Rapid positioning method and device for compact range feed source phase center

Abstract

The invention discloses a rapid positioning method and device for a compact range feed source phase center, and belongs to the field of electromagnetic measurement. The method comprises the following steps: establishing a three-dimensional coordinate system taking the vertex of a parabolic reflector as an original point and the focal line of the parabolic reflector as an X axis according to a position relationship between the parabolic reflector and a feed source phase center; according to the spatial position relationship among the feed source phase center, the parabolic reflector and the section in the dead zone in the three-dimensional coordinate system, establishing an incident offset focus equation of the feed source phase center; inputting the coordinates of a plurality of preset to-be-observed points on the cross section in the quiet zone into the incident offset focus equation, and calculating and outputting to obtain a coordinate estimation value of a feed source phase center; and calibrating and positioning the feed source phase center according to the coordinate estimation value so as to enable the coordinate of the feed source phase center to coincide with the focus of the parabolic reflector. The feed source phase center can be quickly positioned, and the quiet zone phase performance is improved.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic measurement technology, and in particular to a method and apparatus for rapidly locating the phase center of a compact field feed source. Background Technology

[0002] Since its emergence in the 1960s and 70s, compact field measurement technology has gradually replaced traditional far-field measurement methods, becoming the primary means of measuring the electromagnetic properties of various scatterers and radiators, due to its advantages such as being unaffected by weather and interference clutter, requiring limited testing sites, and exhibiting good measurement consistency. Compact field technology converts the spherical waves emitted by the feed source into plane waves at close range through a reflecting surface, thereby simulating the conditions of far-field testing. Its phase performance within the quiet zone directly affects the final test results.

[0003] In related technologies, feed defocus refers to a phenomenon in which the phase center of the feed deviates from the focal point of the compact field reflecting surface. It is one of the important reasons for the deterioration of the phase performance in the quiet zone. In the actual application of the compact field, due to the inherent processing errors and assembly errors of the feed and feed turntable, the deterioration of the phase performance in the quiet zone caused by feed defocus is ubiquitous.

[0004] Therefore, there is an urgent need for a method and apparatus for rapid positioning of the phase center of a compressed field feed to solve the above-mentioned technical problems. Summary of the Invention

[0005] This invention provides a method and apparatus for rapidly locating the phase center of a compact field feed, which can quickly locate the feed phase center and improve the phase performance in the quiet zone. The technical solution is as follows: On the one hand, a method for fast positioning of the phase center of a compact field feed is provided, the method comprising: Based on the positional relationship between the parabolic reflector and the feed phase center, a three-dimensional coordinate system is established with the vertex of the parabolic reflector as the origin and the focal line of the parabolic reflector as the X-axis. Based on the spatial relationship between the feed phase center, the parabolic reflector, and the cross section in the quiet zone in the three-dimensional coordinate system, the incident defocusing equation of the feed phase center is established. Input the coordinates of multiple preset observation points on the cross section in the quiet zone into the incident defocusing equation, and calculate and output the estimated coordinate value of the feed phase center. The feed phase center is calibrated and positioned based on the estimated coordinates so that the coordinates of the feed phase center coincide with the focal point of the parabolic reflector.

[0006] On the other hand, a rapid positioning device for the phase center of a compressed field feed source is provided, the device comprising: The first modeling unit is used to establish a three-dimensional coordinate system with the vertex of the parabolic reflector as the origin and the focal line of the parabolic reflector as the X-axis, based on the positional relationship between the parabolic reflector and the feed phase center. The second modeling unit is used to establish the incident defocusing equation of the feed phase center based on the spatial positional relationship between the feed phase center, the parabolic reflector and the cross section in the quiet zone in the three-dimensional coordinate system. The calculation unit is used to input the coordinates of multiple preset observation points on the cross section in the quiet zone into the incident defocusing equation, and calculate and output the estimated coordinate value of the feed phase center. The positioning unit is used to calibrate and position the feed phase center according to the coordinate estimation value, so that the coordinates of the feed phase center coincide with the focal point of the parabolic reflector.

[0007] On the other hand, a computer device is provided, the computer device including a memory and a processor, the memory for storing a computer program, and the processor for executing the computer program stored in the memory to implement the steps of the above-described method for rapidly locating the phase center of a compact field feed source.

[0008] On the other hand, a computer-readable storage medium is provided, wherein a computer program is stored therein, and when the computer program is executed by a processor, the steps of the above-described method for rapidly locating the phase center of a compacted field feed source are implemented.

[0009] On the other hand, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps of the fast positioning method for the phase center of the compressed field feed described above.

[0010] The technical solution provided by this invention can bring at least the following beneficial effects: First, by establishing a three-dimensional coordinate system, the analytical equation of the parabolic reflector and the coordinates of each point are determined; then, based on the reflection relationship of rays in space, the spatial positional relationship of each coordinate point is established, and the relationship is simplified to obtain the defocusing formula; finally, the measured phase data of multiple sets of cross-sections in the quiet zone are substituted into the defocusing formula to obtain the estimated coordinate value of the feed phase center. This method obtains the defocusing formula of a single parabolic surface of revolution based on the spatial positional relationship of each relevant coordinate point. By substituting multiple sets of measured data from the quiet zone, the accurate coordinates of the feed phase center can be obtained, and it can be adjusted to coincide with the focal point of the reflector, eliminating the deterioration of the quiet zone phase performance caused by feed defocusing and achieving the effect of improving the quiet zone phase quality. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a flowchart of a method for rapid positioning of the phase center of a compact field feed source according to an embodiment of the present invention; Figure 2 This is a schematic diagram of a parabolic reflector defocusing calculation scenario provided in an embodiment of the present invention; Figure 3 This is a structural diagram of a rapid positioning device for the phase center of a compressed field feed provided in an embodiment of the present invention; Figure 4 This is a hardware architecture diagram of a computer device provided in an embodiment of the present invention. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0014] As mentioned earlier, due to inherent processing and assembly errors in the feed and feed turntable, the deterioration of the static phase performance caused by feed misfocus is ubiquitous.

[0015] Based on this, the concept of the present invention is to derive the defocusing formula for the parabolic reflector and calculate the accurate position of the feed phase center based on multiple sets of phase data measured in the quiet zone.

[0016] The specific implementation of the above concept is described below.

[0017] Please refer to Figure 1 The present invention provides a method for rapid positioning of the phase center of a compact field feed, the method comprising: Step 100: Based on the positional relationship between the parabolic reflector and the feed phase center, establish a three-dimensional coordinate system with the vertex of the parabolic reflector as the origin and the focal line of the parabolic reflector as the X-axis. Step 102: Based on the spatial relationship between the feed phase center, the parabolic reflector, and the cross section in the quiet zone in the three-dimensional coordinate system, establish the incident defocusing equation of the feed phase center; Step 104: Input the coordinates of multiple preset observation points on the cross section in the quiet zone into the incident defocusing equation, and calculate and output the estimated coordinate value of the feed phase center. Step 106: The feed phase center is calibrated and positioned according to the estimated coordinates so that the coordinates of the feed phase center coincide with the focal point of the parabolic reflector.

[0018] In this embodiment of the invention, a three-dimensional coordinate system is first established to determine the analytical equation of the parabolic reflector and the coordinates of each point. Then, based on the reflection relationship of rays in space, the spatial positional relationship of each coordinate point is established, and the relationship is simplified to obtain the defocusing formula. Finally, the measured phase data of multiple sets of sections in the quiet zone are substituted into the defocusing formula to obtain the estimated coordinates of the feed phase center. This method derives the defocusing formula for a single parabolic surface of revolution based on the spatial positional relationship of each relevant coordinate point. Substituting multiple sets of measured data from the quiet zone yields the accurate coordinates of the feed phase center, which is then adjusted to coincide with the focal point of the reflector, eliminating the deterioration of the quiet zone phase performance caused by feed defocusing and achieving the effect of improving the quiet zone phase quality.

[0019] The following description Figure 1 The execution method for each step is shown.

[0020] First, for step 100, based on the positional relationship between the parabolic reflector and the feed phase center, a three-dimensional coordinate system is established with the vertex of the parabolic reflector as the origin and the focal line of the parabolic reflector as the X-axis.

[0021] Based on the spatial relationship between the reflector and the feed source, a three-dimensional coordinate system is established with the vertex of the parabolic reflector as the origin and the focal line of the parabolic reflector as the X-axis. The coordinates of each point are obtained. The defocusing calculation scenario of the reflector is as follows: Figure 2 As shown, the phase center point of the feed source after focusing is ( x 0, y 0, z 0), The coordinates of the reflection point on the reflecting surface are ( x r , y r , z r The coordinates of the point to be observed within the cross section of the quiet zone are ( x , y , z ); Then, for step 102, based on the spatial relationship between the feed phase center, the parabolic reflector, and the cross section in the quiet zone in the three-dimensional coordinate system, the incident defocusing equation of the feed phase center is established.

[0022] In this embodiment of the invention, the incident defocusing equation is established in the following manner: Based on the relationship between the coordinates of the observation point on the cross section in the quiet zone and the focal length of the parabolic reflector, the analytical equation of the parabolic reflector is established: in,( x , y , z ) represents the coordinates of the point to be observed within the cross section of the quiet zone; F represents the focal length.

[0023] Next, based on the set relationship of the incident ray, the reflected ray, and the normal, the geometric constraints of the feed phase center point, the reflection point, and the observation point in the three-dimensional coordinate system are determined; Finally, based on the phase measurement data corresponding to the observation point, the combined analytical equation and geometric constraints are derived and simplified to obtain the incident defocusing equation: in,( x 0, y 0, z 0) represents the coordinates of the feed phase center point after focusing; x r , y r , z r ) represents the coordinates of the reflection point on the reflecting surface; Δ φ The absolute phase difference; λ The wavelength corresponding to the operating frequency; x m This represents the x-axis coordinate of the test location in the quiet zone.

[0024] For step 104, the coordinates of multiple preset observation points on the cross section in the quiet zone are input into the incident defocusing equation, and the estimated coordinate value of the feed phase center is calculated and output.

[0025] In this embodiment of the invention, to ensure the accuracy of the calculation, five points—the center point of the cross-section in the quiet zone, the two endpoints of the horizontal section, and the two endpoints of the vertical section—are selected for the calculation. Table 1 below shows the results of 10 repeated calculations for a specific example of a defocused reflector. The focal length of the reflector is 8.483m, and the feed source is defocused 0.01m in the positive y-axis direction. The overall deviation does not exceed 1mm, demonstrating extremely high calculation accuracy.

[0026] Table 1 For step 106, the feed phase center is calibrated and positioned according to the coordinate estimation value so that the coordinates of the feed phase center coincide with the focal point of the parabolic reflector.

[0027] In this embodiment of the invention, the coordinate estimate of the current feed phase center is obtained according to the above steps, and is adjusted to coincide with the focal point of the reflector by a high-precision positioning device, thereby eliminating the deterioration of the quiet zone phase performance caused by the feed defocus and achieving the effect of improving the quiet zone phase quality.

[0028] Please refer to Figure 3This invention provides a device for rapidly locating the phase center of a compact field feed, the device comprising: The first modeling unit 300 is used to establish a three-dimensional coordinate system with the vertex of the parabolic reflector as the origin and the focal line of the parabolic reflector as the X-axis, based on the positional relationship between the parabolic reflector and the feed phase center. The second modeling unit 302 is used to establish the incident defocusing equation of the feed phase center based on the spatial positional relationship between the feed phase center, the parabolic reflector and the cross section in the quiet zone in the three-dimensional coordinate system. The calculation unit 304 is used to input the coordinates of multiple preset observation points on the cross section in the quiet zone into the incident defocusing equation, and calculate and output the estimated coordinate value of the feed phase center. The positioning unit 306 is used to calibrate and position the feed phase center according to the coordinate estimation value so that the coordinates of the feed phase center coincide with the focal point of the parabolic reflector.

[0029] In this embodiment of the invention, establishing the incident defocusing equation of the feed phase center based on the spatial positional relationship between the feed phase center, the parabolic reflector, and the cross-section in the quiet zone in a three-dimensional coordinate system includes: Based on the relationship between the coordinates of the observation point on the cross section in the quiet zone and the focal length of the parabolic reflector, the analytical equation of the parabolic reflector is established. Based on the set relationship of the incident ray, reflected ray, and normal, determine the geometric constraints of the feed phase center point, reflection point, and observation point in the three-dimensional coordinate system; Based on the phase measurement data corresponding to the observation point, the combined analytical equation and geometric constraints are derived and simplified to obtain the incident defocusing equation.

[0030] In this embodiment of the invention, the analytical equation is established using the following formula: in,( x , y , z ) represents the coordinates of the point to be observed within the cross section of the quiet zone; F represents the focal length.

[0031] In this embodiment of the invention, the incident defocusing equation is established by the following formula: in,( x 0, y 0, z 0) represents the coordinates of the feed phase center point after focusing; xr , y r , z r ) represents the coordinates of the reflection point on the reflecting surface; Δ φ The absolute phase difference; λ The wavelength corresponding to the operating frequency; x m This represents the x-axis coordinate of the test location in the quiet zone.

[0032] In this embodiment of the invention, the step of inputting the coordinates of multiple preset observation points on the cross section in the quiet zone into the incident defocusing equation and calculating the output to obtain the coordinate estimate of the feed phase center includes: Acquire the phase measurement data and coordinate values ​​corresponding to each preset observation point; The phase measurement data and coordinate values ​​are substituted into the incident defocusing equation for numerical calculation, and the estimated coordinates of the feed phase center are output.

[0033] In this embodiment of the invention, the preset observation point includes the center point on the cross section in the quiet zone, the two endpoints of the horizontal section, and the two endpoints of the vertical section.

[0034] It should be noted that the rapid positioning device for the phase center of the compacted field feed provided in the above embodiments is only an example of the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the rapid positioning device for the phase center of the compacted field feed provided in the above embodiments and the rapid positioning method for the phase center of the compacted field feed belong to the same concept. The specific implementation process is detailed in the method embodiments and will not be repeated here.

[0035] Embodiments of this application also provide a computer device, please refer to... Figure 4 The computer device includes a processor and a memory, the memory storing at least one instruction, at least one program, code set or instruction set, the at least one instruction, at least one program, code set or instruction set being loaded and executed by the processor to implement the fast positioning method for the compact field feed phase center provided in the above method embodiments.

[0036] Embodiments of this application also provide a computer-readable storage medium storing at least one instruction, at least one program, code set, or instruction set, wherein the at least one instruction, at least one program, code set, or instruction set is loaded and executed by a processor to implement the fast positioning method for the compact field feed phase center provided in the above-described method embodiments.

[0037] Embodiments of this application also provide a computer program product, which includes a computer program. A processor of a computer device reads the computer program from a computer-readable storage medium and executes the computer program, causing the computer device to perform the fast positioning method for the compact field feed phase center described in any of the above embodiments.

[0038] For ease of description, the above systems or devices are described separately as various modules or units based on their functions. Of course, in implementing this application, the functions of each unit can be implemented in one or more software and / or hardware components.

[0039] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application, 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 can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0040] Finally, it should be noted that in this document, relational terms such as first, second, third, and fourth are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0041] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A method for fast positioning of the phase center of a compact range feed, characterized in that, The method includes: Based on the positional relationship between the parabolic reflector and the feed phase center, a three-dimensional coordinate system is established with the vertex of the parabolic reflector as the origin and the focal line of the parabolic reflector as the X-axis. Based on the spatial relationship between the feed phase center, the parabolic reflector, and the cross section in the quiet zone in the three-dimensional coordinate system, the incident defocusing equation of the feed phase center is established. Input the coordinates of multiple preset observation points on the cross section in the quiet zone into the incident defocusing equation, and calculate and output the estimated coordinate value of the feed phase center. The feed phase center is calibrated and positioned according to the estimated coordinates so that the coordinates of the feed phase center coincide with the focal point of the parabolic reflector.

2. The method of claim 1, wherein, The process of establishing the incident defocusing equation for the feed phase center based on the spatial relationship between the feed phase center, the parabolic reflector, and the mid-section of the quiet zone in a three-dimensional coordinate system includes: Based on the relationship between the coordinates of the observation point on the cross section in the quiet zone and the focal length of the parabolic reflector, the analytical equation of the parabolic reflector is established. Based on the set relationship of the incident ray, reflected ray, and normal, determine the geometric constraints of the feed phase center point, reflection point, and observation point in the three-dimensional coordinate system; Based on the phase measurement data corresponding to the observation point, the combined analytical equation and geometric constraints are derived and simplified to obtain the incident defocusing equation.

3. The method of claim 2, wherein, The analytical equation is established by the following formula: Wherein, ( x , y , z ) is the coordinate of the point to be observed in the cross section in the dead zone; F is the focal length.

4. The method of claim 3, wherein, The incident defocusing equation is established by the following formula: Wherein, ( x 0, y 0, z 0) is the coordinate of the phase center point of the defocused feed source; ( x r , y r , z r ) is the coordinate of the reflection point on the reflecting surface; Δ φ is the absolute phase difference; λ is the wavelength corresponding to the working frequency; x m is the x-axis coordinate value of the quiet zone test position.

5. The method of claim 1, wherein, The step of inputting the coordinates of multiple preset observation points on the cross section in the quiet zone into the incident defocusing equation and calculating the output to obtain the coordinate estimate of the feed phase center includes: Acquire the phase measurement data and coordinate values ​​corresponding to each preset observation point; The phase measurement data and coordinate values ​​are substituted into the incident defocusing equation for numerical calculation, and the estimated coordinates of the feed phase center are output.

6. The method of claim 1, wherein, The preset observation points include the center point on the cross section in the quiet zone, the two endpoints of the horizontal section, and the two endpoints of the vertical section.

7. A device for fast positioning of the phase center of a compact range feed characterized in that, The device includes: The first modeling unit is used to establish a three-dimensional coordinate system with the vertex of the parabolic reflector as the origin and the focal line of the parabolic reflector as the X-axis, based on the positional relationship between the parabolic reflector and the feed phase center. The second modeling unit is used to establish the incident defocusing equation of the feed phase center based on the spatial positional relationship between the feed phase center, the parabolic reflector and the cross section in the quiet zone in the three-dimensional coordinate system. The calculation unit is used to input the coordinates of multiple preset observation points on the cross section in the quiet zone into the incident defocusing equation, and calculate and output the estimated coordinate value of the feed phase center. The positioning unit is used to calibrate and position the feed phase center according to the coordinate estimation value, so that the coordinates of the feed phase center coincide with the focal point of the parabolic reflector.

8. A computer device, comprising: The computer device includes a memory and a processor. The memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory to implement the steps of the method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, implements the steps of the method described in any one of claims 1-6.

10. A computer program product, characterised in that, A computer program comprising computer program elements which, when executed by a processor, implement the steps of the method according to any one of claims 1 to 6.

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