JP2016017790A - Rader system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rader system that can suppress occurrence of false detection.SOLUTION: A rader system according to an embodiment includes a transmission/receiving part, a detection part, a storage part, and a determination part. The transmission/receiving part transmits and receives electric waves. The detection part detects the position of a detection target based on the electric waves received by the transmission/receiving part. The storage part stores space information on the position and height of an object. The determination part determines the correctness of results of detection based on the position of the detection target and the space information.SELECTED DRAWING: Figure 2

Description

  Embodiments described herein relate generally to a radar apparatus.

  In a radar device that detects a target by radiating a radio wave and receiving a reflected wave of the radiated radio wave, the effect of the clutter generated by the reflected radio wave being reflected on the surrounding environment such as the sea surface and rain, and the noise of the device itself May cause the detection target to be erroneously detected. In the conventional radar apparatus, the occurrence of erroneous detection may not be sufficiently suppressed.

JP 2006-177858 A JP 2001-343455 A JP 2003-43132 A

  The problem to be solved by the present invention is to provide a radar apparatus capable of suppressing the occurrence of erroneous detection of the radar apparatus.

  The radar apparatus according to the embodiment includes a transmission / reception unit, a detection unit, a storage unit, and a determination unit. The transceiver unit transmits and receives radio waves. The detection unit detects the position of the detection target based on the radio wave received by the transmission / reception unit. The storage unit stores spatial information related to the position and height of the object. The determination unit determines the validity of the detection result based on the position of the detection target and the spatial information.

The figure which shows the specific example of the utilization form of the radar apparatus 1 of 1st Embodiment. The functional block diagram which shows the function structure of the radar apparatus 1 of 1st Embodiment. The figure which shows the specific example of the positional relationship of the radar apparatus 1 and the shielding object 5. FIG. The figure which shows the specific example of prospect information. The figure which shows the specific example of non-line-of-sight area information. Schematic which shows the outline | summary of the position detection process in 1st Embodiment. The flowchart which shows the flow of the process in which the radar apparatus 1 of 1st Embodiment detects the object in a detection range. The functional block diagram which shows the function structure of the radar apparatus 1a of 2nd Embodiment. The flowchart which shows the flow of the process in which the radar apparatus 1a of 2nd Embodiment detects the object in a detection range. Schematic which shows the outline | summary of the position detection process in 2nd Embodiment.

  Hereinafter, a radar apparatus according to an embodiment will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram illustrating a specific example of a usage pattern of the radar apparatus 1 according to the first embodiment.
In the figure, reference numeral 1 represents a radar apparatus. The boundary line 2-1 and the boundary line 2-2 represent the boundaries of the detection range of the radar apparatus 1. That is, the detection range of the radar apparatus 1 is an area between the boundary line 2-1 and the boundary line 2-2. The detection targets 3-1 and 3-2 represent targets detected by the radar apparatus 1. The radar apparatus 1 radiates radio waves toward a detection range in order to detect a detection target. The reflected wave 4 represents the radio wave reflected by the detection target 3-1 among the radio waves radiated by the radar apparatus 1. The radar apparatus 1 detects the detection object 3-1 by receiving the reflected wave 4.

  In the figure, a shield 5 is an object that exists in the detection range of the radar device 1 and blocks radio waves radiated from the radar device 1. The shield 5 is, for example, a mountain or a building. Since the radio wave radiated from the radar apparatus 1 is blocked by the shield 5, the radar apparatus 1 cannot detect the detection target 3-2 existing in the area indicated by reference numeral 6 in the detection range. As described above, a region in the detection range where the target cannot be detected by the shielding object 5 is referred to as a non-line-of-sight region. In addition, an area other than the non-line-of-sight area 6 in the detection range is referred to as an in-line area.

FIG. 2 is a functional block diagram illustrating a functional configuration of the radar apparatus 1 according to the first embodiment.
The radar apparatus 1 includes, for example, a storage unit 11, a radio wave transmission / reception unit 12, a position detection unit 13, a non-line-of-sight region calculation unit 14, an erroneous detection determination unit 15, and a data processing unit 16. The storage unit 11 is a storage device such as a read only memory (ROM), a random access memory (RAM), a hard disk drive (HDD), or a flash memory. Each functional unit of the radar apparatus 1 has functions described below, for example, when a processor such as a CPU (Central Processing Unit) connected to the storage unit 11 through a bus executes a program stored in the storage unit 11. Is realized. All or a part of each functional unit of the radar apparatus 1 may be realized by using hardware such as an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA). . The program may be stored in a portable medium such as a flexible disk, a magneto-optical disk, or a CD-ROM, or may be transmitted from another computer via an electric communication line. .

  The storage unit 11 stores in advance information relating to the outlook of the area including the detection range of the own device (hereinafter referred to as “outlook information”). The line-of-sight information is specifically spatial information including the position of the shielding object and information indicating the size of the shielding object such as the width and height. The storage unit 11 stores position information of the own device. For example, when the radar apparatus 1 is fixedly installed at a predetermined location, the position information may be stored in the storage unit 11 in advance as static information. Further, for example, when the radar apparatus 1 is installed on a moving body, the position information may be acquired using a GPS (Global Positioning System) or the like.

  The radio wave transmission / reception unit 12 is configured using devices such as an antenna, a transmitter, a receiver, a transmission / reception switch. As the antenna, for example, an array antenna in which antenna elements are arranged in a matrix may be used. The radar apparatus 1 may be configured to change the directivity by rotating the array antenna itself or controlling the phases of the transmission waves of the plurality of array antennas. The radar apparatus 1 may include a rotatable parabolic antenna. The radar apparatus 1 recognizes the azimuth of the detection target by, for example, processing using a monopulse method.

  The antenna radiates a radio wave for detecting a target toward a detection range of the own device. Further, the antenna receives a radio wave directed to the own device including a radio wave radiated to the detection range and reflected by a detection target. The transmitter generates an electrical signal (hereinafter referred to as “transmission signal”) emitted from the antenna as a radio wave, and performs processing such as modulation and amplification on the generated electrical signal. The receiver performs processing such as noise removal and amplification on the electric signal of the received radio wave output from the antenna (hereinafter referred to as “reception signal”). The duplexer switches between the output of an electrical signal from the transmitter to the antenna and the input of the electrical signal from the antenna to the receiver. The radio wave transmission / reception unit 12 outputs an electric signal of the received radio wave to the position detection unit 13.

  The position detection unit 13 performs signal processing on the received signal, detects a target located in the detection range, and performs position detection processing to acquire a three-dimensional position of the detection target. Specifically, the position detection unit 13 removes unnecessary signals such as clutter from the received signal. The position detection unit 13 calculates the distance from the own device to the detection target based on the time from when the transmission signal is emitted until it is received as the reception signal. The position detection unit 13 acquires the received radio wave intensity distributed in the direction in which the radio wave is radiated based on the intensity and distance of the received signal. The position detection unit 13 detects a detection target based on the degree of change of the received radio wave intensity in the distance direction, the radio wave intensity distribution serving as a threshold, and the like. This is because it is difficult to completely remove unnecessary signals such as clutter and noise from the received signal, and the received radio wave intensity includes the influence of clutter and noise to some extent. The position detection unit 13 calculates the three-dimensional position of the detection target based on the distance from the own device to the detection target and the direction in which the radio wave is emitted. The position detection unit 13 outputs information representing the calculated three-dimensional position of the detection target to the erroneous detection determination unit 15 as detection position information.

  The non-line-of-sight region calculation unit 14 calculates a region that is a non-line-of-sight region in the detection range of the radar device 1 based on the line-of-sight information stored in the storage unit 11 and the position information of the own device. The non-line-of-sight area calculation unit 14 outputs information representing the calculated non-line-of-sight area to the erroneous detection determination unit 15 as non-line-of-sight area information. In addition, when the radar apparatus 1 is fixedly installed at a predetermined location and the line-of-sight information does not change, the non-line-of-sight area information calculated in advance may be stored in the storage unit 11. In this case, the radar apparatus 1 may be configured as an apparatus that does not include the non-line-of-sight area calculation unit 14 by the false detection determination unit 15 acquiring the non-line-of-sight area information from the storage unit 11.

  The erroneous detection determination unit 15 determines whether or not the detection position indicated by the detection position information is located in the non-line-of-sight area based on the non-line-of-sight area information. When it is determined that the detection position is located in the non-line-of-sight region, the erroneous detection determination unit 15 determines that the detection result is invalid and rejects the detection result. On the other hand, when it is determined that the detection position is not located in the non-line-of-sight region, the false detection determination unit 15 outputs the detection result to the data processing unit 16.

  The data processing unit 16 is a functional unit that performs various processes according to the application of the radar apparatus 1 using the detection result. Examples of the process according to the application of the radar apparatus 1 include a process for tracking a detected object and a process for identifying the detected object. The data processing unit 16 may be connected to a display device such as a liquid crystal display or a CRT (Cathode Ray Tube) display, and may be configured to output detection results and results of various processes. In addition, the data processing unit 16 may be connected to an input device such as a mouse or a keyboard, and may be configured to accept input of information necessary for various processes and input the information to the data processing unit 16.

FIG. 3 is a diagram illustrating a specific example of the positional relationship between the radar apparatus 1 and the shielding object 5.
This figure is a view of the radar apparatus 1 and the shield 5 shown in FIG. In the figure, the plane represented by the x-axis and y-axis represents the ground plane. That is, the direction perpendicular to the front surface from the back surface of the paper represents the height direction from the ground. The line-of-sight information of the space having the radar device 1 and the shielding object 5 in the positional relationship shown in FIG. 4 can be expressed as shown in FIG. 4, for example.

FIG. 4 is a diagram illustrating a specific example of the prospect information.
In the figure, the plane represented by the x-axis and y-axis corresponds to the ground plane in FIG. In the figure, each area divided by a broken line represents a unit area obtained by dividing the ground surface by a predetermined distance. The region described in each unit region represents the height of the shield existing in the unit region. That is, the unit area described as “0” in the figure represents that there is no shielding object in the area.

  The unit area indicated by reference numeral 7 in the same figure corresponds to the position of the shield 5 in FIG. That is, the unit area 7 represents that there is a shielding object having a height of “50” in the area. In the figure, for simplicity of explanation, the ground surface is divided so that the shielding object 5 is included in one corresponding unit region. It is good to divide | segment by the unit according to a utilization scene based on a processing capability, resolution, etc.

  In addition, in the figure, for the sake of simplicity, the prospect information is represented as two-dimensional information, but the prospect information may be represented as three-dimensional information. When the line-of-sight information is represented as three-dimensional information, the line-of-sight information is, for example, information represented by a binary value indicating whether or not a shielding object is present in each unit area.

FIG. 5 is a diagram illustrating a specific example of the non-line-of-sight area information.
In the figure, the plane represented by the x-axis and y-axis corresponds to the ground plane in FIG. The non-line-of-sight area information is information divided into unit areas similarly to the line-of-sight information in FIG. The unit area described as “0” in the figure indicates that the area is a line-of-sight area. In addition, the unit area described as “1” in the figure indicates that the area is a non-line-of-sight area. The non-line-of-sight area information shown in the figure is the shielding seen from the radar apparatus 1 based on the line-of-sight information in FIG. 4, the position information of the radar apparatus 1 in FIG. 3, and the direction in which the radar apparatus 1 emits radio waves. It is calculated by setting the area on the back side of the object 5 as the non-line-of-sight area.

FIG. 6 is a schematic diagram showing an outline of the position detection process in the first embodiment.
In the figure, the horizontal axis represents distance. The vertical axis represents the intensity of the reflected wave. Reference numeral 8 represents a distribution of received radio wave intensity acquired by the position detection unit 13 based on the received signal. For each received radio wave, the position detection unit 13 calculates the position (distance from the own device) where the radio wave is reflected based on the time from when the radio wave is emitted until it is received. The position detector 13 obtains the distribution of the received radio wave intensity as shown in the figure by plotting the received radio wave intensity and the position where the radio wave is reflected in association with each other.

The position detection unit 13 detects a target by detecting a radio wave having an intensity exceeding a predetermined threshold in the distribution of received radio wave intensity, and acquires a distance from the own device to the detection target. In the drawing, it is detected RSSI indicating the code 8-1, the distance D ₁ corresponding to the detected RSSI is acquired as the distance to the detection target from the own apparatus.

  The position detection process is performed for each distance unit called a cell in which the distance axis in which the acquired received radio wave intensity is distributed is discretized based on the resolution and processing performance of the radar apparatus 1. In the figure, the distance axis is discretized into cells of distance d.

FIG. 7 is a flowchart illustrating a flow of processing in which the radar apparatus 1 according to the first embodiment detects an object within the detection range.
First, the radio wave transmission / reception unit 12 of the radar apparatus 1 receives radio waves reflected in the direction of the own apparatus among the radio waves radiated from the own apparatus (step S101). The radio wave transmission / reception unit 12 performs processing such as noise removal and amplification on the received signal and outputs the received signal to the position detection unit 13.
The position detection unit 13 performs position detection processing on the received signal, and detects a detection target within the detection range (step S102). The position detection unit 13 determines whether or not a detection target is detected in the position detection process (step S103). When the detection target is not detected (step S103—NO), the radar apparatus 1 ends the process. On the other hand, when the detection target is detected (step S103—YES), the position detection unit 13 acquires the three-dimensional position of the detection target (step S104). The position detection unit 13 outputs information indicating the acquired three-dimensional position of the detection target to the erroneous detection determination unit 15.

  The erroneous detection determination unit 15 acquires information representing the three-dimensional position of the detection target output from the position detection unit 13. Further, the erroneous detection determination unit 15 acquires the non-line-of-sight area information output from the non-line-of-sight area calculation unit 14. The erroneous detection determination unit 15 determines whether or not the non-line-of-sight area indicated by the non-line-of-sight area information includes the three-dimensional position of the detection target (step S105). When the three-dimensional position of the detection target is not included in the non-line-of-sight region (step S105—NO), the erroneous detection determination unit 15 determines that the detection result is valid, and outputs the detection result to the data processing unit 16 ( Step S106). On the other hand, when the three-dimensional position of the detection target is included in the non-line-of-sight region (step S105—YES), the erroneous detection determination unit 15 determines that the detection result is invalid and rejects the detection result (step S107).

  The radar apparatus 1 according to the first embodiment configured as described above has a function of determining whether or not the detected three-dimensional position of the detection target is included in the non-line-of-sight region. By having this function, the radar apparatus 1 determines that the detection target detected in the non-line-of-sight region is a target that should not be detected, and rejects the detection result. Therefore, the radar apparatus 1 according to the first embodiment can suppress the occurrence of erroneous detection.

(Second Embodiment)
FIG. 8 is a functional block diagram illustrating a functional configuration of the radar apparatus 1a according to the second embodiment.
The radar apparatus 1a includes a position detection unit 13a instead of the position detection unit 13, a point of including a line-of-sight region calculation unit 17 instead of the non-line-of-sight region calculation unit 14, and a point that does not include the erroneous detection determination unit 15. Different from the radar apparatus 1 of the first embodiment.

  The position detection unit 13 a performs position detection processing based on the line-of-sight area information output from the line-of-sight area calculation unit 17. Specifically, the position detection unit 13a performs position detection processing on a cell included in the line-of-sight area indicated by the line-of-sight area information in the distribution of the received radio wave intensity acquired based on the received signal. In the radar apparatus 1a, the position detection unit 13a performs position detection processing on the cells included in the line-of-sight region, so that the erroneous detection determination unit 15 of the radar apparatus 1 is not required.

  The line-of-sight region calculation unit 17 calculates a region that is a line-of-sight region in the detection range of the radar device 1a based on the line-of-sight information stored in the storage unit 11 and the position information of the own device. The line-of-sight area calculation unit 17 outputs information representing the calculated line-of-sight area to the position detection unit 13a as line-of-sight area information. When the radar apparatus 1a is fixedly installed at a predetermined location and the line-of-sight information does not change, the line-of-sight area information calculated in advance may be stored in the storage unit 11. In this case, the radar apparatus 1a may be configured as an apparatus that does not include the line-of-sight area calculation unit 17 by the position detection unit 13a acquiring the line-of-sight area information from the storage unit 11.

FIG. 9 is a flowchart showing a flow of processing in which the radar apparatus 1a according to the second embodiment detects an object within the detection range.
In the figure, the same processes as those in FIG. 7 are denoted by the same reference numerals as those in FIG.
First, the radio wave transmission / reception unit 12 of the radar apparatus 1a receives a radio wave reflected in the direction of the own apparatus among the radio waves radiated from the own apparatus (step S101). The position detection unit 13 a acquires the line-of-sight area information output from the line-of-sight area calculation unit 17. The position detection unit 13a performs position detection processing on the cells included in the line-of-sight area indicated by the line-of-sight area information of the received signal, and detects a detection target within the detection range (step S201).

  When the detection target is not detected in the position detection process (step S103—NO), the position detection unit 13a ends the process. On the other hand, when the detection target is detected (step S103-YES), the position detection unit 13a acquires the three-dimensional position of the detection target, and outputs information indicating the acquired three-dimensional position of the detection target to the data processing unit 16. (Step S106).

FIG. 10 is a schematic diagram illustrating an outline of position detection processing in the second embodiment.
In the figure, D ₂ represents the position of the shield present on the distance axis. For example in the figure, the radar apparatus 1a performs the position detection processing for cells between the position and D ₂ of the apparatus. Therefore, the radar apparatus 1a, it is possible to reduce the calculation amount for D ₂ and subsequent cell in the location processing. Therefore, as shown in the figure, even if the erroneous detection is generated at the position of D ₁ of the received signal strength 8, a radar device 1a is possible to suppress the occurrence of erroneous detection without performing position detection process it can.

  The radar apparatus 1a according to the second embodiment configured as described above has a function of performing position detection processing on cells included in the line-of-sight region. By having this function, the radar apparatus 1a performs position detection processing on an area where the target may be detected in the detection range. Therefore, the radar apparatus 1a according to the second embodiment can reduce the calculation amount in the position detection process, and can improve the detection performance.

  According to at least one embodiment described above, the position of the detection target is detected based on the received radio wave, and the validity of the detection result is determined based on the position of the detection target and the spatial information regarding the position and height of the object. By having the function of determining the property, occurrence of erroneous detection in the radar apparatus can be suppressed.

  The occurrence of erroneous detection in the radar apparatus 1 means that the target to be detected cannot be detected or the detection of the target is delayed. Then, due to the occurrence of erroneous detection, the radar apparatus 1 may perform processing that does not need to be executed originally, and the utilization efficiency of system resources of the radar apparatus 1 may be reduced. In the radar apparatus 1 according to the embodiment, occurrence of erroneous detection is suppressed by the above function, and a decrease in utilization efficiency of system resources is suppressed.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1, 1a ... Radar apparatus, 11 ... Memory | storage part, 12 ... Radio wave transmission / reception part, 13, 13a ... Position detection part, 14 ... Out-of-sight area calculation part, 15 ... False detection determination part, 16 ... Data processing part, 17 ... Outlook Inner region calculation unit, 2-1, 2-2 ... boundary line, 3-1, 3-2 ... detection target, 4 ... reflected wave, 5 ... shielding object, 6 ... non-line-of-sight region, 7 ... shielding object position, 8 8-1: Received radio wave intensity distribution

Claims (4)

A transmission / reception unit for transmitting and receiving radio waves;
A detection unit for detecting a position of a detection target based on the radio wave received by the transmission / reception unit;
A storage unit for storing spatial information about the position and height of the object;
A determination unit that determines the validity of a detection result based on the position of the detection target and the spatial information;
A radar apparatus comprising: A calculation unit for calculating line-of-sight region information for determining the validity of the detection result based on the spatial information and the position of the device itself;
The determination unit determines the validity of a detection result based on the line-of-sight region information and the position of the detection target.
The radar apparatus according to claim 1. The calculation unit calculates, as the line-of-sight area information, information indicating a non-line-of-sight area that is outside the line-of-sight of the device within the detection range,
The determination unit determines the position of the detection target as an invalid detection result when the position of the detection target is within the non-line-of-sight region, and when the position of the detection target is outside the non-line-of-sight region, Determine the position of the detection target as a valid detection result,
The radar apparatus according to claim 2. A transmission / reception unit for transmitting and receiving radio waves;
A storage unit for storing spatial information about the position and height of the object;
Based on the spatial information and the position of the own device, a calculation unit that calculates information indicating a line-of-sight region that is within the line-of-sight of the own device in the detection range, as line-of-sight region information;
A detection unit for detecting a position of the detection target located in the line-of-sight region based on the radio wave received by the transmission / reception unit and the line-of-sight region information;
A radar apparatus comprising:

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