JP6452596B2 - Radar device and radar device detection method - Google Patents

Description

  The present invention relates to a radar apparatus and a radar apparatus detection method.

  Conventionally, as a radar device for monitoring a vehicle traveling on a road, for example, there are techniques shown in Patent Documents 1 and 2.

  In the technique disclosed in Patent Document 1, a vehicle position detection unit that detects a target vehicle position during traveling, and a detection position predicted by receiving detection position information from the vehicle position detection unit, Vehicle tracking means for tracking the vehicle of the vehicle, and vehicle event determination means for receiving the tracking information from the vehicle tracking means and the detected position information from the vehicle position detecting means to determine a vehicle event such as lane change or slipping through. It is characterized by. According to such a technique, lane departure can be predicted, and abnormally traveling vehicles such as lane changes, passing through, and reverse running can be detected.

  In the technique disclosed in Patent Document 2, a millimeter wave beam is irradiated by a millimeter wave radar and a plurality of traveling vehicles are detected by reflected wave reception. From the relationship between the irradiation angle, the time until reflection, and the Doppler shift, the millimeter wave is detected. Calculate the distance, direction angle, speed, etc. from the wave radar, find the vehicle's travel trajectory, graph the relationship between the number of traveling vehicles and the lane width direction, group them, and extract the number of lanes from the mountain of the graph, The lane width is extracted from the peaks and valleys on both sides of the graph. The width of the median strip at the boundary where the speed component direction of the travel locus switches from positive to negative is obtained. Vehicle traffic volume is measured and monitored based on the road layout thus obtained. According to such a technique, it is possible to monitor the vehicle traffic while measuring the traveling vehicle by the millimeter wave radar and automatically judging the number of lanes, the width of each lane, the median width, and the like.

JP 2004-280362 A JP 2007-257536 A

  However, in the techniques shown in Patent Documents 1 and 2, a rectangular detection target area along the monitoring target road is set, and vehicles existing in the detection target area are monitored. For this reason, when the road to be monitored is a curved road, there is a problem that the vehicle cannot be accurately detected.

  In addition, when the vehicle in the detection target region moves in a complicated manner, there is a problem that the calculation load increases.

  It is an object of the present invention to provide a radar device and a radar device detection method that can reduce the calculation load in response to the prediction of the course of a vehicle on a complicated road.

In order to solve the above-described problems, the present invention provides a radar device that transmits a signal, receives a signal reflected by a vehicle moving on a road, and detects the vehicle based on the received signal. A setting means for setting a target area and setting an intersection line for a part of the detection target area, and a plurality of partial detections of the detection target area set by the setting means along the traveling direction of the road A dividing unit that divides into target regions; and the vehicle is detected for each of the partial detection target regions obtained by the division by the dividing unit , and between the lane direction of the partial detection target region and the moving direction of the vehicle detecting the angle, the predetermined angular in said detecting means for predicting the path of the vehicle, the route of the vehicle predicted by the detection means for a predetermined time based on the angle If it is determined that the internal in crossing the intersection line, characterized in that the vehicle has, and determining means for determining that the vehicle is running the road in the opposite direction.
According to such a configuration, it is possible to reduce the calculation load in response to the course prediction of a vehicle on a complicated road.

The present invention further includes storage means for storing each of the lane directions of the partial detection target area, and the detection means is provided between the lane direction stored in the storage means and the moving direction of the vehicle. , And the course of the vehicle is predicted based on the angle.
According to such a configuration, it is possible to further simplify the arithmetic processing by storing the lane direction in advance.

Further, according to the present invention, the dividing unit sets a curve connecting both ends of the detection target region, divides the curve into a plurality of segments, approximates each of the divided curves with a line segment, and each line segment. The partial detection target area is set by giving a width to.
According to such a configuration, the partial detection target area can be easily set.

Further, the present invention, the setting means, a part of the detection subject region, and sets a mask region to exclude from detection target.
According to such a configuration, by setting a mask area for an area that does not need to be detected, the calculation processing load is reduced, and the vehicle can be detected with high accuracy even on a road having a complicated shape. be able to.

According to another aspect of the present invention, there is provided a radar apparatus detection method for transmitting a signal, receiving a signal reflected by a vehicle moving on a road, and detecting the vehicle based on the received signal. A setting step of setting an intersection line for a part of the detection target region, and the detection target region set in the setting step to a plurality of partial detection target regions along a traveling direction of the road The vehicle is detected for each of the partial detection target areas obtained by the division step and the division in the division step, and the angle between the lane direction of the partial detection target area and the moving direction of the vehicle is detected. and a detection step of predicting the course of the vehicle based on the angle, the path of the vehicle which is predicted in the detection step is given If it is determined that intersects with the intersecting lines within a predetermined angle in between, characterized in that the vehicle has a determination step of determining that the vehicle is running the road in the opposite direction.
According to such a method, it is possible to reduce the calculation load in response to the course prediction of a vehicle on a complicated road.

  According to the present invention, it is possible to provide a radar device and a radar device detection method that can reduce the calculation load in response to the prediction of the course of a vehicle on a complicated road.

It is a figure which shows the structural example of the radar apparatus which concerns on embodiment of this invention. It is a block diagram which shows the detailed structural example of the signal processing part shown in FIG. It is a figure for demonstrating operation | movement of embodiment shown in FIG. It is a figure which shows the example which approximated the road shown in FIG. 3 with the curve. It is a figure which shows the example which divided | segmented the curve shown in FIG. 4 and approximated with the line segment. It is a figure which shows the example which added the line segment which shows a road width with respect to the line segment shown in FIG. It is a figure which shows the example which connected the line segment shown in FIG. 6, and set the partial detection object area | region. It is a figure which shows the example which set the intersection line with respect to the example shown in FIG. It is a figure for demonstrating the mode of detection of a vehicle. It is a figure for demonstrating the mode of detection of a vehicle. It is a figure for demonstrating a mode that the course of a vehicle is estimated. It is a flowchart which shows an example of the setting and division | segmentation step process performed in embodiment shown in FIG. It is a flowchart which shows an example of the detection step process performed in embodiment shown in FIG. It is a figure for demonstrating operation | movement of a prior art. It is a figure for demonstrating the operation | movement of this embodiment. It is a figure for demonstrating a mask area | region. It is another figure for demonstrating a mask area | region.

  Next, an embodiment of the present invention will be described.

(A) Description of Configuration of Embodiment FIG. 1 is a diagram illustrating a radar apparatus according to an embodiment of the present invention. As shown in this figure, the radar apparatus 1 includes a local oscillation unit 10, a transmission unit 11, a signal processing unit 14, a reception unit 15, and an A / D (Analog to Digital) conversion unit 20 as main components. .

  Here, the local oscillation unit 10 generates a CW (Continuous Wave) signal having a predetermined frequency and supplies the CW (Continuous Wave) signal to the transmission unit 11 and the reception unit 15.

  The transmission unit 11 includes a modulation unit 12 and a transmission antenna 13. The CW signal supplied from the local oscillation unit 10 is pulse-modulated by the modulation unit 12 and transmitted to the target via the transmission antenna 13.

  The modulation unit 12 of the transmission unit 11 is controlled by the signal processing unit 14 and pulse-modulates the CW signal supplied from the local oscillation unit 10 and outputs it. The transmission antenna 13 transmits the pulse signal supplied from the modulation unit 12 toward the target.

  The signal processing unit 14 controls the modulation unit 12, the variable gain amplification unit 18, and the antenna switching unit 17, and performs arithmetic processing on the reception data supplied from the A / D conversion unit 20. Detect the target.

  FIG. 2 is a block diagram illustrating a detailed configuration example of the signal processing unit 14 illustrated in FIG. 1. As shown in FIG. 2, the signal processing unit 14 includes a storage unit 14a, a setting unit 14b, a detection unit 14c, and a control unit 14d. Here, the memory | storage part 14a is comprised by semiconductor memory etc., for example, and memorize | stores the information regarding the lane direction mentioned later. The setting unit 14b sets a detection target area and a partial detection target area described later. The detection unit 14c detects a vehicle that is a target, and executes a process of determining whether or not the detected target is traveling backward. The control unit 14d controls the storage unit 14a, the setting unit 14b, and the detection unit 14c, and controls the modulation unit 12, the variable gain amplification unit 18, and the antenna switching unit 17.

  The reception unit 15 includes a reception antenna 16, an antenna switching unit 17, a variable gain amplification unit 18, and a demodulation unit 19. The reception unit 15 receives a signal transmitted from the transmission antenna 13 and reflected by the target, and performs demodulation processing. After that, the data is output to the A / D converter 20.

  The reception antenna 16 of the reception unit 15 includes a plurality of antennas, receives a signal transmitted from the transmission antenna 13 and reflected by the target, and supplies the signal to the antenna switching unit 17. The antenna switching unit 17 is controlled by the control unit 14 d of the signal processing unit 14, selects any one of the reception antennas 16, and supplies the received signal to the variable gain amplification unit 18. The gain variable amplification unit 18 is controlled in gain by the control unit 14 d of the signal processing unit 14, amplifies the received signal supplied from the antenna switching unit 17 with a predetermined gain, and outputs the amplified signal to the demodulation unit 19. The demodulator 19 demodulates the received signal supplied from the variable gain amplifier 18 using the CW signal supplied from the local oscillator 10 and outputs the demodulated signal.

  The A / D converter 20 samples the received signal supplied from the demodulator 19 at a predetermined period, converts it into a digital signal, and supplies the digital signal to the signal processor 14.

(B) Description of Operation of Embodiment Next, the operation of the embodiment of the present invention will be described. In the embodiment of the present invention, the radar apparatus 1 has a fan-shaped detection area F as shown in FIG. 15 described later, and is fixedly installed at a position where a road to be observed falls within this detection area. Is done. When the installation of the radar apparatus 1 is completed, the following initial settings are executed.

  FIG. 3 is a diagram for explaining a process of setting a detection target region by the radar device 1 after the radar device is installed. In FIG. 3, a curved line indicated by a continuous thick line curved from the upper right to the lower left indicates a road to be detected. For such a road, the radar apparatus 1 of the present embodiment sets a detection target region as described below.

  That is, when setting the detection target area, the radar apparatus 1 receives designation of the end points P1 and P2 of the detection target area from the setter as shown in FIG. 4, and designates the centers of curvature C1 and C2 of the road. receive. Upon receiving designation of the end points P1 and P2 of the detection target area and the centers of curvature C1 and C2 of the road, the setting unit 14b of the signal processing unit 14 sets the centers of curvature C1 and C2 of the road as shown in FIG. A curve connecting the center and the end points P1 and P2 as the starting point is set by, for example, a Bezier curve, an arc, a parabolic curve, a clothoid curve, or the like. In addition, the length of the road approximated by a curve can be about 50 m, for example.

  Next, the setting unit 14b divides the curve shown in FIG. 4 into a plurality of pieces, and approximates the curve with line segments (straight lines). In the example of FIG. 5, the curve is approximated by four line segments S1 to S14. As an approximation method, for example, a curve can be approximated by a line segment by dividing the curve into a plurality of portions and setting straight lines connecting both ends of each of the divided curves. As a division | segmentation number, it can be set as about 10-15, for example. Of course, it may be divided into other numbers.

  Next, the setting unit 14b has a predetermined length orthogonal to each of the line segments S1 to S14 as illustrated in FIG. 6 with respect to the road approximated by the line segments S1 to S14 illustrated in FIG. Line segments L1 to L15 are set. In this example, line segments L1 to L15 having the same length orthogonal to the line segments S1 to S14 are set. The lengths of the line segments L1 to L15 are set to a length corresponding to the width of the target road.

  Next, as shown in FIG. 7, the setting unit 14b sets line segments A1 to A14 and B1 to B14 that connect the ends of the line segments L1 to L15. As a result, as shown in FIG. 7, partial detection target regions D1 to D14 that are regions surrounded by the line segments A1 to A14, the line segments B1 to B14, and the line segments L1 to L15 are obtained. The line segments S1 to S14, the line segments A1 to A14, and the line segments B1 to B14 are not parallel, but can be regarded as parallel if the number of divisions is sufficient with respect to the curvature. The direction of ~ S14 is defined as the lane direction.

  Next, as shown in FIG. 8, the setting unit 14b sets an intersection line CL for detecting that the vehicle is traveling backward. More specifically, in the example shown in FIG. 8, an intersection line CL is set as shown in FIG. 8 in the partial detection target region D14 that is the terminal when the vehicle runs backward. Note that the length, angle, and position of the intersection line CL can be freely set according to the use environment or the like.

  Next, the setting unit 14b stores the direction of the line segments S1 to S14 in the storage unit 14a as the lane direction for each of the partial detection target regions D1 to D14 set as described above. For example, the signal processing unit 14 stores the angles of the line segments S1 to S14 with respect to the X axis or the Y axis in the storage unit 14a.

  With the above processing, it is possible to set a detection target area for a target road and to set a plurality of partial detection target areas obtained by dividing the detection target area.

  Next, after the setting of the detection target region and the partial detection target region is completed as described above, for example, when the installation start is instructed by operating the operation unit (not shown), the following description will be given. The operation of detecting the vehicle traveling on the road is started.

  That is, the control unit 14 d of the signal processing unit 14 controls the modulation unit 12 and transmits a pulse wave via the transmission antenna 13. The pulse wave transmitted from the transmission antenna 13 is reflected by a target such as a vehicle existing in the detection region and received by the reception antenna 16. The reflected wave received by the reception antenna 16 is amplified by the variable gain amplification unit 18 via the antenna switching unit 17, demodulated by the demodulation unit 19, and supplied to the A / D conversion unit 20. The A / D converter 20 converts the analog signal supplied from the demodulator 19 into a digital signal and supplies the digital signal to the signal processor 14.

  In the signal processing unit 14, the target vehicle is detected by the detection unit 14c. For example, in the example of FIG. 9, the vehicle V existing in the partial detection target area D5 is detected by the detection unit 14c. More specifically, the detection unit 14c specifies information for identifying the position of the detected vehicle V, the moving direction of the vehicle V, the speed, and the partial detection target region where the target vehicle V is present (D5 in this example). ) Is detected.

  The detection unit 14c acquires the lane direction of the partial detection target area where the detected target exists from the storage unit 14a. In the example of FIG. 9, the lane direction of the partial detection target area D5 is acquired from the storage unit 14a. The detection unit 14c compares the moving direction of the target with the lane direction, and determines the course of the target based on the comparison result. For example, in the example of FIG. 9, from the angle between the direction of the line segment S5 that is the lane direction of the partial detection target region D5 where the vehicle V exists (the direction indicated by the broken line T in the figure) and the moving direction D of the vehicle V. The course of the vehicle V is determined. More specifically, in the example of FIG. 9, since the traveling direction of the vehicle V and the line segment S5 are substantially parallel, it is determined that the vehicle V is traveling on the road in the lane direction.

Next, the detection unit 14c predicts the course of the vehicle V from the determination result in the partial detection target region D5, the required time t until the vehicle V intersects the intersection line CL, and the intersection angle θ when intersecting. Predict. More specifically, as shown in FIG. 11, a route C of the vehicle V is predicted, and a required time t until the route C intersects the intersection line CL and an intersection angle θ at the time of intersection are predicted. The required time t can be obtained by dividing the distance from the current position of the vehicle to the intersection line CL by the speed of the vehicle V. Moreover, the intersection angle θ at the time of intersection can be estimated from, for example, a deviation from the lane direction in each partial detection target region. The required time t thus obtained is equal to or less than a predetermined threshold value t _TH (for example, 10 seconds), and the intersection angle θ when intersecting the intersection line CL is equal to the predetermined threshold value θ _TH (for example, π / 4), if | θ−π / 2 | ≦ θ _TH is satisfied, it is determined that the vehicle V is traveling in the reverse direction on the road, and an alarm is issued via an alarm unit (not shown). Issue.

  According to the above processing, since the detection target area is divided into a plurality of partial detection target areas and the vehicle is detected, the vehicle can be detected even on a curved road. Also, since the course of the vehicle is predicted from the angle between the moving direction of the vehicle and the stored lane direction in each partial detection target area, it is not necessary to calculate the lane direction each time. Can be reduced.

  Next, details of processing executed in the embodiment of the present invention will be described with reference to FIGS. 12 and 13. FIG. 12 shows processing executed when initial setting is performed when the radar apparatus 1 of the present embodiment is installed. When this flowchart is started, the following steps are executed.

  In step S10, the setting unit 14b sets the end points P1 and P2 of the detection target area of the road to be monitored. More specifically, for example, end points P1 and P2 as shown in FIG. 4 are set.

  In step S11, the setting unit 14b sets a curve connecting the end points P1 and P2. For example, in the example of FIG. 4, a curve connecting the curvature centers C1 and C2 and the end points P1 and P2 as the starting points is drawn by, for example, a Bezier curve, an arc, a parabolic curve, or a clothoid curve. To do.

  In step S12, the setting unit 14b divides the curve drawn in step S11 into a plurality. For example, in the example of FIG. 5, the curve is equally divided into 14 parts.

  In step S13, the setting unit 14b approximates the curve divided in step S12 with line segments. For example, in the example of FIG. 5, the curve is approximated by line segments S1 to S14.

  In step S14, the setting unit 14b sets a line segment that is orthogonal to each line segment. For example, in the example of FIG. 5, line segments L1 to L15 (see FIG. 6) that are orthogonal to the line segments S1 to S14 are set.

  In step S15, the setting unit 14b sets the partial detection target region by connecting the end points of the orthogonal line segments set in step S14. For example, in the example of FIG. 6, line segments A1 to A14 and line segments B1 to B14 (see FIG. 7) connecting the end points of the line segments L1 to L15 are set. Thereby, the partial detection target areas D1 to D14 divided by the line segments A1 to A14, the line segments B1 to B14, and the line segments L1 to L15 are set.

  In step S16, the setting unit 14b specifies the direction of each line segment set in step S13. For example, in the example of FIG. 5, each direction (for example, angle with respect to X-axis) of line segment S1-S14 is specified.

  In step S17, the setting unit 14b stores the direction (lane direction) of the line segment specified in step S16 together with the four vertex coordinates of the partial detection target area. For example, in the example of FIG. 5, the vertex coordinates (x, y) of the partial detection target areas D1 to D14 and the directions of the line segments S1 to S14 (for example, angles with respect to the X axis) are stored as lane directions. 14a.

  In step S18, the setting unit 14b sets an intersection line. For example, in the example of FIG. 7, the intersection line CL is set as shown in FIG. 8 in the partial detection target region D14 that is the terminal portion of the vehicle V in the reverse traveling direction.

  According to the above processing, it is possible to perform initial setting when the radar apparatus is installed.

  Next, a process executed when the radar apparatus detects the vehicle V will be described with reference to FIG. When the flowchart shown in FIG. 13 is started, the following steps are executed.

  In step S30, the control unit 14d controls the modulation unit 12 to transmit a pulse signal from the transmission antenna 13. As a result, the signal output from the local oscillation unit 10 is modulated into a pulse signal by the modulation unit 12 and transmitted to the target via the transmission antenna 13.

  In step S31, the receiving unit 15 receives the reflected wave reflected by the target. More specifically, the reflected wave reflected by the target is received by the receiving antenna 16 and supplied to the variable gain amplifying unit 18 via the antenna switching unit 17. The variable gain amplifying unit 18 amplifies the signal with a gain corresponding to the signal level and then supplies the amplified signal to the demodulating unit 19.

  In step S32, the receiving unit 15 demodulates the reflected wave, and the A / D conversion unit 20 converts the demodulated signal into a digital signal. More specifically, the demodulator 19 demodulates the signal supplied from the variable gain amplifier 18 based on the signal supplied from the local oscillator 10 and supplies the demodulated signal to the A / D converter 20. The A / D converter 20 converts the analog signal supplied from the demodulator 19 into a digital signal and outputs it.

  In step S33, the detection unit 14c detects the target from the signal acquired in step S32, and detects the detailed position, moving direction, and speed of the detected target. For example, in the example of FIG. 9, the position, moving direction D, and speed of the target vehicle V are detected.

  In step S34, the detection unit 14c reads the partial detection target area from the storage unit 14a and identifies a predetermined partial detection target area. For example, the detection unit 14c specifies the partial detection target region D5 illustrated in FIG.

  In step S35, the detection unit 14c determines whether the target is inside or outside the partial detection target area specified in step S34. For example, in the present example, the detection unit 14c determines whether the target is inside or outside in the partial detection target region D5.

  In step S36, the detection unit 14c determines whether or not the target exists in the partial detection target area specified in step S34 by the detection process in step S35, and determines that the target exists (step S36: Y). ) Proceeds to step S37, and otherwise (step S36: N) proceeds to step S43. For example, in the example of FIG. 9, since the target vehicle V exists in the partial detection target area D5, it is determined as Y and the process proceeds to step S37.

  In step S37, the detection unit 14c reads the lane direction from the storage unit 14a. More specifically, the corresponding lane direction is read out from the lane directions stored in the storage unit 14a in step S17 of FIG.

  In step S38, the detection unit 14c specifies an angle between the lane direction read in step S37 and the moving direction D of the vehicle V detected in step S33. For example, in the example of FIG. 9, the angle between the lane direction (broken line T) of the partial detection target region D5 and the moving direction D of the vehicle V is specified.

  In step S39, the detection unit 14c predicts the course of the vehicle. For example, the course is predicted based on the angle between the moving direction D of the vehicle V and the lane direction.

  In step S40, the detection unit 14c predicts the time t required for the vehicle V to cross the intersection line CL and the intersection angle θ based on the route of the vehicle V predicted in step S39. For example, the required time t required to intersect the intersection line CL is calculated by dividing the distance of the route from the vehicle V to the intersection line CL by the speed, and the intersection angle θ between the route and the intersection line CL is obtained.

In step S41, the detection unit 14c determines whether or not the intersection angle θ obtained in step S40 satisfies | θ−π / 2 | ≦ θ _TH and the required time t is equal to or less than a predetermined threshold value t _TH. If both of these conditions are satisfied (step S41: Y), the process proceeds to step S42. Otherwise (step S41: N), the process proceeds to step S43. For example, when the intersection angle θ satisfies | θ−π / 2 | ≦ θ _TH (for example, θ _TH = π / 4) and t ≦ t _TH (for example, t _TH = 10 seconds), Y is satisfied. And the process proceeds to step S42.

  In step S42, the detection unit 14c determines that the detected vehicle V is traveling backward on the road, and issues a warning from a warning unit (not shown), for example.

  In step S43, the detection unit 14c determines whether or not the processing for all the partial detection target regions has been completed, and when it is determined that the processing for all the partial detection target regions has been completed (step S43: Y). The process proceeds to step S44, and in other cases (step S43: N), the process returns to step S33 and the same process as described above is repeated. For example, when the process of the partial detection target area D1 is completed, the process returns to step S33 to execute the process of the partial detection target area D2, and when the process of the partial detection target area D14 is completed, the process proceeds to step S44. .

  In step S44, the detection unit 14c determines whether or not to continue the process. When it is determined that the process is to be continued (step S44: Y), the process returns to step S30 and the same process as described above is repeated. In other cases (step S44: N), the process ends.

  According to the above processing, it is possible to reduce the calculation load in response to the course prediction of a vehicle on a complicated road. More specifically, as shown in FIG. 14, in the simple intersection determination of the prior art, the radar apparatus 1 has a fan-shaped detection area F, and within this detection area F, a detection target area U having a rectangular shape. Is detected, the moving direction of the vehicle V within the detection target area U is detected, and reverse traveling is detected by determining whether or not the moving direction intersects the intersection line CL. For this reason, when the intersection determination is performed on a curved road as shown in FIG. 14, it is detected that the vehicle V is traveling backward until it is detected that the intersection line CL intersects the traveling direction of the vehicle V. could not. Although it is conceivable to curve the detection target region U according to the road, in such a case, it is necessary to calculate the lane direction for each position of the vehicle V, so that the calculation load is very heavy. It was. However, in this embodiment, as shown in FIG. 15, the lane directions of the plurality of partial detection target areas D1 to D5 arranged according to the curve are obtained in advance and stored, and the lane direction and the vehicle V By comparing the moving directions, reverse running can be easily detected.

(C) Description of Modified Embodiment It goes without saying that the above embodiment is merely an example, and the present invention is not limited to the case described above. For example, in the above embodiment, as the lane direction, the angle between the line segments S1 to S14 and the X axis or the Y axis is used. For example, the positive progress of the vehicle for each of the line segments S1 to S14 It may be stored as a vector having a direction from P2 to P1, and the vector of the traveling direction of the vehicle V may be compared with the stored vectors of the line segments S1 to S14. According to such a method, when the vector of the traveling direction of the vehicle V and the direction of the lane vector differ by approximately 180 degrees, it can be determined that the vehicle is traveling in the opposite direction. For this reason, as an example, when it is determined that the vehicle is traveling backward in a plurality of partial detection target areas, there is a high possibility that the vehicle is traveling backward, so that an alarm is issued without determining the intersection with the intersection line. You may make it emit.

  Moreover, although the above embodiment has been described by taking a road having no branching or merging as an example, for example, the present invention can be applied to a road having a complicated shape in which two lanes merge. In this case, for example, the detection target areas may be set for the two lanes before joining, and the partial detection target areas may be set by dividing each detection target area.

  Further, as shown in FIG. 16, when the upper and lower lanes are adjacent to each other and only one lane is detected, the target detected from the lane on the non-detection side is the position detection error of the radar device 1 or the like. May enter into a part of the detection target area and erroneously determine reverse running. In order to prevent such erroneous determination, a part of the detection target area may be masked with a mask area and excluded from the detection target. More specifically, in the example of FIG. 16, the left lane from the lower left to the upper right is set as the detection target, and the target from the right lane from the upper right to the lower left enters the partial detection target areas D2 to D4. Then, a mask region M (hatched region) is set for the partial detection target regions D2 to D4, and targets existing in the mask region M are excluded from detection targets, thereby preventing erroneous determination. be able to.

  Moreover, as shown in FIG. 17, when the width of the lane from the lower left to the upper right changes from a to b (a> b), the partial detection target areas D1 to D7 having a constant width in the direction orthogonal to the traveling direction are displayed. In addition to setting, a mask area M (hatched area) corresponding to the actual lane width is set, and this mask area M is excluded from the detection target, so that it can flexibly cope with changes in the lane width. it can.

  Further, in the present embodiment, as shown in FIG. 1, the antenna switching unit 17 switches the plurality of reception antennas 16, but a single reception antenna may be used and the antenna switching unit 17 may not be provided. Good.

  Further, in the example shown in FIG. 5 and the like, the detection target area is divided into 14, but may be divided into other numbers depending on the length of the lane to be detected.

  Further, in the above embodiment, the description has been given by taking an example of an automobile as a vehicle, but other than this, a motorcycle, a bicycle, or the like may be detected. That is, in the present specification, the vehicle is not limited to an automobile.

  12 and 13 are examples, and it goes without saying that the present invention is not limited to these flowchart processes.

DESCRIPTION OF SYMBOLS 1 Radar apparatus 10 Local oscillation part 11 Transmission part 12 Modulation part 13 Transmission antenna 14 Signal processing part 14a Memory | storage part (memory | storage means)
14b Setting unit (setting means, dividing means)
14c detector (determination means)
14d Control unit 15 Reception unit 16 Reception antenna 17 Antenna switching unit 18 Variable gain amplification unit 19 Demodulation unit 20 A / D conversion unit

Claims (5)

In a radar device that transmits a signal, receives a signal reflected by a vehicle moving on a road, and detects the vehicle based on the received signal,
Setting means for setting a detection target area on the road, and setting an intersection line for a part of the detection target area ;
A dividing unit configured to divide the detection target region set by the setting unit into a plurality of partial detection target regions along a traveling direction of the road;
The vehicle is detected for each of the partial detection target areas obtained by the division by the dividing means, and an angle between the lane direction of the partial detection target area and the moving direction of the vehicle is detected, and based on the angle Detecting means for predicting the course of the vehicle ,
If it is determined that the course of the vehicle predicted by the detection means intersects the intersection line within a predetermined angle within a predetermined time, it is determined that the vehicle is traveling in the reverse direction on the road. A determination means;
A radar apparatus comprising: Storage means for storing each of the lane directions of the partial detection target area,
The said detection means detects the angle between the said lane direction memorize | stored in the said memory | storage means, and the moving direction of the said vehicle, The course of the said vehicle is estimated based on the said angle The radar apparatus according to 1. The dividing unit sets a curve connecting both ends of the detection target region, divides the curve into a plurality of pieces, approximates each of the divided curves with line segments, and has a width for each line segment. The radar apparatus according to claim 1, wherein the partial detection target region is set by performing the operation. The radar apparatus according to claim 1, wherein the setting unit sets a mask area to be excluded from the detection target in a part of the detection target area. In a detection method of a radar apparatus for transmitting a signal, receiving a signal reflected by a vehicle moving on a road, and detecting the vehicle based on the received signal,
A setting step of setting a detection target area on the road and setting an intersection line for a part of the detection target area;
A division step of dividing the detection target area set in the setting step into a plurality of partial detection target areas along a traveling direction of the road;
The vehicle is detected for each of the partial detection target areas obtained by the division in the division step, and an angle between the lane direction of the partial detection target area and the moving direction of the vehicle is detected, and based on the angle Detection step for predicting the course of the vehicle,
If it is determined that the course of the vehicle predicted in the detection step intersects the intersection line within a predetermined angle within a predetermined time, it is determined that the vehicle is traveling in the reverse direction on the road. A determination step;
A method for detecting a radar apparatus, comprising:

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