Direction finding method based on normalized power directional diagram

Abstract

The invention discloses a direction finding method based on a normalized power directional diagram, and belongs to the technical field of antennas. According to the method, a digital normalized power directional diagram is utilized, matching calculation is carried out in combination with a small amount of scanning motion, and the angular position of a direction finding target can be rapidly and accurately determined. Meanwhile, polynomial fitting is carried out after a normalized power directional diagram is intercepted based on an orthogonal section group, and directional diagram data is digitalized by fitting parameters, so that the data storage amount is greatly reduced. According to the invention, under the condition that the hardware of the antenna device is not changed, the direction finding precision is ensured, and the direction finding speed is obviously improved.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and more specifically to a direction finding method based on a normalized power pattern. Background Technology

[0002] Radio direction finding, a key technology in modern communication and navigation systems, is widely used in reconnaissance, emergency rescue, and spectrum monitoring. Its core lies in determining the spatial location of a signal source by analyzing the amplitude, phase, or power distribution characteristics of the received signal. Among existing direction finding techniques, parabolic antenna-based methods have been widely used in long-distance, high-precision direction finding tasks due to their high directivity and excellent gain performance. These antennas concentrate energy in a specific direction through reflection structures, significantly improving the signal-to-noise ratio and angular resolution, making them suitable for stable direction finding in complex electromagnetic environments. However, this method also has significant limitations, primarily the response delay caused by mechanical scanning, resulting in less than ideal direction finding speed. Therefore, there is an urgent need for a direction finding method that can significantly improve measurement efficiency while retaining the advantages of directivity and high accuracy. Summary of the Invention

[0003] In view of this, this invention proposes a direction-finding method based on a normalized power pattern. This method utilizes a digitized normalized power pattern, combined with a small amount of scanning motion for matching calculations, to quickly and accurately determine the angular position of the target. Simultaneously, it employs polynomial fitting based on orthogonal tangent groups to extract the normalized power pattern data, thereby significantly reducing data storage requirements. This invention, without altering the antenna hardware, ensures both direction-finding accuracy and significantly improves direction-finding speed.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A direction finding method based on normalized power pattern includes the following steps:

[0006] (1) Obtain normalized power pattern data within the center range of the main lobe of the antenna device;

[0007] (2) Based on the installation method of the antenna device on its mount, two orthogonal tangent groups are determined, defined as tangent one and tangent two, and the normalized power radiation pattern is cut respectively. The obtained cutting line data is subjected to polynomial fitting and the fitting parameters are recorded to generate a digital radiation pattern.

[0008] (3) The antenna device scans along a direction parallel to the first tangent, collects and records the power value output by the signal receiver and the corresponding angle. After the scan is completed, the antenna device rotates to the angle corresponding to the maximum power value.

[0009] (4) The antenna device scans along the direction parallel to the second tangent and at the same time moves back and forth in a certain pattern along the direction parallel to the first tangent to collect and record the power value and corresponding angle output by the signal receiver.

[0010] (5) Match the power value corresponding to the scanning trajectory with the digital direction pattern, determine the angle deviation between the matching starting point and the direction-finding target, and calculate the angular position of the direction-finding target.

[0011] Furthermore, in step (1), the normalized power pattern data within the center range of the main lobe of the antenna device is obtained through electrical test data or simulation data of the antenna device. The pattern data is not limited to the main lobe, and the center range of the main lobe of the antenna device is not less than the half-power beam range of the antenna device.

[0012] Furthermore, the specific method of step (2) is as follows:

[0013] (201) Based on the mounting method of the antenna device on its mount, generate a plane group consisting of the E-axis parallel to the AE mount and the antenna normal, or the Y-axis of the XY mount and the antenna normal. As a cross-section, it simultaneously generates a plane group consisting of the plane formed by the A-axis parallel to the AE mount and the antenna normal, or the plane formed by the X-axis of the XY mount and the antenna normal. As the second section;

[0014] (202) Using the tangent-cut normalized power pattern, the plane is obtained The corresponding set of cutting line data pairs , , , The number of facets corresponding to facet one. The number of data points for the cutting line; simultaneously, using the normalized power pattern of the two-cut plane, the plane is obtained. The corresponding set of cutting line data pairs ; , , This represents the number of facets corresponding to facet two. The number of data points for the cutting line; and The values ​​can be the same. and The values ​​can be the same;

[0015] (203) For each plane respectively and each plane The corresponding data is subjected to a multinomial fit on the set, and the fit is as follows: Where T is the fitting order, These are the fitting coefficients. For the cutting line data pair, obtain with corresponding Group fitting parameters and corresponding Group fitting parameters;

[0016] (204) Group the planes corresponding Group fitting parameters and plane group corresponding The fitted parameters together constitute the digital orientation pattern.

[0017] Furthermore, the specific method of step (3) is as follows:

[0018] (301) Antenna device along parallel The signal is scanned clockwise to collect and record the power value and corresponding angle output by the signal receiver;

[0019] (302) After the scan is completed, the antenna device is rotated to the angle corresponding to the maximum recorded power value.

[0020] Furthermore, the specific method of step (4) is as follows:

[0021] (401) The antenna device is parallel to... Scanning in a clockwise direction, while simultaneously along a direction parallel to The direction of the signal receiver is to reciprocate in a set pattern, and the power value and corresponding angle of the signal receiver output are collected and recorded.

[0022] (402) If the power value in the recorded data is greater than The number of data points is less than Then the antenna device is parallel to Scanning in a counterclockwise direction, while simultaneously along a direction parallel to The direction of the signal reciprocates according to a set pattern, and the power value and corresponding angle output by the signal receiver are collected and recorded; among them, Power threshold, The minimum amount of data required for matching calculations.

[0023] Furthermore, the specific method of step (5) is as follows:

[0024] (501) The intercepted power value is greater than The data and their corresponding angles are denoted as , as test data for matching calculation;

[0025] (502) Construct the evaluation function as follows:

[0026]

[0027] In the formula, The power value on the digital radiation pattern corresponding to the scanning trajectory. This serves as the starting point for the test data during matching calculations. For the digital direction map and The corresponding power value;

[0028] (503) Calculate the evaluation function The smallest value Then the angular position of the direction-finding target for:

[0029]

[0030] In the formula, The starting angle position of the test data during the corresponding matching calculation. for The angular position on the digital orientation map.

[0031] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0032] 1. This invention utilizes a digitized normalized power pattern for matching calculations, which can quickly and accurately determine the angular position of the direction-finding target.

[0033] 2. This invention uses a set of orthogonal tangents to extract the normalized power radiation pattern and then performs polynomial fitting to digitize the radiation pattern data with fitting parameters, which greatly reduces the amount of data storage. Attached Figure Description

[0034] Figure 1 This is a flowchart from an embodiment of the present invention.

[0035] Figure 2 This is a curve fitted using a 6th-order polynomial in an embodiment of the present invention.

[0036] Figure 3 This is a schematic diagram of the motion trajectory of the antenna device performing direction finding in an embodiment of the present invention. Detailed Implementation

[0037] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] A direction finding method based on normalized power pattern includes the following steps, the flowchart of which is shown below. Figure 1 As shown:

[0039] (1) Obtain normalized power pattern data within the center range of the main lobe of the antenna device;

[0040] Normalized power pattern data within the center range of the main lobe of the antenna device can be obtained from electrical test data or simulation data of the antenna device. The pattern data is not limited to the main lobe and can be appropriately narrowed down, generally not less than the half-power beam range of the antenna device. This example selects data from the half-power beam range of the antenna device.

[0041] (2) Based on the installation method of the antenna device on its mount, two orthogonal tangent groups are determined, defined as tangent one and tangent two, and the normalized power radiation pattern is cut respectively. The obtained cutting line data is subjected to polynomial fitting and the fitting parameters are recorded to generate a digital radiation pattern.

[0042] The specific method of step (2) is as follows:

[0043] (201) Based on the mounting method of the antenna device on its mount, generate a plane group consisting of the E-axis parallel to the AE mount and the antenna normal, or the Y-axis of the XY mount and the antenna normal. As a cross-section, it simultaneously generates a plane group consisting of the plane formed by the A-axis parallel to the AE mount and the antenna normal, or the plane formed by the X-axis of the XY mount and the antenna normal. As the second section; in this example, the antenna mount is of type AE. and All values ​​are set to 21 to ensure the symmetry of the cross-section;

[0044] (202) Using the tangent-cut normalized power pattern, the plane is obtained The corresponding set of cutting line data pairs , , , The number of facets corresponding to facet one. The number of data points for the cutting line; simultaneously, using the normalized power pattern of the two-cut plane, the plane is obtained. The corresponding set of cutting line data pairs ; , , This represents the number of facets corresponding to facet two. The number of data points for the cutting line; and The values ​​can be the same. and The values ​​can be the same; in this embodiment, and All values ​​are set to 100 to ensure sufficient data for curve fitting.

[0045] (203) For each plane respectively and each plane The corresponding data is subjected to a multinomial fit on the set, and the fit is as follows: Where T is the fitting order, These are the fitting coefficients. For the cutting line data pair, obtain with corresponding Group fitting parameters and corresponding Group fitting parameters; in this example, the fitting order T=6, and the fitting results are shown in [the image / document / reference]. Figure 2 ;

[0046] (204) Group the planes corresponding Group fitting parameters and plane group corresponding The fitted parameters together constitute the digital orientation pattern.

[0047] (3) The antenna device scans along a direction parallel to the first tangent, collects and records the power value output by the signal receiver and the corresponding angle. After the scan is completed, the antenna device rotates to the angle corresponding to the maximum power value.

[0048] The scanning trajectory is as follows Figure 3 As shown, the specific method is as follows:

[0049] (301) Antenna device along parallel The signal is scanned clockwise to collect and record the power value and corresponding angle output by the signal receiver;

[0050] (302) After the scan is completed, the antenna device is rotated to the angle corresponding to the maximum recorded power value.

[0051] (4) The antenna device scans along the direction parallel to the second tangent and at the same time moves back and forth in a certain pattern along the direction parallel to the first tangent to collect and record the power value and corresponding angle output by the signal receiver.

[0052] The scanning trajectory is as follows Figure 3 As shown, the specific method is as follows:

[0053] (403) The antenna device is parallel to... Scanning in a clockwise direction, while simultaneously along a direction parallel to The direction of the signal receiver is to reciprocate in a set pattern, and the power value and corresponding angle of the signal receiver output are collected and recorded.

[0054] (404) If the power value in the recorded data is greater than The number of data points is less than Then the antenna device is parallel to Scanning in a counterclockwise direction, while simultaneously along a direction parallel to The direction of the signal reciprocates according to a set pattern, and the power value and corresponding angle output by the signal receiver are collected and recorded; among them, Power threshold, The minimum amount of data required for matching calculations.

[0055] (5) Match the power value corresponding to the scanning trajectory with the digital direction pattern, determine the angle deviation between the matching starting point and the direction-finding target, and calculate the angular position of the direction-finding target;

[0056] The specific method is as follows:

[0057] (501) The intercepted power value is greater than The data and their corresponding angles are denoted as , as test data for matching calculation;

[0058] (502) Construct the evaluation function as follows:

[0059]

[0060] In the formula, The power value on the digital radiation pattern corresponding to the scanning trajectory. This serves as the starting point for the test data during matching calculations. For the digital direction map and The corresponding power value;

[0061] (503) Calculate the evaluation function The smallest value Then the angular position of the direction-finding target for:

[0062]

[0063] In the formula, The starting angle position of the test data during the corresponding matching calculation. for The angular position on the digital orientation map.

Claims

1. A direction-finding method based on normalized power pattern, characterized in that, Includes the following steps: (1) Obtain normalized power pattern data within the center range of the main lobe of the antenna device; (2) Based on the installation method of the antenna device on its mount, two orthogonal tangent groups are determined, defined as tangent one and tangent two, and the normalized power radiation pattern is cut respectively. The obtained cutting line data is subjected to polynomial fitting and the fitting parameters are recorded to generate a digital radiation pattern. (3) The antenna device scans along a direction parallel to the first tangent, collects and records the power value output by the signal receiver and the corresponding angle. After the scan is completed, the antenna device rotates to the angle corresponding to the maximum power value. (4) The antenna device scans along the direction parallel to the second tangent and at the same time moves back and forth in a certain pattern along the direction parallel to the first tangent to collect and record the power value and corresponding angle output by the signal receiver. (5) Match the power value corresponding to the scanning trajectory with the digital direction pattern, determine the angle deviation between the matching starting point and the direction-finding target, and calculate the angular position of the direction-finding target.

2. The direction finding method based on normalized power pattern according to claim 1, characterized in that, In step (1), the normalized power pattern data within the center range of the main lobe of the antenna device is obtained through electrical test data or simulation data of the antenna device. The pattern data is not limited to the main lobe, and the center range of the main lobe of the antenna device is not less than the half-power beam range of the antenna device.

3. The direction finding method based on normalized power pattern according to claim 1, characterized in that, The specific method for step (2) is as follows: (201) Based on the mounting method of the antenna device on its mount, generate a plane group consisting of the E-axis parallel to the AE mount and the antenna normal, or the Y-axis of the XY mount and the antenna normal. As a cross-section, it simultaneously generates a plane group consisting of the plane formed by the A-axis parallel to the AE mount and the antenna normal, or the plane formed by the X-axis of the XY mount and the antenna normal. As the second section; (202) Using the tangent-cut normalized power pattern, the plane is obtained The corresponding set of cutting line data pairs , , , The number of facets corresponding to facet one. The number of data points for the cutting line; simultaneously, using the normalized power pattern of the two-cut plane, the plane is obtained. The corresponding set of cutting line data pairs ; , , This represents the number of facets corresponding to facet two. The number of data points for the cutting line; and The values ​​can be the same. and The values ​​can be the same; (203) For each plane respectively and each plane The corresponding data is subjected to a multinomial fit on the set, and the fit is as follows: Where T is the fitting order, These are the fitting coefficients. For the cutting line data pair, obtain with corresponding Group fitting parameters and corresponding Group fitting parameters; (204) Group the planes corresponding Group fitting parameters and plane group corresponding The fitted parameters together constitute the digital orientation pattern.

4. The direction finding method based on normalized power pattern according to claim 3, characterized in that, The specific method for step (3) is as follows: (301) Antenna device along parallel The signal is scanned clockwise to collect and record the power value and corresponding angle output by the signal receiver; (302) After the scan is completed, the antenna device is rotated to the angle corresponding to the maximum recorded power value.

5. The direction finding method based on normalized power pattern according to claim 3, characterized in that, The specific method of step (4) is as follows: (401) The antenna device is parallel to... Scanning in a clockwise direction, while simultaneously along a direction parallel to The direction of the signal receiver is to reciprocate in a set pattern, and the power value and corresponding angle of the signal receiver output are collected and recorded. (402) If the power value in the recorded data is greater than The number of data points is less than Then the antenna device is parallel to Scanning in a counterclockwise direction, while simultaneously along a direction parallel to The direction of the signal reciprocates according to a set pattern, and the power value and corresponding angle output by the signal receiver are collected and recorded; among them, Power threshold, The minimum amount of data required for matching calculations.

6. The direction finding method based on normalized power pattern according to claim 1, characterized in that, The specific method for step (5) is as follows: (501) The intercepted power value is greater than The data and their corresponding angles are denoted as , as test data for matching calculation; (502) Construct the evaluation function as follows: In the formula, The power value on the digital radiation pattern corresponding to the scanning trajectory. This serves as the starting point for the test data during matching calculations. For the digital direction map and The corresponding power value; (503) Calculate the evaluation function The smallest value Then the angular position of the direction-finding target for: In the formula, The starting angle position of the test data during the corresponding matching calculation. for The angular position on the digital orientation map.

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