An active phased array antenna device with a built-in calibration network and a calibration method

Abstract

The present invention relates to the technical field of active phased array antennas. More specifically, it relates to an active phased array antenna device with a built-in calibration network and a calibration method, including: initializing and configuring the phased array antenna and setting its working state; according to the set working state, using the main control unit to determine whether recalibration is required; if it is determined that recalibration is required, the main control unit issues a calibration instruction to start the calibration program, controls the amplitude-phase control unit through the calibration program to perform calibration, generates a corresponding two-dimensional standard table and stores it in the database storage unit; if it is determined that recalibration is not required, obtain the existing two-dimensional standard table from the database storage unit; obtain the current operating frequency and configure the attenuator values and phase shifter values of each channel from the obtained two-dimensional calibration table, thereby calibrating each channel of the phased array antenna, achieving that the active phased array antenna can perform self-calibration of amplitude and phase at any time during the entire service life cycle.

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 link design of each channel of the active phased array antenna adopts a symmetric structure and the same link design, due to factors such as structural errors, differences in the characteristics of active devices, processing accuracy, operating frequency, and ambient temperature during use, there are significant differences in the amplitude and phase of each channel. Therefore, before leaving the factory, the active phased array antenna must be calibrated for amplitude and phase to ensure the consistency of the initial amplitude and phase of each channel, so as to improve key indicators such as the beam pointing accuracy and sidelobe of the phased array. In the prior art, usually, the active phased array antenna is calibrated by the mutual coupling calibration method or with the assistance of an external microwave anechoic chamber and an auxiliary antenna condition. This method requires an expensive microwave anechoic chamber test environment and a precise servo control drive to measure the probe, and the device complexity is also relatively high, with a high cost. In addition, since the active array antenna is applied to a device and has a long service life, during the life cycle, due to factors such as device aging, environmental impact, and the consistency of temperature and humidity response of active components, the internal conditions may change greatly. Therefore, the calibration before the active array antenna leaves the factory cannot guarantee the amplitude and phase consistency of the array throughout the life cycle. Moreover, in the field of millimeter-wave phased arrays, due to the small size and high integration of the product, the up-conversion and down-conversion parts are usually integrated with the antenna array surface, which also brings greater difficulties to the amplitude and phase calibration of the phased array antenna.

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

[0004] The present invention aims to overcome at least one defect (insufficiency) of the above prior art, and provides an active phased array antenna device with a built-in calibration network and a calibration method, which are used to solve the problems that the existing active phased array antenna relying only on the calibration before leaving the factory of the active array antenna cannot guarantee the consistency of the array amplitude and phase throughout its life cycle, 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, and the device includes: 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 band-pass filter, a bidirectional power amplifier, and a calibration feeding network are connected bidirectionally in sequence, and the calibration feeding network is connected to the couplers of the transmitting link and the receiving link in a bidirectional connection manner to realize the bidirectional transmission of signals in the calibration link;

[0007] The device further includes an amplitude-phase control unit and a vector network analyzer. The vector network analyzer is used to connect the transmitting link and the calibration link or connect the receiving link and the calibration link, accurately measure the amplitude and phase responses of each channel during the calibration of the transmitting link or the receiving link, and feed the measurement results back to the main control unit. The main control unit generates corresponding instructions according to the results to control the amplitude-phase control unit to perform amplitude-phase calibration on each channel.

[0008] In the active phased array antenna device, the up-conversion and down-conversion parts are combined with the antenna array surface. The antenna array surface contains multiple antenna elements. The signals 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 this application, by setting a calibration link in the device that can perform bidirectional signal transmission, both the transmitting link and the receiving link can be calibrated through the calibration link, and combined with the amplitude-phase control unit, the active phased array antenna can correct the amplitude and phase deviations of each channel at any time during use, avoiding problems such as inconsistent amplitude and phase that may occur in each channel of the active phased array antenna due to manufacturing tolerances, aging, environmental changes, etc. And through the vector network analyzer combined with the calibration link, the deviations that occur are detected in real time and calibrated and compensated in a timely manner, thereby eliminating problems such as performance degradation caused by these inconsistencies, improving the overall accuracy of the device, ensuring the accuracy of the transmitting and receiving beams, and ensuring the reliability of the active phased array antenna device.

[0009] Preferably, there are also several T / R components in the transmitting link and the receiving link. The T / R component includes 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-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 transmitting link, the amplitude-phase control unit calibrates the channel by adjusting the T attenuator and the T phase shifter; when calibrating the receiving link, the amplitude-phase control unit calibrates the channel by adjusting the R attenuator and the R phase shifter.

[0011] In the present invention, a amplitude-phase control unit is used to adjust the phase shifter and the attenuator, so as to obtain the calibration values of the attenuator and the phase shifter for the corresponding channels, simplify the calibration process, ensure 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.

[0012] Preferably, the transmitting link and the receiving link further include an intermediate frequency amplifier, a mixer, a band-pass filter, a power amplifier, a radio frequency switch, a power distribution network, and an antenna unit;

[0013] Wherein, in the transmitting link, the signal is first amplified by the intermediate frequency amplifier and then input into the mixer, up-converted to the radio frequency by the mixer, and then the local oscillator signal and other mixing signals are filtered out by the band-pass filter. After being amplified by the power amplifier, the radio frequency switch is turned on to the transmitting link, so that the power distribution network is connected to the power amplifier. The power distribution network divides the signal amplified by the power amplifier into several channel signals and enters the corresponding T / R module for processing. Finally, after passing through the coupler, it is radiated out through the antenna unit;

[0014] In the receiving link, after the antenna unit receives the signal, it is input into the corresponding T / R module for processing through the coupler, and then the power distribution network is used to converge multiple signals into a single port for signal synthesis. The radio frequency switch is turned on to the receiving link so that the synthesized signal passes through the power amplifier, the band-pass filter, the mixer, and the intermediate frequency amplifier in sequence for processing, thereby obtaining the received signal.

[0015] In this application, before transmitting or receiving signals through the antenna, a coupler is needed to couple the signals. If calibration of channels is required, the coupled signals of each channel enter the calibration link through wires for calibration. Among them, in the calibration link, the calibration feeding network can realize the combining or splitting of the coupled signals, 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, a frequency generator is further included in the device, which is used to generate a local oscillator signal and is respectively connected to the mixers in the transmitting link and the receiving link through a power splitter using a radio frequency switch, and is also 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 operates in the transmitting link, the radio frequency switch is turned on to the transmitting mixer, and when the device operates in the receiving link, the radio frequency switch is turned on to the receiving mixer.

[0017] In this application, a frequency generator is provided to supply precise frequency signals for the transmitting link, receiving link, and calibration link. The signals are input into a mixer for mixing, driving the links in the antenna array to generate the required radio frequency signals.

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

[0019] Preferably, the device further includes a radio frequency switch control unit for receiving and controlling the radio frequency switches in the device according to the instructions of the main control unit to achieve conduction of the corresponding links, enabling the device to switch between different signal paths and blocking 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 above-mentioned device. The calibration method includes:

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

[0022] S2: According to the set working state, use the main control unit to determine whether re-calibration is required;

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

[0024] S4: Obtain the current working frequency and configure the attenuator values and phase shifter values of each channel according to the two-dimensional calibration table obtained in step S3, thereby calibrating each channel of the phased array antenna.

[0025] The present invention provides an effective and simple amplitude-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 during its entire service life cycle, ensuring that the signal intensity 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, ensuring the long-term stability of the device, reducing the potential failure risk through real-time monitoring and correction, ensuring the reliability of the device, and also reducing the maintenance cost, having economic practicality.

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

[0027] S11: When the set working state is the transmit mode, correctly connect the transmit link port and the calibration link port to the two ports of the vector network analyzer respectively; when the set working state is the receive mode, correctly connect the receive link port and the calibration link port to the two ports of the vector network analyzer respectively.

[0028] S12: Set the initial value of each channel to 0 through the amplitude-phase control unit, then turn on each channel in sequence, and find the channel with the minimum gain from all channels, and use it as the reference channel.

[0029] In the present invention, the reference channel is determined by the amplitude-phase control unit, which sets the reference amplitude and phase for calibration. The corresponding values of all other channels can be adjusted based on this. By setting the reference channel as the reference, the deviation caused by system errors or measurement inconsistencies can also 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, improving the overall accuracy of calibration, and thus improving the performance and stability of the antenna array.

[0030] Preferably, in the step S3, the calibration by controlling the amplitude-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 then turning off the reference channel through the amplitude-phase control unit. Then turn on the RF switches of each channel in sequence, and adjust the attenuator and phase shifter of the T / R component in each channel respectively through the amplitude-phase control unit to make the normalized amplitude of each channel close to 0 dB and the phase close to 0°. Record the attenuator value and phase shifter value of each channel at the current operating frequency 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, thereby generating the corresponding two-dimensional calibration table.

[0031] In the present invention, by setting a vector network analyzer in the calibration link to perform normalization processing on the amplitude and phase, the amplitude and phase responses of each channel can be accurately measured. Through the normalization processing, the errors between different channels are eliminated. This precise calibration ensures the consistency of the signal during transmission and reception, improving the overall accuracy of the active phased array antenna. Moreover, the vector network analyzer can detect the amplitude and phase deviations caused by component differences or environmental factors. Through the normalization processing, these inconsistencies can be eliminated, enabling the performance of each channel to reach a consistent standard, reducing signal distortion and interference, improving the signal quality, and thus enhancing the overall performance of the device. Additionally, the generated corresponding two-dimensional calibration table can greatly improve the calibration speed while ensuring the calibration accuracy. When recalibration is not required, the corresponding amplitude and phase calibration values can be obtained from the existing two-dimensional calibration table according to the current operating frequency, effectively calibrating each channel, ensuring the consistency of the signal during transmission and reception, 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 in step S3 and storing it in the database storage unit. By updating the database, the calibration accuracy can be ensured, the overall performance and reliability of the device can be improved, the maintenance cost can be reduced, and the stable operation of the active phased array antenna in various application scenarios can be ensured.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] In the present invention, by adding a calibration link in the active phased array antenna device and according to the corresponding calibration method, the device can perform self-calibration throughout its service life cycle, correcting the amplitude and phase deviations of each channel, effectively ensuring the consistency of the array amplitude and phase throughout the service life cycle of the device, eliminating problems such as performance degradation of the device caused by inconsistencies in amplitude and phase due to manufacturing tolerances, aging, environmental changes, etc. By calibrating each channel, the impacts caused by component differences, temperature changes, or power fluctuations can be corrected, enabling the device to maintain a consistent performance level, and also improving the signal quality, thereby enhancing 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 states change, the amplitude and phase of each channel can be adjusted immediately to ensure that the device can maintain the best performance under various conditions. Moreover, by adding a calibration link in the device, the maintenance cost of the device can be reduced, its economic practicality can be improved, it can be applied to various different application scenarios, and the stable operation of the device in various application scenarios can be ensured. Brief Description of the Drawings

[0036] Figure 1 Schematic structural diagram of the active phased array antenna device provided by the present invention.

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

[0038] Figure 3 Flowchart of the calibration method for the active phased array antenna device provided by the present invention. Detailed implementation manners

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

[0040] Embodiment 1

[0041] In this embodiment, an active phased array antenna device with a built-in calibration network is provided. As Figure 1 shown, Figure 1 Schematic structural diagram of the active phased array antenna device provided by this embodiment. The device includes: a transmitting link, a receiving link, a calibration link, and a main control unit. Among them, the main control unit is not marked in Figure 1 , and 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;

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

[0043] The device further includes an amplitude and phase control unit and a vector network analyzer (not marked in Figure 1 ). The vector network analyzer is used to connect the transmitting link and the calibration link or connect the receiving link and the calibration link. When calibrating the transmitting link or the receiving link, it accurately measures the amplitude and phase responses of each channel and feeds the measurement results back to the main control unit. The main control unit generates corresponding instructions according to the results to control the amplitude and phase control unit to perform amplitude and phase calibration on each channel.

[0044] In an active phased array antenna device, the up-conversion and down-conversion parts are integrated with the antenna array surface. The antenna array surface contains multiple antenna elements. The signals of each element 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 this application, by setting a calibration link that can perform bidirectional signal transmission in the device, both the transmitting link and the receiving link can be calibrated through the calibration link. And by combining the amplitude and phase control unit, the active phased array antenna can correct the amplitude and phase deviations of each channel at any time during use, avoiding problems such as inconsistent amplitude and phase that may occur in each channel of the active phased array antenna due to manufacturing tolerances, aging, environmental changes, etc. And by using a vector network analyzer in combination with the calibration link to detect the deviations that occur in real time and perform calibration compensation in a timely manner, the performance degradation and other problems caused by these inconsistencies are eliminated, the overall accuracy of the device is improved, the accuracy of the transmitting and receiving beams is ensured, and the reliability of the active phased array antenna device is guaranteed.

[0045] Preferably, as Figure 1 and Figure 2 shown, there are also several T / R modules in the transmitting link and the receiving link. The T / R module includes 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 module. When calibrating the transmitting link, the amplitude and phase control unit calibrates the channel by adjusting the T attenuator and the T phase shifter; when calibrating the receiving link, the amplitude and phase control unit calibrates the channel by adjusting the R attenuator and the R phase shifter.

[0047] In addition, as Figure 2 shown, in the T / R module of this embodiment, when in the transmitting state, it works on the T attenuator, T phase shifter, and power amplifier link; when in the receiving state, it works on 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 propagate to a farther 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, thus ensuring that the device can operate efficiently in both the transmitting and receiving modes.

[0048] Meanwhile, by using the amplitude-phase control unit to adjust the phase shifters and attenuators in the T / R module, the vector network analyzer can obtain the calibration values of the attenuators and phase shifters for the corresponding channels, simplifying the calibration process and ensuring that the amplitude and phase adjustments for all channels in the device are relative to the same reference, thereby reducing complexity and potential errors, helping to maintain the response consistency among the channels of the active phased array antenna, and improving the performance and stability of the antenna array.

[0049] Preferably, as Figure 1 shown, the transmit link and the receive link further include intermediate frequency amplifiers, mixers, band-pass filters, power amplifiers, RF switches, power distribution networks, and antenna elements;

[0050] Among them, in the transmit link, the signal is first amplified by the intermediate frequency amplifier and then input into the mixer, where it is up-converted to the radio frequency by the mixer, and then the local oscillator signal and other mixing signals are filtered out by the band-pass filter. After being amplified by the power amplifier, the RF switch conducts to the transmit link, enabling the power distribution network to be connected to the power amplifier. The power distribution network divides the signal amplified by the power amplifier into several channel signals and enters the corresponding T / R modules for processing. Finally, after passing through the coupler, it is radiated out through the antenna element;

[0051] In the receive link, after the antenna element receives the signal, it is input into the corresponding T / R module for processing through the coupler, and then the power distribution network is used to converge multiple signals into a single port for signal synthesis. The RF switch conducts to the receive link to enable the synthesized signal to pass through the power amplifier, band-pass filter, mixer, and intermediate frequency amplifier in sequence for processing, thereby obtaining the received signal.

[0052] As can be seen from Figure 1 it, the upper half of the figure is the transmit link, and the lower half is the receive link. Moreover, the transmit link and the receive link are integrated with the antenna array surface, and the link switching is performed through the RF switch, effectively reducing the size of the device. Before transmitting or receiving signals through the antenna, it is also necessary to use the coupler to couple the signals. If calibration of the channels is required, the coupled signals of each channel enter the calibration link through wires for calibration. Among them, in the calibration link, the calibration feeding network can perform signal combining or splitting on the coupled signals, so that both the transmit link and the receive link can use the built-in calibration link in the device for calibration processing, without the need to calibrate each channel individually, effectively simplifying the calibration process for each channel in the active phased antenna system.

[0053] Preferably, from Figure 1It can be seen that a frequency generator is further included in the device, which is used to generate 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 also 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 operates in the transmitting link, the radio frequency switch is turned on to the transmitting mixer, and when the device operates in the receiving link, the radio frequency switch is turned on to the receiving mixer.

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

[0055] Preferably, the device further includes a database storage unit, which is used to store the amplitude-phase calibration data generated during calibration, so that the calibration data stored in the database storage unit can be directly read for calibration when calibration is performed.

[0056] Further preferably, the device further 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 achieve conduction of the corresponding link, so that the device can switch between different signal paths and block the signals of the unselected channels to avoid signal interference.

[0057] Embodiment 2

[0058] This embodiment provides an active phased array antenna calibration method based on the built-in calibration network of the above-mentioned device, as Figure 3 shown, Figure 3 is the flowchart of the calibration method for the active phased array antenna device provided in this embodiment. The calibration method includes:

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

[0060] S2: According to the set working state, use the main control unit to judge whether re-calibration is required;

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

[0062] S4: Obtain the current working frequency and configure the attenuator values and phase shifter values 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] This embodiment provides an effective and simple amplitude-phase calibration method for an active phased array antenna. The implementation of this method enables the active phased array antenna to perform self-calibration of amplitude and phase at any time during its entire service life cycle, ensuring that the signal intensities and phases of each antenna element are consistent, thereby improving the overall accuracy of the device, ensuring the accuracy of the transmitting and receiving beams, ensuring the long-term stability of the system, reducing potential failure risks through real-time monitoring and correction, ensuring the reliability of the device, and also reducing maintenance costs, with economic practicality.

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

[0065] When its working state is set to the transmit mode, the current working transmit frequency is f0 (GHz). The transmit link port and the calibration link port are correctly connected to the two ports of the vector network analyzer respectively. The initial values of each channel are set to 0 through the amplitude-phase control unit, and then each channel CH_1, CH_2...CH_n is turned on in sequence to find the channel with the minimum gain among all channels, and this is used as the reference channel. At this time, the attenuation value of this channel is The value of the phase shifter is The amplitude test and phase test of S21 in the S-parameters of the vector network analyzer are normalized. At this time, the reference channel is closed through the amplitude-phase control unit. The switch of channel CH_1 is turned on, and the T attenuator and T phase shifter in channel CH_1 are adjusted respectively to make the normalized amplitude of channel CH_1 close to 0 dB and the phase close to 0°. The error depends on the number of bits of the attenuator and the phase shifter. At this time, the attenuator value is recorded as, and the phase shifter value is recorded as. The amplitude and phase calibration values of each channel are measured respectively, and the attenuation value is And the phase shifter value Then, the working frequency is set to other transmit frequencies fi (i = 1, 2...), and then the above operations are repeated to measure the attenuation values as: And the phase shifter values Thus, a two-dimensional calibration table of the attenuator values and phase shifter values of the transmit link at different frequencies is generated. The obtained two-dimensional calibration table of the attenuator values and phase shifter values of the transmit link is 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 its working state is set to the 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 respectively. The initial values of each channel are set to 0 through the amplitude-phase control unit, and then each channel CH_1, CH_2... CH_n is turned on in sequence to find the channel with the minimum gain among all channels, and this is used as the reference channel. At this time, the attenuation value of this channel is The phase shifter value is Normalize the amplitude test and phase test of S21 in the S-parameters of the vector network analyzer. At this time, close the reference channel through the amplitude-phase control unit. Turn on the switch of channel CH_1, and adjust the attenuator and R phase shifter of channel CH_1 respectively to make the normalized amplitude of channel CH_1 close to 0 dB and the phase close to 0°. The error depends on the number of bits of the attenuator and the phase shifter. Record the attenuator value at this time as The phase shifter value is Measure the amplitude and phase calibration values of each channel respectively in this way. The attenuation value is And the phase shifter value Set the working frequency to other receiving frequencies fi (i = 1, 2...) again, and the measured attenuation value is: And the phase shifter value Thereby generating a two-dimensional calibration table of the attenuator values and phase shifter values of the receiving link at different frequencies. The two-dimensional calibration table of the attenuator values and phase shifter values of the receiving link is shown in Table 3 and Table 4. Finally, store the obtained two-dimensional calibration table in the database storage unit.

[0071]

[0072] Table 3

[0073]

[0074] Table 4

[0075] Thus, through normalization during the calibration process, amplitude and phase calibration values of each channel can be generated at each working frequency of the active phased array antenna, and the corresponding two-dimensional calibration table can be obtained. While ensuring the calibration accuracy, it can greatly improve the calibration speed. When no re-calibration is required, the corresponding two-dimensional calibration table can be searched in the database storage unit according to the current working frequency, so as to obtain the corresponding amplitude and phase calibration values, effectively calibrate each channel, ensure the consistency of the signal during transmission and reception, and improve the overall accuracy of the device.

[0076] Preferably, the calibration method further includes the update of the database unit, replacing the original two-dimensional calibration table with the newly generated two-dimensional calibration table through recalibration and storing it in the database. Updating the database can ensure the calibration accuracy, improve the overall performance and reliability of the device, reduce the maintenance cost, 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 solutions of the present invention, rather than limitations on the specific implementation manners of the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the claims of the present invention shall be included within 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, wherein 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, and the main control unit generates corresponding instructions according to the results to control the amplitude and phase control unit to perform amplitude and phase calibration on each channel; The main control unit generates corresponding instructions according to the results to control the amplitude and phase control unit to perform amplitude and phase calibration on each channel, including: 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, wherein the reference channel sets the initial value of each channel to 0 through the amplitude and phase control unit, and then opens each channel in turn, and finds the channel with the minimum gain value from all channels to obtain it; then turns on the RF switch of each channel in turn, and adjusts 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 the corresponding two-dimensional calibration table.

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. In the transmitting link, the T / R component includes a first radio frequency switch, a T attenuator, a T phase shifter, a power amplifier, and a second radio frequency switch connected in sequence; in the receiving link, the T / R component includes a first radio frequency switch, an R attenuator, an R phase shifter, a low noise amplifier, and a second radio frequency switch connected in sequence; 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 calibration table and stores it in the database storage unit; if it is determined that recalibration is not required, obtains the existing two-dimensional calibration 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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