromagnetic waves and liquid crystal materials. The dielectric constant of the liquid crystal material is included in the electromagnetic model. Fit the electromagnetic model with the preset numerical optimization algorithm and the scattering parameters to obtain the dielectric constant of the liquid crystal molecules.

[0088] Since the liquid crystal phased array is a multi-layer dielectric structure, which includes a top substrate, a top alignment layer, a liquid crystal layer, a bottom alignment layer, and a bottom substrate that are sequentially adhered. Considering the propagation and reflection of electromagnetic waves in multi-layer dielectrics, the electromagnetic model can be based on Maxwell's equations.

[0089] Use a preset numerical optimization method (such as the least squares method) to fit the scattering parameters measured by a vector network analyzer with an electromagnetic model. By adjusting the dielectric constant in the electromagnetic model, the error between the scattering parameters predicted by the electromagnetic model and the scattering parameters measured by the vector network analyzer is minimized.

[0090] In another alternative embodiment, as described above Figure 3 As shown, for the process of real-time detecting the tilt angle of liquid crystal molecules, it may include:

[0091] Collect the transmitted light intensity or reflected light intensity of the liquid crystal phased array through a photoelectric sensor, and use a preset relationship between the optical signal and the tilt angle to calculate the tilt angle corresponding to the transmitted light intensity or reflected light intensity as the tilt angle of the liquid crystal molecules.

[0092] If the liquid crystal phased array realizes the phase control of the radio frequency signal in a transmission mode, then the photoelectric sensor collects the transmitted light intensity of the liquid crystal phased array. If the liquid crystal phased array realizes the phase control of the radio frequency signal in a reflection mode, then the photoelectric sensor collects the reflected light intensity of the liquid crystal phased array.

[0093] Since the tilt angle of the liquid crystal molecules affects the polarization state or transmission characteristics of light, the tilt angle of the liquid crystal molecules can be indirectly deduced by detecting the change of light through the photoelectric sensor.

[0094] The relationship between the optical signal and the tilt angle used in this embodiment can be expressed as:

[0095] I(θ) = I0 * sin 2 (2θ)

[0096] Wherein, I0 is the initial light intensity, and θ is the tilt angle of the liquid crystal molecules.

[0097] Figure 6 This is a hardware structure diagram of an electronic device shown according to an exemplary embodiment of the present invention. The electronic device includes: a communication interface 401, a processor 402, a machine-readable storage medium 403, and a bus 404; wherein, the communication interface 401, the processor 402, and the machine-readable storage medium 403 complete mutual communication through the bus 404. The processor 402 can execute the method of driving the liquid crystal phased array based on the hybrid voltage waveform described above by reading and executing the machine-executable instructions corresponding to the control logic of the method of driving the liquid crystal phased array based on the hybrid voltage waveform in the machine-readable storage medium 403. The specific content of this method can be referred to the above embodiment and will not be repeated here.

[0098] The machine-readable storage medium 403 mentioned in the present invention can be any electronic, magnetic, optical or other physical storage system that can contain or store information, such as executable instructions, data, and so on. For example, the machine-readable storage medium can be: volatile memory, non-volatile memory or similar storage media. Specifically, the machine-readable storage medium 403 can be RAM (Random Access Memory), flash memory, a storage drive (such as a hard disk drive), any type of storage disk (such as an optical disk, DVD, etc.), or similar storage media, or a combination thereof.

[0099] An embodiment of the present invention also provides a computer-readable storage medium corresponding to the method for driving a liquid crystal phased array based on a hybrid voltage waveform provided in the foregoing embodiment. Please refer to Figure 7 As shown, the computer-readable storage medium shown is an optical disk 30, on which a computer program (i.e., a program product) is stored. When the computer program is run by a processor, it will execute the method for driving a liquid crystal phased array based on a hybrid voltage waveform provided in any of the foregoing embodiments.

[0100] It should be noted that examples of the computer-readable storage medium may also include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory, or other optical and magnetic storage media, which will not be elaborated here one by one.

[0101] The computer-readable storage medium provided in the above embodiment of the present invention and the method for driving a liquid crystal phased array based on a hybrid voltage waveform provided in the embodiment of the present invention are based on the same inventive concept and have the same beneficial effects as the method adopted, run or implemented by the application program stored therein.

[0102] Those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include known common knowledge or conventional technical means in the technical field not disclosed by the present invention. The specification and examples are only to be considered as exemplary, and the true scope and spirit of the present invention are pointed out by the following claims.

[0103] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, commodity or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, commodity or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, commodity or device comprising said element.

[0104] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for driving a liquid crystal phased array based on a hybrid voltage waveform, characterized in that, The liquid crystal phased array is provided with liquid crystal molecules for phase modulation of radio frequency signals. The method includes: Driving the liquid crystal phased array with a first type of voltage signal to deflect the liquid crystal molecules; the first type of voltage signal is used to represent a signal with an instantaneous voltage jump. Real-time detecting the tilt angle of the liquid crystal molecules. According to the detected tilt angle reaching a preset maximum tilt angle, switching to a second type of voltage signal to drive the liquid crystal phased array to restore the liquid crystal molecules; the second type of voltage signal is used to represent a signal with a linearly changing voltage over time. According to the detected tilt angle restoring to a preset initial tilt angle, continue to execute the step of driving the liquid crystal phased array with the first type of voltage signal to deflect the liquid crystal molecules.

2. The method according to claim 1, characterized in that The first type of voltage signal includes any one of a square wave signal, a rectangular wave signal, and a pulse signal. The second type of voltage signal includes any one of a triangular wave signal and a sawtooth wave signal.

3. The method according to claim 1, wherein The real-time detecting the tilt angle of the liquid crystal molecules includes: Measuring the scattering parameters of the liquid crystal phased array by a vector network analyzer. Determining the dielectric constant of the liquid crystal molecules based on the scattering parameters. Obtaining the tilt angle of the liquid crystal molecules by using the dielectric constant.

4. The method according to claim 3, wherein The determining the dielectric constant of the liquid crystal molecules based on the scattering parameters includes: Obtaining a preset electromagnetic model, which is a mathematical model for describing the interaction between electromagnetic waves and liquid crystal materials, and the electromagnetic model includes the dielectric constant of the liquid crystal material. Fitting the electromagnetic model with the preset numerical optimization algorithm and the scattering parameters to obtain the dielectric constant of the liquid crystal molecules.

5. The method according to claim 1, characterized in that The real-time detecting the tilt angle of the liquid crystal molecules includes: Collecting the transmitted light intensity or the reflected light intensity of the liquid crystal phased array by a photoelectric sensor. Calculating the tilt angle corresponding to the transmitted light intensity or the reflected light intensity as the tilt angle of the liquid crystal molecules by using a preset relationship between the optical signal and the tilt angle.

6. A system for driving a liquid crystal phased array based on a hybrid voltage waveform, characterized in that, The liquid crystal phased array is provided with liquid crystal molecules for phase modulation of radio frequency signals. The system includes: a tilt angle detection device, a wave controller, and a control device. The control device is electrically connected to the tilt angle detection device and the wave controller respectively, and the wave controller is electrically connected to the liquid crystal phased array. The tilt angle detection device is used to collect the relevant parameters of the liquid crystal phased array and transmit the relevant parameters to the control device. The control device is used to determine the tilt angle of the liquid crystal molecules according to the received relevant parameters, and control the wave controller to provide a first type of voltage signal or a second type of voltage signal for the liquid crystal phased array according to the change of the tilt angle of the liquid crystal molecules; the first type of voltage signal is used to represent a signal with an instantaneous voltage jump; the second type of voltage signal is used to represent a signal with a linearly changing voltage over time.

7. The system according to claim 6, characterized in that, The tilt angle detection device includes: a vector network analyzer, a transmitting antenna, and a receiving antenna. The vector network analyzer is electrically connected to the transmitting antenna and the receiving antenna respectively. The vector network analyzer is configured to send a radio frequency signal to the transmitting antenna, so that the transmitting antenna converts the radio frequency signal into an electromagnetic wave and transmits it to the liquid crystal phased array, and receive a reflected radio frequency signal obtained by the receiving antenna based on the received reflected electromagnetic wave, determine a scattering parameter based on the reflected radio frequency signal and the radio frequency signal, and transmit the scattering parameter to the control device.

8. The system according to claim 6, wherein The tilt angle detection device includes: a photoelectric sensor and a light source. The light source is located on the front surface of the liquid crystal phased array. The photoelectric sensor is configured to collect the transmitted light intensity or the reflected light intensity of the liquid crystal phased array, and transmit the transmitted light intensity or the reflected light intensity to the control device; If the photoelectric sensor measures transmitted light, the photoelectric sensor is located on the back surface of the liquid crystal phased array; If the photoelectric sensor measures reflected light, the photoelectric sensor is located on the front surface of the liquid crystal phased array.

9. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the program to implement the method according to any one of claims 1-5.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the method according to any one of claims 1-5.

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