Sub-array extended phased-array antenna and control method, device and system thereof

Abstract

The invention provides a sub-array expansion phased-array antenna and a control method, device and system thereof, and relates to the technical field of phased-array antennas. According to the invention, a plurality of pre-calibrated sub-arrays are expanded to construct the phased-array antenna. And performing intra-array phase shift calibration based on an intra-array phase shifter in each sub-array, so that each antenna signal phase in the array is synchronized. And performing out-of-array phase shift calibration on the in-array phase synchronization signal through an out-of-array phase shifter based on the relative position relationship of the sub-arrays and the target beam direction, so that the phases of the signals output among the sub-arrays are synchronized, and the phase calibration of the phased-array antenna is realized. According to the embodiment of the invention, the out-of-array phase calibration is carried out outside the pre-calibrated sub-array, and each antenna in the expanded sub-array does not need to be adjusted, so that each antenna of each sub-array is prevented from being calibrated, and the expansion efficiency of the sub-array is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of phased array antennas, and in particular, to a sub-array expanded phased array antenna, a control method, a device and a system thereof. Background Art

[0002] A phased array antenna is an antenna system composed of multiple antennas arranged according to a certain rule. By controlling the amplitude and phase of the signals emitted by each antenna, the shape of the antenna pattern, the beam pointing and the beam width and other characteristics are changed, so as to realize the directional radiation and reception of electromagnetic waves. A sub-array of a phased array antenna refers to a smaller array unit formed by combining multiple antenna elements in the phased array antenna according to a certain rule. Arranging and connecting multiple sub-arrays in one-dimensional or multi-dimensional directions, such as splicing one by one in the horizontal direction or the vertical direction, can quickly expand and increase the aperture size of the antenna in this direction, and improve the antenna gain and resolution.

[0003] For a phased array antenna formed by sub-array expansion, all antennas need to be re-phase calibrated. The goal of phase calibration is to make all antenna elements of the phased array antenna in an equiphase plane. Only when the phases of all antenna elements are synchronized can it be ensured that the electromagnetic waves synthesized in space are in-phase superposed in a specific direction to form the required beam shape and pointing. However, the calibration of the phased array is highly complex. Each time during the design of the phased array surface, it is necessary to ensure the phase synchronization of all antenna channels in the whole array. After the design of the phased array surface is completed, when the sub-array is expanded later, it is necessary to re-phase calibrate all antenna channels again, resulting in low calibration efficiency when the phased array antenna expands the sub-array. Summary of the Invention

[0004] Embodiments of the present invention provide a sub-array expanded phased array antenna, a control method, a device and a system thereof, so as to solve the problem of low calibration efficiency of existing phased array antennas.

[0005] In a first aspect, an embodiment of the present invention provides a sub-array expanded phased array antenna, including: a plurality of pre-calibrated sub-arrays; each sub-array is connected with an out-of-array phase shifter;

[0006] The sub-array includes a plurality of array antennas, and each array antenna is connected with an in-array phase shifter;

[0007] For any sub-array, each in-array phase shifter is used to perform phase shift calibration on the corresponding array antenna based on pre-calibrated parameters, so that the output signal phases of the array antennas in the array are synchronized;

[0008] The out-of-array phase shifter of any sub-array is used to determine the phase difference of the sub-array according to the relative position difference between the sub-array and other sub-arrays and the target beam pointing, and perform re-phase shift calibration on the signals with synchronized phases in the sub-array according to the phase difference, so that the output signal phases between the sub-arrays are synchronized.

[0009] In a possible implementation, for any out-of-array phase shifter, an out-of-array attenuator connected in series with the out-of-array phase shifter is further included; the out-of-array attenuator is used to compensate for the amplitude difference between sub-arrays.

[0010] In a possible implementation, a combining network is further included; one side of the combining network is connected to the out-of-array phase shifters of each sub-array, and the other side outputs or outputs a radio frequency combined signal.

[0011] In a second aspect, an embodiment of the present invention provides a control method for a sub-array extended phased array antenna, which is applied to any sub-array extended phased array antenna in the first aspect; the method includes:

[0012] Obtain the target beam direction of the phased array antenna; the target beam direction includes the elevation angle and the azimuth angle;

[0013] Based on the target beam direction and pre-calibrated parameters, determine the phase shift value of the phase shifter corresponding to each array antenna of each sub-array, and control the phase shift calibration based on the phase shift value to synchronize the phases of the output signals of the array antennas within the sub-array;

[0014] Based on the target beam direction and the relative position differences between sub-arrays, determine the phase difference of each sub-array;

[0015] Use the phase difference of the sub-array as the phase shift value, and control the out-of-array phase shifter to perform phase shift calibration again on the signals with synchronized phases within the sub-array outside the sub-array, so as to synchronize the phases of the signals output between the sub-arrays of the phased array antenna.

[0016] In a possible implementation, the determining the phase shift value of the phase shifter corresponding to each array antenna of each sub-array based on the target beam direction and pre-calibrated parameters includes:

[0017] Determine the phase shift value based on the following formula:

[0018]

[0019] where φ ij represents the phase shift value of the jth array antenna of the ith sub-array, y ij represents the y-axis coordinate of the jth antenna of the ith sub-array, z ij represents the z-axis coordinate of the jth antenna of the ith sub-array, θ 0 represents the elevation angle, φ 0 represents the azimuth angle, and λ represents the operating wavelength.

[0020] In a possible implementation, the determining the phase difference of each sub-array based on the target beam direction and the relative position differences between sub-arrays includes:

[0021] For any sub-array, determine the relative position difference between this sub-array and the first sub-array;

[0022] Based on the target beam pointing and the relative position difference between this sub-array and the first sub-array, determine the phase difference of this sub-array.

[0023] In a possible implementation manner, the determining the relative position difference between any sub-array and the first sub-array includes:

[0024] For the j-th array antenna of any sub-array, obtain the relative position difference between this array antenna and the j-th array antenna in the first sub-array;

[0025] Correspondingly, based on the target beam pointing and the relative position difference between this sub-array and the first sub-array, determining the phase difference of this sub-array includes:

[0026] Based on the target beam pointing and the relative position difference between the j-th array antenna of this sub-array and the j-th array antenna in the first sub-array, determine the phase difference of this sub-array.

[0027] In a possible implementation manner, the based on the target beam pointing and the relative position difference between the j-th array antenna of this sub-array and the j-th array antenna in the first sub-array, determining the phase difference of this sub-array includes:

[0028] Determine the phase difference based on the following formula:

[0029]

[0030] where, Δφ′ ij represents the phase difference between the j-th array antenna of the i-th sub-array and the j-th array antenna of the first sub-array; y 1j represents the y-axis coordinate of the j-th antenna of the first sub-array; z 1j represents the z-axis coordinate of the j-th antenna of the first sub-array.

[0031] In a third aspect, an embodiment of the present invention provides a control device for a sub-array extended phased array antenna, and the device includes:

[0032] An acquisition module, configured to acquire the target beam pointing of the phased array antenna; the target beam pointing includes an elevation angle and an azimuth angle;

[0033] A first calibration module, configured to determine the phase shift value of the phase shifter corresponding to each array antenna of each sub-array based on the target beam pointing and pre-calibrated parameters, and control phase shift calibration based on the phase shift value, so that the output signal phases of the array antennas in this sub-array are synchronized;

[0034] A phase difference determination module, configured to determine the phase difference of each sub-array based on the target beam direction and the relative position difference between sub-arrays;

[0035] A second calibration module, configured to use the phase difference of the sub-array as a phase shift value to control an out-of-array phase shifter to perform phase shift calibration again on the signals with in-array phase synchronization within the sub-array outside the sub-array, so as to achieve signal phase synchronization of outputs between sub-arrays of the phased array antenna.

[0036] In a fourth aspect, an embodiment of the present invention provides a control system for a sub-array extended phased array antenna, including the sub-array extended phased array antenna as described in any one of the first aspects.

[0037] Embodiments of the present invention provide a sub-array extended phased array antenna, its control method, device, and system. The present invention constructs a phased array antenna by extending multiple pre-calibrated sub-arrays. Intra-array phase shift calibration is performed based on the intra-array phase shifters within each sub-array to synchronize the phase of each antenna signal within the array. And an out-of-array phase shifter performs out-of-array phase shift calibration on the in-array phase synchronized signals based on the relative position relationship between sub-arrays and the target beam direction, so as to synchronize the phase of the signals output between sub-arrays, realizing the phase calibration of the phased array antenna. Embodiments of the present invention perform out-of-array phase calibration outside the pre-calibrated sub-arrays, without adjusting each antenna inside the extended sub-arrays, avoiding calibrating each antenna of each sub-array, and improving the extension efficiency of the sub-arrays. Description of the Drawings

[0038] Figure 1 It is a schematic diagram of the sub-array layout structure of a phased array antenna provided by an embodiment of the present invention;

[0039] Figure 2 It is a schematic circuit diagram of a sub-array extended phased array antenna provided by an embodiment of the present invention;

[0040] Figure 3 It is a schematic circuit diagram of a sub-array provided by an embodiment of the present invention;

[0041] Figure 4 It is a schematic diagram of the connection relationship of control ports between sub-arrays provided by an embodiment of the present invention;

[0042] Figure 5 It is a schematic circuit diagram of the combining network 1 provided by an embodiment of the present invention;

[0043] Figure 6 It is a schematic circuit diagram of the combining network 2 provided by an embodiment of the present invention. Detailed Embodiments

[0044] To enable those skilled in the art to better understand this solution, the following will clearly describe the technical solution in the embodiments of this solution in conjunction with the accompanying drawings in the embodiments of this solution. Obviously, the described embodiments are part of the embodiments of this solution, rather than all of the embodiments. Based on the embodiments in this solution, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this solution.

[0045] The terms "including" and any other variations in the description and claims of this solution and the above-mentioned accompanying drawings mean "including but not limited to", intending to cover non-exclusive inclusion and not limited to the examples listed in the text. In addition, terms such as "first" and "second" are used to distinguish different objects, rather than to describe a specific order.

[0046] The following will describe the implementation of the present invention in detail in conjunction with specific accompanying drawings:

[0047] The complex environment and threats from the target require that the phased array system must have the capabilities of long-distance detection and precise tracking, which means that the phased array antenna needs to have high gain and large physical aperture. The modular design concept is based on a set of hardware architecture solutions, adopting hardware configurations and architectures suitable for the installation conditions of different platforms, reducing the complexity of system development and shortening the development cycle. Due to the serialization and generalization of active subarrays, the maintainability is improved, and the construction cost of the system is also significantly reduced.

[0048] Since the development of each type of phased array antenna alone has high development complexity, long development cycle, and poor development inheritance, the subarray expansion method can conveniently and flexibly construct the phased array antenna.

[0049] The embodiment of the present invention avoids adjusting each antenna within the subarray by means of out-of-subarray phase calibration outside the subarray, improving the calibration efficiency of the expanded subarray of the phased array antenna and the expansion efficiency of the phased array antenna.

[0050] Figure 1 This is a schematic diagram of the subarray layout structure of a phased array antenna provided by an embodiment of the present invention. Referring to Figure 1 , exemplarily, the phased array antenna includes 8 subarrays. The subarrays are arranged in 4 rows and 2 columns.

[0051] The structures of the subarrays are the same. Exemplarily, each subarray includes 32 antenna elements. The antenna elements are arranged in 4 rows and 8 columns. Each antenna element corresponds to one channel, and this phased array antenna is a 256-channel antenna.

[0052] Exemplarily, the phased array antenna is a planar phased array antenna. The radiation units of the planar phased array antenna are usually distributed in a two-dimensional plane.

[0053] Figure 2 This is a circuit schematic diagram of a sub-array extended phased array antenna provided by an embodiment of the present invention. Refer to Figure 2 , an embodiment of the present invention provides a sub-array extended phased array antenna, including: a plurality of pre-calibrated sub-arrays; each sub-array is connected to an out-of-array phase shifter; the sub-array includes a plurality of array antennas, and each array antenna is connected to an in-array phase shifter; for any sub-array, each in-array phase shifter is used to perform phase shift calibration on the corresponding array antenna based on pre-calibrated parameters, so that the output signal phases of the array antennas within the array are synchronized; the out-of-array phase shifter of any sub-array is used to determine the phase difference of the sub-array according to the relative position difference between the sub-array and other sub-arrays and the target beam pointing, and perform re-phase shift calibration on the signals with synchronized phases within the sub-array according to the phase difference, so that the output signal phases between the sub-arrays are synchronized.

[0054] It should be noted that the sub-array extended phased array antenna means that the phased array antenna provided by the embodiment of the present invention is assembled by extending a plurality of sub-arrays.

[0055] In some embodiments, the sub-array extended phased array antenna includes a plurality of pre-calibrated sub-arrays. It should be noted that the sub-arrays are pre-calibrated at the factory to facilitate subsequent assembly into phased array antennas of various models. For example, according to actual requirements, 8 sub-arrays may be assembled into a phased array antenna with a 2*4 layout, or may be assembled into a 1*8 phased array antenna. For another example, on the basis of the assembled phased array antenna, sub-arrays may be continuously extended and added, such as extending the 2*4 layout to a 2*5 layout. Exemplarily, the sub-array is a pre-phase calibrated sub-array. For the sub-array after phase calibration, the output signals of the antennas inside it can achieve phase synchronization.

[0056] It should be noted that even though the antennas inside the sub-array can be phase synchronized, after a plurality of sub-arrays are assembled, the installation positions of the sub-arrays are different, and the phased array antenna as a whole is not phase synchronized. The purpose of setting the out-of-array phase shifter in the present invention is to make the phased array antenna as a whole phase synchronized. The following is an explanation.

[0057] In some embodiments, each sub-array is connected to an out-of-array phase shifter. The sub-array includes a plurality of array antennas, each array antenna is connected to an in-array phase shifter, and each in-array phase shifter is connected to the out-of-array phase shifter of the sub-array.

[0058] Here, the in-array phase shifter and the out-of-array phase shifter are defined relative to the inside and outside of the sub-array. Each sub-array is correspondingly provided with a plurality of in-array phase shifters and an out-of-array phase shifter.

[0059] Exemplarily, each sub-array further includes a power divider. Each in-array phase shifter of the sub-array is connected to the out-of-array phase shifter of the sub-array through the above-mentioned power divider. The power divider can combine multiple signals into one signal. For example, the power divider includes a plurality of shunt terminals and a combiner terminal. Each shunt terminal is connected to an in-array phase shifter, and the combiner terminal is connected to the out-of-array phase shifter of the sub-array.

[0060] The above has described the specific installation positions of the in-array / out-of-array phase shifters. The following will describe the specific functions of installing the in-array / out-of-array phase shifters.

[0061] In some embodiments, for any sub-array, each in-array phase shifter is used to perform phase shift calibration on the corresponding array antenna based on pre-calibrated parameters, so as to synchronize the output signal phases of the in-array array antennas;

[0062] It should be noted that in order to enhance the interference of the signals of two antennas in a certain spatial direction, the signals of the two antennas need to be phase-synchronized. Due to the different processes of each array antenna, the phase differences of the signals of the two antennas in a certain spatial direction are different. Exemplarily, during the pre-factory calibration of the sub-array, the phase differences of the antennas within the sub-array can be calibrated and stored in the memory within the sub-array. After receiving the instruction of the spatial direction, the controller within the sub-array can determine the phase differences of the antennas based on the pre-calibrated parameters. Further, the in-array phase shifters can be controlled to perform phase shift calibration on each antenna, so that the phases of the antennas tend to be consistent, that is, the output signal phases of the in-array array antennas are synchronized.

[0063] Further, in some embodiments, the out-of-array phase shifter of any sub-array is used to determine the phase difference of the sub-array according to the relative position difference between the sub-array and other sub-arrays and the target beam direction, and perform secondary phase shift calibration on the signals with synchronized phases within the sub-array according to the phase difference, so as to synchronize the output signal phases between the sub-arrays.

[0064] It should be noted that after the sub-arrays are extended and assembled, the relative position differences between the sub-arrays can be determined according to the specific layout of each sub-array. Thus, the phase difference of the sub-array can be determined according to the relative position difference between the sub-array and other sub-arrays. Further, the out-of-array phase shifter of the sub-array can be controlled to perform secondary phase shift on the signals of the sub-array according to the determined phase difference. By performing secondary phase shift calibration on the signals with synchronized phases output by each sub-array in the embodiments of the present invention, the output signal phases between the sub-arrays can be synchronized.

[0065] In the embodiment of the present invention, a phased array antenna is constructed by expanding multiple pre-calibrated sub-arrays. Intra-array phase shift calibration is performed based on the intra-array phase shifters inside each sub-array to synchronize the phase of each antenna signal inside the array. And an extra-array phase shifter is used to perform extra-array phase shift calibration on the intra-array phase synchronized signal based on the relative position relationship of each sub-array and the target beam direction, so as to synchronize the phase of the signals output between each sub-array, realizing the phase calibration of the phased array antenna. In the embodiment of the present invention, extra-array phase calibration is performed outside the pre-calibrated sub-array, and it is not necessary to adjust each antenna inside the expanded sub-array, avoiding calibrating each antenna of each sub-array, and improving the expansion efficiency of the sub-array.

[0066] In a possible implementation manner, for any extra-array phase shifter, an extra-array attenuator connected in series with the extra-array phase shifter is further included; the extra-array attenuator is used to compensate for the amplitude difference between each sub-array.

[0067] Exemplarily, the extra-array attenuator is arranged between the extra-array phase shifter and the sub-array. In another example, the extra-array phase shifter is arranged between the extra-array attenuator and the sub-array.

[0068] The extra-array attenuator in the embodiment of the present invention adjusts the signal amplitude, and pertinently attenuates the signal of the sub-array with a larger amplitude according to the actual amplitude difference between each sub-array, so that the amplitudes of the signals output by each sub-array can be as consistent as possible after being processed by the extra-array attenuator, thereby compensating for the amplitude difference between each sub-array.

[0069] In a possible implementation manner, a combining network is further included; one side of the combining network is connected to the extra-array phase shifters of each sub-array, and the other side outputs or outputs a radio frequency combined signal.

[0070] Exemplarily, the combining network includes a plurality of two-way splitters.

[0071] The following uses a comprehensive embodiment to illustrate the structure of the sub-array expanded phased array antenna. Refer to Figure 1 、 Figure 2 , n identical 32-channel sub-arrays (4×8) are expanded into an n×32-channel phased array, where n is any positive integer. For example, when n = 8, a (16×16) 256-channel phased array is formed based on the sub-array expansion. The expanded phased array includes sub-arrays, a combining network, and a total controller.

[0072] Figure 3 This is a schematic diagram of a sub-array circuit provided by an embodiment of the present invention. Refer to Figure 3Sub-array block diagram, with 32 channels arranged in a 4×8 pattern. Each channel uses one phase shifter-attenuator to achieve amplitude-phase control of the channel RF signal. This phase shifter-attenuator is named the in-array phase shifter-attenuator. Each sub-array includes one FPGA controller and one Flash memory. The amplitude-phase difference between channels within a single sub-array and the beam pointing data have been calibrated before leaving the factory, and the calibration data is stored in the Flash memory.

[0073] Figure 4 This is a schematic diagram of the connection relationship of control ports between sub-arrays provided by an embodiment of the present invention. Referring to Figure 4 , the sub-array FPGA obtains the current beam pointing requirement requested by the user through instruction communication with the full-array FPGA. Further, by retrieving the phase shift data and attenuation data stored internally in the Flash, it is transmitted to each phase shifter-attenuator through the SPI interface, thereby realizing the switching of the sub-array beam pointing.

[0074] To implement the sub-array expansion function, each sub-array is set with a separate address code. The full-array FPGA addresses the current sub-array through serial communication to utilize instructions to achieve the pointing control function. If there are too many expanded sub-arrays resulting in insufficient driving ability of the output IO ports of the full-array FPGA, an additional current driving circuit can be added to the output IO ports of the full-array FPGA to solve the problem.

[0075] The following describes the combining network. The combining network circuit can include two parts: combining network 1 and combining network 2. Combining network 1 can be a power divider with amplitude-phase control. Figure 5 This is a circuit schematic diagram of combining network 1 provided by an embodiment of the present invention. Among them, each branch of the power divider with amplitude-phase control contains one phase shifter-attenuator, which is used to compensate for the phase difference between different pointings between sub-arrays and the amplitude difference between sub-arrays. This phase shifter-attenuator chip integrates a serial-parallel conversion function and can achieve amplitude-phase control of the transceiver signal. The chip input signals include input data DATin, serial input enable signal CS, shift clock CLK, and latch signal LOAD. Figure 5 CS, CLK, and LOAD are omitted in

[0076] Combining network 2 can include a two-way power divider. Figure 6 This is a circuit schematic diagram of combining network 2 provided by an embodiment of the present invention.

[0077] Referring to Figure 1 and Figure 2, expanded from 8 sub-arrays to a full array, with 256 channels, channel arrangement of 16×16, including 8 sub-arrays, and a synthesis network 1 is connected to the backend of each sub-array. The phase shifter attenuator inside the synthesis network 1 is an out-of-array phase shifter attenuator. There are multiple layers of synthesis network 2 at the backend of the synthesis network 1. The total controller includes an FPGA controller and a Flash memory, which are used to control the phase shifter attenuator of the synthesis network and store the control data.

[0078] An embodiment of the present invention provides a control method for a sub-array expanded phased array antenna, which is applied to the sub-array expanded phased array antenna in any item of the first aspect; the method includes:

[0079] Step 1, obtain the target beam pointing of the phased array antenna; the target beam pointing includes the elevation angle and the azimuth angle;

[0080] In some embodiments, the target beam pointing can be provided by the upper computer. For example, the target beam pointing determined by the upper computer based on the user instruction.

[0081] Exemplarily, the elevation angle represents the angle between the beam and the horizontal plane. With the horizontal plane as the reference, upward is positive and downward is negative, and the range is generally -90° to 90°.

[0082] Exemplarily, the azimuth angle represents the pointing angle of the beam on the horizontal plane. With a specific reference direction (such as the due north direction) as the reference, the clockwise direction is positive, and the range is usually 0° to 360°.

[0083] Step 2, based on the target beam pointing and the pre-calibrated parameters, determine the phase shift value of the phase shifter corresponding to each array antenna of each sub-array, and control the phase shift calibration based on the phase shift value to synchronize the output signal phases of the array antennas within the sub-array;

[0084] In a possible implementation manner, for any array antenna of any sub-array one by one, based on the target beam pointing and the relative positions of the array antennas determined in advance, determine the phase shift value of the phase shifter corresponding to the array antenna, and control the phase shift calibration based on the phase shift value to synchronize the output signal phases of the array antennas within the sub-array.

[0085] In a possible implementation manner, the determining the phase shift value of the phase shifter corresponding to each array antenna of each sub-array based on the target beam pointing and the pre-calibrated parameters includes:

[0086] Determine the phase shift value based on the following formula:

[0087]

[0088] where, Φ ijrepresents the phase shift value of the j-th array antenna in the i-th subarray, y ij represents the y-axis coordinate of the j-th antenna in the i-th subarray, z ij represents the z-axis coordinate of the j-th antenna in the i-th subarray, θ 0 represents the elevation angle, φ 0 represents the azimuth angle, and λ represents the operating wavelength.

[0089] Step 3: Based on the target beam direction and the relative position differences between subarrays, determine the phase difference of each subarray;

[0090] In a possible implementation, the determining the phase difference of each subarray based on the target beam direction and the relative position differences between subarrays includes: For any subarray, determine the relative position difference between this subarray and the first subarray; Based on the target beam direction and the relative position difference between this subarray and the first subarray, determine the phase difference of this subarray.

[0091] In a possible implementation, the determining the relative position difference between this subarray and the first subarray for any subarray includes: For the j-th array antenna of any subarray, obtain the relative position difference between this array antenna and the j-th array antenna in the first subarray;

[0092] Correspondingly, the determining the phase difference of this subarray based on the target beam direction and the relative position difference between this subarray and the first subarray includes: Based on the target beam direction and the relative position difference between the j-th array antenna of this subarray and the j-th array antenna in the first subarray, determine the phase difference of this subarray.

[0093] In a possible implementation, the determining the phase difference of this subarray based on the target beam direction and the relative position difference between the j-th array antenna of this subarray and the j-th array antenna in the first subarray includes: Determine the phase difference based on the following formula:

[0094]

[0095] where, Δφ′ ij represents the phase difference between the j-th array antenna in the i-th subarray and the j-th array antenna in the 1st subarray; y 1j represents the y-axis coordinate of the j-th antenna in the first subarray; z 1j represents the z-axis coordinate of the j-th antenna in the first subarray.

[0096] It should be noted that due to the periodicity of the array, the distances between antennas at the same intra-array position in two subarrays are the same. Therefore, j on the right side of the above formula can choose the number of any antenna, for example, j = 1. And no matter which antenna on the right side of the equation is selected as the reference, the phase difference obtained is theoretically the same.

[0097] Step 4: Use the phase difference of the subarray as the phase shift value to control the out-of-array phase shifter to perform out-of-array phase calibration on the signals with in-array phase synchronization within the subarray, so as to achieve signal phase synchronization among the subarrays of the phased array antenna.

[0098] The present invention constructs a phased array antenna by expanding multiple pre-calibrated subarrays. Based on the in-array phase shifters within each subarray, in-array phase calibration is performed to synchronize the phase of each antenna signal within the array. And based on the relative position relationship of each subarray and the target beam direction, the out-of-array phase shifter performs out-of-array phase calibration on the in-array phase synchronized signals, so that the signals output among the subarrays are phase synchronized, realizing the phase calibration of the phased array antenna. In the embodiment of the present invention, by performing out-of-array phase calibration outside the pre-calibrated subarray, it is not necessary to adjust each antenna inside the expanded subarray, avoiding calibrating each antenna of each subarray, and improving the expansion efficiency of the subarray.

[0099] The following uses a comprehensive embodiment to illustrate the above control method.

[0100] In some embodiments, the user issues a beam direction instruction, and the instruction is sent by the full-array FPGA to each subarray and each synthesis network. The following describes the full-array beamforming process

[0101] For a general n×32-channel planar phased array, when the beam points to the spatial direction (θ 0 , φ 0 ), (θ 0 is the elevation angle of the beam direction, φ 0 is the azimuth angle of the beam direction), the phase shifter value of the i-th channel is:

[0102]

[0103] where i = 1, 2, … m, m = n×32 is the total number of array elements, λ is the wavelength of the electromagnetic wave used by the phased array, and (y i , z i ) is the position coordinate of the i-th channel on the array plane.

[0104] For a certain subarray, for example, the phase shifter value of the j-th channel in the i-th subarray is:

[0105]

[0106] where, i = 1, 2, … n, n is the total number of subarrays, for example n = 8. j = 1, 2, … 32, 32 is the number of array elements within the subarray. (y ij , z ij ) is the position coordinate of the j-th channel in the i-th subarray on the entire array plane.

[0107] The difference between the phase shifter values of the corresponding channels of the i-th subarray and the 1st subarray is:

[0108]

[0109] In the above formula, when i remains unchanged, for any j, the value of the above formula remains unchanged. That is, for any sub-array, the phase shift values of all its channels can be calculated based on the phase shift value of the channels of the first sub-array.

[0110] Therefore, when the beam control points to (θ 0 , φ 0 ), among the phase shift values of the phase shifters of the phase shifters and attenuators at all levels, the phase shift value of the in-array phase shifter and attenuator:

[0111]

[0112] Where Φ ij is the phase shift value of the j-th channel in the i-th sub-array, i = 1, 2,... n, n is the total number of sub-arrays, j = 1, 2,... 32, and 32 is the number of array elements in the sub-array. (y 1j , z 1j ) is the position coordinate of the j-th array element of the first sub-array. The FPGA of each sub-array assigns phase shift values to the in-array phase shifters and attenuators according to the above formula.

[0113] The phase shift value of the out-of-array phase shifter and attenuator:

[0114]

[0115] Where Δφ′ ij is the phase shift value of the phase shifter and attenuator at the rear end of the i-th sub-array, i = 1, 2,... n, n is the total number of sub-arrays. The FPGA of the entire array assigns phase shift values to the out-of-array phase shifters and attenuators according to the above formula. Thus, the antenna array can achieve accurate target beam pointing.

[0116] The embodiment of the present invention provides a control device for a sub-array extended phased array antenna, and the device includes:

[0117] An acquisition module, configured to acquire the target beam pointing of the phased array antenna; the target beam pointing includes the elevation angle and the azimuth angle;

[0118] A first calibration module, configured to determine the phase shift value of the phase shifter corresponding to each array antenna of each sub-array based on the target beam pointing and pre-calibrated parameters, and control phase shift calibration based on the phase shift value to synchronize the output signal phases of the array antennas within the sub-array;

[0119] A phase difference determination module, configured to determine the phase difference of each sub-array based on the target beam pointing and the relative position difference between the sub-arrays;

[0120] A second calibration module, configured to use the phase difference of the subarray as a phase shift value to control an out-of-array phase shifter to perform out-of-array phase calibration again on the signals with in-array phase synchronization within the subarray, so as to achieve signal phase synchronization of the outputs between the subarrays of the phased array antenna.

[0121] The present invention expands and constructs a phased array antenna through multiple pre-calibrated subarrays. Based on the in-array phase shifters within each subarray, in-array phase calibration is performed to synchronize the phase of each antenna signal within the array. And based on the relative position relationship of each subarray and the target beam direction, the out-of-array phase shifter performs out-of-array phase calibration on the in-array phase synchronized signals, so as to synchronize the phase of the signals output between the subarrays, and achieve phase calibration of the phased array antenna. In the embodiment of the present invention, by performing out-of-array phase calibration outside the pre-calibrated subarray, it is not necessary to adjust each antenna inside the expanded subarray, and it is avoided to calibrate each antenna of each subarray, thereby improving the expansion efficiency of the subarray.

[0122] An embodiment of the present invention provides a control system for a subarray-expanded phased array antenna, including the subarray-expanded phased array antenna as described in any one of the above.

[0123] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A sub-array extended phased array antenna, characterized in that: include: Multiple pre-calibrated sub-arrays; Each sub-array is connected to an out-of-array phase shifter; The subarray includes a plurality of array antennas, each array antenna being connected to an intra-array phase shifter; For any sub-array, each phase shifter in the array is used to perform phase shift calibration on the corresponding array antenna based on pre-calibrated parameters, so as to synchronize the phases of output signals of each array antenna in the array; The out-of-array phase shifter of any subarray is used to determine the phase difference of the subarray according to the relative position difference between the subarray and other subarrays and the target beam pointing, and to re-phase-shift and calibrate the phase-synchronized signal within the subarray according to the phase difference, so as to synchronize the phases of the signals output by the subarrays.

2. The sub-array extended phased array antenna according to claim 1, characterized in that: For any out-of-array phase shifter, it also includes an out-of-array attenuator connected in series with the out-of-array phase shifter; The out-of-array attenuator is used to compensate for the amplitude difference between the sub-arrays.

3. The sub-array extended phased array antenna according to claim 1, characterized in that: It also includes a synthesis network; one side of the synthesis network is connected to the out-of-array phase shifters of each sub-array, and the other side outputs or inputs a radio frequency combined signal.

4. A control method for a sub-array extended phased array antenna, characterized in that: Applicable to the sub-array extended phased array antenna according to any one of claims 1 to 3; the method comprises: Obtaining a target beam pointing of a phased array antenna; the target beam pointing includes an elevation angle and an azimuth angle; Based on the target beam pointing and pre-calibrated parameters, determine the phase shift value of the phase shifter corresponding to each array antenna of each subarray, and control the phase shift calibration based on the phase shift value to synchronize the output signal phases of each array antenna in the subarray; Based on the target beam pointing and the relative position differences between the sub-arrays, the phase difference of each sub-array is determined; The phase difference of the sub-array is used as the phase shift value to control the phase shifter outside the array to perform phase shift calibration again outside the sub-array on the phase-synchronized signal within the sub-array, so as to achieve phase synchronization of the signals output between the sub-arrays of the phased array antenna.

5. The control method of the sub-array extended phased array antenna according to claim 4, characterized in that: The determining of the phase shift value of the phase shifter corresponding to each array antenna of each subarray based on the target beam pointing and the pre-calibrated parameters includes: The phase shift value is determined based on the following formula: Among them, Φ ij represents the phase shift value of the jth array antenna in the i-th subarray, y ij represents the y-axis coordinate of the j-th antenna in the ith subarray, z ij represents the z-axis coordinate of the j-th antenna of the ith subarray, θ0 represents the elevation angle, φ0 represents the azimuth angle, and λ represents the operating wavelength.

6. The control method of the sub-array extended phased array antenna according to claim 4, characterized in that: The determining of the phase difference of each subarray based on the target beam pointing and the relative position difference between the subarrays includes: For any subarray, determine the relative position difference between the subarray and the first subarray; Based on the target beam pointing and the relative position difference between the subarray and the first subarray, the phase difference of the subarray is determined.

7. The control method of the sub-array extended phased array antenna according to claim 6, characterized in that: The step of determining the relative position difference between any sub-array and the first sub-array includes: For the j-th array antenna in any subarray, obtain the relative position difference between the array antenna and the j-th array antenna in the first subarray; Accordingly, determining the phase difference of the subarray based on the target beam pointing and the relative position difference between the subarray and the first subarray includes: Based on the target beam pointing and the relative position difference between the jth array antenna of the subarray and the jth array antenna in the first subarray, the phase difference of the subarray is determined.

8. The control method of the sub-array extended phased array antenna according to claim 6, characterized in that: The determining the phase difference of the subarray based on the target beam pointing and the relative position difference between the jth array antenna of the subarray and the jth array antenna in the first subarray comprises: The phase difference is determined based on the following formula: Among them, Δφ i ′ j represents the phase difference between the jth array antenna of the ith subarray and the jth array antenna of the first subarray; y 1j represents the y-axis coordinate of the jth antenna in the first subarray; z 1j Represents the z-axis coordinate of the jth antenna in the first subarray.

9. A control device for a sub-array extended phased array antenna, characterized in that: The device comprises: An acquisition module, used to acquire the target beam pointing of the phased array antenna; the target beam pointing includes a pitch angle and an azimuth angle; A first calibration module is used to determine the phase shift value of the phase shifter corresponding to each array antenna of each subarray based on the target beam pointing and pre-calibrated parameters, and control the phase shift calibration based on the phase shift value to synchronize the phases of the output signals of each array antenna in the subarray; A phase difference determination module is used to determine the phase difference of each sub-array based on the target beam pointing and the relative position difference between the sub-arrays; The second calibration module is used to use the phase difference of the sub-array as the phase shift value to control the phase shifter outside the array to perform phase shift calibration again on the phase-synchronized signal within the sub-array outside the sub-array, so as to achieve phase synchronization of the signals output between the sub-arrays of the phased array antenna.

10. A control system for a sub-array extended phased array antenna, characterized in that: It comprises the sub-array extended phased array antenna as claimed in any one of claims 1 to 3.

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