Phased array antenna, scanning method thereof, and antenna system

Abstract

A phased array antenna, a scanning method therefor, and an antenna system. The phased array antenna includes multiple antenna elements and a liquid crystal phase shifter for phase calibration of the multiple antenna elements. The scanning method includes: applying a first wave-control voltage to the liquid crystal phase shifter and detecting the level values ​​of first received signals received by the multiple antenna elements; and continuously adjusting the first wave-control voltage using an artificial intelligence algorithm and detecting the level values ​​of second received signals received by the multiple antenna elements until the ratio of the first received signal level to the second received signal level is greater than or equal to a first threshold.

Description

Technical Field

[0001] This article relates to but is not limited to the field of communication technology, and in particular to a phased array antenna, a scanning method thereof, and an antenna system. Background Art

[0002] Nearly 80% of the world's land area and 95% of its oceans are difficult or impossible to reach with terrestrial networks. According to a survey by the Global System for Mobile Communications Association (GSMA), over 30% of the world's population lacks mobile communications services, and approximately 52% lacks broadband services. Numerous satellite network systems, including my country's StarNet, the United States' Starlink, and Russia's Sphere, are actively promoting satellite internet technology. Leveraging integrated space-ground networking and satellite communications, the last 10% of users on Earth can access the internet.

[0003] Corresponding to the broad prospects of the satellite market, the development of satellite ground terminal equipment has also entered a fast track. Low-cost liquid crystal phased array antennas are expected to replace traditional servo antenna systems and expensive transmitter and receiver (TR) component antenna systems, becoming a solution for popularizing satellite communication ground terminals. Summary of the Invention

[0004] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0005] An embodiment of the present disclosure provides an antenna control method, wherein the phased array antenna includes multiple antenna elements and a liquid crystal phase shifter for phase calibration of the multiple antenna elements. The scanning method includes: applying a first wave control voltage to the liquid crystal phase shifter and detecting the level values ​​of first received signals received by the multiple antenna elements; and continuously adjusting the first wave control voltage using an artificial intelligence algorithm and detecting the level values ​​of second received signals received by the multiple antenna elements until the ratio of the first received signal level value to the second received signal level value is greater than or equal to a first threshold value.

[0006] In some exemplary embodiments, the scanning method further comprises:

[0007] Dividing the to-be-scanned area of ​​the phased array antenna into a plurality of first sub-areas, adjusting the wave control voltage of the liquid crystal phase shifter to detect third received signal level values ​​received in the plurality of first sub-areas, and determining the first sub-area corresponding to the maximum third received signal level value;

[0008] A first subregion corresponding to the maximum third received signal level value is divided into multiple second subregions, and a wave control voltage of the liquid crystal phase shifter is adjusted to detect the received fourth received signal level values ​​in the multiple second subregions. When the ratio of the maximum third received signal level value to the maximum fourth received signal level value is less than a second threshold, the maximum fourth received signal level value is updated to the maximum third received signal level value, the second subregion corresponding to the maximum fourth received signal level value is updated to the first subregion corresponding to the maximum third received signal level value, and an operation of dividing the first subregion corresponding to the maximum third received signal level value into multiple second subregions is triggered until the ratio of the maximum third received signal level value to the maximum fourth received signal level value is greater than or equal to the second threshold.

[0009] In some exemplary embodiments, the scanning method further includes: dividing the area to be scanned by the phased array antenna into a plurality of first sub-areas, comprising: evenly dividing the area to be scanned by the phased array antenna into the plurality of first sub-areas along a vertical direction;

[0010] The dividing the first sub-region corresponding to the maximum third received signal level value into a plurality of second sub-regions specifically includes: evenly dividing the area to be scanned by the phased array antenna into a plurality of first sub-regions along a vertical direction.

[0011] In some exemplary embodiments, the scanning method further includes: the second threshold is between 0.631 and 0.841.

[0012] In some exemplary embodiments, the scanning method further includes: the first threshold is between 0.841 and 0.944.

[0013] In some exemplary embodiments, the scanning method further includes: the artificial intelligence algorithm is a genetic algorithm or a particle swarm optimization algorithm.

[0014] In some exemplary embodiments, the scanning method further includes: the first received signal is a pilot signal, and the second received signal is a pilot signal.

[0015] In some exemplary embodiments, the scanning method further comprises:

[0016] Calculating a rough satellite position based on the position information of the phased array antenna and pre-installed satellite ephemeris information, and receiving satellite broadcast ephemeris based on the calculated rough satellite position;

[0017] When receiving satellite broadcast ephemeris, calculate the precise position of the satellite based on the received satellite broadcast ephemeris;

[0018] When no satellite broadcast ephemeris is received, the current wave control voltage is recorded as the first wave control voltage, and the current received signal level value is recorded as the first received signal level value, triggering the operation of continuously adjusting the first wave control voltage using the artificial intelligence algorithm.

[0019] In some exemplary embodiments, calculating a coarse satellite position based on the position information of the phased array antenna and pre-installed satellite ephemeris information, and receiving satellite broadcast ephemeris based on the calculated coarse satellite position, includes:

[0020] Acquiring position information and attitude information of the phased array antenna;

[0021] Calculate the satellite's rough position based on the acquired position information and attitude information as well as pre-installed satellite ephemeris information;

[0022] Calculating azimuth and elevation angle information of the phased array antenna and the satellite based on the calculated rough satellite position;

[0023] Satellite capture and satellite broadcast ephemeris reception are performed based on the calculated azimuth and elevation angle information and a preset antenna scanning angle and wave control voltage lookup table.

[0024] In some exemplary embodiments, when the connection between the phased array antenna and the satellite is interrupted, the scanning method further includes:

[0025] Record the received signal level value before the connection is interrupted as the fifth received signal level value, and record the current received signal level value as the sixth received signal level value;

[0026] When the ratio of the sixth received signal level value to the fifth received signal level value is less than a third threshold, the beam pointing of the phased array antenna is adjusted according to the inertial navigation acceleration information, and the adjusted beam control voltage is recorded as the first beam control voltage, triggering the operation of continuously adjusting the first beam control voltage using the artificial intelligence algorithm.

[0027] In some exemplary embodiments, the third threshold is between 0.707 and 0.891.

[0028] In some exemplary embodiments, adjusting the beam pointing of the phased array antenna according to inertial navigation acceleration information includes:

[0029] Performing time integration on the inertial navigation acceleration and converting the integration result into a navigation coordinate system to obtain angle information;

[0030] Calculating a correction angle of the phased array antenna according to the angle information, and converting the correction angle into a normal deflection angle;

[0031] The beam pointing direction of the phased array antenna is adjusted according to the normal deflection angle and a preset antenna scanning angle and beam control voltage lookup table.

[0032] In some exemplary embodiments, the fifth received signal is a pilot signal or a data signal, and the sixth received signal is a pilot signal or a data signal.

[0033] An embodiment of the present disclosure further provides a phased array antenna, comprising: a plurality of antenna array elements and a liquid crystal phase shifter for performing phase calibration on the plurality of antenna array elements, wherein the phased array antenna is scanned using the scanning method as described in any of the preceding items.

[0034] In some exemplary embodiments, the liquid crystal phase shifter includes any one or more of the following: a microstrip transmission line, a coplanar waveguide transmission line, and a periodic variable capacitor.

[0035] The embodiment of the present disclosure also provides an antenna system, comprising: a baseband system, an antenna feed system, and a beam control system, wherein: the baseband system is configured to perform baseband processing on a signal; the antenna feed system is configured to transmit and receive satellite signals; the antenna feed system comprises a phased array antenna, a combiner, a power splitter, a down converter, and an up converter; the phased array antenna comprises: a plurality of antenna elements and a liquid crystal phase shifter for performing phase calibration on the plurality of antenna elements; the combiner is connected to the down converter, the power splitter is connected to the up converter; the beam control The system is configured to drive and control the liquid crystal phase shifter. The wave control system includes a central control module, a voltage loading module, an inertial navigation module, a positioning module, and a posture detection module. The central control module is configured to receive data from the inertial navigation module, the positioning module, and the posture detection module, and calculate the wave control voltage required for the liquid crystal phase shifter to control the phased array antenna to scan according to the scanning method described in any of the preceding items. The voltage loading module is configured to output a corresponding wave control voltage to the liquid crystal phase shifter according to the calculation result of the central control module.

[0036] In some exemplary embodiments, the voltage loading module includes a multiplexing switch, a positive polarity amplification module, a negative polarity amplification module, a positive polarity digital-to-analog conversion module, a negative polarity digital-to-analog conversion module and a shift register; the multiplexing switch is respectively connected to the positive polarity amplification module, the negative polarity amplification module and the liquid crystal phase shifter, the positive polarity digital-to-analog conversion module is respectively connected to the positive polarity amplification module and the shift register, the negative polarity digital-to-analog conversion module is respectively connected to the negative polarity amplification module and the shift register, and the shift register is connected to the central control module.

[0037] In some exemplary embodiments, the baseband system includes a pattern matching module, a stream matching module, a modulation and demodulation module, and a codec module, wherein: the pattern matching module is configured to split different data streams into data areas to form baseband frame data; the stream matching module is configured to perform timing management, data padding, and scrambling and demodulation processing on the baseband frame data; the modulation and demodulation module is configured to modulate or demodulate the baseband frame data; and the codec module is configured to encode or decode the baseband frame data.

[0038] Still other aspects will become apparent upon reading and understanding the accompanying drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings are intended to provide a further understanding of the technical solutions of the present disclosure and constitute part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solutions of the present disclosure and do not constitute a limitation of the technical solutions of the present disclosure. The shapes and sizes of one or more components in the accompanying drawings do not reflect the actual scale and are intended only to illustrate the contents of the present disclosure.

[0040] Figure 1 A schematic flow chart of a scanning method for a phased array antenna according to an exemplary embodiment of the present disclosure;

[0041] Figure 2 A schematic flow chart of another scanning method for a phased array antenna according to an exemplary embodiment of the present disclosure;

[0042] Figure 3 A schematic flow chart of another scanning method of a phased array antenna according to an exemplary embodiment of the present disclosure;

[0043] Figure 4 A schematic flow chart of another scanning method of a phased array antenna according to an exemplary embodiment of the present disclosure;

[0044] Figure 5 This is a schematic structural diagram of a liquid crystal phase shifter according to an exemplary embodiment of the present disclosure;

[0045] Figure 6 The figure is a schematic structural diagram of an antenna system according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0046] The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. The embodiments can be implemented in a variety of different forms. A person skilled in the art can easily understand that the method and content can be transformed into one or more forms without departing from the purpose and scope of the present disclosure. Therefore, the present disclosure should not be interpreted as being limited to the contents described in the following embodiments. In the absence of conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other in any way.

[0047] In the drawings, the size of one or more components, layer thicknesses, or regions may be exaggerated for clarity. Therefore, one embodiment of the present disclosure is not necessarily limited to these dimensions, and the shapes and sizes of various components in the drawings do not reflect true proportions. Furthermore, the drawings schematically illustrate idealized examples, and one embodiment of the present disclosure is not limited to the shapes or values ​​shown in the drawings.

[0048] In the present disclosure, ordinal numbers such as "first," "second," and "third" are provided to avoid confusion among constituent elements, and are not intended to limit the number. In the present disclosure, "plurality" refers to a number of two or more.

[0049] In this disclosure, for convenience, words and phrases indicating orientation or positional relationships, such as "middle," "upper," "lower," "front," "back," "vertical," "horizontal," "top," "bottom," "inside," and "outside," are used to illustrate the positional relationships of constituent elements with reference to the accompanying drawings. This is merely for the convenience of describing this specification and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it should not be understood as a limitation of this disclosure. The positional relationships of constituent elements are appropriately changed according to the direction in which the constituent elements are described. Therefore, the words and phrases are not limited to those described in the specification and can be appropriately replaced according to the circumstances.

[0050] In this disclosure, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed, removable, or integral connections; mechanical or electrical connections; direct connections, indirect connections through intermediaries, or internal communication between two components. Those skilled in the art will understand the meaning of these terms in this disclosure based on the specific circumstances.

[0051] In this disclosure, "electrically connected" includes components connected together via an element having some electrical function. There are no particular limitations on the "element having some electrical function" as long as it enables the transfer of electrical signals between the connected components. Examples of "element having some electrical function" include not only electrodes and wiring, but also switching elements such as transistors, resistors, inductors, capacitors, and other elements having one or more functions.

[0052] In this disclosure, "parallel" refers to a state where the angle formed by two straight lines is greater than -10° and less than 10°, and thus includes a state where the angle is greater than -5° and less than 5°. Furthermore, "perpendicular" refers to a state where the angle formed by two straight lines is greater than 80° and less than 100°, and thus includes a state where the angle is greater than 85° and less than 95°.

[0053] The terms “approximately” and “substantially” in the present disclosure do not strictly define the limits and allow for errors within the range of process and measurement errors.

[0054] Phased array antennas modify the shape of their radiation patterns by controlling the feed phase of the array's radiating elements. This phase control can shift the direction of the antenna's maximum radiation pattern to achieve signal reception. Liquid crystal phased array antennas, which utilize liquid crystal deflection for phase control, have garnered significant attention in display devices.

[0055] The present disclosure provides a scanning method for a phased array antenna, wherein the phased array antenna includes a plurality of antenna elements and a liquid crystal phase shifter for performing phase calibration on the plurality of antenna elements. Figure 1 As shown, the scanning method includes:

[0056] Step 101: Apply a first wave control voltage to a liquid crystal phase shifter to detect first reception signal levels received by a plurality of antenna array elements.

[0057] Step 102: Use an artificial intelligence algorithm to continuously adjust the first wave control voltage and detect the second received signal levels received by multiple antenna array elements until the ratio of the first received signal level to the second received signal level is greater than or equal to a first threshold.

[0058] The scanning method of the phased array antenna provided in the embodiment of the present disclosure continuously adjusts the first wave control voltage by using an artificial intelligence algorithm, and combines the artificial intelligence algorithm with the antenna scanning method. It can automatically and quickly adjust the scanning angle to the optimal angle, which not only realizes intelligent scanning, but also improves the scanning speed and accuracy of the antenna.

[0059] In some exemplary embodiments, the first threshold is between 0.841 and 0.944, which ensures that the power value difference between the received signal before adjustment and the received signal after adjustment is between 0.5 dB and 1.5 dB.

[0060] Optionally, the first threshold may be 0.891.

[0061] This embodiment uses an artificial intelligence algorithm to fine-tune the antenna's scanning angle. Generally speaking, the beam pointing during fine-tuning is required to meet 1dB bandwidth accuracy, that is, to ensure that the power difference between the received signal before and after adjustment is less than 1dB. Based on the relationship between signal power and signal level, the ratio of the received signal level value before adjustment to the received signal level value after adjustment must be greater than or equal to 0.891. That is, the first threshold value can be 0.891.

[0062] In some exemplary embodiments, the artificial intelligence algorithm may be a genetic algorithm or a particle swarm optimization algorithm.

[0063] The genetic algorithm (GA) described in this disclosure is a computational model of biological evolution that simulates the natural selection and genetic mechanisms of Darwin's theory of evolution. It is a method for searching for optimal solutions by simulating natural evolutionary processes. The GA uses all individuals in a population as its target and utilizes randomization techniques to guide an efficient search through an encoded parameter space.

[0064] The particle swarm optimization (PSO) algorithm described in the present disclosure is a random search algorithm based on group collaboration developed by simulating the foraging behavior of bird flocks.

[0065] In some exemplary embodiments, the received signals of the embodiments of the present disclosure (including the first received signal, the second received signal, and the third to sixth received signals described below) may be pilot signals.

[0066] In this embodiment, the satellite signal includes a data signal and a pilot signal. The pilot signal refers to a signal sent for measurement or monitoring purposes. Generally speaking, the power of the pilot signal is greater than that of the data signal, and the modulation method is simpler, making it easier to decode.

[0067] In some exemplary embodiments, the scanning method further includes:

[0068] Dividing the area to be scanned of the phased array antenna into a plurality of first sub-areas, adjusting the wave control voltage of the liquid crystal phase shifter to detect the level values ​​of the third received signal received in the plurality of first sub-areas, and determining the first sub-area corresponding to the maximum third received signal level value;

[0069] A first subregion corresponding to the maximum third received signal level value is divided into multiple second subregions, and a wave control voltage of the liquid crystal phase shifter is adjusted to detect the received fourth received signal level values ​​in the multiple second subregions. When the ratio of the maximum third received signal level value to the maximum fourth received signal level value is less than a second threshold, the maximum fourth received signal level value is updated to the maximum third received signal level value, the second subregion corresponding to the maximum fourth received signal level value is updated to the first subregion corresponding to the maximum third received signal level value, and an operation of dividing the first subregion corresponding to the maximum third received signal level value into multiple second subregions is triggered until the ratio of the maximum third received signal level value to the maximum fourth received signal level value is greater than or equal to the second threshold.

[0070] The scanning method of the disclosed embodiment divides the area to be scanned of the phased array antenna into multiple first sub-areas, then divides the first sub-area corresponding to the maximum received signal level value into multiple second sub-areas, and repeatedly divides the second sub-areas until the received signal level meets a preset threshold condition, thereby continuously refining the selected area of ​​the first sub-area. This implements a fast scanning method based on spatial regions without requiring any prior information. Since the liquid crystal phased array antenna is an active phase-scanning antenna, switching between different directional beams only requires sub-ms time, and the front and rear beams are independent of each other, ensuring the effective implementation of the scanning method.

[0071] In some exemplary embodiments, the area to be scanned by the phased array antenna may be divided into N1 first sub-areas, where N1 may be a natural number greater than or equal to 2. Optionally, N1 is greater than or equal to 4.

[0072] In some exemplary embodiments, the first sub-region corresponding to the maximum third received signal level value is divided into N2 second sub-regions, where N2 may be a natural number greater than or equal to 2. Optionally, N2 is greater than or equal to 4. N2 may be equal to or different from N1, and this disclosure is not limited thereto.

[0073] In some exemplary embodiments, the area to be scanned by the phased array antenna is divided into a plurality of first sub-areas, specifically: the area to be scanned by the phased array antenna is evenly divided into the plurality of first sub-areas along the vertical direction.

[0074] In some exemplary embodiments, the first sub-region corresponding to the maximum third received signal level value is divided into multiple second sub-regions, specifically: the area to be scanned of the phased array antenna is evenly divided into multiple first sub-regions along the vertical direction.

[0075] In this embodiment, the method for dividing the first sub-region and the method for dividing the second sub-region may be the same or different. For example, in order to reduce complexity, the same method may be selected for the two divisions.

[0076] In some exemplary embodiments, the second threshold is between 0.631 and 0.841, which ensures that the power value difference between the received signal before adjustment and the received signal after adjustment is between 1.5 dB and 4 dB.

[0077] Exemplarily, the second threshold may be 0.707.

[0078] In this embodiment, when initializing the scanning of the phased array antenna, the beam pointing is generally required to meet a 3dB bandwidth accuracy. According to the relationship between signal power and signal level, it is necessary to ensure that the ratio of the level value of the received signal before adjustment to the level value of the received signal after adjustment is greater than or equal to 0.707, that is, the second threshold value can be 0.707.

[0079] In some exemplary embodiments, Figure 2 As shown, an embodiment of the present disclosure provides an antenna scanning method, comprising the following steps:

[0080] 1. Within the entire antenna viewing angle (scanning range), the area to be scanned is divided into N1 (N1 ≥ 4) first sub-areas. Based on the relationship between the beam control voltage and the beam pointing direction, N1 groups of initial beam control voltages are set to ensure that the beam corresponding to each group of initial beam control voltages points to one of the divided first sub-areas.

[0081] 2. After the antenna system is powered on, the N1 first sub-areas are scanned one by one according to the set N1 group initial wave control voltage. When scanning the first first sub-area, the amplitude level value V1 and the area number 1 of the detected pilot signal are recorded. When scanning the second first sub-area, the amplitude level value V2 of the detected pilot signal is recorded and compared with V2 and V1. If V2>V1, V1 is replaced by V2, and the area number is recorded as 2. Otherwise, V1 and area number 1 are kept unchanged. This process is repeated until all N1 first sub-areas are scanned and the maximum amplitude level value V of the recorded pilot signal is obtained. N and the area number N corresponding to the corresponding first sub-area;

[0082] 3. Divide the first sub-region corresponding to region number N into N2 second sub-regions, then set N2 groups of wave control voltages to ensure that the beam corresponding to each group of wave control voltages points to a divided second sub-region. According to the above method, find the second sub-region N' with the maximum amplitude level value of the detected pilot signal, and record the new maximum level V N‘ ;

[0083] 4. Compare V N With V N’ If V N / V N’ <0.707, then update the second sub-region N' with the largest amplitude level value of the detected pilot signal to the first sub-region corresponding to region number N, and repeat step 3 until the ratio of the two level values ​​is greater than or equal to 0.707 (that is, the power value difference is less than 3 dB);

[0084] 5. Based on the driving voltage V in step 4 Ni’ , fine-tune the phase shift of each channel (obtain the corresponding driving voltage according to the voltage-phase shift curve of the liquid crystal phase shifter). Fine-tuning can be done using artificial intelligence based genetic algorithm or particle swarm optimization algorithm until the ratio of the two level values ​​is greater than or equal to 0.891 (that is, the power value difference is less than 1dB).

[0085] In some exemplary embodiments, the scanning method further includes:

[0086] Calculate the satellite's rough position based on the phased array antenna's position information and pre-installed satellite ephemeris information, and receive satellite broadcast ephemeris based on the calculated satellite's rough position;

[0087] When receiving satellite broadcast ephemeris, calculate the precise position of the satellite based on the received satellite broadcast ephemeris;

[0088] When no satellite broadcast ephemeris is received, the current wave control voltage is recorded as the aforementioned first wave control voltage, and the current received signal level value is recorded as the aforementioned first received signal level value, triggering the aforementioned operation of continuously adjusting the first wave control voltage using an artificial intelligence algorithm.

[0089] Although the beam pointing of the liquid crystal phased array antenna is only related to the driving voltage, which ensures the timeliness of the fast scanning method based on the spatial area, "blind scanning" will still take up a certain amount of startup time. Therefore, the embodiment of the present disclosure also provides another feasible star-seeking strategy based on the liquid crystal phased array antenna, namely, a program-controlled scanning method based on satellite ephemeris. Satellite ephemeris is an expression used to describe the position and velocity of a space flight object, also known as two-line orbital data (Two-Line Orbital Element, TLE). The main parameters include satellite number, orbit eccentricity, reference time, orbit inclination, rate of change of ascending node right ascension, square root of the major axis of the orbit, ascending node right ascension, perigee depression angle, mean anomaly angle, clock correction parameters, etc., which can accurately calculate, predict, depict, and track the time, position, velocity and other operating states of satellites and flight objects. The embodiment of the present disclosure does not elaborate on how to use ephemeris to calculate position, velocity, etc.

[0090] In some exemplary embodiments, calculating a satellite coarse position based on the phased array antenna's position information and pre-installed satellite ephemeris information, and receiving satellite broadcast ephemeris based on the calculated satellite coarse position includes:

[0091] Obtaining position information and attitude information of the phased array antenna (for example, the position information of the phased array antenna can be obtained based on the GPS positioning module, and the attitude information of the phased array antenna can be obtained based on the gyroscope module);

[0092] Calculate the satellite's rough position based on the acquired position information and attitude information as well as pre-installed satellite ephemeris information;

[0093] Calculate the azimuth and elevation angle information between the phased array antenna and the satellite based on the calculated rough satellite position;

[0094] Satellite capture and satellite broadcast ephemeris reception are performed based on the calculated azimuth and elevation angle information and the preset antenna scanning angle and wave control voltage lookup table.

[0095] In some exemplary embodiments, Figure 3 As shown, an embodiment of the present disclosure provides an antenna scanning method, comprising the following steps:

[0096] 1.According to the GPS positioning module, obtain the location information of the liquid crystal phased array antenna;

[0097] 2. Obtain the attitude information of the liquid crystal phased array antenna based on the gyroscope module;

[0098] 3. Based on the basic orbital parameters provided by the pre-installed almanac of the liquid crystal phased array antenna, low-precision satellite position information is quickly calculated in the baseband system;

[0099] 4. Perform coordinate system conversion on the posture and orientation information from steps 1 to 3, unify them into one coordinate system, and obtain the azimuth and elevation angle information of the antenna and satellite;

[0100] 5. Rapid satellite capture is performed based on the scanning angle-wave control voltage lookup table of the liquid crystal phase shifter and the azimuth and elevation angle information obtained in step 4;

[0101] 6. Receive low-bit-rate satellite broadcast ephemeris, calculate the precise position of the satellite in the baseband system, and repeat steps 4 to 5 to obtain the maximum amplitude level V after precise pointing. max ;

[0102] 7. If the satellite broadcast ephemeris is not received, the phase shift amount of each channel is fine-tuned based on the wave control voltage in step 5 (the corresponding wave control voltage is obtained according to the wave control voltage-phase shift amount curve of the liquid crystal phase shifter). Fine-tuning can be done using artificial intelligence based genetic algorithm or particle swarm optimization algorithm until the ratio of the two level values ​​is greater than or equal to 0.891 (that is, the power value difference is less than 1dB).

[0103] The above two scanning methods (the rapid scanning method based on spatial areas and the program-controlled scanning method based on satellite ephemeris) are both for initial satellite search and initial connection establishment. When the established information connection is interrupted due to reasons such as tunnel signal obstruction, large-angle steering, etc., the phased array antenna needs to be able to quickly align with the satellite and restore the connection. At this time, the inertial navigation module can be used for azimuth correction, and then the adaptive algorithm can be used for precise positioning.

[0104] In some exemplary embodiments, when the connection between the phased array antenna and the satellite is interrupted, the scanning method further includes:

[0105] Record the received signal level value before the connection is interrupted as the fifth received signal level value, and record the current received signal level value as the sixth received signal level value;

[0106] When the ratio of the sixth received signal level value to the fifth received signal level value is less than the third threshold, the beam pointing of the phased array antenna is adjusted according to the inertial navigation acceleration information, and the adjusted beam control voltage is recorded as the first beam control voltage, triggering the operation of continuously adjusting the first beam control voltage using an artificial intelligence algorithm.

[0107] In this embodiment, since a stable connection is established in advance, the fifth received signal and the sixth received signal can be pilot signals or data signals. Optionally, for simplicity, the fifth received signal and the sixth received signal are both pilot signals.

[0108] In some exemplary embodiments, the third threshold is between 0.707 and 0.891, that is, the power value difference between the sixth received signal and the fifth received signal is less than 1 dB to 3 dB.

[0109] Exemplarily, the third threshold may be 0.891 (ie, the power value difference is less than 1 dB).

[0110] In some exemplary embodiments, adjusting the beam pointing of the phased array antenna according to inertial navigation acceleration information includes:

[0111] Integrate the inertial navigation acceleration over time and convert the integral result to the navigation coordinate system to obtain angle information;

[0112] Calculate the correction angle of the phased array antenna according to the angle information, and convert the correction angle into a normal deflection angle;

[0113] Adjust the beam pointing of the phased array antenna according to the normal deflection angle, the preset antenna scanning angle and the beam control voltage lookup table.

[0114] like Figure 4 As shown, the embodiment of the present disclosure also provides an inertial navigation adaptive scanning method, including the following steps:

[0115] 1. Record the signal level value V for establishing a stable connection s ;

[0116] 2. Determine the current signal level V t With V s Relationship, if V t / V s <0.891, record inertial navigation acceleration information;

[0117] 3. Integrate the acceleration over time and convert the integral result into the navigation coordinate system to obtain angle information;

[0118] 4. Based on the angle information, calculate the correction angle of the liquid crystal phased array antenna and convert it to the normal deflection angle;

[0119] 5. According to the liquid crystal phase shifter scanning angle-wave control voltage lookup table, adjust the beam pointing and record the level value V r ;

[0120] 6. Based on the driving voltage V in step 5 r , fine-tune the phase shift of each channel (obtain the corresponding driving voltage according to the voltage-phase shift curve of the liquid crystal phase shifter). Fine-tuning can be done using artificial intelligence based genetic algorithm or particle swarm optimization algorithm until the ratio of the two level values ​​is greater than or equal to 0.891 (that is, the power value difference is less than 1dB).

[0121] The antenna scanning method of the disclosed embodiment adds an inertial navigation module, which can record the position and azimuth changes of the antenna in real time, allowing the antenna to make a quick correction response to avoid losing and re-capturing the satellite.

[0122] An embodiment of the present disclosure further provides a phased array antenna, comprising: a plurality of antenna elements and a liquid crystal phase shifter for performing phase calibration on the plurality of antenna elements, wherein the phased array antenna is scanned using the scanning method as described in any of the preceding items.

[0123] Liquid crystal phased array antennas use liquid crystal phase shifters based on the adjustable dielectric constant of liquid crystal as phase shift units, which have the advantages of low cost, low surface area, and easy conformality. A typical liquid crystal phase shifter structure is as follows: Figure 5 As shown, the mainstream technical solutions for liquid crystal phase shifters include microstrip transmission lines, coplanar waveguide transmission lines, periodic variable capacitors, etc. The essence of achieving phase shifting is to form an electric field by applying a driving voltage. Under the action of the electric field force, the liquid crystal molecules are flipped, resulting in a change in the dielectric constant, which in turn changes the transmission speed of the electromagnetic wave and produces a phase difference under the conditions of the same length transmission line.

[0124] The present disclosure also provides an antenna system, including a baseband system, an antenna feed system, and a beam control system, wherein:

[0125] The baseband system is configured to perform baseband processing on the signal;

[0126] The antenna feed system is configured to transmit and receive satellite signals; the antenna feed system includes a phased array antenna, a combiner, a power splitter, a downconverter, and an upconverter; the phased array antenna includes: a plurality of antenna elements and a liquid crystal phase shifter for phase calibration of the plurality of antenna elements; the combiner is connected to the downconverter, and the power splitter is connected to the upconverter;

[0127] The wave control system is configured to drive and control the liquid crystal phase shifter. The wave control system includes a central control module, an inertial navigation module, a positioning module and an attitude detection module. The central control module controls the phased array antenna to scan using any of the scanning methods described above.

[0128] In the embodiment of the present disclosure, Figure 6As shown in FIG, the antenna system mainly includes an antenna feed system, a beam control system and a digital baseband system. The antenna feed system is responsible for receiving and transmitting electromagnetic waves in the satellite communication frequency band, feeding and outputting guided waves, and signal preprocessing. It mainly consists of an antenna cover, a transceiver antenna array, a slot coupling structure, a liquid crystal phase shifter, a buffer foam (because the liquid crystal phase shifter is glass-based, foam is used for buffering and fixing to avoid unevenness and stress), a microstrip to waveguide structure, a waveguide power splitter / combiner, a wave-to-coaxial conversion structure (a structure in which the waveguide is converted into an RF coaxial connector, which can be subsequently transmitted using an RF coaxial cable), an RF connector, an RF cable, a high-frequency head (LNB) and a block converter (BUC). The beam control system is responsible for driving the liquid crystal phase shifter to achieve beam pointing control. It mainly consists of an inertial navigation module, a positioning module, an attitude detection module, a central control module (the central control module can be a processor, which determines the driving voltage application strategy based on the information input by the inertial navigation in conjunction with the lookup table) and a voltage loading module. The voltage loading module can be a liquid crystal display (LCD). Display, LCD) driver chip, Figure 6 The multiplexing switch, positive / negative polarity amplification, positive / negative polarity digital-to-analog conversion, and shift register in the LCD driver chip are the internal circuit block diagram; the digital baseband system is responsible for signal mode adaptation, encoding and decoding, and modulation and demodulation, and is mainly composed of analog-to-digital (ADA) converters, field programmable gate arrays (FPGAs), digital signal processors (DSPs), and microprocessors (Advanced RISC Machines, ARMs). The overall system block diagram is shown in the figure. Figure 6 As shown ( Figure 6 It only reflects the main framework, not the details). Figure 6 The inertial navigation solution module, ephemeris solution module, and attitude and state determination module belong to the beam control system and all require a processor, but they are not part of the baseband system, which primarily uses processors to perform algorithms. Therefore, although these functions belong to different systems, in hardware implementation, they may be implemented on a single processor chip. Of course, in some exemplary embodiments, they can also be processed separately by multiple processors, which is not a limitation of this disclosure.

[0129] In some exemplary embodiments, the voltage loading module includes a multiplexing switch, a positive polarity amplification module, a negative polarity amplification module, a positive polarity digital-to-analog conversion module, a negative polarity digital-to-analog conversion module, and a shift register.

[0130] Among them, the multiplexing switch is respectively connected to the positive polarity amplification module, the negative polarity amplification module and the liquid crystal phase shifter, the positive polarity digital-to-analog conversion module is respectively connected to the positive polarity amplification module and the shift register, the negative polarity digital-to-analog conversion module is respectively connected to the negative polarity amplification module and the shift register, and the shift register is connected to the central control module.

[0131] The working process of the liquid crystal phased array antenna system is briefly described as follows: For the receive link, the receive antenna array receives satellite signals in the desired azimuth space. These signals are fed through a feed structure into a liquid crystal phase shifter for phase compensation (the phase shifter's drive signal is determined by the inertial navigation module and the target satellite's beam direction, provided by the LCD driver chip). The signals then pass through the feed structure into a combiner for energy superposition. A high-frequency head performs down-conversion, preliminary amplification, and filtering, and outputs an intermediate frequency (IF) signal to an analog-to-digital converter (ADC) for quantization. The quantized digital signal undergoes a series of matching processes (such as pattern matching and stream matching) in the baseband processor, followed by demodulation and decoding, before being converted into user-usable data. For the transmit link, the process is essentially the opposite of the receive link. User data first undergoes baseband encoding, modulation, and waveform shaping, then is converted to an analog IF signal by a digital-to-analog converter (DAC). A block converter then performs up-conversion and amplification, and after passing through a power divider, it is fed into a liquid crystal phase shifter for phase adjustment. Finally, the transmit antenna array radiates the signal.

[0132] In the disclosed embodiment, pattern matching is to split different data streams into data areas, and after pattern matching, baseband frame data is formed, which mainly includes normal mode NM (Normal Mode) and high-efficiency mode HEM (High Efficiency Mode); stream matching is to perform timing management, data filling, and scrambling and descrambling processing on baseband frame data, mainly including TS (Transport Stream), GSE (Generic Encapsulated Stream), GCS (Generic Continuous Stream), GFPS (Generic Fixed-length Packetized Stream), etc.

[0133] In the disclosed embodiments, since the coding and modulation methods of satellite communication systems are simpler than those of mobile communication systems, the baseband system can be implemented in a variety of ways, including: FPGA+ARM, FPGA+DSP, FPGA+ARM+DSP, and FPGA integrated with PS (Processing System) and PL (Programmable Logic).

[0134] In the disclosed embodiment, the hardware implementation of the beam control system includes a gyroscope module, a positioning module, an inertial navigation module, and a voltage loading module (the voltage loading module includes an LCD driver chip and peripheral circuits and wiring). In order to obtain accurate antenna attitude information, the gyroscope module can select a micromechanical gyroscope, a ring laser gyroscope, and a fiber optic gyroscope. The positioning module can obtain the position information of the antenna, and a GPS (Global Positioning System) positioning module, a Beidou (BD) positioning module, and a Galileo (Galileo) positioning module can be selected. The inertial navigation module mainly uses the current position and gyroscope information to predict the future position, and is used to quickly recover after the signal is interrupted due to obstruction or other reasons. A strapdown inertial navigation and a platform inertial navigation can be used; the voltage loading module mainly drives the liquid crystal phase shifter according to the scanning algorithm to achieve beam control, which can be driven by a combination of an analog-to-digital converter and an operational amplifier or by designing a dedicated chip.

[0135] The drawings in this disclosure only relate to the structures involved in this disclosure, and other structures may refer to general designs. In the absence of conflict, the embodiments of this disclosure and the features in the embodiments may be combined with each other to obtain new embodiments.

[0136] It should be understood by those skilled in the art that the technical solutions of the present disclosure may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present disclosure, and all should be included in the scope of the claims of the present disclosure.

Claims

1. A scanning method for a phased array antenna, the phased array antenna comprising a plurality of antenna elements and a liquid crystal phase shifter for performing phase calibration on the plurality of antenna elements, the scanning method comprising: Applying a first wave control voltage to the liquid crystal phase shifter to detect first reception signal level values ​​received by the plurality of antenna array elements; An artificial intelligence algorithm is used to continuously adjust the first wave control voltage and detect the second received signal level values ​​received by the multiple antenna array elements until the ratio of the first received signal level value to the second received signal level value is greater than or equal to a first threshold.

2. The scanning method according to claim 1, further comprising: Dividing the to-be-scanned area of ​​the phased array antenna into a plurality of first sub-areas, adjusting the wave control voltage of the liquid crystal phase shifter to detect third received signal level values ​​received in the plurality of first sub-areas, and determining the first sub-area corresponding to the maximum third received signal level value; A first subregion corresponding to the maximum third received signal level value is divided into multiple second subregions, and a wave control voltage of the liquid crystal phase shifter is adjusted to detect the received fourth received signal level values ​​in the multiple second subregions. When the ratio of the maximum third received signal level value to the maximum fourth received signal level value is less than a second threshold, the maximum fourth received signal level value is updated to the maximum third received signal level value, the second subregion corresponding to the maximum fourth received signal level value is updated to the first subregion corresponding to the maximum third received signal level value, and an operation of dividing the first subregion corresponding to the maximum third received signal level value into multiple second subregions is triggered until the ratio of the maximum third received signal level value to the maximum fourth received signal level value is greater than or equal to the second threshold.

3. The scanning method according to claim 2, wherein: The dividing the area to be scanned by the phased array antenna into a plurality of first sub-areas includes: evenly dividing the area to be scanned by the phased array antenna into a plurality of first sub-areas along a vertical direction; The dividing the first sub-region corresponding to the maximum third received signal level value into a plurality of second sub-regions specifically includes: evenly dividing the area to be scanned by the phased array antenna into a plurality of first sub-regions along a vertical direction.

4. The scanning method according to claim 2, wherein: The second threshold is between 0.631 and 0.

841.

5. The scanning method according to claim 1, wherein: The first threshold is between 0.841 and 0.

944. The scanning method according to claim 1 , wherein: The artificial intelligence algorithm is a genetic algorithm or a particle swarm optimization algorithm.

7. The scanning method according to claim 1, wherein: The first received signal is a pilot signal, and the second received signal is a pilot signal.

8. The scanning method according to claim 1, further comprising: Calculating a rough satellite position based on the position information of the phased array antenna and pre-installed satellite ephemeris information, and receiving satellite broadcast ephemeris based on the calculated rough satellite position; When receiving satellite broadcast ephemeris, calculate the precise position of the satellite based on the received satellite broadcast ephemeris; When no satellite broadcast ephemeris is received, the current wave control voltage is recorded as the first wave control voltage, and the current received signal level value is recorded as the first received signal level value, triggering the operation of continuously adjusting the first wave control voltage using the artificial intelligence algorithm.

9. The scanning method according to claim 8, wherein: The calculating the satellite coarse orientation according to the posture information of the phased array antenna and the pre-installed satellite ephemeris information, and receiving the satellite broadcast ephemeris according to the calculated satellite coarse orientation, includes: Acquiring position information and attitude information of the phased array antenna; Calculate the satellite's rough position based on the acquired position information and attitude information as well as pre-installed satellite ephemeris information; Calculating azimuth and elevation angle information of the phased array antenna and the satellite based on the calculated rough satellite position; Satellite capture and satellite broadcast ephemeris reception are performed based on the calculated azimuth and elevation angle information and a preset antenna scanning angle and wave control voltage lookup table.

10. The scanning method according to claim 1, wherein when the connection between the phased array antenna and the satellite is interrupted, the scanning method further comprises: Record the received signal level value before the connection is interrupted as the fifth received signal level value, and record the current received signal level value as the sixth received signal level value; When the ratio of the sixth received signal level value to the fifth received signal level value is less than a third threshold, the beam pointing of the phased array antenna is adjusted according to the inertial navigation acceleration information, and the adjusted beam control voltage is recorded as the first beam control voltage, triggering the operation of continuously adjusting the first beam control voltage using the artificial intelligence algorithm. The scanning method according to claim 10 , wherein: The third threshold is between 0.707 and 0.

891.

12. The scanning method according to claim 10, wherein: The adjusting the beam pointing of the phased array antenna according to the inertial navigation acceleration information includes: Performing time integration on the inertial navigation acceleration and converting the integration result into a navigation coordinate system to obtain angle information; Calculating a correction angle of the phased array antenna according to the angle information, and converting the correction angle into a normal deflection angle; The beam pointing direction of the phased array antenna is adjusted according to the normal deflection angle and a preset antenna scanning angle and beam control voltage lookup table.

13. The scanning method according to claim 10, wherein: The fifth received signal is a pilot signal or a data signal, and the sixth received signal is a pilot signal or a data signal.

14. A phased array antenna, comprising: A plurality of antenna array elements and a liquid crystal phase shifter for performing phase calibration on the plurality of antenna array elements, wherein the phased array antenna is scanned using the scanning method according to any one of claims 1 to 13.

15. The phased array antenna according to claim 14, wherein: The liquid crystal phase shifter includes any one or more of the following: a microstrip transmission line, a coplanar waveguide transmission line, and a periodic variable capacitor.

16. An antenna system comprising: Baseband system, antenna feed system and beam control system, including: The baseband system is configured to perform baseband processing on the signal; The antenna feed system is configured to transmit and receive satellite signals; the antenna feed system includes a phased array antenna, a combiner, a power splitter, a downconverter, and an upconverter, the phased array antenna including: a plurality of antenna elements and a liquid crystal phase shifter for performing phase calibration on the plurality of antenna elements, the combiner is connected to the downconverter, and the power splitter is connected to the upconverter; The wave control system is configured to drive and control the liquid crystal phase shifter. The wave control system includes a central control module, a voltage loading module, an inertial navigation module, a positioning module, and a posture detection module. The central control module is configured to receive data from the inertial navigation module, the positioning module, and the posture detection module, and calculate the wave control voltage required by the liquid crystal phase shifter to control the phased array antenna to scan according to the scanning method according to any one of claims 1 to 13; the voltage loading module is configured to output a corresponding wave control voltage to the liquid crystal phase shifter according to the calculation result of the central control module.

17. The antenna system according to claim 16, wherein: The voltage loading module includes a multiplexing switch, a positive polarity amplification module, a negative polarity amplification module, a positive polarity digital-to-analog conversion module, a negative polarity digital-to-analog conversion module and a shift register; The multiplexing switch is respectively connected to the positive polarity amplification module, the negative polarity amplification module and the liquid crystal phase shifter, the positive polarity digital-to-analog conversion module is respectively connected to the positive polarity amplification module and the shift register, the negative polarity digital-to-analog conversion module is respectively connected to the negative polarity amplification module and the shift register, and the shift register is connected to the central control module.

18. The antenna system according to claim 16, wherein: The baseband system includes a pattern matching module, a stream matching module, a modulation and demodulation module and a coding and decoding module; The pattern matching module is configured to split different data streams into data areas to form baseband frame data; The stream matching module is configured to perform timing management, data padding, and scrambling and descrambling processing on the baseband frame data; The modulation and demodulation module is configured to perform modulation or demodulation processing on the baseband frame data; The encoding and decoding module is configured to perform encoding or decoding processing on the baseband frame data.

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