A Self-Calibration Method for Circularly Polarized Conformal Phased Array Antennas

Abstract

The present invention discloses a self-calibration method for a circularly polarized conformal phased array antenna. The method includes: amplitude and phase calibration between channels of the circularly polarized conformal linear phased array antenna; polarization phase calibration of the circularly polarized conformal phased array antenna; and self-calibration of the circularly polarized conformal phased array antenna. Through amplitude and phase calibration between channels, the present invention uses a coupler to couple the calibration signal to the calibration distribution network, and realizes one-key calibration of the amplitude and phase between each channel of the circularly polarized conformal phased array by controlling the switch matrix in the calibration distribution network. Based on the antenna polarization phase calibration algorithm, it realizes polarization phase calibration between circularly polarized antenna elements under different beam directions within the full airspace range, and a method that can perform one-key calibration and real-time automatic compensation of the polarization phase difference between elements when the beam direction is different. Compared with the far-field calibration method of calibrating the phased array antenna by erecting a calibration rod, this method can save a large amount of manpower, material resources and time.

Description

Technical Field

[0001] The present invention relates to the technical field of antennas, and particularly to a self-calibration method for a circularly polarized conformal phased array antenna. Background Art

[0002] In modern measurement and control, radar, and communication systems, phased array antennas have received extensive attention from scholars due to their advantages such as fast scanning, multi-beam formation, and beam shape agility. A conformal phased array antenna refers to an antenna whose shape is no longer a traditional planar array, but a curved surface or spherical phased array that conforms to the carrier platform to cover a larger airspace. The accuracy of the amplitude and phase excitation of each channel of the phased array antenna will directly affect the performance of the phased array antenna, such as pointing accuracy, gain, and axial ratio. Therefore, amplitude and phase calibration of the phased array antenna is extremely important. For a circularly polarized conformal phased array antenna, since the installation postures of the antenna elements are different, the polarization vectors of each element are different, resulting in a large antenna polarization phase difference, and the polarization phase differences of the antenna are different under different beam pointings, thus affecting the antenna performance. Currently, existing calibration methods all have certain limitations for the calibration of circularly polarized conformal phased array antennas.

[0003] Currently, the mainstream phased array calibration methods are as follows: 1) In-field calibration method: It can only calibrate the amplitude and phase errors between the channels of the phased array and cannot calibrate the polarization phase difference of the antenna; 2) Coupling calibration method: It is only effective for a transceiver common aperture array surface and cannot calibrate the polarization phase difference of the antenna; 3) Near-field calibration method: For large-scale phased array antennas, it is impossible to use a sampling frame for near-field sampling. Even if a drone is used to replace the sampling frame, there will still be an impact on the hovering accuracy, and the workload is huge; 4) Far-field calibration method: All far-field calibration methods require the erection of a far-field calibration pole, which requires a huge amount of manpower, material resources, and time workload, and can only be calibrated in one direction at a time. For antennas in a large airspace (even the entire airspace), multiple calibration poles need to be erected in different directions. Among the existing calibration methods, the in-field calibration method and the coupling calibration method cannot calibrate the polarization phase of the antenna, while the near-field calibration method and the far-field calibration method can achieve the calibration of the polarization phase of the antenna and the phase between channels. However, for large-scale conformal phased arrays, the workload is huge, and it is difficult to achieve calibration in multiple airspaces (even the entire airspace). How to quickly and efficiently calibrate large-scale circularly polarized conformal phased array antennas is an urgent problem to be solved. Summary of the Invention

[0004] Aiming at the calibration of circularly polarized conformal phased array antennas, the traditional far-field calibration method requires the erection of a far-field calibration pole, with a huge workload and difficulties in calibrating multiple airspaces or even the entire airspace. The present invention provides a self-calibration method for circularly polarized conformal phased array antennas, which is simple to implement, has strong versatility, can calibrate the phase difference between channels with one key, and can perform real-time automatic calibration of the antenna polarization phase difference under different beam pointings.

[0005] To achieve the above object, a self - calibration method for a circularly polarized conformal phased array antenna adopted by the present invention includes the following steps:

[0006] Step 1: Amplitude and phase calibration between channels of the circularly polarized conformal phased array antenna.

[0007] The digital board generates a downlink calibration signal, which is transmitted to the RF front - end through the downlink calibration distribution network. The signal is coupled to the downlink receiving link through the coupler of the RF front - end, and then the signal is transmitted to the digital board by the receiving link. By comparing the received downlink signal with the initially generated calibration signal, the amplitude and phase calibration of the receiving channel are achieved;

[0008] The digital board generates an uplink calibration signal, which is transmitted to the RF front - end through each uplink transmitting link. The signal is coupled to the uplink calibration distribution network through the coupler of the RF front - end, and then the signal is transmitted to the digital board by the uplink calibration distribution network. By comparing the received uplink signal with the initially generated calibration signal, the amplitude and phase calibration of the transmitting channel are achieved.

[0009] Step 2: Polarization phase calibration of the circularly polarized conformal phased array antenna.

[0010] Define the vector of the beam pointing in the global coordinate system as Taking the direction as the z - axis direction, establish a local coordinate system (x1, y1, z1) according to the right - hand coordinate system principle. Project the (or all use components) electric - field components of each element in the phased array in its own local coordinate system onto the plane x1oy1 perpendicular to the beam pointing , and construct a reference vector orthogonal to the beam - pointing vector The projection vector of each element on the plane x1oy1 and the vector included angle of the reference vector

[0011] are the antenna polarization phase calibration values of each element.

[0012] The software deployed in the upper computer can complete the amplitude and phase calibration process between channels in Step 1 with one key. When the beam pointing changes, the software deployed in the upper computer can also achieve the automatic calibration of the antenna polarization phase under different beam pointings in Step 2. The amplitude calibration of the circularly polarized conformal phased array antenna can be achieved through the amplitude calibration between channels; by combining the inter - channel phase calibration value and the antenna polarization phase calibration value, the final phase weight can be obtained to achieve phase calibration.

[0013]

[0014] where φ i is the phase weight of the i-th array element, and φ i ' is the inter-channel phase calibration value of the i-th array element, and β i is the antenna polarization phase calibration value of the i-th array element.

[0015] Furthermore, the inter-channel phase self-calibration in Step 1 specifically refers to: the downlink calibration signal generated in the digital board is output by the DA to the downlink calibration distribution network. The downlink calibration distribution network has an upconverter and a switch matrix. The signal is upconverted from the intermediate frequency to the radio frequency signal by the upconverter, and then sequentially transmitted to the couplers of each downlink through the switch matrix in a certain order, coupled into each receiving link. The signal is downconverted to the intermediate frequency through the receiving channel and then transmitted to the digital board. By comparing the received downlink signal with the initially generated calibration signal, the amplitude and phase differences of each receiving channel can be obtained, and the weights of each channel are changed according to the amplitude and phase differences between channels obtained by calibration; the uplink calibration signal generated in the digital board is output by the DA. The signal is upconverted to the radio frequency signal through the uplink and coupled into the uplink calibration distribution network through the coupler. The uplink calibration distribution network has a downconverter and a switch matrix. The signal is sequentially transmitted to the downconverter through the switch matrix in a certain order. The downconverter then converts the radio frequency signal to the intermediate frequency signal and transmits it to the digital board. The digital board compares the sampled digital signal with the initially generated calibration signal to obtain the amplitude and phase differences of each transmitting channel, and changes the weights of each channel according to the amplitude and phase differences between channels obtained by calibration.

[0016] Furthermore, the calibration processes of the uplink and downlink channels in Step 1 can both be controlled by the program of the upper computer to achieve one-key automatic calibration of all channels.

[0017] Furthermore, the antenna polarization phase calibration in Step 2 specifically refers to: each array element in the conformal phased array can be regarded as obtained by rotating and translating a certain unit in the global coordinate system. Each array element can decompose the electric field vector along the x and y directions of its own local coordinate system. Different postures of each array element will result in different directions of the decomposed electric field vectors, thus generating polarization phase differences. Define the vector of the beam pointing direction in the global coordinate system as Taking the direction as the z-axis direction, a local coordinate system (x1, y1, z1) is established according to the right-hand coordinate system principle. The electric field components of each array element in the phased array are projected onto the plane x1oy1 perpendicular to the beam pointing direction, and a reference vector orthogonal to the beam pointing vector is constructed. Calculate the projection vector of each array element on the plane x1oy1 and the reference vector The vector included angle is the antenna phase calibration value of each element of the conformal phased array antenna under the current beam pointing. When the beam pointing changes, the antenna polarization phase difference of each element of the conformal phased array can be automatically calibrated in real time based on the above method.

[0018]

[0019]

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] Strong universality, can be widely applied to circularly polarized conformal phased arrays of different scales. For the calibration of circularly polarized conformal phased array antennas, the present invention uses a calibration distribution network to achieve amplitude and phase calibration between channels, and then combines an antenna polarization phase calibration algorithm to achieve self-calibration of the conformal phased array antenna. This method is simple to implement, can be applied to conformal phased arrays in various forms such as curved surfaces and spherical surfaces, and can adapt to different scales.

[0022] Convenient operation, saving labor, material and time costs. For the calibration of circularly polarized conformal phased array antennas, all calibration processes can be controlled by the software deployed in the upper computer to achieve one-key automatic calibration. Compared with the traditional far-field calibration method that requires setting up calibration poles, calibration antennas, and a large number of calibration devices, the present invention can save a large amount of labor, material and time costs. Especially for large-scale conformal phased array antennas, the workload of field calibration is huge, and there is a problem of re-calibration when the field environment changes.

[0023] Can achieve large airspace or even full airspace calibration. For the calibration of circularly polarized conformal phased array antennas, due to the different installation postures of the antenna elements, the polarization vectors of each element are different, resulting in a large antenna polarization phase difference, and the polarization phase differences of the antenna under different beam pointings are different. The traditional far-field calibration method can only perform calibration under one beam pointing each time, and it is difficult to achieve large airspace or even full airspace calibration. However, the antenna polarization phase calibration algorithm adopted by the present invention can calibrate the phase weights of each element in real time according to different beam pointings to achieve full airspace calibration.

[0024] Suitable for circularly polarized conformal phased array antennas of different scales and forms, and can be applied to fields such as measurement and control, communication, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic block diagram of the uplink and downlink components in a circularly polarized conformal phased array antenna;

[0026] Figure 2 is a schematic diagram of the electric field vectors of each element in a circularly polarized conformal phased array antenna;

[0027] Figure 3 It is the simulated radiation pattern of the circularly polarized conformal phased array antenna before and after calibration when the beam pointing elevation angle is 90° (i.e., pointing to the top of the sphere);

[0028] Figure 4 It is the simulated radiation pattern of the circularly polarized conformal phased array antenna before and after calibration when the beam pointing elevation angle is 60°;

[0029] Figure 5 It is the simulated radiation pattern of the circularly polarized conformal phased array antenna before and after calibration when the beam pointing elevation angle is 30°.

[0030] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Detailed Embodiments

[0031] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0033] Refer to Figures 1-5 . According to the present invention, the following steps are taken:

[0034] Step 1: Amplitude and phase calibration between channels of the circularly polarized conformal phased array antenna.

[0035] The digital board generates a downlink calibration signal, which is transmitted to the RF front end through the downlink calibration distribution network. The signal is coupled to the downlink receiving link through the coupler of the RF front end, and then transmitted to the digital board by the receiving link. By comparing the received downlink signal with the initially generated calibration signal, the amplitude and phase calibration of the receiving channel are realized;

[0036] The digital board generates an uplink calibration signal, which is transmitted to the RF front end through each uplink transmission link. The signal is coupled to the uplink calibration distribution network through the coupler of the RF front end, and then transmitted to the digital board by the uplink calibration distribution network. By comparing the received uplink signal with the initially generated calibration signal, the amplitude and phase calibration of the transmitting channel are realized.

[0037] Step 2: Polarization phase calibration of the circularly polarized conformal phased array antenna.

[0038] Define the vector of the beam pointing in the global coordinate system as Taking The direction as the z-axis direction, establish a local coordinate system (x1, y1, z1) according to the right-hand coordinate system principle. The (or all use The electric field component projects along the coordinate system (x1, y1, z1) onto the plane x1oy1 perpendicular to the beam direction and constructs a reference vector orthogonal to the beam direction vector The projection vectors of each array element on the plane x1oy1 and the reference vector The vector angle is the antenna polarization phase calibration value of each array element.

[0039] Step 3: Self-calibration of the circularly polarized conformal phased array antenna.

[0040] The software deployed in the host computer can complete the amplitude and phase calibration process between channels in Step 1 with one key. When the beam direction changes, the software deployed in the host computer can also achieve the automatic calibration of the antenna polarization phase under different beam directions in Step 2. The amplitude calibration of the circularly polarized conformal phased array antenna can be achieved through the amplitude calibration between channels; combining the inter-channel phase calibration value and the antenna polarization phase calibration value can obtain the final phase weight, as shown in Equation (1), to achieve phase calibration.

[0041]

[0042] In the formula, φ i is the phase weight of the i-th array element, φ i ' is the inter-channel phase calibration value of the i-th array element, and β i is the antenna polarization phase calibration value of the i-th array element

[0043] To illustrate the self-calibration method of the circularly polarized conformal phased array antenna, taking the circularly polarized spherical conformal phased array antenna as an example, the specific processing steps are as follows:

[0044] Refer to Figure 1, for the conformal phased array uplink and downlink, from the antenna to the back-end AD / DA, it successively includes antenna elements, 3dB hybrids, filters, couplers, T / R modules, and a digital board (AD / DA is on the digital board). The calibration distribution network is a network composed of a switch matrix. One end of the network is connected to the couplers of each channel, and the other end is connected to the digital board. The amplitude and phase characteristics of each channel inside the network are consistent. By controlling the gating of the switches in the calibration distribution network, the downlink calibration signal can be sequentially transmitted from the digital to the couplers of each receiving channel, and the uplink calibration signal can be sequentially transmitted from the coupler to the digital board. Receiving channel calibration: The downlink calibration signal generated in the digital board is output by the DA to the downlink calibration distribution network, and then the signal is coupled to each receiving link through the coupler. Finally, the signal is down-converted to the intermediate frequency by the R module and then transmitted to the digital board; Transmitting channel calibration: The uplink calibration signal generated in the digital board is output by the DA. The signal is up-converted to the radio frequency signal by the T module, coupled to the uplink calibration distribution network through the coupler, and finally transmitted to the digital board by the uplink calibration network.

[0045] The downlink calibration distribution network includes a switch matrix and an upconverter. After the downlink calibration signal generated by the digital board enters the downlink calibration distribution network, the signal is first converted from the intermediate frequency to the radio frequency by the upconverter, and then enters the switch matrix. The other end of the switch matrix is respectively connected to the couplers of all downlink channels. By controlling the switching of the switches in the switch matrix, the signal will sequentially enter each receiving channel and then be transmitted back to the digital board along the downlink. By reasonably designing to ensure that the amplitude and phase characteristics from the switch matrix to each receiving channel are consistent. Therefore, by comparing the signal transmitted back to the digital board from each receiving channel with the initial calibration signal, the amplitude and phase characteristics of each receiving channel itself can be obtained, and thus the weights of each channel can be changed to achieve the calibration of the receiving channels.

[0046] The uplink calibration distribution network includes a switch matrix and a downconverter. The uplink calibration signal generated by the digital board is coupled to the switch matrix in the calibration distribution network through the coupler. The other end of the switch matrix is connected to the downconverter. By controlling the switching of the switches in the switch matrix, the uplink calibration signals of each channel sequentially pass through the downconverter and then are transmitted back to the digital board. Similar to the downlink calibration distribution network, the amplitude and phase characteristics from the switch matrix to each transmitting channel in the uplink calibration distribution network are consistent. Therefore, by comparing the signal transmitted back to the digital board from each transmitting channel with the initial calibration signal, the amplitude and phase characteristics of each transmitting channel itself can be obtained, and thus the weights of each channel can be changed to achieve the calibration of the transmitting channels.

[0047] After the hardware equipment for amplitude and phase calibration between channels of the circularly polarized phased array antenna is available, its operation process can be controlled by the software deployed in the upper computer to achieve one-key calibration of the amplitude and phase characteristics of all channels.

[0048] Refer to Figure 2 , the half-wavelength of the circularly polarized antenna element spacing is asFigure 2 arranged in a spherical conformal phased array in the manner shown Figure 2 In [it], the circular auxiliary lines are similar to the latitude lines, dividing the hemisphere into multiple latitudes from top to bottom, and different numbers of antenna array elements are evenly arranged on each latitude. Figure 2 In [it], the center of each group of orthogonal vectors represents the center of an antenna array element. Taking the center of this element as the origin of the local coordinate system of the element, the maximum radiation direction of this element is along the spherical radius direction, serving as the z-axis of the local coordinate system of the element, and the local coordinate systems of each element are established respectively according to the right-hand rule. Figure 2 In [it], the solid line and the dashed line in each group of orthogonal vectors respectively represent the electric field vectors obtained by decomposing the corresponding element along the x and y axis directions in its own local coordinate system. From Figure 2 it can be seen that each element of the spherical conformal phased array can be regarded as obtained by rotating and translating a certain element on the sphere in the global coordinate system, and during the rotation process, the direction of the electric field vector of each element will change. For a circularly polarized antenna, the change in the direction of the electric field vector will cause the phase received by each element for the same target to change, which is the antenna polarization phase difference.

[0049] Figure 2 The x electric field component of the i-th element in [it] is (or all calculated using the y component). Without loss of generality, it is assumed that the beam direction is defined in the spherical coordinate system as Then the beam direction vector As shown in Equation (2). Along the direction as the z-axis direction, a relative coordinate system (x1, y1, z1) is established according to the right-hand rule, and the constructed reference vector (as shown in Equation (3)) is orthogonal to , then is parallel to the plane x1oy1. Project the electric field component of the i-th element onto the plane x1oy1 to obtain its projection vector Then the vector and the reference vector The vector angle of is the antenna polarization phase calibration value of the i-th element, as shown in Equation (4).

[0050]

[0051]

[0052]

[0053] Refer to Figures 2-5 , which respectively give the spherical Figure 2The calculation results of the conformal phased array when the beam is pointed at an elevation angle of 90° (i.e., pointing to the top of the sphere), 60°, and 30° are compared with those when the antenna polarization phase is calibrated and not calibrated. When the beam is pointed at a low elevation angle, the direction of the electric field vector of the array element itself at the low elevation angle of the sphere changes little (see Figure 2 ), the antenna polarization phase calibration has little effect on performance (see Figure 5 ); When the beam is pointed at a high elevation angle, especially at the top of the sphere, the direction of the electric field vector of the array element at the high elevation angle of the spherical surface changes greatly (see Figure 2 ), if the antenna is not calibrated, the performance of the phased array pattern will be seriously degraded (see Figures 3-4 ), the circularly polarized conformal phased array antenna self-calibration method proposed in the present invention can calibrate the phase difference caused by the antenna polarization, so that the radiation pattern is significantly improved. In addition, by deploying the algorithm in the host computer, the method can realize real-time automatic calibration of the antenna polarization phase with different beam pointing directions, without the need to set up calibration poles in multiple directions for manual calibration.

[0054] A circularly polarized conformal phased array antenna self-calibration method is adopted to realize one-click calibration of amplitude and phase between channels of the phased array through a calibration distribution network. Combined with the antenna polarization phase calibration algorithm, real-time automatic calibration of the amplitude and phase of the phased array under different beam pointing directions in the entire airspace can be achieved. Compared with the traditional far-field calibration method, it effectively reduces the manpower, material and time costs, and realizes the full airspace calibration of large-scale conformal phased arrays.

[0055] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0056] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0057] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-described example methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. This computer software product is stored in a storage medium as described above (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions for causing a terminal device (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in various embodiments of the present invention.

[0058] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. A self - calibration method for a circularly polarized conformal phased array antenna, characterized in that The method includes the following steps: S1: Amplitude and phase calibration between channels of the circularly polarized conformal linear array antenna; specifically, step S1 includes: S101: The digital board generates a downlink calibration signal, which is transmitted to the RF front-end through the downlink calibration distribution network. The signal is coupled to the downlink receiving link through the coupler of the RF front-end, and then transmitted to the digital board by the receiving link. By comparing the received downlink signal with the initially generated calibration signal, the amplitude and phase calibration of the receiving channel are achieved; S102: The digital board generates an uplink calibration signal, which is transmitted to the RF front-end through each uplink transmission link. The signal is coupled to the uplink calibration distribution network through the coupler of the RF front-end, and then transmitted to the digital board by the uplink calibration distribution network. By comparing the received uplink signal with the initially generated calibration signal, the amplitude and phase calibration of the transmission channel are achieved. S2: Polarization Phase Calibration of Circularly Polarized Conformal Phased Array Antenna; The specific steps of step S2 include: S201: Define the vector of the beam pointing in the global coordinate system as , and establish a local coordinate system with the direction as the z-axis direction according to the right-hand coordinate system principle ; S202: Project the or component electric field components of each element in the phased array in its own local coordinate system along the coordinate system onto the plane perpendicular to the beam pointing ; S203: Construct a reference vector orthogonal to the beam pointing vector . The vector angle between the projection vector of each element on the plane and the reference vector is the antenna polarization phase calibration value of each element; S3: Self-calibration of the circularly polarized conformal phased array antenna.

2. The self-calibration method of the circularly polarized conformal phased array antenna according to claim 1, characterized in that, In step S1: The digital board generates a downlink calibration signal, which is sequentially transmitted to the couplers of each downlink channel through the switch matrix in the downlink calibration distribution network. The signal coupled to each channel is then transmitted to the digital board through the R components of the downlink link. By comparing the received downlink signal with the initially generated calibration signal, the amplitude and phase characteristics of each receiving channel are obtained, and the calibration of the downlink receiving channel is achieved by changing the weights of each channel. The digital board generates an uplink calibration signal, which is transmitted to the coupler through the T components of the uplink link. The signal is coupled to the uplink calibration distribution network and then sequentially transmitted to the digital board by controlling the switch matrix. By comparing the received uplink signal with the initially generated calibration signal, the amplitude and phase characteristics of each transmission channel are obtained, and the calibration of the transmission channel is achieved by changing the weights of each channel.

3. The self-calibration method of the circularly polarized conformal phased array antenna according to claim 1, characterized in that, In the said step S3, it specifically includes: Define the beam pointing vector in the global coordinate system as , and establish a local coordinate system with the direction of as the z-axis direction according to the right-hand coordinate system principle , construct a reference vector orthogonal to , then is parallel to the plane ; ​ Each element in the conformal phased array can be regarded as obtained by rotating and translating a certain unit in the global coordinate system. Each element can perform electric field vector decomposition along the x and y axes in its own local coordinate system. Among them, the component or component is , the projection vector of the vector on the plane is . Then, the projection vector of the i-th element on the plane and the reference vector The vector angle is the polarization phase calibration value of the element, and the polarization phase of the circularly polarized conformal phased array in different directions is automatically calibrated in real time.

4. The self-calibration method of the circularly polarized conformal phased array antenna according to claim 3, wherein In the step S3, the polarization phase calibration value has the following expression, specifically: 。 5. The self-calibration method of the circularly polarized conformal phased array antenna according to claim 4, wherein The said step S3 specifically includes: Combining the inter-channel phase calibration value and the antenna polarization phase calibration value to obtain the final phase weight to achieve phase calibration; among them, the final phase weight is specifically: wherein, is the phase weight of the i-th array element, is the inter-channel phase calibration value of the i-th array element, is the antenna polarization phase calibration value of the i-th array element.

6. The self-calibration method of the circularly polarized conformal phased array antenna according to claim 1, characterized in that The amplitude and phase calibration between channels of the circularly polarized conformal linear array antenna in step S1 and the polarization phase calibration of the circularly polarized conformal phased array antenna in step S2 are automatically realized by the software deployed in the upper computer.

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