Data fusion algorithm for low-altitude radar target and wireless detection target

Abstract

According to the data fusion algorithm for the low-altitude radar target and the wireless detection target, the fact that in target information given by a low-altitude radar device and a wireless detection device, only target orientation can enable the low-altitude radar device and the wireless detection device to generate direct relevance is fully utilized, and whether data of the two detection devices are the same target or not is judged through target orientation data. According to the invention, the 0-360-degree detection orientation of the wireless detection device is used as the detection range, after the initial detection orientation is selected, one detection subarea is defined every 15 degrees, and the wireless monitoring target is distributed, so that the characteristic of high target data precision of the low-altitude radar target is fully utilized; the target data of the low-altitude radar target is converted into the target data with the wireless detection device as the center, and the precision of the target data is not changed, so that the difficult problem that whether the target is the same target or not is difficult to judge due to the difference of the target information acquired by the low-altitude radar device and the wireless detection device is solved; and data fusion of a low-altitude radar target and a wireless detection target is realized.

Description

Technical Field

[0001] The present invention relates to the field of target detection, and in particular to a data fusion algorithm for low-altitude radar targets and wireless detection targets. Background Art

[0002] At present, in the field of low-altitude surveillance, the sensors used for drone target detection are mainly low-altitude radar equipment and wireless detection equipment. Low-altitude radar equipment is an active detection device, that is, it detects targets by actively receiving and sending electromagnetic wave signals, that is, it is used to detect low-altitude radar targets; wireless detection equipment is a passive detection device, that is, it passively receives the radio broadcast used by the target for communication and analyzes and filters the radio signals to obtain the target type and target location information, and is used to detect wireless detection targets (AOA).

[0003] According to the working principles of the two sensors, we will obtain two different types of target information: low-altitude radar equipment can obtain relatively accurate target location information including target direction, distance and altitude; wireless detection equipment can obtain the frequency band used by the target communication and relatively rough location information, namely target direction. Due to the differences in the target information obtained by the two detection devices, it becomes a problem that must be solved to determine whether the data from the two detection devices are the same target.

[0004] The target data provided by low-altitude radar equipment include direction, distance, altitude, speed and movement trend (i.e. approaching or moving away); the target data provided by wireless detection equipment include the frequency band used for target communication and target direction; however, since wireless detection equipment is a passive detection equipment, the target direction provided by it is inevitably affected by the surrounding environment of the equipment installation, so the accuracy of its target direction is low, and its accuracy is generally within 10 ... About 7.5°.

[0005] Among the target information provided by the two devices, only the target direction can make the two types of data directly correlated; therefore, the problem of determining whether the data from the two detection devices are for the same target can only be solved through the target direction data.

[0006] The two detection devices have two main common features: the detection range of both detection devices is 0-360° and both detection devices need to be installed at a high place with no obstructions in the surrounding area.

[0007] The feasibility of data fusion of the two detection devices is mainly due to the high accuracy of the target data provided by the low-altitude radar device. The target data of the low-altitude radar device is converted into target data centered on the wireless detection device through the installation position relationship of the two devices, and the target data accuracy remains unchanged. Summary of the invention

[0008] In response to the above-mentioned technical problems in the related technology, the present invention proposes a data fusion algorithm for low-altitude radar targets and wireless detection targets based on deep learning and transfer learning, which can overcome the above-mentioned shortcomings of the prior art.

[0009] To achieve the above technical objectives, the technical solution of the present invention is implemented as follows: The data fusion algorithm for low-altitude radar targets and wireless detection targets described in the present invention comprises the following steps: S1: Set the 0°--360° detection direction of the wireless detection device as the detection range, set the starting detection direction N, and the detection time period for data analysis; if N has no value, it is initialized to 0 by default; S2: In the detection range, from N° to 360°, the detection area is divided into M detection areas with a 15° interval, M=[(360-N) / 15], where M is an integer; “[]” is a general mathematical rounding symbol; S3: Select several wireless detection targets, randomly distribute them to all detection partitions according to their positions, and unify and sort the data of all wireless detection targets within the detection time period; S4: using a low-altitude radar device to monitor and determine a low-altitude radar target, and converting the data of the low-altitude radar target into target position information centered on the wireless detection device; S5: traverse all detection partitions, and use the target position information converted in S4 to determine whether the low-altitude radar target is located in a detection partition; if so, continue to S6; otherwise, it means that the low-altitude radar target is invalid and needs to be re-determined, and return to S4; S6: Continue to determine whether the low-altitude radar target is located in only one detection partition; if so, record the detection partition where the low-altitude radar target is located as the comparison area, and continue to S7; otherwise, increase the value of N by 7.5 and return to S2; S7: Determine whether there is more than one wireless detection target in the comparison area; if so, continue to S8; if not, increase the value of N by 7.5 and return to S2; S8: Assign the communication frequency band data of all wireless detection targets in the comparison area to the low-altitude radar target, and assign the target type to the UAV, thereby completing the data fusion of the low-altitude radar target and the wireless detection target.

[0010] Preferably, the detection time period is preferably 10-20 seconds, depending on actual needs.

[0011] Preferably, in S2, the number of the wireless detection targets is preferably 2-24.

[0012] Preferably, in S2, 0≦N≦345, 1≦M≦24, that is, at least one detection partition is divided.

[0013] Preferably, in S2, N°=0° or 7.5°, M=[(360-N) / 15], M is an integer, that is: N=0, M=24; N=7.5, M=23; "[]" is an integer symbol. The meaning is that the 0°--360° detection range of the wireless detection device is preferably divided into 24 detection partitions starting from 0° and 15° each. If N=7.5, then M=23; similarly, N=15, M=23; N=22.5, M=22, and so on.

[0014] Preferably, if Figure 1 As shown, the specific conversion method of S4 is: S4.1: The installation location of the low-altitude radar equipment is recorded as point A, the installation location of the wireless detection equipment is recorded as point B, and the location of the low-altitude radar target is recorded as point C. Connect points A, B, and C to obtain line segments AC, AB, and BC respectively; S4.2: Low-altitude radar equipment, obtain the azimuth α and distance Dac of the low-altitude radar target point C relative to the low-altitude radar equipment point A. The azimuth α is the angle between the line segment AC and the initial detection azimuth, and Dac is the length of the line segment AC, that is, the distance from the target to the equipment; The angle between line segment AC and line segment AB is denoted as β, which represents the angle of transformation that needs to be made by point C of the low-altitude radar target relative to point A of the low-altitude radar target; The angle between line segment BC and line segment AB is denoted as γ, which represents the transformation angle that point C of the low-altitude radar target needs to make relative to point B of the wireless detection device; The angle between line segment BC and the initial detection azimuth is denoted as δ, which represents the supplementary angle of the target position azimuth of point C of the low-altitude radar target relative to point B of the wireless detection device, that is, the target azimuth is equal to 360-δ; S4.3: Obtain the distance Dab and azimuth ε of point B of the wireless detection device relative to point A of the low-altitude radar device, where Dab is the length of line segment AB - the distance between the wireless detection device and the low-altitude radar device; ε represents the standard azimuth value of point B of the wireless detection equipment relative to point A of the low-altitude radar equipment; S4.4: Because α+β +γ +δ = 180, γ +δ = 360 -ε, so β ​​= ε-α -180, the units are °; S4.5: According to the following formula, the azimuth η and distance Dbc of the low-altitude radar target relative to the wireless detection device are finally obtained; (Formula 1); (Formula 2); (Formula 3); S4.6: The azimuth η and distance Dbc of the low-altitude radar target relative to the wireless detection device, that is, the target position information centered on the wireless detection device obtained by conversion.

[0015] The beneficial effects of the present disclosure: fully utilizing the target information provided by low-altitude radar equipment and wireless detection equipment, only the target azimuth can make the two directly correlated, and through the target azimuth data to determine whether the data of the two detection equipment is the same target. The present disclosure uses the 0°--360° detection azimuth of the wireless detection equipment as the detection range, and after selecting the starting detection azimuth, a detection partition is demarcated every 15° and a wireless monitoring target is assigned, making full use of the high precision of the target data of the low-altitude radar target, converting the target data of the low-altitude radar target into target data centered on the wireless detection equipment, and the target data accuracy remains unchanged, solving the thorny problem of difficulty in judging whether it is the same target due to the difference in the target information obtained by the low-altitude radar equipment and the wireless detection equipment, and realizing the data fusion of the low-altitude radar target and the wireless detection target. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A graphic illustration of the conversion of data of low-altitude radar targets in S4 into target location information centered on the wireless detection device. DETAILED DESCRIPTION

[0018] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0019] like Figure 1 As shown, in order to facilitate understanding of the above technical solutions of the present invention, the above technical solutions of the present invention are described in detail below through specific usage methods.

[0020] The data fusion algorithm for low-altitude radar targets and wireless detection targets described in the present invention comprises the following steps: S1: Set the 0°--360° detection direction of the wireless detection device as the detection range, set the starting detection direction N, and the detection time period for data analysis; if N has no value, it is initialized to 0 by default; S2: In the detection range, from N° to 360°, the detection area is divided into M detection areas with a 15° interval, M=[(360-N) / 15], where M is an integer; “[]” is a general mathematical rounding symbol; S3: Select several wireless detection targets, randomly distribute them to all detection partitions according to their positions, and unify and sort the data of all wireless detection targets within the detection time period; S4: using a low-altitude radar device to monitor and determine a low-altitude radar target, and converting the data of the low-altitude radar target into target position information centered on the wireless detection device; S5: traverse all detection partitions, and use the target position information converted in S4 to determine whether the low-altitude radar target is located in a detection partition; if so, continue to S6; otherwise, it means that the low-altitude radar target is invalid and needs to be re-determined, and return to S4; S6: Continue to determine whether the low-altitude radar target is located in only one detection partition; if so, record the detection partition where the low-altitude radar target is located as the comparison area, and continue to S7; otherwise, increase the value of N by 7.5 and return to S2; S7: Determine whether there is more than one wireless detection target in the comparison area; if so, continue to S8; if not, increase the value of N by 7.5 and return to S2; S8: Assign the communication frequency band data of all wireless detection targets in the comparison area to the low-altitude radar target, and assign the target type to the UAV, thereby completing the data fusion of the low-altitude radar target and the wireless detection target.

[0021] In a specific embodiment, the detection time period is preferably 10-20 seconds, depending on actual needs.

[0022] In a specific embodiment, in S2, the number of the wireless detection targets is preferably 2-24.

[0023] In a specific embodiment, in S2, 0≦N≦345, 1≦M≦24, that is, at least one detection partition is divided.

[0024] In a specific embodiment, in S2, N°=0° or 7.5°, M=[(360-N) / 15], M is an integer, that is: N=0, M=24; N=7.5, M=23; "[]" is an integer symbol. The meaning is that the 0°--360° detection range of the wireless detection device is preferably divided into 24 detection partitions of 15° starting from 0°. If N=7.5, then M=23; similarly, N=15, M=23; N=22.5, M=22, and so on.

[0025] In a specific embodiment, Figure 1 As shown, the specific conversion method of S4 is: S4.1: The installation location of the low-altitude radar equipment is recorded as point A, the installation location of the wireless detection equipment is recorded as point B, and the location of the low-altitude radar target is recorded as point C. Connect points A, B, and C to obtain line segments AC, AB, and BC respectively; S4.2: Low-altitude radar equipment, obtain the azimuth α and distance Dac of the low-altitude radar target point C relative to the low-altitude radar equipment point A. The azimuth α is the angle between the line segment AC and the initial detection azimuth, and Dac is the length of the line segment AC, that is, the distance from the target to the equipment; The angle between line segment AC and line segment AB is denoted as β, which represents the angle of transformation that needs to be made by point C of the low-altitude radar target relative to point A of the low-altitude radar target; The angle between line segment BC and line segment AB is denoted as γ, which represents the transformation angle that point C of the low-altitude radar target needs to make relative to point B of the wireless detection device; The angle between line segment BC and the initial detection azimuth is denoted as δ, which represents the supplementary angle of the target position azimuth of point C of the low-altitude radar target relative to point B of the wireless detection device, that is, the target azimuth is equal to 360-δ; S4.3: Obtain the distance Dab and azimuth ε of point B of the wireless detection device relative to point A of the low-altitude radar device, where Dab is the length of line segment AB - the distance between the wireless detection device and the low-altitude radar device; ε represents the standard azimuth value of point B of the wireless detection equipment relative to point A of the low-altitude radar equipment; S4.4: Because α+β +γ +δ = 180, γ +δ = 360 -ε, so β ​​= ε-α -180, the units are °; S4.5: According to the following formula, the azimuth η and distance Dbc of the low-altitude radar target relative to the wireless detection device are finally obtained; (Formula 1); (Formula 2); (Formula 3); S4.6: The azimuth η and distance Dbc of the low-altitude radar target relative to the wireless detection device, that is, the target position information centered on the wireless detection device obtained by conversion.

[0026] In summary, with the help of the above technical scheme of the present invention, full use is made of the target information given by the low-altitude radar equipment and the wireless detection equipment. Only the target azimuth can make the two directly correlated, and the target azimuth data is used to determine whether the data of the two detection equipment are the same target. The present invention uses the 0°--360° detection azimuth of the wireless detection equipment as the detection range, and after selecting the starting detection azimuth, a detection partition is demarcated every 15° and a wireless monitoring target is assigned. The high accuracy of the target data of the low-altitude radar target is fully utilized, and the target data of the low-altitude radar target is converted into target data centered on the wireless detection equipment. The accuracy of the target data remains unchanged, which solves the thorny problem of difficulty in judging whether it is the same target due to the difference in the target information obtained by the low-altitude radar equipment and the wireless detection equipment, and realizes the data fusion of the low-altitude radar target and the wireless detection target.

[0027] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A data fusion algorithm for low-altitude radar targets and wireless detection targets, characterized in that: The following steps are involved: S1: Set the 0°--360° detection direction of the wireless detection device as the detection range, set the starting detection direction N, and the detection time period for data analysis; if N has no value, it is initialized to 0 by default; S2: In the detection range, from N° to 360°, the detection area is divided into M detection areas with a 15° interval, M=[(360-N) / 15], where M is an integer; "[]" is a general mathematical rounding symbol; S3: Select several wireless detection targets, randomly distribute them to all detection partitions according to their positions, and unify and sort the data of all wireless detection targets within the detection time period; S4: using a low-altitude radar device to monitor and determine a low-altitude radar target, and converting the data of the low-altitude radar target into target position information centered on the wireless detection device; S5: traverse all detection partitions, and use the target position information converted in S4 to determine whether the low-altitude radar target is located in a detection partition; if so, continue to S6; otherwise, it means that the low-altitude radar target is invalid and needs to be re-determined, and return to S4; S6: Continue to determine whether the low-altitude radar target is located in only one detection zone; If yes, the detection partition where the low-altitude radar target is located is recorded as the comparison area, and S7 is continued; otherwise, the value of N is increased by 7.5, and S2 is returned again; S7: Determine whether there is more than one wireless detection target in the comparison area; if so, continue to S8; if not, increase the value of N by 7.5 and return to S2; S8: Assign the communication frequency band data of all wireless detection targets in the comparison area to the low-altitude radar target, and assign the target type to the UAV, thereby completing the data fusion of the low-altitude radar target and the wireless detection target.

2. The data fusion algorithm according to claim 1, characterized in that: The detection time period is 10-20 seconds.

3. The data fusion algorithm according to claim 1, characterized in that: In S2, 0≦N≦345, 1≦M≦24.

4. The data fusion algorithm according to claim 1, characterized in that: In S2, the number of the wireless detection targets is 2-24.

5. The data fusion algorithm according to claim 1, characterized in that: The specific conversion method of S4 is: S4.1: The installation location of the low-altitude radar equipment is recorded as point A, the installation location of the wireless detection equipment is recorded as point B, and the location of the low-altitude radar target is recorded as point C. Connect points A, B, and C to obtain line segments AC, AB, and BC respectively; S4.2: Low-altitude radar equipment, obtain the azimuth α and distance Dac of the low-altitude radar target point C relative to the low-altitude radar equipment point A. The azimuth α is the angle between the line segment AC and the initial detection azimuth, and Dac is the length of the line segment AC, that is, the distance from the target to the equipment; The angle between line segment AC and line segment AB is denoted as β, which represents the angle of transformation that needs to be made by point C of the low-altitude radar target relative to point A of the low-altitude radar target; The angle between line segment BC and line segment AB is denoted as γ, which represents the transformation angle that point C of the low-altitude radar target needs to make relative to point B of the wireless detection device; The angle between line segment BC and the initial detection azimuth is denoted as δ, which represents the supplementary angle of the target position azimuth of point C of the low-altitude radar target relative to point B of the wireless detection device, that is, the target azimuth is equal to 360-δ; S4.3: Obtain the distance Dab and azimuth ε of point B of the wireless detection device relative to point A of the low-altitude radar device, where Dab is the length of line segment AB - the distance between the wireless detection device and the low-altitude radar device; ε represents the standard azimuth value of point B of the wireless detection equipment relative to point A of the low-altitude radar equipment; S4.4: Since α+β +γ +δ = 180, γ +δ = 360 -ε, so β ​​= ε-α -180; S4.5: According to the following formula, the azimuth η and distance Dbc of the low-altitude radar target relative to the wireless detection device are finally obtained; (Formula 1); (Formula 2); (Formula 3); S4.6: The azimuth η and distance Dbc of the low-altitude radar target relative to the wireless detection device, that is, the target position information centered on the wireless detection device obtained by conversion.

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