Phased-array antenna emission calibration method with built-in local oscillator and electronic equipment

Abstract

The invention relates to the technical field of phased-array antennas, in particular to a phased-array antenna emission calibration method with a built-in local oscillator and electronic equipment, and the method comprises the following steps: building and configuring a test system, enabling a receiving antenna to be located on the central axis of the phased-array antenna, and enabling the receiving antenna to be connected with a frequency spectrograph; the phased-array antenna is divided according to the layout of the phased-array antenna, the phased-array antenna is divided into a plurality of centrosymmetric annular areas according to the central axis of the phased-array antenna, each annular area is provided with one or more centrosymmetric subunits, and each subunit comprises a plurality of antenna channels with the same number; a phased-array antenna is used for transmitting signals, a receiving antenna is used for receiving signals, amplitude and phase calibration is carried out on antenna channels in subunits of an annular area, the subunits of the annular area and different annular areas respectively, and transmitting calibration of the whole phased-array antenna is achieved. According to the invention, the problem of difficulty in signal synchronization in a traditional vector network analyzer test system is effectively solved.

Description

Technical Field

[0001] The present application relates to the technical field of phased array antennas, and in particular to a method for calibrating the transmission of a phased array antenna with a built-in local oscillator and electronic equipment. Background Art

[0002] Phased array antennas form controllable beams by adjusting the phase and amplitude of each array element. Compared with mechanical scanning, phased array antennas not only improve scanning speed and flexibility, but also can generate multiple beams. Therefore, they are widely used in many fields such as radar, satellite communications and wireless communications. However, with the improvement of the integration of large-scale phased array antennas, the problem of phase and amplitude errors has gradually become prominent, which will lead to distortion of the radiation pattern and degradation of system performance. Therefore, accurate phase and amplitude calibration is particularly important.

[0003] With the growing demand for high integration and miniaturization, the application of AIP (Antenna in Package) technology is becoming more and more widespread. Due to space limitations, AIP usually does not reserve ports for phased array amplitude and phase testing. In order to further improve integration and reduce costs, many solutions have adopted built-in local oscillator technology. However, there is a frequency deviation and random jitter between the built-in local oscillator and the instrument signal. The use of higher-specification devices and more optimized circuit design can reduce this frequency deviation.

[0004] Vector network analyzer is a common device for measuring antenna parameters. Its testing principle is to obtain various parameters of the antenna by measuring the S parameters of the link and performing data processing. In VNA measurement, in order to ensure the dynamic range of the test, the intermediate frequency bandwidth needs to be set to a smaller range, such as 1KHz. At this time, the difference between the output frequency of the VNA (such as port 1 output) and the receiving frequency (such as port 2 input) needs to be kept within the intermediate frequency bandwidth of 1KHz, and signals outside this range will be filtered out. When testing phased array antennas without built-in local oscillators, since the output and input frequencies are both generated by the VNA, there is no frequency difference, and the test can be carried out smoothly.

[0005] However, when testing a phased array antenna with a built-in local oscillator, the output frequency of the built-in phased array antenna needs to be configured to the vector network output frequency, and the vector network then receives at the receiving frequency. But when the phased array to be tested uses a built-in local oscillator, since the crystal oscillator is not shared with the vector network, there is a significant frequency deviation between the output frequency of the phased array antenna and the output frequency of the vector network, even if the target frequency values ​​configured for the two are the same. This deviation usually exceeds the intermediate frequency bandwidth range.

[0006] In addition, the local oscillator crystal built into the phased array antenna is usually not a high-specification crystal similar to that used in the measuring instrument in order to maintain cost-effectiveness. This leads to significant frequency jitter over time, which in turn increases the instability of the frequency deviation, causing the deviation to further expand. In this case, the receiving function of the vector network analyzer will not be realized, making the entire test process impossible. Therefore, there is an urgent need to develop a transmission calibration method for phased array antennas with built-in local oscillators. Summary of the invention

[0007] In view of the deficiencies in the prior art, the present invention discloses a phased array antenna transmission calibration method with a built-in local oscillator and an electronic device, which are used to solve the above problems.

[0008] The present invention is achieved through the following technical solutions: An embodiment of the present invention provides a method for calibrating a phased array antenna transmission with a built-in local oscillator, comprising the following steps: Build and configure the test system, where the receiving antenna is located on the central axis of the phased array antenna, and the receiving antenna is connected to the spectrum analyzer; The phased array antenna is divided according to its layout, and is divided into a plurality of centrosymmetric annular regions according to the central axis of the phased array antenna, and each annular region has one or more centrosymmetric subunits, and each subunit includes a plurality of antenna channels of the same number; The phased array antenna is used to transmit signals and the receiving antenna is used to receive signals. The amplitude and phase calibration are performed between the antenna channels in the sub-units of the annular area, between the sub-units of the annular area, and between different annular areas, so as to realize the transmission calibration of the entire phased array antenna.

[0009] As an optional implementation, the test system includes a phased array antenna, a receiving antenna, a spectrum analyzer and a control computer. The receiving antenna is connected to the spectrum analyzer. One end of the control computer is connected to the phased array antenna for configuring and controlling different antenna channels of the phased array antenna to transmit signals. The other end of the control computer is connected to the spectrum analyzer for obtaining amplitude and phase signals corresponding to the receiving antenna using the spectrum analyzer.

[0010] As an optional embodiment, the annular area has multiple centrally symmetrical sub-units, which specifically include corner units, x-axis mirror units and y-axis mirror units. The corner units are multiple antenna channels located at the four corners of the annular area, the x-axis mirror units are multiple antenna channels located in the x-axis direction of the annular area and are centrally symmetrical, and the y-axis mirror units are multiple antenna channels located in the y-axis direction of the annular area and are centrally symmetrical.

[0011] As an optional implementation, in the method, a first calibration is performed within the corner unit, the x-axis mirror unit, and the y-axis mirror unit, respectively, to obtain a first amplitude control value and a first phase control value of the corresponding antenna channel; a second calibration is performed between sub-units in the same annular area to obtain a second amplitude control value and a second phase control value of the corresponding antenna channel; a third calibration is performed between different annular areas to obtain a third amplitude control value and a third phase control value of the corresponding antenna channel; the first amplitude control value, the second amplitude control value, and the third amplitude control value are added to obtain a final amplitude control value, and the first phase control value, the second phase control value, and the third phase control value are added to obtain a final phase control value, thereby achieving the entire phased array antenna transmit calibration.

[0012] As an optional implementation, in the method, when performing the first calibration in the corner unit, the following steps are included: Open the first corner antenna channel, close other antenna channels, set a specific power attenuation, transmit the signal and measure the first corner power P1 of the receiving antenna; Open the second corner antenna channel, close other antenna channels, transmit signals and adjust attenuation until the second corner power of the receiving antenna is equal to P1, and obtain the first amplitude control value corresponding to the second corner antenna channel; Open the first corner antenna channel and the second corner antenna channel, close other antenna channels, fix the phase of the first corner antenna channel, adjust the phase of the second corner antenna channel, record the first phase control values ​​corresponding to the two antenna channels when the power is maximum, and complete the first calibration of the second corner antenna channel; The first corner antenna channel and other corner antenna channels in the corner unit are opened in sequence and simultaneously, and the above steps are repeated to complete the first calibration of other corner antenna channels.

[0013] As an optional implementation, in the method, when performing the first calibration in the x-axis mirror unit, the following steps are included: Open the first x-axis antenna channel, close other antenna channels, set a specific power attenuation, transmit a signal and measure the first x-axis power P2 of the receiving antenna; Open the second x-axis antenna channel, close other antenna channels, transmit signals and adjust attenuation until the second x-axis power of the receiving antenna is equal to P2, and obtain the first amplitude control value corresponding to the second x-axis antenna channel; Open the first x-axis antenna channel and the second x-axis antenna channel, close other antenna channels, fix the phase of the first x-axis antenna channel, adjust the phase of the second x-axis antenna channel, record the first phase control values ​​of the two antenna channels when the power is maximum, and complete the first calibration of the second x-axis antenna channel; The first x-axis antenna channel and other x-axis antenna channels in the x-axis mirror unit are opened in sequence and simultaneously, and the above steps are repeated to complete the first calibration of other x-axis antenna channels.

[0014] As an optional implementation, in the method, when performing the first calibration in the y-axis mirror unit, the following steps are included: Open the first y-axis antenna channel, close other antenna channels, set a specific power attenuation, transmit a signal and measure the first y-axis power P3 of the receiving antenna; Open the second y-axis antenna channel, close other antenna channels, transmit signals and adjust attenuation until the second y-axis power of the receiving antenna is equal to P3, and obtain the first amplitude control value corresponding to the second y-axis antenna channel; Open the first y-axis antenna channel and the second y-axis antenna channel, close other antenna channels, fix the phase of the first y-axis antenna channel, adjust the phase of the second y-axis antenna channel, record the first phase control values ​​of the two antenna channels when the power is maximum, and complete the first calibration of the second y-axis antenna channel; The first y-axis antenna channel and other y-axis antenna channels in the y-axis mirror unit are opened in sequence and simultaneously, and the above steps are repeated to complete the first calibration of other y-axis antenna channels.

[0015] As an optional implementation, in the method, when performing the second calibration between sub-units in the same annular area, the following steps are included: Open all antenna channels corresponding to a calibrated sub-unit in the same annular area, close other antenna channels, transmit signals and measure the sub-unit power P5 of the receiving antenna using a spectrum analyzer; Close all antenna channels corresponding to a subunit in the same annular area, open all antenna channels corresponding to any one of the other calibrated subunits, and synchronously control the amplitude attenuation control of all corresponding antenna channels until the measured value of the spectrum analyzer is a 1 *P5, factor , D is the phase center distance from the receiving antenna to the phased array antenna, d 2 is the distance from the phase center of the other subunits to the phase center of the phased array antenna; d 1 Obtaining a corresponding second amplitude control value for the distance from a phase center of a subunit in the same annular region to the phase center of the phased array antenna; Synchronously open all antenna channels corresponding to the subunits that have completed amplitude calibration, keep the amplitude and phase of all antenna channels of one of the subunits unchanged, synchronously change the phase of all antenna channels of another subunit, record the second phase control value of the other subunit when the power is maximum, and complete the calibration of another subunit in the same annular area; All antenna channels corresponding to a subunit in the same annular area and all antenna channels corresponding to another subunit in the same annular area are opened in sequence and simultaneously, and the above steps are repeated to complete the second calibration of all subunits in the same annular area.

[0016] As an optional implementation, in the method, when performing the third calibration between different annular areas, the following steps are included: Open all antenna channels of a subunit in the first annular area after calibration, close other antenna channels, transmit signals and measure the power P6 of a subunit in the first annular area obtained by the receiving antenna using a spectrum analyzer; Close all antenna channels of a subunit in the first annular area, open all antenna channels of a subunit in a different annular area after calibration, and synchronously control the amplitude attenuation control of all corresponding antenna channels until the measured value of the spectrum analyzer is a 3 *P6, factor , D is the phase center distance from the receiving antenna to the phased array antenna, d 4 is the distance from the phase center of a subunit corresponding to different annular regions to the phase center of the phased array antenna; d 1 For the distance from the phase center of a subunit corresponding to the first annular area to the phase center of the phased array antenna, obtain a third amplitude control value of a subunit corresponding to a different annular area; Synchronously open all antenna channels after the amplitude calibration is completed, keep the amplitude and phase of all antenna channels of a subunit of the first annular area unchanged, synchronously change the phase of all antenna channels of a subunit of different annular areas, record the third phase control value of a subunit corresponding to different annular areas when the power is maximum, and complete the third calibration corresponding to different annular areas; All antenna channels corresponding to a subunit of the first annular area and all antenna channels corresponding to a subunit of other annular areas are opened in sequence and simultaneously, and the above steps are repeated to complete the third calibration of all annular areas.

[0017] As an optional implementation, the phase centers of the centrosymmetric sub-units coincide with the physical center of the phased array antenna.

[0018] As an optional implementation, it also includes: adopting a multi-frequency point calibration method to perform multiple calibrations at different frequency points.

[0019] The present invention also provides an electronic device, characterized in that it includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, the memory is coupled to the processor, and when the processor executes the computer program, the above-mentioned phased array antenna transmission calibration method for the built-in local oscillator is implemented.

[0020] The beneficial effects of the present invention are: The present invention divides the phased array antenna according to its layout to form a plurality of different sub-units, and the receiving antenna is located on the central axis of the phased array antenna. The amplitude and phase calibration are respectively performed within the sub-units of the annular area, between the sub-units of the annular area, and between different annular areas, thereby realizing the transmission calibration of the entire phased array antenna. When executing the calibration procedure, the receiving antenna does not need to perform any movement operation. Since the logical basis of the calibration process is to ensure that the path phase difference of the antenna units at geometrically symmetrical positions is zero when receiving signals. This means that when the signals arrive at the receiving antenna units from different antenna channels of the phased array antenna, their arrival time is consistent, thereby ensuring the consistency of the phase. In addition, the phase centers of each geometrically symmetrical sub-unit should coincide with the physical center of the entire phased array antenna. Such a design can ensure that the propagation path and phase difference of the signal in each sub-unit are accurately controlled and coordinated, so that the performance of the entire antenna system is optimized. This design significantly improves the efficiency of the calibration operation, making the entire process more efficient and convenient, especially for phased array systems with integrated local oscillators.

[0021] The present invention effectively solves a core problem in the traditional vector network analyzer (VNA) test system, namely, the signal synchronization problem. Thanks to the above-mentioned phased array antenna calibration method, the first calibration is performed in the corner unit, the x-axis mirror unit, and the y-axis mirror unit, respectively, to obtain the first amplitude control value and the first phase control value of the corresponding antenna channel; the second calibration is performed between the sub-units in the same annular area, to obtain the second amplitude control value and the second phase control value of the corresponding antenna channel; the third calibration is performed between different annular areas, to obtain the third amplitude control value and the third phase control value of the corresponding antenna channel; the first amplitude control value, the second amplitude control value, and the third amplitude control value are added to obtain the final amplitude control value, and the first phase control value, the second phase control value, and the third phase control value are added to obtain the final phase control value, thereby realizing the transmission calibration of the entire phased array antenna. The calibration technology of the present invention is not only applicable to the phased array system with integrated local oscillator, but can also be widely used in the calibration operations of various highly integrated active phased array radars (AIP phased arrays). Therefore, the present invention has broad application prospects and practical application value in the field of radar system calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic diagram of the structure of the test system of the present invention; Figure 2 is a structural diagram of a phased array antenna according to an embodiment of the present invention divided according to its layout; Figure 3 It is the superposition of signals of the same frequency in the embodiment of the present invention, and the amplitude of the synthesized signal presents a periodic change amplitude diagram along with the phase difference; Figure 4 is a schematic diagram of the principle of calibrating the antenna channels corresponding to the corner units in the second annular area of ​​an embodiment of the present invention; Figure 5 It is a schematic diagram of the principle of calibrating the antenna channel corresponding to the x-axis mirror unit in the second annular area of ​​an embodiment of the present invention; Figure 6 It is a schematic diagram of the principle of calibrating the antenna channel corresponding to the y-axis mirror unit in the second annular area of ​​an embodiment of the present invention; Figure 7 It is a schematic diagram of the principle of calibrating the antenna channels corresponding to the corner units in the first annular area of ​​an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] In the embodiment of the present invention, see Figure 1 As shown, the test system includes a phased array antenna 10, a receiving antenna 20, a spectrum analyzer 30 for acquiring signals, and a control computer 40. In the transmission calibration method, the receiving antenna 20 is connected to the spectrum analyzer 30, one end of the control computer 40 is connected to the phased array antenna 10, and is used to configure and control different antenna channels of the phased array antenna 10 to transmit signals, and the other end of the control computer 40 is connected to the spectrum analyzer 30, and the spectrum analyzer 30 is used to obtain the amplitude and phase signals corresponding to the receiving antenna 20.

[0026] The embodiment of the present invention first provides a method for calibrating the transmission of a phased array antenna with a built-in local oscillator, comprising the following steps: Build and configure the test system, where the receiving antenna is located on the central axis of the phased array antenna, and the receiving antenna is connected to the spectrum analyzer; The phased array antenna is divided according to its layout, and is divided into a plurality of centrosymmetric annular regions according to the central axis of the phased array antenna, and each annular region has one or more centrosymmetric subunits, and each subunit includes a plurality of antenna channels of the same number; The phased array antenna is used to transmit signals and the receiving antenna is used to receive signals. The amplitude and phase calibration are performed between the antenna channels in the sub-units of the annular area, between the sub-units of the annular area, and between different annular areas, so as to realize the transmission calibration of the entire phased array antenna.

[0027] Specifically, a test system is built and configured, where the receiving antenna 20 is located on the central axis of the phased array antenna 10, and the receiving antenna 20 is connected to the spectrum analyzer 30. According to the adjustment of the signal and jitter parameters transmitted by the phased array antenna, the phased array antenna 10 is used to transmit the signal, and the receiving antenna 20 is used to receive the signal. The amplitude and phase calibration are performed between the antenna channels within the subunits of the annular area, between the subunits of the annular area, and between different annular areas, so as to realize the transmission calibration of the entire phased array antenna.

[0028] The phased array antenna is divided according to its layout, and is divided into a plurality of centrosymmetric annular regions according to the central axis of the phased array antenna, and each annular region has one or more centrosymmetric subunits, and each subunit includes a plurality of antenna channels of the same number; The phased array antenna is used to transmit signals, and amplitude and phase calibration is performed within the sub-units of the annular area, between the sub-units of the annular area, and between different annular areas, so as to realize the transmission calibration of the entire phased array antenna.

[0029] In this embodiment, during the process of constructing and configuring the test system, the receiving antenna 20 needs to be accurately placed at the central axis position of the phased array antenna 10. In addition, the receiving antenna 20 needs to be placed at the far-field working distance of the phased array antenna 10, because the far-field working distance can provide a uniform plane wave, thereby ensuring the accuracy and consistency of the test data.

[0030] In order to ensure that the performance of the phased array antenna 10 meets expectations, we need to use the spectrum analyzer 30 to detect its operating frequency. Specifically, the spectrum analyzer 30 is used to accurately measure the response characteristics of the phased array antenna 10 at different frequencies. Before performing frequency detection, we also need to adjust the bandwidth and power measurement parameters of the spectrum analyzer to ensure the accuracy and reliability of the measurement results. When the phased array antenna is connected to the control computer and appropriate transmission parameters such as frequency, power and modulation are set, the phased array antenna is started so that some antenna channels of the phased array antenna begin to transmit signals. At this time, the spectrum analyzer will receive the signal from the receiving antenna and analyze it in real time.

[0031] In this embodiment, the frequency range of the spectrum analyzer is set to the maximum signal capture mode according to the signal characteristics and jitter parameters of the phased array antenna 100 a , and the measured maximum power value is recorded and transmitted to the control computer 40 .

[0032] In this embodiment, in order to further improve the accuracy and efficiency of calibration, we use an automated calibration process. The control computer automatically controls the entire calibration process through a dedicated software program. The program can automatically adjust the settings of the spectrum analyzer according to preset test parameters and monitor the test data in real time.

[0033] First, the control computer 40 sets the frequency range of the spectrum analyzer 30 to the operating frequency range of the phased array antenna and adjusts it to the maximum signal capture mode. Then, the control computer 40 controls the phased array antenna 10 to start transmitting signals. The spectrum analyzer receives and analyzes the signals in real time, transmits the analysis results to the control computer, and the control computer controls the phased array antenna to complete the calibration.

[0034] Reference Figure 2 As shown, the phased array antenna used in this embodiment is a 4*4 array, including 16 antenna channels. In other embodiments, the phased array antenna may also be of other specifications, such as a 6*6 array or an 8*8 array.

[0035] In this embodiment, the phased array antenna is divided into two annular areas, a first annular area Ring1 located in the middle and a second annular area Ring2 located on the periphery, wherein the second annular area includes three centrally symmetrical sub-units - a corner unit, an x-axis mirror unit and a y-axis mirror unit, the second annular area corner unit includes four corner antenna channels located at the corner position of the second annular area, the second annular area x-axis mirror unit includes four x-axis antenna channels located in the x-axis direction of the second annular area, the second annular area y-axis mirror unit includes four y-axis antenna channels located in the y-axis direction of the second annular area, and the first annular area includes a first annular area corner unit, including four corner antenna channels located at the corner position of the first annular area.

[0036] In other embodiments, when the phased array antenna is of other specifications, such as 6*6 or 8*8, the phased array antenna is divided into 3, 4 or even more annular areas, and each outer annular area includes multiple sub-units, specifically a corner unit, one or more x-axis mirror units and a y-axis mirror unit, wherein the number of antenna channels of different sub-units is the same, for example, all are 4, and the phase center of each centrally symmetrical sub-unit coincides with the physical center of the phased array antenna.

[0037] In this embodiment, calibration is performed within the corner unit corresponding to different annular regions of the phased array antenna, calibration is performed within the x-axis mirror unit, calibration is performed within the y-axis mirror unit, calibration is performed between sub-units in the same annular region, and calibration is performed between different annular regions.

[0038] Specifically, a first calibration is performed within the corner unit, the x-axis mirror unit, and the y-axis mirror unit, respectively, to obtain a first amplitude control value and a first phase control value of the corresponding antenna channel; a second calibration is performed between sub-units in the same annular area, to obtain a second amplitude control value and a second phase control value of the corresponding antenna channel; a third calibration is performed between different annular areas, to obtain a third amplitude control value and a third phase control value of the corresponding antenna channel; the first amplitude control value, the second amplitude control value, and the third amplitude control value are added to obtain a final amplitude control value, and the first phase control value, the second phase control value, and the third phase control value are added to obtain a final phase control value, thereby achieving transmit calibration of the entire phased array antenna.

[0039] Specifically, refer to Figure 4 As shown, when performing the first calibration in the second annular area corner unit, the following steps are included: Open the first corner antenna channel 1, close other antenna channels, set power attenuation. In this embodiment, the power attenuation is at the middle level, recorded as AA1. Transmit the signal and measure the first corner power P1 obtained by the receiving antenna. At the same time, the power attenuation described below in this scheme is attenuated to the middle level, recorded as AA1, which will not be elaborated below.

[0040] Open the second corner antenna channel 4, close other antenna channels, transmit signals and adjust attenuation until the second corner power obtained by the receiving antenna is equal to P1, and obtain the corresponding first amplitude control value; Open the first corner antenna channel 1 and the second corner antenna channel 4, close other antenna channels, fix the phase of the first corner antenna channel 1, adjust the phase of the second corner antenna channel 4, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the second corner antenna channel 4.

[0041] Continue to open the third corner antenna channel 16, close other antenna channels, transmit signals and adjust attenuation until the third corner power is equal to P1, and obtain the corresponding first amplitude control value; Open the first corner antenna channel 1 and the third corner antenna channel 16, close other antenna channels, fix the phase of the first corner antenna channel 1, adjust the phase of the third corner antenna channel 16, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the third corner antenna channel 16.

[0042] Continue to open the fourth corner antenna channel 13, close other antenna channels, transmit signals and adjust attenuation until the fourth corner power is equal to P1, and obtain the corresponding first amplitude control value; Open the first corner antenna channel 1 and the fourth corner antenna channel 13, close other antenna channels, fix the phase of the first corner antenna channel 1, adjust the phase of the fourth corner antenna channel 13, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the fourth corner antenna channel 13.

[0043] In this embodiment, the first corner antenna channel 1 is used as a reference antenna channel to calibrate the second corner antenna channel 4 , the third corner antenna channel 16 , and the fourth corner antenna channel 13 , respectively.

[0044] In other embodiments, antenna channel 4, antenna channel 16 or antenna channel 13 may also be used as a reference antenna channel to calibrate the other three corner antenna channels, and in other embodiments, the first corner antenna channel, the second corner antenna channel, the third corner antenna channel, and the fourth corner antenna channel may also be interchangeable.

[0045] Specifically, refer to Figure 5 As shown, when performing the first calibration in the x-axis mirror unit of the second annular region, the following steps are included: Open the first x-axis antenna channel 2, close other antenna channels, set power attenuation, transmit the signal and measure the first x-axis power P2 obtained by the receiving antenna; Open the second x-axis antenna channel 3, close other antenna channels, transmit signals and adjust attenuation until the second x-axis power obtained by the receiving antenna is equal to P2, and obtain the corresponding first amplitude control value; Open the first x-axis antenna channel 2 and the second x-axis antenna channel 3, close other antenna channels, fix the phase of the first x-axis antenna channel, adjust the phase of the second x-axis antenna channel, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the second x-axis antenna channel 3.

[0046] Continue to open the third x-axis antenna channel 15, close other antenna channels, transmit signals and adjust attenuation until the third x-axis power is equal to P2, and obtain the corresponding first amplitude control value; Open the first x-axis antenna channel 2 and the third x-axis antenna channel 15, close other antenna channels, fix the phase of the first x-axis antenna channel 2, adjust the phase of the third x-axis antenna channel 15, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the third x-axis antenna channel 15.

[0047] Continue to open the fourth x-axis antenna channel 14, close other antenna channels, transmit signals and adjust attenuation until the fourth x-axis power is equal to P2, and obtain the corresponding first amplitude control value; Open the first x-axis antenna channel 2 and the fourth x-axis antenna channel 14, close other antenna channels, fix the phase of the first x-axis antenna channel 2, adjust the phase of the fourth x-axis antenna channel 14, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the fourth x-axis antenna channel 14.

[0048] In this embodiment, the first x-axis antenna channel 2 is used as a reference antenna channel to calibrate the second x-axis antenna channel 3 , the third x-axis antenna channel 15 , and the fourth x-axis antenna channel 14 , respectively.

[0049] In other embodiments, the second x-axis antenna channel 3, the third x-axis antenna channel 15, and the fourth x-axis antenna channel 14 may also be used as reference antenna channels to calibrate the other three x-axis antenna channels, and in other embodiments, the first x-axis antenna channel, the second x-axis antenna channel, the third x-axis antenna channel, and the fourth x-axis antenna channel may also be interchangeable.

[0050] Specifically, refer to Figure 6 As shown, when performing the first calibration in the y-axis mirror unit of the second annular region, the following steps are included: Open the first y-axis antenna channel 5, close other antenna channels, set power attenuation, transmit the signal and receive the measured first y-axis power P3 obtained by the antenna; Open the second y-axis antenna channel 8, close other antenna channels, transmit signals and adjust attenuation until the second x-axis power obtained by the receiving antenna is equal to P3, and obtain the corresponding first amplitude control value; Open the first y-axis antenna channel 5 and the second y-axis antenna channel 8, close other antenna channels, fix the phase of the first y-axis antenna channel, adjust the phase of the second y-axis antenna channel, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the second y-axis antenna channel.

[0051] Continue to open the third y-axis antenna channel 12, close other antenna channels, transmit signals and adjust attenuation until the third y-axis power is equal to P3, and obtain the corresponding first amplitude control value; Open the first y-axis antenna channel 5 and the third y-axis antenna channel 12, close other antenna channels, fix the phase of the first y-axis antenna channel 5, adjust the phase of the third y-axis antenna channel 12, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the third y-axis antenna channel 12.

[0052] Continue to open the fourth y-axis antenna channel 9, close other antenna channels, transmit signals and adjust attenuation until the fourth x-axis power is equal to P3, and obtain the corresponding first amplitude control value; Open the first y-axis antenna channel 5 and the fourth y-axis antenna channel 9, close other antenna channels, fix the phase of the first y-axis antenna channel 5, adjust the phase of the fourth y-axis antenna channel 9, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the fourth y-axis antenna channel 9.

[0053] In this embodiment, the first y-axis antenna channel 5 is used as a reference antenna channel to calibrate the second y-axis antenna channel 8 , the third y-axis antenna channel 12 , and the fourth y-axis antenna channel 9 , respectively.

[0054] In other embodiments, the second y-axis antenna channel 8, the third y-axis antenna channel 12, and the fourth y-axis antenna channel 9 may also be used as reference antenna channels to calibrate the other three y-axis antenna channels, and in other embodiments, the first y-axis antenna channel, the second y-axis antenna channel, the third y-axis antenna channel, and the fourth y-axis antenna channel may also be interchangeable.

[0055] Specifically, refer to Figure 7 As shown, when performing the first calibration in the first annular area corner unit, the following steps are included: Open the first corner antenna channel 6, close other antenna channels, set power attenuation, transmit the signal and measure the first corner power P4 obtained by the receiving antenna; Open the second corner antenna channel 7, close other antenna channels, transmit signals and adjust attenuation until the second corner power obtained by the receiving antenna is equal to P4, and obtain the corresponding first amplitude control value; Open the first corner antenna channel 6 and the second corner antenna channel 7, close other antenna channels, fix the phase of the first corner antenna channel 6, adjust the phase of the second corner antenna channel 7, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the second corner antenna channel 7.

[0056] Continue to open the third corner antenna channel 11, close other antenna channels, transmit signals and adjust attenuation until the third corner power is equal to P4, and obtain the corresponding first amplitude control value; Open the first corner antenna channel 6 and the third corner antenna channel 11, close other antenna channels, fix the phase of the first corner antenna channel 6, adjust the phase of the third corner antenna channel 11, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the third corner antenna channel 11.

[0057] Continue to open the fourth corner antenna channel 10, close other antenna channels, transmit signals and adjust attenuation until the fourth corner power is equal to P4, and obtain the corresponding first amplitude control value; Open the first corner antenna channel 6 and the fourth corner antenna channel 10, close other antenna channels, fix the phase of the first corner antenna channel 6, adjust the phase of the fourth corner antenna channel 10, record the first phase control values ​​of the two channels when the power is maximum, and complete the calibration of the fourth corner antenna channel 10.

[0058] In this embodiment, the first corner antenna channel 6 in the first annular area is used as a reference antenna channel to calibrate the second corner antenna channel 7 , the third corner antenna channel 11 , and the fourth corner antenna channel 10 , respectively.

[0059] In other embodiments, antenna channel 7, antenna channel 11 or antenna channel 10 may also be used as a reference antenna channel to calibrate the other three corner antenna channels, and in other embodiments, the first corner antenna channel, the second corner antenna channel, the third corner antenna channel, and the fourth corner antenna channel may also be interchangeable.

[0060] Furthermore, in the method, when performing the second calibration between the plurality of subunits of the second annular region Ring2, the following steps are included: Open all antenna channels corresponding to the corner units in the second annular area after calibration, close other antenna channels, and use a spectrum analyzer to measure the sub-unit power P5 obtained by the receiving antenna; Close all antenna channels corresponding to the corner units in the second annular area, open all antenna channels corresponding to the x-axis mirror units in the second annular area after calibration, and synchronously control the amplitude attenuation control of all corresponding antenna channels until the measured value of the spectrum analyzer is a 1 *P5, factor , D is the phase center distance from the receiving antenna to the phased array antenna, d 2 is the distance from the phase center of the x-axis mirror unit to the phase center of the phased array antenna; d 1 The second amplitude control value corresponding to the distance from the phase center of the corner unit to the phase center of the phased array antenna is obtained; Synchronously open all antenna channels corresponding to the second annular area corner unit and the second annular area x-axis mirror unit, keep the amplitude and phase of all antenna channels of the second annular area corner unit unchanged, synchronously change the phase of all antenna channels of the second annular area x-axis mirror unit, record the second phase control value of the two channels when the power is maximum, and complete the calibration of the x-axis mirror unit of the second annular area.

[0061] In this embodiment, the second annular area corner unit is used as a reference unit to calibrate the second annular area x-axis mirror unit. In other embodiments, any sub-unit of the same annular area can be selected as a reference unit to calibrate other sub-units.

[0062] Furthermore, in the method, when performing the third calibration between different annular areas, the following steps are included: Open all antenna channels of the calibrated corner unit in the first annular area, close other antenna channels, and use a spectrum analyzer to measure the power P6 of the first corner unit obtained by the receiving antenna; Close all antenna channels of the corner units in the first annular area, open all antenna channels of the corner units in the second annular area after calibration, and synchronously control the amplitude attenuation control of all corresponding antenna channels until the measured value of the spectrum analyzer is a 3 *P6, factor , D is the phase center distance from the receiving antenna to the phased array antenna, d 4 is the distance from the phase center of the corner unit of the second annular region to the phase center of the phased array antenna; d 1 Obtain a corresponding third amplitude control value for the distance from the phase center of the corner unit of the first annular area to the phase center of the phased array antenna; Synchronously open all antenna channels corresponding to the above two corner units, keep the amplitude and phase of all antenna channels of the first annular area corner unit unchanged, synchronously change the phase of all antenna channels of the second annular area corner unit, record the third phase control value of the two channels when the power is maximum, and complete the calibration.

[0063] In this embodiment, the first annular area corner unit is used as a reference unit to calibrate the second annular area corner unit, so that the first annular area is used to calibrate the second annular area. In other embodiments, any one of the different annular areas can be selected as a reference unit to calibrate the other annular areas.

[0064] Finally, the first amplitude control value, the second amplitude control value, and the third amplitude control value of each antenna channel are added to obtain a final amplitude control value, and the first phase control value, the second phase control value, and the third phase control value of each antenna channel are added to obtain a final phase control value, thereby realizing the transmission calibration of the entire phased array antenna.

[0065] In this embodiment, the logical basis of the calibration process is to ensure that the path phase difference of the antenna units at geometrically symmetrical positions is zero when receiving signals. This means that when signals arrive at the receiving antenna units from different antenna channels of the phased array antenna, their arrival time is consistent, thereby ensuring phase consistency. In addition, the phase center of each geometrically symmetrical sub-unit should coincide with the physical center of the entire phased array antenna. Such a design can ensure that the propagation path and phase difference of the signal in each sub-unit are accurately controlled and coordinated, so that the performance of the entire antenna system is optimized.

[0066] Further, if Figure 3As shown in the figure, when multiple signals of the same frequency are superimposed in the antenna system, the amplitude of the composite signal will show periodic changes as the phase difference changes. This periodic change is due to the interference effect caused by the phase difference between different signals. By accurately controlling and adjusting the phase difference of each antenna unit, the amplitude of the composite signal can be accurately controlled, thereby improving the reception quality and transmission efficiency of the signal. This calibration method is not only suitable for signal processing in static environments, but also for dynamically changing communication scenarios, ensuring the stability and reliability of the antenna system under various conditions.

[0067] In the process of implementing the above calibration method, it is also necessary to consider the impact of environmental factors on signal propagation. For example, temperature changes, humidity changes, and wind speed will affect the propagation path and phase of the signal. Therefore, in actual operation, it is necessary to monitor these environmental factors in real time and dynamically adjust the calibration parameters based on the monitoring results.

[0068] To achieve this goal, an environmental monitoring module can be introduced, which can monitor environmental parameters in real time and transmit data to the control system. The control system automatically adjusts the calibration parameters according to the changes in environmental parameters to ensure the accuracy of the calibration process. For example, when the temperature rises and the signal propagation speed changes, the control system will adjust the phase control parameters accordingly to compensate for the impact of temperature changes on the signal propagation path.

[0069] In addition, in order to further improve the accuracy of calibration, a multi-frequency calibration method can be used. Calibration at different frequency points can ensure the phase consistency of the signal in the entire working frequency band. In specific operations, the above calibration process can be repeated at multiple predetermined frequency points, and the amplitude attenuation control and relative phase control parameters at each frequency point can be recorded. Then, through interpolation or fitting methods, a calibration parameter curve in the entire frequency band can be generated, thereby achieving accurate calibration of any frequency point.

[0070] In one embodiment, an electronic device is also provided, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the memory is coupled to the processor, and when the processor executes the computer program, the phased array antenna transmission calibration method for the built-in local oscillator described in the first aspect is implemented.

[0071] In summary, the calibration logic design adopted by the present invention is extremely concise and clear, ensuring that the receiving antenna does not need to perform any movement operation when executing the calibration procedure. This design significantly improves the efficiency of the calibration operation, making the entire process more efficient and convenient, especially for phased array systems with integrated local oscillators.

[0072] The calibration technology of the present invention is not only applicable to phased array systems with integrated local oscillators, but can also be widely used in the calibration of various highly integrated active phased array radars (AIP phased arrays). Therefore, the present invention has broad application prospects and practical application value in the field of radar system calibration.

[0073] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calibrating the transmission of a phased array antenna with a built-in local oscillator, characterized in that: The following steps are involved: Build and configure the test system, where the receiving antenna is located on the central axis of the phased array antenna, and the receiving antenna is connected to the spectrum analyzer; The phased array antenna is divided according to its layout, and is divided into a plurality of centrosymmetric annular regions according to the central axis of the phased array antenna, and each annular region has one or more centrosymmetric subunits, and each subunit includes a plurality of antenna channels of the same number; The phased array antenna is used to transmit signals and the receiving antenna is used to receive signals. Amplitude and phase calibration is performed between antenna channels within the subunits of the annular area, between subunits of the annular area, and between different annular areas, respectively, to achieve transmission calibration of the entire phased array antenna.

2. The method for calibrating the transmission of a phased array antenna with a built-in local oscillator according to claim 1, characterized in that: The test system includes a phased array antenna, a receiving antenna, a spectrum analyzer and a control computer. The receiving antenna is connected to a signal generator. One end of the control computer is connected to the phased array antenna for configuring and controlling different antenna channels of the phased array antenna to transmit signals. The other end of the control computer is connected to the signal generator for obtaining the amplitude and phase signals corresponding to the receiving antenna.

3. The method for calibrating the transmission of a phased array antenna with a built-in local oscillator according to claim 1, characterized in that: The annular area has multiple centrally symmetrical sub-units, which specifically include corner units, x-axis mirror units and y-axis mirror units. The corner units are multiple antenna channels located at the four corners of the annular area, the x-axis mirror units are multiple antenna channels located in the x-axis direction of the annular area and are centrally symmetrical, and the y-axis mirror units are multiple antenna channels located in the y-axis direction of the annular area and are centrally symmetrical.

4. The method for calibrating the transmission of a phased array antenna with a built-in local oscillator according to claim 3, characterized in that: In the method, first calibration is performed in the corner unit, the x-axis mirror unit, and the y-axis mirror unit respectively to obtain a first amplitude control value and a first phase control value of the corresponding antenna channel; a second calibration is performed between sub-units in the same annular area to obtain a second amplitude control value and a second phase control value of the corresponding antenna channel; a third calibration is performed between different annular areas to obtain a third amplitude control value and a third phase control value of the corresponding antenna channel; the first amplitude control value, the second amplitude control value, and the third amplitude control value are added to obtain a final amplitude control value, and the first phase control value, the second phase control value, and the third phase control value are added to obtain a final phase control value, thereby realizing the transmission calibration of the entire phased array antenna.

5. The method for calibrating the transmission of a phased array antenna with a built-in local oscillator according to claim 3, characterized in that: In the method, when performing the first calibration in the corner unit, the following steps are included: Open the first corner antenna channel, close other antenna channels, set a specific power attenuation, transmit the signal and measure the first corner power P1 of the receiving antenna; Open the second corner antenna channel, close other antenna channels, transmit signals and adjust attenuation until the second corner power of the receiving antenna is equal to P1, and obtain the first amplitude control value corresponding to the second corner antenna channel; Open the first corner antenna channel and the second corner antenna channel, close other antenna channels, fix the phase of the first corner antenna channel, adjust the phase of the second corner antenna channel, record the first phase control values ​​corresponding to the two antenna channels when the power is maximum, and complete the first calibration of the second corner antenna channel; The first corner antenna channel and other corner antenna channels in the corner unit are opened in sequence and simultaneously, and the above steps are repeated to complete the first calibration of other corner antenna channels.

6. The method for calibrating the transmission of a phased array antenna with a built-in local oscillator according to claim 3, characterized in that: In the method, when performing the first calibration in the x-axis mirror unit, the following steps are included: Open the first x-axis antenna channel, close other antenna channels, set a specific power attenuation, transmit a signal and measure the first x-axis power P2 of the receiving antenna; Open the second x-axis antenna channel, close other antenna channels, transmit signals and adjust attenuation until the second x-axis power of the receiving antenna is equal to P2, and obtain the first amplitude control value corresponding to the second x-axis antenna channel; Open the first x-axis antenna channel and the second x-axis antenna channel, close other antenna channels, fix the phase of the first x-axis antenna channel, adjust the phase of the second x-axis antenna channel, record the first phase control values ​​of the two antenna channels when the power is maximum, and complete the first calibration of the second x-axis antenna channel; The first x-axis antenna channel and other x-axis antenna channels in the x-axis mirror unit are opened in sequence and simultaneously, and the above steps are repeated to complete the first calibration of other x-axis antenna channels.

7. The method for calibrating the transmission of a phased array antenna with a built-in local oscillator according to claim 3, characterized in that: In the method, when performing the first calibration in the y-axis mirror unit, the following steps are included: Open the first y-axis antenna channel, close other antenna channels, set a specific power attenuation, transmit a signal and measure the first y-axis power P3 of the receiving antenna; Open the second y-axis antenna channel, close other antenna channels, transmit signals and adjust attenuation until the second y-axis power of the receiving antenna is equal to P3, and obtain the first amplitude control value corresponding to the second y-axis antenna channel; Open the first y-axis antenna channel and the second y-axis antenna channel, close other antenna channels, fix the phase of the first y-axis antenna channel, adjust the phase of the second y-axis antenna channel, record the first phase control values ​​of the two antenna channels when the power is maximum, and complete the first calibration of the second y-axis antenna channel; The first y-axis antenna channel and other y-axis antenna channels in the y-axis mirror unit are opened in sequence and simultaneously, and the above steps are repeated to complete the first calibration of other y-axis antenna channels.

8. The method for calibrating the transmission of a phased array antenna with a built-in local oscillator according to claim 3, characterized in that: In the method, when performing the second calibration between subunits in the same annular area, the following steps are included: Open all antenna channels corresponding to a calibrated sub-unit in the same annular area, close other antenna channels, transmit signals and measure the sub-unit power P5 of the receiving antenna using a spectrum analyzer; Close all antenna channels corresponding to a subunit in the same annular area, open all antenna channels corresponding to any one of the other calibrated subunits, and synchronously control the amplitude attenuation control of all corresponding antenna channels until the measured value of the spectrum analyzer is a1*P5, the factor , D is the phase center distance from the receiving antenna to the phase array antenna, d2 is the phase center distance from the phase center in the other subunits to the phase center of the phase array antenna; d1 is the phase center distance from a subunit in the same annular area to the phase center of the phase array antenna, and the corresponding second amplitude control value is obtained; Synchronously open all antenna channels corresponding to the subunits that have completed amplitude calibration, keep the amplitude and phase of all antenna channels of one of the subunits unchanged, synchronously change the phase of all antenna channels of another subunit, record the second phase control value of the other subunit when the power is maximum, and complete the calibration of another subunit in the same annular area; All antenna channels corresponding to a subunit in the same annular area and all antenna channels corresponding to another subunit in the same annular area are opened in sequence and simultaneously, and the above steps are repeated to complete the second calibration of all subunits in the same annular area.

9. The method for calibrating the transmission of a phased array antenna with a built-in local oscillator according to claim 3, characterized in that: In the method, when performing the third calibration between different annular areas, the following steps are included: Open all antenna channels of a subunit in the first annular area after calibration, close other antenna channels, transmit signals and measure the power P6 of a subunit in the first annular area obtained by the receiving antenna using a spectrum analyzer; Close all antenna channels of a subunit in the first annular area, open all antenna channels of a subunit in a different annular area after calibration, and synchronously control the amplitude attenuation control of all corresponding antenna channels until the measured value of the spectrum analyzer is a3*P6, factor , D is the phase center distance from the receiving antenna to the phase array antenna, d4 is the phase center distance from the phase center of a subunit corresponding to different annular areas to the phase center distance of the phase array antenna; d1 is the phase center distance from the phase center of a subunit corresponding to the first annular area to the phase center distance of the phase array antenna, and a third amplitude control value of a subunit corresponding to a different annular area is obtained; Synchronously open all antenna channels after the amplitude calibration is completed, keep the amplitude and phase of all antenna channels of a subunit of the first annular area unchanged, synchronously change the phase of all antenna channels of a subunit of different annular areas, record the third phase control value of a subunit corresponding to different annular areas when the power is maximum, and complete the third calibration corresponding to different annular areas; All antenna channels corresponding to a subunit of the first annular area and all antenna channels corresponding to a subunit of other annular areas are opened in sequence and simultaneously, and the above steps are repeated to complete the third calibration of all annular areas.

10. The method for calibrating the transmission of a phased array antenna with a built-in local oscillator according to claim 1, characterized in that: The phase centers of the centrally symmetric sub-units coincide with the physical center of the phased array antenna.

11. The method for calibrating the transmission of a phased array antenna with a built-in local oscillator according to claim 1, characterized in that: Also includes: The multi-frequency calibration method is adopted to perform multiple calibrations at different frequency points.

12. An electronic device, characterized in that: The method comprises a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the memory is coupled to the processor, and when the processor executes the computer program, the phased array antenna transmission calibration method according to any one of claims 1 to 11 is implemented.

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