Track establishing device, radar device, and target detection program

Abstract

To provide a track establishing device, a radar device, and a target detection program capable of precisely detecting a target.SOLUTION: A track establishing device includes a plot data creation section, a storage section, a track estimation section, and a target detection section. The plot data creation section creates plot data showing a detection point detected as a target candidate from a reception signal received by an antenna. The storage section stores plot data created by the plot data creation section in a storage device. The track estimation section estimates a track in which a detection point shown by plot data created by the plot data creation section and a detection point shown by past time-series plot data stored in the storage device are connected under a condition corresponding to a target. The target detection section outputs a detection point estimated as a track as a target when a detection point estimated as a track by the track estimation section satisfies a target reference.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE The present invention relates to a track establishment device, a radar device, and a target detection program. [Background technology]

[0002] Conventionally, there is a radar device that uses radio waves as a system for detecting moving objects (hereinafter also referred to as targets) such as flying objects approaching from afar. In recent years, as the moving speed of targets has been increasing, it has become necessary for the radar device to detect targets at long distances and early. In order to detect targets at long distances and early, the basic performance of the radar device has been improved, such as by increasing the size and output, and research has been conducted on target detection technology with low signal-to-noise ratio and target trajectory extraction technology.

[0003] As a conventional technique, a radar device has been proposed that identifies the target's trajectory using multiple plot data obtained by multiple scans. For example, a conventional radar device creates a hypothesis of the trajectory for a detection point by a movement vector calculated from the plot data obtained by a scan and the plot data obtained by the next scan. However, since the above-mentioned conventional radar device calculates the movement vector from the amount of change in distance, if the detection point cannot be detected accurately in each scan, the target cannot be detected accurately, and there is a problem that it is difficult to respond to the target's sharp turns or irregular trajectory. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-174004 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in consideration of the above problems, and has an object to provide a track establishment device, a radar device, and a target detection program that are capable of detecting targets with high accuracy. [Means for solving the problem]

[0006] According to an embodiment, a track establishment device has a plot data creation unit, a storage unit, a track estimation unit, and a target detection unit. The plot data creation unit creates plot data indicating detection points to be detected as target candidates from a signal received by an antenna. The storage unit stores the plot data created by the plot data creation unit in a storage device. The track estimation unit estimates a track by connecting detection points indicated by the plot data created by the plot data creation unit and detection points indicated by past time-series plot data stored in the storage device under conditions according to the target. The target detection unit outputs the detection point estimated as the track by the track estimation unit as the target when the detection point satisfies a criterion for setting the detection point as the target. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram showing an example of the configuration of a radar device including a track establishing device according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing an example of plot data of amplitude in a scan range based on a received signal obtained by a track establishment device according to an embodiment in one scan operation. [Diagram 3] FIG. 3 is a diagram illustrating an example of plot data indicating detection points detected from plot data of amplitudes in a scan range by the track establishment device according to the embodiment. [Figure 4] FIG. 4 is a diagram showing an example of setting an assumed position gate for a detection point indicated by plot data created by a track establishment device according to the embodiment. [Diagram 5] FIG. 5 is a diagram showing a first example of a track estimation result by a track estimation unit in the track establishment device according to the embodiment. [Figure 6] FIG. 6 is a diagram showing a second example of a track estimation result by the track estimation unit in the track establishment device according to the embodiment. [Figure 7]FIG. 7 is a flowchart for explaining an example of operations up to target detection by the track establishment device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment will be described with reference to the drawings. FIG. 1 is a block diagram showing an example of the configuration of a radar device 1 including a track establishing device 12 according to an embodiment of the present invention. The radar device 1 is a device that detects moving objects (hereinafter referred to as targets) including flying objects such as flying objects, aircraft, and drones, by using radio waves. The radar device 1 detects objects present in a predetermined scan range by scanning the predetermined range (scan range) using radio waves. The radar device 1 according to this embodiment detects targets approaching a predetermined radar position. As a specific example, the radar device 1 detects targets, which are objects approaching a specific facility (hereinafter referred to as a target facility), by setting the radar position at or near the target facility.

[0009] 1, the radar device 1 has an antenna 11 and a track establishing device 12. The radar device 1 may have a configuration in which the track establishing device 12 acquires a signal received by the antenna 11. The radar device 1 may have the antenna 11 and the track establishing device 12 configured integrally, or may have the antenna 11 and the track establishing device 12 installed at separate locations.

[0010] Furthermore, the radar device 1 may be configured such that the antenna 11 is installed on an air vehicle (moving object) such as a UAV (unmanned aerial vehicle), and the track establishment device 12 acquires a received signal from the antenna 11. The radar device 1 may also be configured such that the antenna 11 and the track establishment device 12 are installed on a moving object such as an air vehicle, and the track establishment device 12 outputs information such as a target detection result to an external device provided at a predetermined position.

[0011] Antenna 11 transmits and receives radio waves. Antenna 11 transmits radio waves for detecting targets and receives reflected waves of the transmitted radio waves. Antenna 11 is configured to transmit radio waves to a predetermined scan range. Objects present within the scan range reflect the radio waves transmitted from antenna 11. Antenna 11 receives radio waves including reflected waves reflected by objects present within the scan range.

[0012] That is, the antenna 11 receives radio waves including reflected waves from objects present within a predetermined scan range as a received signal in one scanning operation. The antenna 11 outputs a received signal that is a result of scanning the scan range to the track establishment device 12. The antenna 11 performs a scanning operation at predetermined intervals to output a received signal obtained by scanning the scan range at predetermined intervals to the track establishment device 12.

[0013] The track establishment device 12 acquires a signal received by the antenna 11. The track establishment device 12 acquires a received signal that is a result of scanning a predetermined scan range at a predetermined interval. The track establishment device 12 detects detection points (plots) that seem to be moving objects in the received signal from the antenna 11. The track establishment device 12 creates plot data indicating the detection points for each scan. The track establishment device 12 estimates the track (trajectory) of each detection point from the plot data of multiple scans. The track establishment device 12 determines whether or not the detection point is a target to be detected based on the estimated track of the detection point. If the track establishment device 12 determines that the detection point is a target based on the estimated track, it outputs that a target has been detected.

[0014] The track establishment device 12 is composed of a computer having a processor, memory, and an interface. The computer as the track establishment device 12 executes various processes by the processor executing programs stored in the memory (storage device). For example, the computer as the track establishment device 12 may install a target detection program for executing the processes described below in the memory, and the processor may execute the target detection program to realize the operations described below.

[0015] The track establishment device 12 has storage devices such as a memory for storing time-series plot data (described later) and a memory for storing setting information. The track establishment device 12 has an interface for acquiring a received signal from the antenna 11. The track establishment device 12 may also have one or more circuits for processing the received signal from the antenna 11.

[0016] In the exemplary configuration shown in FIG. 1, the track establishing device 12 has functions such as an interface unit 120, a plot data creation unit 121, a plot data storage unit (storage unit) 122, a track estimation unit 123, and a track determination unit (target detection unit) . The interface unit 120, plot data creation unit 121, plot data storage unit 122, track estimation unit 123, and track determination unit 124 are functions realized by a computer equipped with a processor, memory, and interface as the track establishment device 12 executing a program. Some or all of the functions of the interface unit 120, the plot data creation unit 121, the plot data storage unit 122, the track estimation unit 123, and the track determination unit 124 may be realized by hardware such as a circuit.

[0017] The interface unit 120 acquires a signal received by the antenna 11 from the antenna 11. The interface unit 120 supplies the signal received by the antenna 11 to the plot data creation unit 121. The interface unit 120 may include a signal circuit that processes the signal received from the antenna 11.

[0018] The plot data creation unit 121 acquires a signal received by the antenna 11 indicating information indicating a position in three-dimensional space and the amplitude of radio waves via the interface unit 120. The plot data creation unit 121 detects (extracts) detection points that are candidates for objects in the scan range based on the reception signal received by the antenna 11 acquired by the interface unit 120. The plot data creation unit 121 creates plot data indicating detection points detected in the scan range for each scan.

[0019] For example, the plot data creation unit 121 generates amplitude data indicating the amplitude value of the received signal at each point in space in a scan range indicated by distance, azimuth angle, and elevation angle. The plot data creation unit 121 generates amplitude plot data by plotting the amplitude value of each point in the scan range. The plot data creation unit 121 compares the amplitude value of each point in the scan range with a threshold value for plot detection. The plot data creation unit 121 determines a point where the amplitude value exceeds the threshold value for plot detection as a detection point. The plot data creation unit 121 creates data indicating the detection points in the scan range as plot data. The plot data creation unit 121 supplies the created plot data to the plot data storage unit 122 and the track estimation unit 123.

[0020] Fig. 2 is a diagram showing an example of plot data of amplitude at each point in a scan range based on a received signal in the scan range obtained by one scan operation. Fig. 3 is a diagram showing an example of plot data showing detection points detected from the plot data of amplitude shown in Fig. 2. The example shown in FIG. 2 shows the amplitude values ​​of each point in the scan range, which is a three-dimensional space defined by the distance, azimuth angle, and elevation angle with respect to the radar position R (see FIG. 4) serving as the reference position.

[0021] As shown in Fig. 3, the plot data creation unit 121 compares the amplitude value of each point shown in Fig. 2 with a plot detection threshold value to determine whether each point is a detection point that is a candidate for an object (target) (presence or absence of detection). For example, the plot data creation unit 121 detects points in the scan range shown in Fig. 2 whose amplitude exceeds the plot detection threshold value as detection points. The plot data creation unit 121 sets data indicating the distance, azimuth angle, elevation angle, and amplitude for all detection points detected in the scan range by one scanning operation as plot data for one scan.

[0022] The plot data storage unit 122 stores the plot data created by the plot data creation unit 121 in chronological order in a storage device (memory) provided in the track establishment device 12. For example, the plot data storage unit 122 assigns identification information (e.g., an ID) indicating a time series to the plot data for each scan created by the plot data creation unit 121 and stores the data in the storage device. In addition, the plot data storage unit 122 transmits the past plot data stored in the storage device to the track estimation unit 123.

[0023] The track estimation unit 123 executes a track estimation process to estimate a track of a detection point that is a target candidate based on multiple pieces of chronologically ordered plot data. The track estimation unit 123 acquires plot data (current plot data) created by the plot data creation unit 121. The track estimation unit 123 also acquires past plot data in chronological order stored by the plot data storage unit 122. The track estimation unit 123 estimates a track of the detection point based on the current plot data created by the plot data creation unit 121 and the past plot data in chronological order stored by the plot data storage unit 122.

[0024] The track estimation unit 123 sets an assumed position gate as a condition according to the target for a detection point (past detection point) indicated by past plot data. The track estimation unit 123 judges whether or not a detection point (current detection point) indicated by current plot data is within the assumed position gate. If the current detection point is within the assumed position gate for the past detection point, the track estimation unit 123 estimates a track connecting the past detection point and the current detection point within the assumed position gate for that past detection point.

[0025] The track estimation unit 123 sets an assumed position gate based on an assumed speed and an assumed turning angle set for a target moving body. For example, the track estimation unit 123 includes a setting storage unit 123a that stores, as setting information, an assumed speed and an assumed turning angle set corresponding to a target to be detected.

[0026] FIG. 4 is a diagram showing an example of setting an assumed position gate G with respect to a detection point P indicated by plot data. As shown in Fig. 4, the assumed position gate G is set on the assumption that the detection point P, which is a candidate for the target, moves in a direction toward the radar position R. In order to detect a target moving toward the radar position R (or the vicinity of the radar position R), the track estimation unit 123 estimates the track of the detection point, which is a candidate for the target, using the assumed position gate G as shown in Fig. 4. Here, the radar position R is not limited to the installation position of the antenna 11 or the radar device 1 equipped with the antenna 11, and may be set at any position. For example, a target facility located at a position different from the radar device 1 may be set as the radar position.

[0027] The assumed speed is set by assuming the moving speed of a target moving object. In the example shown in Fig. 4, the assumed speed is the moving speed of the target in the direction toward the radar position R that is the reference position. As the assumed speed, an assumed minimum speed (minimum value) Sa and an assumed maximum speed (maximum value) Sb are set. In addition, as the assumed speed, a standard assumed speed Sc corresponding to the target and a speed fluctuation range based on the standard assumed speed Sc may be set.

[0028] The assumed turning angle is set by assuming an angle at which a target moving object moving at an assumed speed can change its moving direction. In the example shown in Fig. 4, the assumed turning angle α is the assumed range of the turning angle of the target moving object when the straight line connecting the detection point P and the radar position R is set as the moving direction. For example, if the target moving object is a flying object, the assumed turning angle α is set based on the assumed turning ability of the flying object during flight.

[0029] The track estimation unit 123 sets a range from the detection point P to the assumed turning angle α with respect to a straight line (straight line PR) passing through the detection point P and the radar position R indicated by the plot data. Furthermore, the track estimation unit 123 sets a range with the minimum value Sa and maximum value Sb of the assumed speed with the detection point P as the base point within the range set by the assumed turning angle α. As a result, the track estimation unit 123 sets the range from the detection point P to the straight line PR at the assumed turning angle α, and defined by the minimum value Sa and maximum value Sb of the assumed speed, as the assumed position gate G.

[0030] 4 shows an example of the assumed position gate G in two dimensions for simplicity, but the assumed position gate G may be set in a three-dimensional space. For example, the track estimation unit 123 sets a three-dimensional assumed position gate G when the detection point P indicated by the plot data is identified as a three-dimensional position.

[0031] The track estimation unit 123 determines whether the detection point P indicated by the latest (current) plot data is present within an assumed position gate for the past detection points stored in the plot data storage unit 122. The track estimation unit 123 estimates the track of the detection point that is a target candidate by connecting, in time series, the detection points that are present within the assumed position gate for the past detection points based on the time series plot data. The track estimation unit 123 supplies the track estimation result estimated by the assumed position gate for the time series detection points to the track determination unit 124.

[0032] The track determination unit 124 determines whether or not to detect a detection point as a target based on the result of estimating the track of the detection point that is a target candidate by the track estimation unit 123. The track determination unit 124 determines whether or not the result of estimating the track by connecting detection points in time series by the track estimation unit 123 is the track of the target. For example, the track determination unit 124 calculates the detection probability based on the amplitude for each detection point connected as the estimated track, and determines whether or not the detection point is a target based on whether or not the cumulative value of the detection probability of each detection point exceeds a threshold value for target determination (a target criterion).

[0033] FIG. 5 is a diagram showing a first example of a track estimation result by the track estimation unit 123 in the track establishment device 12 according to the embodiment. 5, the track estimation unit 123 sets assumed position gates Gn, Gn+1, and Gn+2 for past detection points Pn, Pn+1, and Pn+2. Because detection points Pn+3, Pn+2, and Pn+1 exist within assumed position gates Gn+2, Gn+1, and Gn, respectively, the track estimation unit 123 estimates a track that connects the detection points Pn+3, Pn+2, Pn+1, and Pn in time series.

[0034] 5, the track determination unit 124 calculates the detection probability for each of the detection points Pn+3, Pn+2, Pn+1, and Pn that are connected (estimated) as a track using the assumed position gates Gn, Gn+1, and Gn+2 by the track estimation unit 123. The track determination unit 124 identifies the amplitude of each of the detection points Pn+3, Pn+2, Pn+1, and Pn from the plot data stored in the plot data storage unit 122, and calculates the detection probability of each of the detection points Pn+3, Pn+2, Pn+1, and Pn from the identified amplitude.

[0035] The track determination unit 124 accumulates the detection probability of each of the detection points Pn+3, Pn+2, Pn+1, and Pn that constitute the estimated track, and calculates the accumulated value of the detection probability. The track determination unit 124 performs target determination by comparing the accumulated value of the detection probability of each of the detection points Pn+3, Pn+2, Pn+1, and Pn with a threshold value for target determination. When the accumulated value of the detection probability of each of the detection points Pn+3, Pn+2, Pn+1, and Pn exceeds the threshold value for target determination, the track determination unit 124 determines that the track consisting of these detection points is the track of the target. When the track determination unit 124 determines that the track estimated by the track estimation unit 123 is the track of the target, it outputs that each of the detection points Pn+3, Pn+2, Pn+1, and Pn (or the track of each of the detection points Pn+3, Pn+2, Pn+1, and Pn) has been detected as a target.

[0036] FIG. 6 is a diagram showing a second example of a track estimation result by the track estimation unit 123 in the track establishment device 12 according to the embodiment. In the example shown in FIG. 6, the track estimation unit 123 calculates the detection probability for each detection point (Pn+3, Pn+2, Pn+1, Pn) connected (estimated) as a track using the assumed position gate G.

[0037] In the example shown in Fig. 6, the track estimation unit 123 sets assumed position gates Gn, Gn+1 for past detection points Pn, Pn+1. Detection point Pn+1 exists within the assumed position gate Gn, but no detection point exists within the assumed position gate Gn+1. For this reason, after outputting an estimation result of a track connecting each of the detection points Pn+1, Pn in time series, the track estimation unit 123 does not output an estimation result of a track connecting to the detection point Pn+1. Therefore, the track determination unit 124 does not detect the detection points Pn+1, Pn as targets unless the cumulative value of the detection probability of the detection points Pn+1, Pn exceeds the threshold value for target determination.

[0038] Next, the flow of operations of the track establishing device 12 according to the embodiment will be described. FIG. 7 is a flowchart for explaining an example of operations up to target detection by the track establishing device 12 according to the embodiment. First, in the radar device 1, the antenna 11 scans a scan range at a predetermined scan interval. The antenna 11 supplies the track establishment device 12 with a reception signal indicating the radio waves received each time the antenna 11 scans the scan range.

[0039] The track establishment device 12 acquires the reception signal received by the antenna 11 through the interface unit 120 (step ST11). The reception signal acquired by the interface unit 120 from the antenna 11 is a signal including the amplitude of the received radio wave and information indicating a position in a three-dimensional space that is the scanning range. In the track establishment device 12, the interface unit 120 supplies the reception signal of the antenna 11 to the plot data creation unit 121.

[0040] The plot data creation unit 121 of the track establishment device 12 creates plot data for one scan based on the received signal acquired by the interface unit 120 from the antenna 11 (step ST12). The plot data creation unit 121 detects detection points that are candidates for targets (moving objects) in the scan range from the received signal, which is one scan data, and creates plot data indicating the detection points in the scan range. For example, the plot data creation unit 121 detects points that exceed a threshold for plot detection among the amplitudes of the received signals at each point in the scan range indicated by the distance, azimuth angle, and elevation angle as detection points, and creates plot data indicating the detected detection points.

[0041] When the plot data creation unit of track establishing device 12 creates plot data for one scan, plot data storage unit 122 stores the plot data created by plot data creation unit 121 in a storage device in chronological order (step ST13).

[0042] Furthermore, the track estimation unit 123 of the track establishment device 12 executes a track estimation process based on the plot data for one scan created by the plot data creation unit and the past plot data stored in the plot data storage unit 122 (step ST14-16).

[0043] That is, the track estimation unit 123 of the track establishment device 12 acquires an assumed speed and an assumed turning angle (assumed angle) as setting information corresponding to the target to be detected from the setting storage unit 123a (step ST14). When the track estimation unit 123 acquires the assumed speed and assumed angle corresponding to the target, it sets an assumed position gate based on the assumed speed and assumed turning angle for the past detection point indicated by the past plot data in chronological order (step ST15).

[0044] The track estimation unit 123 judges whether a detection point in the time series including the current detection point exists within an assumed position gate for a past detection point. If the current detection point is within an assumed position gate corresponding to a past detection point, the track estimation unit 123 connects the current detection point to a past detection point that is the starting point of the assumed position gate. If a past detection point connected to the current detection point is within an assumed position gate for a further past detection point, the track estimation unit 123 connects the past detection point connected to the current detection point to the further past detection point. The track estimation unit 123 estimates a group of detection points connected from the current detection point as a track by selecting past detection points in the time series connected from the current detection point (step ST16).

[0045] When the track determination unit 124 of the track establishment device 12 obtains the track estimation result by the track estimation unit 123, it executes a track determination process (track establishment process) that determines whether or not to detect the detection point group estimated as the track as a target (step ST17-21).

[0046] When the track determination unit 124 acquires the results of the estimation of the tracks of the detection points by the track estimation unit 123, it calculates a detection probability for each detection point obtained as the estimation result of the track (step ST17). For example, the track determination unit 124 calculates the detection probability based on the amplitude for each detection point. After calculating the detection probability for each detection point, the track determination unit 124 calculates a cumulative value of the detection probability for each detection point estimated as a track (step S18).

[0047] The track determination unit 124 determines whether or not the detection points constituting the estimated track are the target moving object based on the cumulative value of the detection probability of each detection point estimated as a track (step ST19). For example, the track determination unit 124 determines whether or not the detection points of the estimated track are the target (the estimated track is the track of the target) by comparing the cumulative value of the detection probability of each detection point estimated as a track with a threshold value for target determination (a target criterion).

[0048] The track determination unit 124 determines that each detection point of the estimated track is detected as a target when the cumulative value of the detection probability of each detection point estimated as a track exceeds the threshold for target determination (step ST20, YES).In addition, the track determination unit 124 determines that each detection point of the estimated track is not detected as a target when the cumulative value of the detection probability of each detection point estimated as a track does not exceed the threshold for target determination (step ST20, NO).

[0049] When the track determination unit 124 determines that each detection point of the estimated track is not detected as a target (step ST20, NO), the process returns to step ST20 and repeats the above-mentioned processing.

[0050] Furthermore, when the track determination unit 124 determines that each detection point of the estimated track is detected as a target (step ST20, YES), it outputs that a target has been detected (step ST21). For example, the track establishment device 12 displays information indicating the detection point at which the target was detected on a display device. The track establishment device 12 may also output information indicating the position of the detection point detected as a target as the position of the target present within the scan range. The track establishment device 12 may also output a track consisting of multiple detection points detected as targets as the track of the detected target.

[0051] As described above, the track establishment device of the embodiment creates plot data indicating detection points to be detected as target candidates from the radio waves (received signals) received by the antenna, stores the created plot data in a storage device, estimates a track connecting the detection points of the created plot data and past detection points of the stored plot data using an assumed position gate, and if it determines that the detection point of the estimated track is a target, outputs the detection point of the estimated track as the target.

[0052] As a result, the track establishment device according to the embodiment can accurately detect a target based on a track that connects a detection point detected from a received signal scanned by an antenna over a scan range with a past detection point by an assumed position gate that is set for the past detection point. Also, the track establishment device according to the embodiment sets an assumed position gate according to the assumed speed and assumed turning angle of a target moving object. As a result, the track establishment device can set an assumed position gate according to the movement (flight) capability of the target, and can accurately detect even targets with diverse movement capabilities.

[0053] (Modification) The target moving object to be detected by the track establishment device 12 is assumed to be various moving objects such as flying objects, drones, or aircraft. The speed at which the moving object can move and the angle at which it can turn are considered to differ depending on the type of the moving object. For this reason, the radar device 1 including the track establishment device 12 may be configured to be able to set multiple types of targets. As a modified example of the track establishment device 12, an example in which an assumed speed and an assumed turning angle are set for each type of target in response to multiple types of targets will be described.

[0054] A track establishment device 12 according to such a modified example can be realized by setting an assumed speed and an assumed turning angle for each type of target for multiple types of targets with a configuration similar to that described above. When multiple types of targets are set, the track establishment device 12 only needs to execute the track estimation process and the track determination process described above for each target. In other words, the track establishment device 12 sets an assumed position gate for each type of target. This allows the track establishment device 12 to detect multiple types of targets based on the connection of detection points in time series by the assumed position gates set for each type of target.

[0055] Furthermore, when multiple types of targets are set, the track establishment device 12 may output information indicating the type of target detected from the connection of detection points by the assumed position gate. For example, the track establishment device 12 may output that a flying object has been detected when a target is detected using an assumed position gate set with an assumed speed and assumed turning angle corresponding to a flying object, and may output that an aircraft has been detected when a target is detected using an assumed position gate set with an assumed speed and assumed turning angle corresponding to an aircraft.

[0056] As described above, the track establishment device according to the modified embodiment sets assumed position gates for multiple types of targets according to the assumed speed and assumed turning angle (movement ability) of each target, and estimates tracks for each type of target using the assumed position gates set for each type of target. As a result, the track establishment device described as the modified embodiment can detect multiple types of targets from the received signals scanned multiple times by the antenna.

[0057] Each of the above processes can be executed by several pieces of software. Therefore, the above processes can be easily realized by installing and executing several programs that execute the procedures of the above processes on a computer serving as a track establishment device through a computer-readable storage medium that stores these programs. For example, the computer that constitutes the track establishment device may install the program by downloading the program via a network and storing the downloaded program. Also, the computer that constitutes the track establishment device may install the program by reading the program from various information storage media and storing the read program.

[0058] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0059] 1...Radar device, 11…Antenna, 12...Wake establishment device, 120...Interface section, 121...plot data creation unit, 122...plot data storage unit (storage unit), 123...Wake estimation section, 123a...setting storage section, 124...Track determination unit (target detection unit), P(Pn, Pn+1, Pn+2, Pn+3)…detection point, R…radar position, G (Gn, Gn+1, Gn+2)...Expected position gate.

Claims

1. a plot data generating unit that generates plot data indicating detection points detected as target candidates from a signal received by the antenna; a storage unit that stores the plot data created by the plot data creation unit in a storage device; a track estimation unit that estimates a track by connecting detection points indicated by the plot data created by the plot data creation unit and detection points indicated by the past time-series plot data stored in the storage device under conditions according to a target; a target detection unit that outputs the detection point estimated as the wake by the wake estimation unit as a target when the detection point satisfies a criterion for being a target; A wake establishing device having:

2. The plot data creation unit detects, as a detection point, a point in the received signal where the amplitude exceeds a threshold for plot detection.

2. A track establishing apparatus according to claim 1.

3. the track estimation unit sets an assumed position gate corresponding to an assumed speed of the target for past detection points indicated by past plot data in chronological order, and estimates a track by connecting detection points present within the assumed position gate in chronological order.

2. A track establishing apparatus according to claim 1.

4. The track estimation unit sets the assumed position gate in accordance with an assumed speed and an assumed turning angle of the target.

4. A track establishing apparatus according to claim 3.

5. the target detection unit calculates a detection probability for each detection point estimated as a wake, and when a cumulative value of the calculated detection probability exceeds a threshold value for target detection, outputs the detection point estimated as a wake as a target.

3. A track establishing apparatus according to claim 2.

6. The target detection unit calculates the detection probability based on the amplitude of the detection point.

6. A track establishing apparatus according to claim 5.

7. the flight path estimation unit sets an assumed position gate according to an assumed speed and an assumed turning angle for each of a plurality of types of targets; A track establishing apparatus according to any one of claims 3 to 6.

8. an antenna for receiving radio waves in a predetermined scanning range; a plot data creation unit that creates plot data indicating detection points detected as target candidates from the signal received by the antenna; a storage unit that stores the plot data created by the plot data creation unit in a storage device; a track estimation unit that estimates a track by connecting detection points indicated by the plot data created by the plot data creation unit and detection points indicated by the past time-series plot data stored in the storage device under conditions according to a target; a target detection unit that outputs the detection points estimated as the wake by the wake estimation unit as targets when the detection points satisfy a criterion for setting the detection points as the wake; A radar device having the above structure.

9. On the computer, A process of generating plot data indicating detection points detected as target candidates from the signal received by the antenna; A process of storing the created plot data in a storage device; A process of estimating a track by connecting detection points indicated by the created plot data and detection points indicated by the past time-series plot data stored in the storage device under conditions according to a target; a process of outputting the detection points estimated as the wake as targets when the detection points estimated as the wake satisfy a criterion for setting the detection points as targets; A target detection program that executes the following:

Images