Active phased-array antenna device with built-in calibration network and calibration method

Abstract

The invention relates to the technical field of active phased-array antennas, in particular to an active phased-array antenna device with a built-in calibration network and a calibration method, and the method comprises the steps: carrying out the initialization configuration of a phased-array antenna, and setting the working state of the phased-array antenna; according to the set working state, the main control unit is used for judging whether re-calibration is needed or not; if it is judged that re-calibration is needed, the main control unit sends out a calibration instruction to start a calibration program, the amplitude and phase control unit is controlled through the calibration program to conduct calibration, and a corresponding two-dimensional standard table is generated and stored in a database storage unit; if it is judged that re-calibration is not needed, an existing two-dimensional standard table is obtained from a database storage unit; the current working frequency is obtained, and the attenuator value and the phase shifter value of each channel are configured according to the obtained two-dimensional calibration table, so that each channel of the phased-array antenna is calibrated, and the self calibration of the amplitude and the phase of the active phased-array antenna can be carried out at any time in the whole service life period.

Description

Technical Field

[0001] The present invention relates to the technical field of active phased array antennas, and more specifically, to an active phased array antenna device with a built-in calibration network and a calibration method. Background Art

[0002] Although the active phased array antenna adopts a symmetrical structure and the same link design when designing each channel link, due to structural errors and differences in active device characteristics, processing accuracy, operating frequency, and ambient temperature, the amplitude and phase of each channel are quite different. Therefore, the active phased array antenna must be calibrated for amplitude and phase before leaving the factory to ensure the consistency of the initial amplitude and phase of each channel, so as to improve the key indicators of the phased array such as beam pointing accuracy and side lobes. In the prior art, active phased array antennas are usually calibrated by mutual coupling calibration or with the help of external microwave darkroom auxiliary antenna conditions. This method requires an expensive microwave darkroom test environment and a precise servo control drive measurement probe. The device is also complex and costly. In addition, since active array antennas are used on devices with a long service life, internal conditions may change significantly during their life cycle due to factors such as device aging, environmental impacts, and consistency of temperature and humidity responses of active components. Therefore, the calibration of active array antennas before leaving the factory cannot guarantee the amplitude and phase consistency of the array throughout its life cycle. In the application field of millimeter-wave phased arrays, due to the small size and high integration of the products, the up and down frequency conversion parts are usually combined with the antenna array surface, which brings greater difficulty to the amplitude and phase calibration of phased array antennas.

[0003] Therefore, in order to solve the above problems, the present application provides an active phased array antenna with a built-in calibration network that can realize its own calibration function to solve the above problems and ensure the stable and reliable operation of the entire device throughout its life cycle. Summary of the invention

[0004] The present invention aims to overcome at least one defect (shortcoming) of the above-mentioned prior art and provide an active phased array antenna device and a calibration method with a built-in calibration network, so as to solve the problems that the existing active phased array antenna can not guarantee the consistency of the array amplitude and phase during the entire life cycle only by relying on the calibration of the active array antenna before leaving the factory, and the existing calibration method is highly complex and expensive.

[0005] The technical solution adopted by the present invention is an active phased array antenna device with a built-in calibration network, the device comprising: a transmitting link, a receiving link, a calibration link and a main control unit; wherein the main control unit is respectively connected to the transmitting link, the receiving link and the calibration link, and is used to control the reception and transmission of signals and control the amplitude and phase calibration of each channel;

[0006] In the calibration link, a double-balanced passive mixer, a bandpass filter, a bidirectional power amplifier and a calibration feed network are bidirectionally connected in sequence, and the calibration feed network is connected to the couplers of the transmitting link and the receiving link in a bidirectional connection manner to realize bidirectional transmission of signals in the calibration link;

[0007] The device also includes an amplitude and phase control unit and a vector network analyzer. The vector network analyzer is used to connect the transmission link and the calibration link or to connect the receiving link and the calibration link. When calibrating the transmission link or the receiving link, the amplitude and phase response of each channel is accurately measured, and the measurement results are fed back to the main control unit. The main control unit generates corresponding instructions based on the results to control the amplitude and phase control unit to perform amplitude and phase calibration on each channel.

[0008] In the active phased array antenna device, the up and down frequency conversion part is combined with the antenna array surface, which contains multiple antenna units. The signal of each unit must be synchronized at the correct amplitude and phase to achieve electronic scanning and direction control of the beam. Therefore, it is particularly important to calibrate the amplitude and phase of each channel of the antenna array surface. In the present application, a calibration link capable of bidirectional signal transmission is set in the device, so that both the transmitting link and the receiving link can be calibrated through the calibration link, and the amplitude and phase control unit is combined to enable the active phased array antenna to correct the amplitude and phase deviations of each channel at any time during use, thereby avoiding the problems of amplitude and phase inconsistency in each channel of the active phased array antenna caused by manufacturing tolerances, aging, environmental changes, etc., and the vector network analyzer is combined with the calibration link to detect the deviation in real time and calibrate and compensate in time, thereby eliminating the performance degradation caused by these inconsistencies. Problems such as improved overall accuracy of the device, ensure the accuracy of the transmitting and receiving beams, and ensure the reliability of the active phased array antenna device.

[0009] Preferably, the transmitting link and the receiving link further include several T / R components, and the T / R components include a radio frequency switch, a T attenuator, a T phase shifter, a power amplifier, an R attenuator, an R phase shifter, a low noise amplifier and a radio frequency switch;

[0010] The amplitude and phase control unit is respectively connected to the T attenuator, T phase shifter, R attenuator, and R phase shifter on each T / R component. When calibrating the transmission link, the amplitude and phase control unit calibrates the channel by adjusting the T attenuator and T phase shifter; when calibrating the receiving link, the amplitude and phase control unit calibrates the channel by adjusting the R attenuator and R phase shifter.

[0011] In the present invention, an amplitude and phase control unit is used to adjust the phase shifter and attenuator, so as to obtain the calibration values ​​of the attenuator and phase shifter of the corresponding channel, which simplifies the calibration process and ensures that the amplitude and phase adjustment of all channels in the device are relative to the same reference, thereby reducing complexity and potential errors, helping to maintain the response consistency between the channels of the active phased array antenna, and improving the performance and stability of the antenna array.

[0012] Preferably, the transmitting link and the receiving link also include an intermediate frequency amplifier, a mixer, a bandpass filter, a power amplifier, a radio frequency switch, a power division network and an antenna unit;

[0013] Among them, in the transmission link, the signal is first amplified by the intermediate frequency amplifier and then input into the mixer, up-converted to the radio frequency frequency by the mixer, and then filtered out the local oscillator signal and other mixing signals by the bandpass filter. After amplification by the power amplifier, the radio frequency switch is turned on to the transmission link, so that the power division network is connected to the power amplifier. The power division network divides the signal amplified by the power amplifier into several channel signals and enters the corresponding T / R components for processing, and finally radiates out through the antenna unit after passing through the coupler;

[0014] In the receiving link, after the antenna unit receives the signal, it is input into the corresponding T / R component for processing after passing through the coupler, and then the power division network is used to converge multiple signals into a single port for signal synthesis. The RF switch is turned on to the receiving link so that the synthesized signal is processed in turn through the power amplifier, bandpass filter, mixer and intermediate frequency amplifier to obtain the received signal.

[0015] In the present application, before transmitting a signal through an antenna or receiving a signal through an antenna, a coupler is required to couple the signal. If the channel needs to be calibrated, the coupled signal of each channel enters the calibration link through a wire for calibration. In the calibration link, the calibration feed network can realize the combining or branching of the coupled signal, so that both the transmitting link and the receiving link can use the built-in calibration link in the device for calibration processing, without the need to calibrate each channel separately, effectively simplifying the calibration process of each channel in the active phased antenna system.

[0016] Preferably, the device also includes a frequency generator for generating a local oscillator signal, and is connected to the mixers in the transmitting link and the receiving link respectively through a power divider using a radio frequency switch, and is connected to the double-balanced passive mixer in the calibration link, so as to send the local oscillator signal to the transmitting link, the receiving link and the calibration link; when the device works in the transmitting link, the radio frequency switch is turned on to the transmitting mixer, and when the device works in the receiving link, the radio frequency switch is turned on to the receiving mixer.

[0017] In the present application, a frequency generator is provided to provide accurate frequency signals for the transmission link, the reception link and the calibration link, and the signal is input into a mixer for mixing to drive the link in the antenna array to generate the required RF signal.

[0018] Preferably, the device further comprises a database storage unit for storing amplitude and phase calibration data generated during calibration, so that when calibration is performed, the calibration data stored in the database storage unit can be directly read for calibration.

[0019] Preferably, the device also includes a radio frequency switch control unit, which is used to receive and control the radio frequency switch in the device according to the instructions of the main control unit to realize the conduction of the corresponding link, so that the device can switch between different signal paths and block the signals of unselected channels to avoid signal interference.

[0020] On the other hand, the present invention also provides an active phased array antenna calibration method based on the built-in calibration network of the above-mentioned device, and the calibration method comprises:

[0021] S1: Initialize the configuration of the phased array antenna and set its working state;

[0022] S2: Based on the set working status, the main control unit is used to determine whether recalibration is required;

[0023] S3: If it is determined that recalibration is required, the main control unit issues a calibration instruction to start the calibration program, controls the amplitude and phase control unit to perform calibration through the calibration program, generates a corresponding two-dimensional standard table and stores it in the database storage unit; if it is determined that recalibration is not required, obtains the existing two-dimensional standard table from the database storage unit;

[0024] S4: Acquire the current operating frequency and configure the attenuator value and phase shifter value of each channel according to the two-dimensional calibration table obtained in step S3, so as to calibrate each channel of the phased array antenna.

[0025] The present invention provides an effective and convenient amplitude and phase calibration method for an active phased array antenna. The setting of the method enables the active phased array antenna to perform self-calibration of amplitude and phase at any time throughout its entire service life, ensuring that the signal strength and phase of each antenna unit are consistent, thereby improving the overall accuracy of the active phased array antenna, ensuring the accuracy of the transmitting and receiving beams, and ensuring the long-term stability of the device. Through real-time monitoring and correction, the potential risk of failure is reduced, the reliability of the device is guaranteed, and the maintenance cost can be reduced, thereby being economical and practical.

[0026] Preferably, in step S1, the initializing configuration of the phased array antenna and setting its working state includes:

[0027] S11: When the working state is set to the transmitting mode, the transmitting link port and the calibration link port are correctly connected to the two ports of the vector network analyzer; when the working state is set to the receiving mode, the receiving link port and the calibration link port are correctly connected to the two ports of the vector network analyzer;

[0028] S12: The initial value of each channel is set to 0 through the amplitude and phase control unit, and then each channel is turned on in sequence, and the channel with the minimum gain value is found from all the channels, and the channel is used as the reference channel.

[0029] In the present invention, the reference channel is determined by the amplitude and phase control unit, and the reference amplitude and phase are set for calibration. The responses of all other channels can be adjusted based on this reference, and by setting the reference channel as a reference, the deviation caused by system errors or measurement inconsistencies can be reduced, thereby improving the accuracy of overall normalization. At the same time, the calibration process is simplified, ensuring that the amplitude and phase adjustments of all channels in the device are relative to the same reference, thereby reducing complexity and potential errors, helping to maintain the response consistency between the channels of the active phased array antenna, and improving the overall accuracy of the calibration, thereby improving the performance and stability of the antenna array.

[0030] Preferably, in step S3, the calibration by controlling the amplitude and phase control unit through the calibration program includes: normalizing the amplitude test and phase test of S21 in the S parameters of the vector network analyzer, and closing the reference channel through the amplitude and phase control unit, and then turning on the RF switch of each channel in turn, and adjusting the attenuator and phase shifter of the T / R component in each channel through the amplitude and phase control unit, so that the normalized amplitude of each channel is close to 0dB and the phase is close to 0°, and the attenuator value and phase shifter value of each channel at the current operating frequency are recorded respectively, so as to obtain the amplitude and phase calibration values ​​of each channel, then set other operating frequencies, and then repeat the above operations to obtain the amplitude and phase calibration values ​​of each channel at each operating frequency, so as to generate a corresponding two-dimensional calibration table.

[0031] In the present invention, by setting a vector network analyzer in the calibration link to normalize the amplitude and phase, the amplitude and phase response of each channel can be accurately measured, and the errors between different channels are eliminated through normalization. This precise calibration ensures the consistency of the signal during the transmission and reception process, and improves the overall accuracy of the active phased array antenna. In addition, the vector network analyzer can detect the amplitude and phase deviations caused by component differences or environmental factors. Through normalization, these inconsistencies can be eliminated, so that the performance of each channel reaches a consistent standard, reducing signal distortion and interference, improving signal quality, and thus improving the overall performance of the device. And the corresponding two-dimensional calibration table generated at the end can also greatly improve the calibration speed while ensuring the calibration accuracy. When re-calibration is not required, the corresponding amplitude and phase calibration values ​​can be obtained in the existing two-dimensional calibration table according to the current operating frequency, thereby effectively calibrating each channel, ensuring the consistency of the signal during the transmission and reception process, and improving the overall accuracy of the device.

[0032] Preferably, the calibration method further includes updating the database storage unit, replacing the original two-dimensional calibration table with the two-dimensional calibration table generated by the calibration in step S3 and storing it in the database storage unit. Updating the database can ensure the accuracy of the calibration, improve the overall performance and reliability of the device, reduce maintenance costs, and ensure the stable operation of the active phased array antenna in various application scenarios.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] In the present invention, a calibration link is added to the active phased array antenna device and a corresponding calibration method is used to enable the device to perform self-calibration throughout its service life cycle, correct the amplitude and phase deviations of each channel, effectively ensure the consistency of the array amplitude and phase of the device throughout its service life cycle, eliminate the problem of device performance degradation caused by amplitude and phase inconsistency due to manufacturing tolerances, aging, environmental changes, etc., and correct the influence caused by component differences, temperature changes or power supply fluctuations through calibration of each channel, so that the device maintains a consistent performance level, and can also improve signal quality, thereby improving the clarity and reliability of the overall signal.

[0035] In addition, the calibration link also has the ability of real-time calibration and dynamic adjustment. As the environmental conditions or system status change, the amplitude and phase of each channel can be adjusted instantly to ensure that the device can maintain optimal performance under various conditions. Not only that, by adding a calibration link to the device, the maintenance cost of the device can be reduced, its economic practicality can be improved, and it can be applied to various application scenarios, ensuring the stable operation of the device in various application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic structural diagram of the active phased array antenna device provided by the present invention.

[0037] Figure 2 This is a connection diagram of the amplitude and phase control unit provided by the present invention.

[0038] Figure 3 A flow chart of the calibration method for the active phased array antenna device provided by the present invention. DETAILED DESCRIPTION

[0039] The drawings of the present invention are only for illustrative purposes and should not be construed as limiting the present invention. In order to better illustrate the following embodiments, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; it is understandable to those skilled in the art that some well-known structures and their descriptions in the drawings may be omitted.

[0040] Example 1

[0041] In this embodiment, an active phased array antenna device with a built-in calibration network is provided. Figure 1 As shown, Figure 1 The active phased array antenna device provided in this embodiment is a schematic diagram of the structure, the device includes: a transmitting link, a receiving link, a calibration link and a main control unit, wherein the main control unit is Figure 1 Not shown, the main control unit is connected to the transmission link, the receiving link and the calibration link respectively, and is used to control the reception and transmission of signals and the amplitude and phase calibration of each channel;

[0042] In the calibration link, the double-balanced passive mixer, the bandpass filter, the bidirectional power amplifier and the calibration feed network are bidirectionally connected in sequence, and the calibration feed network is connected to the coupler of the transmitting link and the receiving link in a bidirectional manner. In this embodiment, setting the mixer in the calibration link as a double-balanced passive mixer can realize up and down frequency conversion of the signal, so that the transmission signal and the coupled calibration signal frequency are consistent, which is convenient for the network analyzer to test; setting the power amplifier as a bidirectional power amplifier can realize bidirectional amplification of the calibration signal, realizing bidirectional transmission of the signal in the calibration link.

[0043] The device also includes an amplitude and phase control unit and a vector network analyzer ( Figure 1 The vector network analyzer is used to connect the transmission link and the calibration link or to connect the receiving link and the calibration link, accurately measure the amplitude and phase response of each channel when calibrating the transmission link or the receiving link, and feed back the measurement results to the main control unit. The main control unit generates corresponding instructions based on the results to control the amplitude and phase control unit to perform amplitude and phase calibration on each channel.

[0044] In the active phased array antenna device, the up and down frequency conversion part is combined with the antenna array surface, which contains multiple antenna units. The signal of each unit must be synchronized at the correct amplitude and phase to achieve electronic scanning and direction control of the beam. Therefore, it is particularly important to calibrate the amplitude and phase of each channel of the antenna array surface. In the present application, a calibration link capable of bidirectional signal transmission is set in the device, so that both the transmitting link and the receiving link can be calibrated through the calibration link, and the amplitude and phase control unit is combined to enable the active phased array antenna to correct the amplitude and phase deviations of each channel at any time during use, thereby avoiding the problems of amplitude and phase inconsistency in each channel of the active phased array antenna caused by manufacturing tolerances, aging, environmental changes, etc., and the vector network analyzer is combined with the calibration link to detect the deviation in real time and calibrate and compensate in time, thereby eliminating the performance degradation caused by these inconsistencies. Problems such as improved overall accuracy of the device, ensure the accuracy of the transmitting and receiving beams, and ensure the reliability of the active phased array antenna device.

[0045] Preferably, if Figure 1 and Figure 2 As shown, the transmitting link and the receiving link also include several T / R components, and the T / R components include a radio frequency switch, a T attenuator, a T phase shifter, a power amplifier, an R attenuator, an R phase shifter, a low noise amplifier and a radio frequency switch;

[0046] The amplitude and phase control unit is respectively connected to the T attenuator, T phase shifter, R attenuator, and R phase shifter on each T / R component. When calibrating the transmission link, the amplitude and phase control unit calibrates the channel by adjusting the T attenuator and T phase shifter; when calibrating the receiving link, the amplitude and phase control unit calibrates the channel by adjusting the R attenuator and R phase shifter.

[0047] In addition, if Figure 2 As shown, in the T / R component described in this embodiment, when in the transmitting state, it works in the T attenuator, T phase shifter, and power amplifier link; when in the receiving state, it works in the R attenuator, R phase shifter, and low noise amplifier link; ensuring that the active phased array antenna device can work efficiently in these two modes. In the transmitting mode, the power amplifier can enhance the power of the transmitted signal so that the signal can be transmitted to a longer distance. In the receiving mode, the low noise amplifier can amplify the received weak signal to improve the sensitivity and signal-to-noise ratio of the receiving system, thereby ensuring that the device can operate efficiently in both the transmitting and receiving modes.

[0048] At the same time, by using the amplitude and phase control unit to adjust the phase shifter and attenuator in the T / R component, the vector network analyzer can obtain the attenuator and phase shifter calibration values ​​of the corresponding channel, simplifying the calibration process and ensuring that the amplitude and phase adjustments of all channels in the device are relative to the same reference, thereby reducing complexity and potential errors, helping to maintain the response consistency between the channels of the active phased array antenna, and improving the performance and stability of the antenna array.

[0049] Preferably, if Figure 1 As shown, the transmitting link and receiving link also include an intermediate frequency amplifier, a mixer, a bandpass filter, a power amplifier, a radio frequency switch, a power division network and an antenna unit;

[0050] Among them, in the transmission link, the signal is first amplified by the intermediate frequency amplifier and then input into the mixer, up-converted to the radio frequency frequency by the mixer, and then filtered out the local oscillator signal and other mixing signals by the bandpass filter. After amplification by the power amplifier, the radio frequency switch is turned on to the transmission link, so that the power division network is connected to the power amplifier. The power division network divides the signal amplified by the power amplifier into several channel signals and enters the corresponding T / R components for processing, and finally radiates out through the antenna unit after passing through the coupler;

[0051] In the receiving link, after the antenna unit receives the signal, it is input into the corresponding T / R component for processing after passing through the coupler, and then the power division network is used to converge multiple signals into a single port for signal synthesis. The RF switch is turned on to the receiving link so that the synthesized signal is processed in turn through the power amplifier, bandpass filter, mixer and intermediate frequency amplifier to obtain the received signal.

[0052] from Figure 1 It can be seen that the upper part of the figure is the transmitting link, and the lower part is the receiving link, and the transmitting link and the receiving link are combined with the antenna array, and the link is switched by the RF switch, which effectively reduces the size of the device, and before transmitting the signal through the antenna or receiving the signal through the antenna, a coupler is required to couple the signal. If the channel needs to be calibrated, the coupled signals of each channel enter the calibration link through the wire for calibration. In the calibration link, the calibration feed network can realize the combination or branching of the coupled signals, so that the transmitting link and the receiving link can use the built-in calibration link in the device for calibration processing, without the need to calibrate each channel separately, which effectively simplifies the calibration process of each channel in the active phased antenna system.

[0053] Preferably, from Figure 1It can be seen that the device also includes a frequency generator for generating a local oscillator signal, and is connected to the mixers in the transmitting link and the receiving link respectively through a power divider using a radio frequency switch, and is connected to the double-balanced passive mixer in the calibration link, for sending the local oscillator signal to the transmitting link, the receiving link and the calibration link; when the device works in the transmitting link, the radio frequency switch is turned on to the transmitting mixer, and when the device works in the receiving link, the radio frequency switch is turned on to the receiving mixer.

[0054] In this embodiment, a frequency generator is provided to provide accurate frequency signals for the transmission link, the reception link and the calibration link, and the signal is input into a mixer for mixing to drive the links in the antenna array to generate the required radio frequency signals.

[0055] Preferably, the device further comprises a database storage unit for storing amplitude and phase calibration data generated during calibration, so that when calibration is performed, the calibration data stored in the database storage unit can be directly read for calibration.

[0056] Further preferably, the device also includes a radio frequency switch control unit, which is used to receive and control the radio frequency switch in the device according to the instructions of the main control unit to realize the conduction of the corresponding link, so that the device can switch between different signal paths and block the signals of unselected channels to avoid signal interference.

[0057] Example 2

[0058] This embodiment provides an active phased array antenna calibration method based on the built-in calibration network of the above-mentioned device, such as Figure 3 As shown, Figure 3 A flow chart of a calibration method for an active phased array antenna device provided in this embodiment, wherein the calibration method comprises:

[0059] S1: Initialize the configuration of the phased array antenna and set its working state;

[0060] S2: Based on the set working status, the main control unit is used to determine whether recalibration is required;

[0061] S3: If it is determined that recalibration is required, the main control unit issues a calibration instruction to start the calibration program, controls the amplitude and phase control unit to perform calibration through the calibration program, generates a corresponding two-dimensional standard table and stores it in the database storage unit; if it is determined that recalibration is not required, obtains the existing two-dimensional standard table from the database storage unit;

[0062] S4: Acquire the current operating frequency and configure the attenuator value and phase shifter value of each channel according to the two-dimensional calibration table obtained in step S3, so as to calibrate each channel of the phased array antenna.

[0063] The present embodiment provides an effective and convenient method for amplitude and phase calibration of an active phased array antenna. The setting of the method enables the active phased array antenna to perform self-calibration of amplitude and phase at any time throughout its entire service life, ensuring the consistency of signal strength and phase of each antenna unit, thereby improving the overall accuracy of the device, ensuring the accuracy of the transmit and receive beams, and ensuring the long-term stability of the system. Through real-time monitoring and correction, the potential risk of failure is reduced, the reliability of the device is guaranteed, and the maintenance cost can also be reduced, thereby being economical and practical.

[0064] Preferably, in step S1, by initializing the configuration of the phased array antenna, a unified standard can be provided for subsequent amplitude and phase calibration of the channel, thereby improving the overall accuracy of the calibration, thereby improving the signal quality and effectively improving the overall performance of the device.

[0065] When the working state is set to the transmission mode, the current working transmission frequency is f0 (GHz). The transmission link port and the calibration link port are correctly connected to the two ports of the vector network analyzer. The initial value of each channel is set to 0 through the amplitude and phase control unit, and then each channel CH_1, CH_2...CH_n is opened in turn, and the channel with the minimum gain value among all channels is found, which is used as the reference channel. At this time, the channel attenuation value is The phase shifter value is Normalize the amplitude test and phase test of S21 in the S parameter of the vector network analyzer, and then close the reference channel through the amplitude and phase control unit. Turn on the channel CH_1 switch, adjust the T attenuator and T phase shifter in the channel CH_1 respectively, so that the normalized amplitude of the channel CH_1 is close to 0dB and the phase is close to 0°. The error depends on the number of attenuators and phase shifters. Note down the attenuator value and phase shifter value at this time. In this way, the amplitude and phase calibration values ​​of each channel are measured respectively. The attenuation value is and phase shifter value Then set the machine to work at other transmission frequencies fi (i=1,2...), and repeat the above operation. The measured attenuation value is: and phase shifter value Thus, a two-dimensional calibration table of attenuator values ​​and phase shifter values ​​of the transmission link at different frequencies is generated. The obtained two-dimensional calibration table of attenuator values ​​and two-dimensional calibration table of phase shifter values ​​of the transmission link are shown in Table 1 and Table 2. Finally, the obtained two-dimensional calibration table is stored in the database storage unit.

[0066]

[0067] Table 1

[0068]

[0069] Table 2

[0070] When the working state is set to receiving mode, the current working receiving frequency is f0 (GHz). The receiving link port and the calibration link port are correctly connected to the two ports of the vector network analyzer. The initial value of each channel is set to 0 through the amplitude and phase control unit, and then each channel CH_1, CH_2...CH_n is opened in turn to find the channel with the minimum gain among all channels and use it as the reference channel. At this time, the channel attenuation value is The phase shifter value is Normalize the amplitude test and phase test of S21 in the S parameter of the vector network analyzer, and then close the reference channel through the amplitude and phase control unit. Turn on the CH_1 switch, adjust the CH_1R attenuator and R phase shifter respectively, so that the normalized amplitude of the CH_1 channel is close to 0dB and the phase is close to 0°. The error depends on the number of attenuators and phase shifters. Note down the attenuator values ​​at this time. The phase shifter value is The amplitude and phase calibration values ​​of each channel are measured respectively, and the attenuation value is and phase shifter value Set the work again at other receiving frequencies fi (i=1,2...), and the measured attenuation value is: and phase shifter value Thus, a two-dimensional calibration table of attenuator values ​​and phase shifter values ​​of the receiving link at different frequencies is generated. The two-dimensional calibration table of attenuator values ​​and phase shifter values ​​of the receiving link is shown in Table 3 and Table 4. Finally, the obtained two-dimensional calibration table is stored in the database storage unit.

[0071]

[0072] Table 3

[0073]

[0074] Table 4

[0075] Therefore, during the calibration process, normalization processing is used so that the amplitude and phase calibration values ​​of each channel can be generated at each operating frequency of the active phased array antenna, and a corresponding two-dimensional calibration table can be obtained. While ensuring the calibration accuracy, the calibration speed can be greatly improved. When re-calibration is not needed, the corresponding two-dimensional calibration table can be searched in the database storage unit according to the current operating frequency, so as to obtain the corresponding amplitude and phase calibration values, effectively calibrating each channel, ensuring the consistency of the signal during the transmission and reception process, and improving the overall accuracy of the device.

[0076] Preferably, the calibration method also includes updating the database unit, replacing the original two-dimensional calibration table with the recalibrated two-dimensional calibration table and storing it in the database. Updating the database can ensure the accuracy of the calibration, improve the overall performance and reliability of the device, reduce maintenance costs, and ensure the stable operation of the active phased array antenna in various application scenarios.

[0077] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the technical solution of the present invention, and are not intended to limit the specific implementation methods of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the claims of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. An active phased array antenna device with a built-in calibration network, characterized in that: The device comprises: a transmitting link, a receiving link, a calibration link and a main control unit; wherein the main control unit is respectively connected to the transmitting link, the receiving link and the calibration link, and is used to control the reception and transmission of signals and control the amplitude and phase calibration of each channel; In the calibration link, a double-balanced passive mixer, a bandpass filter, a bidirectional power amplifier and a calibration feed network are bidirectionally connected in sequence, and the calibration feed network is connected to the couplers of the transmitting link and the receiving link in a bidirectional connection manner to realize bidirectional transmission of signals in the calibration link; The device also includes an amplitude and phase control unit and a vector network analyzer. The vector network analyzer is used to connect the transmission link and the calibration link or to connect the receiving link and the calibration link. When calibrating the transmission link or the receiving link, the amplitude and phase response of each channel is accurately measured, and the measurement results are fed back to the main control unit. The main control unit generates corresponding instructions based on the results to control the amplitude and phase control unit to perform amplitude and phase calibration on each channel.

2. The active phased array antenna device with a built-in calibration network according to claim 1, characterized in that: The transmitting link and receiving link also include several T / R components, and the T / R components include a radio frequency switch, a T attenuator, a T phase shifter, a power amplifier, an R attenuator, an R phase shifter, a low noise amplifier and a radio frequency switch; The amplitude and phase control unit is respectively connected to the T attenuator, T phase shifter, R attenuator, and R phase shifter on each T / R component. When calibrating the transmission link, the amplitude and phase control unit calibrates the channel by adjusting the T attenuator and T phase shifter; when calibrating the receiving link, the amplitude and phase control unit calibrates the channel by adjusting the R attenuator and R phase shifter.

3. The active phased array antenna device with a built-in calibration network according to claim 2, characterized in that: The transmitting link and receiving link also include an intermediate frequency amplifier, a mixer, a bandpass filter, a power amplifier, a radio frequency switch, a power division network and an antenna unit; Among them, in the transmission link, the signal is first amplified by the intermediate frequency amplifier and then input into the mixer, up-converted to the radio frequency frequency by the mixer, and then filtered out the local oscillator signal and other mixing signals by the bandpass filter. After amplification by the power amplifier, the radio frequency switch is turned on to the transmission link, so that the power division network is connected to the power amplifier. The power division network divides the signal amplified by the power amplifier into several channel signals and enters the corresponding T / R components for processing, and finally radiates out through the antenna unit after passing through the coupler; In the receiving link, after the antenna unit receives the signal, it is input into the corresponding T / R component for processing after passing through the coupler, and then the power division network is used to converge multiple signals into a single port for signal synthesis. The RF switch is turned on to the receiving link so that the synthesized signal is processed in turn through the power amplifier, bandpass filter, mixer and intermediate frequency amplifier to obtain the received signal.

4. The active phased array antenna device with a built-in calibration network according to claim 3, characterized in that: The device also includes a frequency generator for generating a local oscillator signal, and is connected to the mixers in the transmitting link and the receiving link respectively through a power divider using a radio frequency switch, and is connected to a double-balanced passive mixer in the calibration link, and is used to send the local oscillator signal to the transmitting link, the receiving link and the calibration link; When the device works in the transmission link, the radio frequency switch is turned on to the transmission mixer, and when the device works in the reception link, the radio frequency switch is turned on to the reception mixer.

5. An active phased array antenna device with a built-in calibration network according to any one of claims 1 to 4, characterized in that: The device also includes a database storage unit for storing amplitude and phase calibration data generated during calibration.

6. An active phased array antenna device with a built-in calibration network according to any one of claims 1 to 4, characterized in that: The device also includes a radio frequency switch control unit, which is used to receive and control the radio frequency switch in the device according to the instruction of the main control unit to realize the conduction of the corresponding link.

7. A calibration method for an active phased array antenna based on a built-in calibration network of the device according to any one of claims 1 to 6, characterized in that: The calibration method comprises: S1: Initialize the configuration of the phased array antenna and set its working state; S2: Based on the set working status, the main control unit is used to determine whether recalibration is required; S3: If it is determined that recalibration is required, the main control unit issues a calibration instruction to start the calibration program, controls the amplitude and phase control unit to perform calibration through the calibration program, generates a corresponding two-dimensional standard table and stores it in the database storage unit; if it is determined that recalibration is not required, obtains the existing two-dimensional standard table from the database storage unit; S4: Acquire the current operating frequency and configure the attenuator value and phase shifter value of each channel according to the two-dimensional calibration table obtained in step S3, so as to calibrate each channel of the phased array antenna.

8. The active phased array antenna calibration method with a built-in calibration network according to claim 7, characterized in that: In the step S1, the initializing configuration of the phased array antenna and setting its working state includes: S11: When the working state is set to the transmitting mode, the transmitting link port and the calibration link port are correctly connected to the two ports of the vector network analyzer; when the working state is set to the receiving mode, the receiving link port and the calibration link port are correctly connected to the two ports of the vector network analyzer; S12: Set the initial value of each channel to 0 through the amplitude and phase control unit, then turn on each channel in turn, and find the channel with the minimum gain value from all the channels, and use it as the reference channel.

9. The active phased array antenna calibration method with a built-in calibration network according to claim 8, characterized in that: In the step S3, the calibration by controlling the amplitude and phase control unit through the calibration program includes: normalizing the amplitude test and phase test of S21 in the S parameters of the vector network analyzer, and closing the reference channel through the amplitude and phase control unit, and then turning on the RF switch of each channel in turn, and adjusting the attenuator and phase shifter of the T / R component in each channel through the amplitude and phase control unit respectively, so that the normalized amplitude of each channel is close to 0dB and the phase is close to 0°, and the attenuator value and phase shifter value of each channel at the current operating frequency are recorded respectively, so as to obtain the amplitude and phase calibration values ​​of each channel, then set other operating frequencies, and then repeat the above operations to obtain the amplitude and phase calibration values ​​of each channel at each operating frequency, so as to generate the corresponding two-dimensional calibration table.

10. The active phased array antenna calibration method with a built-in calibration network according to claim 9, characterized in that: The calibration method further includes updating the database storage unit, replacing the original two-dimensional calibration table with the two-dimensional calibration table generated by the calibration in step S3 and storing the table in the database storage unit.

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