JP2005249743A - Radar system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radar system capable of stably demonstrating all possible functions even at the presence of effects of noise in part due to sunlight etc. <P>SOLUTION: The radar system is provided with both a noise detection means (a noise detection circuit 30 and an operation part 4) for detecting the intensity of noise inputted to a receiving part for every detection region and a region propriety setting means (the operation part 4) for executing a region invalidation setting for invalidating corresponding detection regions for detecting objects when detected noise intensity becomes equal to a specific noise threshold value or higher and executing a region validating setting for validating corresponding detection regions for detecting objects when the noise intensity becomes equal to the specific noise threshold value or lower. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a radar device that is mounted on a vehicle, for example, and measures the presence / absence of a preceding vehicle or the like and position information thereof using an electromagnetic wave such as laser light or millimeter wave, and a vehicle control system using the radar device.

  Conventionally, development of a radar apparatus for monitoring a front obstacle in a vehicle, tracking control for a preceding vehicle, and the like has been widely promoted, and a radio wave system or a laser system is known as a system. This means that electromagnetic waves such as radio waves and laser beams are transmitted in pulse form to objects (reflectors of other vehicles, etc.), and the distance to the object is obtained from the delay time until the reflected waves are received. Is detected and the direction of the object is detected. The scanning method includes a scanning method that realizes scanning by moving a transmission unit, and a scanning method that realizes scanning by moving a transmission unit and a reception unit.

  By the way, in such a vehicular radar apparatus, as described in Patent Documents 1 to 3, when noise due to disturbance light (for example, sunlight) or the like reaches a predetermined reception intensity, an object such as a preceding vehicle is obtained. Is difficult or impossible to detect. For example, in the case of a laser radar device using a photodiode as a light receiving element, if the maximum current determined by the load resistance and power supply voltage connected in series to the photodiode flows, the terminal voltage of the photodiode no longer changes. This is because a saturation phenomenon occurs in which the reflected wave signal cannot be extracted from the change in the terminal voltage.

  Therefore, conventionally, as seen in Patent Documents 1 to 3, for example, the noise intensity is monitored based on the terminal voltage of the photodiode, and when the noise intensity (noise level) exceeds a specified value, the measurement by the radar device is performed. An alarm indicating that it is impossible is output, or a measurement operation (such as a calculation for obtaining a distance to an object) is stopped.

Japanese Utility Model Publication No. 60-181684 JP-A-6-331745 Japanese Patent Laid-Open No. 9-318736

  However, in the above conventional technique, an alarm indicating that measurement is impossible is output only when the noise intensity exceeds a specified value in a part of the detection area (radar field of view), or all the detection areas The measurement operation in the area was stopped. For this reason, for example, only the noise intensity is excessive at only a part of the edge of the detection area, and all functions of the radar device are treated as impossible, and vehicle control based on the measurement result of the radar device (following the preceding vehicle) Control etc.) had to stop. Therefore, for example, whenever evening sunlight is temporarily incident on one side of a radar device of a vehicle that is running following tracking control, a warning is frequently output or the tracking control is contrary to the driver's will. Therefore, there is a problem that the function of the radar device may not be used effectively and stably.

In particular, when the scanning is performed by moving the receiving unit, a part where the noise such as sunlight is excessive depending on the scanning position and a part where the noise is not excessive (area where the measurement operation can be performed without problems) are likely to occur. There was a high possibility that the functions of the radar device could not be fully demonstrated. Even in such a scanning method, as described above, in the conventional method, only the noise intensity exceeds a specified value in a part of the area, and the entire detection area is treated as inoperable. This is because the.
Accordingly, an object of the present invention is to provide a radar device capable of stably exhibiting as much function as possible even if there is a part of the influence of noise due to sunlight or the like, and a vehicle control system using the radar device.

A radar apparatus according to the present application includes a transmission unit that irradiates a detection area while scanning an electromagnetic wave, and a reception unit that receives a reflected wave of the electromagnetic wave, and the received data of the reflected wave received by the reception unit. And a radar device that detects an object for each detection region obtained by dividing the detection area in the scanning direction,
Noise detection means for detecting the noise intensity input to the receiving unit for each detection region;
Area enable / disable setting for executing the area invalid setting for invalidating the detection area for object detection or the area valid setting for validating the detection area for object detection (for example, every radar measurement cycle). Means and
When the noise intensity detected by the noise detection unit exceeds or exceeds a specified noise threshold, the area availability setting unit performs area invalid setting for a corresponding detection area, and the noise intensity is set to a specified level. When the noise threshold value is below or below, the region valid setting is executed for the corresponding detection region.

Here, the “detection area” means a range in the scanning direction in which electromagnetic wave transmission / reception and object detection are performed, and is the same range as the range in which electromagnetic waves can be scanned (scanning range) or from the scanning range. Is also a small range.
The “detection area” is an area obtained by dividing the detection area in the scanning direction, and an object is detected with this area as a unit.
The “corresponding detection area” means a detection area scanned at the time when the noise intensity is detected.
In addition, the “noise threshold” is applied to the corresponding detection area before the reflected light becomes difficult or impossible due to the saturation state described above due to an increase in incident light such as sunlight or the like. The area invalid setting is set to a value to be executed.

  In a laser radar or the like mounted on a vehicle, as illustrated in FIG. 1C, an angle region (that is, a scanning range) that can be irradiated by scanning with laser light is reflected by receiving reflected waves. Data processing is set larger than the angle region (that is, the detection area) for measuring the distance data and the like, and within the detection range of this detection area (actually within the detection allowable area smaller than the scan range with a margin) By changing the setting position (software parameter) above, the position of the detection area in the scanning direction (ie, optical axis adjustment) can be adjusted to some extent without physically changing the mounting angle of the radar detection head. It is normal. The present invention is naturally applicable to the radar apparatus having such a configuration, and can also be applied to a configuration in which the detection area matches the scanning range (a configuration in which object detection is performed in the entire scanning range). It is. When the detection area is smaller than the scanning range, from the viewpoint of reducing power consumption, etc., a mode in which electromagnetic waves (laser light, etc.) are actually transmitted / received only within the detection area (detection even within the scanning range) A mode in which transmission or reception of electromagnetic waves is not performed outside the area), but transmission and reception of electromagnetic waves in the entire scanning range (mode in which transmission or reception of electromagnetic waves is performed even outside the detection area within the scanning range) But you can.

  According to this apparatus, the noise intensity is detected for each detection region, and it is sequentially determined for each detection region whether it is invalid or valid for object detection. For this reason, even if the influence of noise due to sunlight or the like is in a part of the detection area, the function of the radar apparatus can be stably exhibited as much as possible by utilizing the effective object detection result in the other detection areas. In addition, since a detection area that may be erroneously detected due to the influence of sunlight or the like is set as an invalid area and invalidated for object detection, an effect that erroneous detection hardly occurs can be obtained.

In a preferred aspect of the radar apparatus, the electromagnetic wave is light, the receiving unit is configured by a light receiving circuit in which a photodiode and a load resistor are connected in series to a power source, and the noise detection unit is A terminal voltage of the photodiode (a potential of one terminal with respect to the ground or a voltage between both terminals) is detected as the noise intensity.
With such an aspect, it is possible to provide a laser radar device that is less likely to stop all functions or cause erroneous detection due to sunlight or the like. Note that the terminal voltage increases or decreases according to the current flowing through the photodiode and saturates in the same manner as the current saturates, but does not become zero. By comparison, it is possible to accurately set the detection region in the saturation state as invalid.

  Next, the vehicle control system of the present application includes the radar device of the present application, and the detection area is set at least in front of the vehicle, and at least a preceding vehicle in the detection area is detected as the object and is detected. Control means for executing predetermined vehicle control based on the information of the detected object. Note that “vehicle control” may be, for example, constant inter-vehicle tracking control (ACC; Adaptive Cruise Control), collision prevention control (including those that reduce damage caused by a collision), or the like.

  In the present control system, the advantages of the radar apparatus of the present application described above can be utilized to perform vehicle control more stably and continuously than before. That is, in the conventional case, the influence of the noise due to sunlight or the like is only in a part of the detection area, and the function of the radar apparatus is totally disabled, and accordingly, the detection result of the radar apparatus is used. Vehicle control also had to be stopped. As a result, sunlight or the like is only strongly incident on a part of the detection area, and in some cases, the vehicle control may frequently stop against the intention of the vehicle driver and the surrounding situation. However, with this control system, there is a degree of freedom to continue the operation of the control system using the detection results in the detection area that is not affected by the sunlight of the radar device, and such problems can be significantly improved. .

Next, a preferred aspect of the present control system is that the control means interrupts the vehicle control when the area invalid setting is executed for any detection area and no preceding vehicle is detected in the own lane. Even if the area invalid setting is executed for any of the detection areas, if the preceding vehicle is detected in the own lane by the detection area where the area effective setting is executed, the control means The vehicle control is continued.
In this mode, when the preceding vehicle in the own lane continues to be detected, vehicle control such as constant inter-vehicle tracking control continues even if the influence of noise due to sunlight or the like is in some detection areas. Is done. On the other hand, when a preceding vehicle in the own lane is no longer detected, vehicle control such as constant inter-vehicle tracking control is stopped if a detection impossible state due to the influence of noise due to sunlight or the like occurs in some detection areas. For this reason, when the necessity and effectiveness of vehicle control based on the detection result of the radar device is high, the vehicle control is continued as much as possible even if there is an influence of noise due to sunlight, etc. When the performance is low, there is a practically excellent effect that the vehicle control can be stopped and the reliability can be ensured even if the influence of noise due to sunlight or the like is partly.

  Further, as another preferable aspect of the present control system, when the area invalid setting is executed for any detection area, the control means limits the acceleration of the vehicle, or the control means There is a mode in which control for notifying a vehicle occupant (at least a driver) that the field of view of the radar device is narrow is performed.

  With this aspect, safety can be ensured even when the effective detection area of the radar apparatus is narrow. For example, as shown in FIG. 5, when a part of the left side of the detection area (disturbance light influence range) is invalidated by sunlight or the like, and the effective detection area of the radar device is narrowed accordingly, As shown, the detection of the interrupted vehicle from the lane on the left is considerably delayed from the usual, and there is a concern that the safety is lowered than usual. However, in this aspect, when the detection area is narrow in this way, the passenger is notified that acceleration of the own vehicle is limited or the field of view is narrow, so the above-mentioned concern is improved. The

  The limitation on acceleration may be a mode in which an upper limit value of acceleration is set and acceleration is allowed only within this range, or a mode in which any acceleration is prohibited (only current speed maintenance or deceleration is allowed) may be used. The notification to the passenger is made by voice, display, vibration, or the like. The acceleration limitation and the notification to the passenger may be executed only when vehicle control such as constant inter-vehicle tracking control is being performed, or may be performed when the vehicle control is not being performed. May be. However, when vehicle control such as constant inter-vehicle tracking control is being performed, the driver relies on the function, so that the effect of limiting acceleration or notifying the passenger is particularly high.

According to the radar device of the present application, even if the influence of noise due to sunlight or the like is in a part of the detection region, the function of the radar device is stabilized as much as possible by utilizing the effective object detection result in the other detection region. Can be demonstrated.
Further, in the vehicle control system of the present application, it becomes possible to execute vehicle control more stably and continuously than in the past by taking advantage of the above-described radar device.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram for explaining a vehicle control system including a vehicular radar apparatus according to this embodiment. FIG. 1 (a) is a diagram showing the apparatus configuration, and FIG. FIG. 1C is a diagram illustrating a vehicle mounting example, and FIG. 1C is a diagram illustrating a relationship between a detection area and a scanning range. FIG. 2A shows a light receiving circuit and the like.
In FIG. 1, reference numeral 1 denotes a vehicle radar device (pulse echo type laser radar), and reference numeral 10 denotes information detected by the vehicle radar device 1 and constant inter-vehicle tracking control. Is a control unit that executes Here, the vehicular radar apparatus 1 includes a light projecting unit 2 (transmitting unit), a light receiving unit 3 (receiving unit), a calculation unit 4, and a scanning mechanism 5.

In this example, a noise detection circuit 30 and a calculation unit 4 (to be described later) in the light receiving unit 3 constitute a noise detection unit of the present invention, and the calculation unit 4 constitutes a region availability setting unit of the present invention.
The vehicle radar device 1 is mounted on the host vehicle C1 as shown in FIG. 1B, for example, and irradiates the detection area in front of the host vehicle C1 with a laser beam and exists in the detection area. The reflector of the preceding vehicle C2 is detected as an object. The detection area of the present invention is not limited to the front of the vehicle, but may be set to the rear, for example, to detect an object (such as a following vehicle) behind the host vehicle.

Here, the light projecting unit 2 includes a radar transmission head including an LD (laser diode) and an optical system attached thereto, and an LD driving circuit. The light receiving section 3 includes a PD (photodiode; shown in FIG. 2A) and a radar receiving head composed of an optical system attached thereto and a light receiving circuit 20 (FIG. 2A) that processes the output of the PD. And a noise detection circuit 30 (shown in FIG. 2 (a)) for detecting that the noise intensity due to sunlight incident on the PD exceeds a specified value.
Note that the drive circuit is a circuit that is controlled by the calculation unit 4 to operate the LD at each light emission timing created by the calculation unit 4 to output laser light (laser pulse). Here, the light emission timing is set in advance so that light emission and light reception are performed a predetermined number of times in a detection area obtained by dividing the detection area with a certain width in the scanning direction. Further, the light emission period of the laser light may be constant.

The scanning mechanism 5 can transmit the laser beam output from the LD by scanning at least a predetermined angle (that is, scanning range) in the left-right direction by a reflection mirror that is driven to swing. Controlled at a predetermined timing and cycle. For example, as shown in FIG. 1C, the scanning range is set wider than the detection area where the object is detected, and the optical axis can be adjusted by changing the soft parameter described above. In this example, a one-dimensional scanning method in which scanning is performed only in the horizontal direction (horizontal direction) will be mainly described as an example. However, for example, a two-dimensional scanning method in which scanning is performed in the vertical direction and the horizontal direction may be possible. .
The scanning speed may be a constant speed. Further, the scanning mechanism 5 in this case includes a scanning position detection sensor that detects the scanning direction and inputs the signal (scanning direction signal) to the calculation unit 4.

  The PD is used to receive the reflected light that is returned from the transmitted laser light reflected by the object. For example, the PD is incorporated in the light receiving circuit 20 shown in FIG. A corresponding electrical signal (hereinafter referred to as a received light amount signal) is output. In this case, in the light receiving circuit 20, the load resistors R1, PD and the load resistor R2 are sequentially connected between the power supply line to which a constant voltage Vb (reverse bias power supply voltage) is applied and the ground line, and the PD ground side The terminal (anode side terminal) is connected to the ground by the capacitor C1, and the capacitor C2 and the amplifier circuit 21 are sequentially connected between the power supply side terminal (cathode side terminal) and the output terminal of the PD.

  Then, both terminal voltages of the PD are output as the received light amount signal. In this example, the change (AC component) of the voltage between these terminals (that is, the reverse bias voltage of the PD) is caused by the action of the capacitors C1 and C2. It is taken out, further amplified by the amplifier circuit 21, and outputted as a voltage change of the output terminal. The voltage change at the output terminal (output of the light receiving circuit 20) is read by the arithmetic unit 4. That is, at the sampling period corresponding to the light emission timing, for example, the voltage of the output terminal is read for a certain time after light emission, and the received light amount data (hereinafter referred to as received light waveform data) with the delay time (distance) as the horizontal axis. Generated. When the received light waveform data is transmitted and received a plurality of times in the detection area described above (when there are a plurality of waveform data for one detection area), for example, the received light waveform data is integrated for each detection area. For example, the received data is stored in a memory in the calculation unit 4. For example, the received light amount at the peak position of the received light waveform data is stored as received light amount (reception intensity) data of each detection region, and the distance value calculated based on the delay time of the peak position of the received light waveform data Is stored as data of the distance to the object for each detection region.

  When the amount of incident light on the PD increases due to the influence of sunlight or the like, and the amount of current flowing through the PD increases, as shown in the circuit diagram of FIG. And the ground terminal voltage of the PD increases by the voltage drop of the resistor R2, and the terminal voltage of the PD decreases according to the amount of light. However, when the current flowing through the PD reaches the maximum current determined by the load resistors R1, R2, etc. and the power supply voltage Vb, the amount of current becomes flat even when the amount of incident light increases, and the terminal voltage of the PD is saturated. A phenomenon occurs. In this saturation state, the voltage between the terminals does not change, and even if reflected light is incident, the waveform is not output to the output terminal of the light receiving circuit 20, and the reflected light cannot be detected.

  Next, the noise detection circuit 30 will be described. As shown in FIG. 2A, the noise detection circuit 30 divides the ground terminal voltage of the PD to generate the input voltage and resistors R3 and R4, and the power supply voltage Vcc to divide the noise threshold. Resistors R5 and R6 for generating a reference voltage, and a comparator 31 that activates the output voltage (the voltage at the NL terminal) (for example, a high potential) when the input voltage exceeds or exceeds the reference voltage. Have. Then, the reference voltage (noise threshold value) is the voltage at the NL terminal before the reflected light is difficult or impossible to be detected due to the increase in incident light such as sunlight. It is set to an active value.

Next, the calculation unit 4 is a circuit including a microcomputer (hereinafter referred to as a microcomputer) including a CPU, a ROM, a RAM, and the like, and appropriately executes, for example, the processing shown in the flowchart of FIG. To perform object recognition. Hereinafter, this process will be described.
When the process is started, first, in step S1, the above-described measurement operations (transmission and reception of laser light, generation and storage of the above-described received light waveform data, etc.) are executed, and this measurement operation is executed for one detection region. Each time, the process proceeds to step S2.
Next, in step S2, it is determined whether or not the voltage (NL signal) of the NL terminal is activated during the execution of the measurement operation in step S1. If it is activated, the process proceeds to step S3. Proceed to S9.

  In step S3, the area invalidation setting is executed for the current detection area, and the process proceeds to step S4. Specifically, as the area invalid setting, for example, a process of turning on an area invalid flag provided for each detection area is executed. On the other hand, in step S9, after the area valid setting is executed for the current detection area, the process proceeds to step S4. As the area valid setting, for example, a process for turning off the area invalid flag is executed. A flag different from the area invalid setting may be provided for the area valid setting. In addition, by simply storing the latest value of the NL signal for each detection area, a configuration that realizes the area invalid setting and the area valid setting (the area where the NL signal is stored as ON is the area invalid setting, An area in which the NL signal is stored as OFF may be treated as an area valid setting).

Note that the region invalid setting and region valid setting data are transmitted to a host control device 10 that executes constant inter-vehicle tracking control and the like.
Next, in step S4, it is determined whether or not the measurement operation has been completed for all detection regions. If the determination result in step S4 is affirmative, steps S5 to S8 are sequentially executed, and if negative, the process returns to step S1 to repeat the measurement operation for the next detection region.

  In step S5, of the detection areas (hereinafter, referred to as targets in some cases) determined to be detected as having an object, the adjacent areas are grouped and collected as a set of detection areas (target set). The detection determination is performed by determining, as a target, a detection area in which the data of the amount of received light exceeds, for example, a preset detection threshold among the detection areas that are set to be effective. In addition, the target grouping may be performed by, for example, a two-dimensional coordinate system (position coordinates of the vehicle left-right direction and the vehicle front-rear direction in the scanning direction) or a three-dimensional coordinate system (vehicle front-rear direction, left-right direction, and vertical position). (Coordinates) is performed by associating targets (for example, adjacent ones) in close positions as one set. Specifically, various known methods can be employed.

Next, in step S6, an object extraction process for extracting (separating) individual objects from the target set grouped in step S5 and calculating the center position and size is executed. For example, both ends of the grouped target set are determined as the both end positions of the object, and the center thereof is determined as the center position of the object.
Next, in step S7, the data of the object extracted in step S6 in the previous sequence is compared with the data of the object extracted in step S6 in the current sequence, and a process of associating as the same object is performed. For example, a position range having a predetermined spread is set with reference to the position of the previous object, and if the position of the current object is within this position range, a process of determining the same object is executed.

Next, in step S8, monitoring target data such as a preceding vehicle is selected from the recognized object data, for example, for constant inter-vehicle tracking control. Specifically, the size of the object in the scanning direction (vehicle width in the case of one-dimensional scanning, vehicle width, height, and shape in the case of two-dimensional scanning) corresponds to the vehicle, Judgment of own lane based on road shape estimated by white line detection by camera image and yaw rate sensor / steering angle sensor / wheel speed sensor, etc. The data of the object that satisfies the selection condition such as that it is determined that the object is not a stop based on the relative speed (the difference between the previous object position and the current object position in the front-rear direction) with respect to the host vehicle Is selected. Note that the data on the preceding vehicle and the like is transmitted to a host control device 10 that executes constant inter-vehicle tracking control and the like.
When step S8 is completed, the process returns to step S1 and is repeated at the next execution timing.

  Next, the control device 10 is a device including a microcomputer. Based on the information detected by the radar device 1, the control device 10 controls the vehicle engine, the braking system, the display device, or the like as necessary to perform constant inter-vehicle tracking control or the like. It has a function to realize vehicle control. Further, in this case, the control device 10 executes the processing shown in the flowchart of FIG. 4 in association with the vehicle control (for example, the control is performed after the ignition switch of the vehicle is turned on and the microcomputer is activated). Is realized stably and effectively, and high safety is ensured. Hereinafter, this process will be described.

When the process is started, first, in step S11, it is determined whether or not the area invalid setting executed in step S3 in the process of FIG. 3 has been executed for any one or more detection areas. If even one is set, the process proceeds to step S12, and if not, the process proceeds to step S16.
In step S12, it is determined whether or not a preceding vehicle is detected in the own lane. If a part of the preceding vehicle is detected in the own lane, the process proceeds to step S13. Otherwise, the process proceeds to step S18. .

And in step S13, it transfers to acceleration restriction | limiting mode and progresses to step S14. In the acceleration limit mode, the control device 10 limits the acceleration of the vehicle. For the limitation of acceleration, for example, an upper limit value of acceleration is set, and acceleration is allowed only within this range.
Next, in step S14, control is performed to notify the driver or the like by display, voice, or the like that the area invalid setting is set and the detection area (viewing angle) is narrow by that amount.

  Next, in step S15, it is determined whether or not a switch for commanding execution of vehicle control such as constant inter-vehicle tracking control (eg, an ACC switch) is turned on. If it is turned on, the process returns to step S11 to repeat the process. If not, the vehicle control such as the constant inter-vehicle tracking control is not instructed, and the series of processes is terminated.

On the other hand, in step S16, the process proceeds to the normal mode, and the process proceeds to step S17. In the normal mode, vehicle control such as constant inter-vehicle tracking control is performed in a normal state (a state in which the above-described acceleration limitation and notification to the driver are not performed).
Next, in step S17, the notification to the driver performed in steps S14 and S19 is canceled, and the process proceeds to step S15.

In step S18, vehicle control such as constant inter-vehicle tracking control is canceled (stops against the command of the ACC switch), and the process proceeds to step S19. When a plurality of vehicle controls are performed, specific vehicle control (control such as simply monitoring and displaying an obstacle) that does not cause a problem even if the detection area is narrow may not be canceled.
Next, in step S19, control is performed to notify the driver or the like by voice or display that the vehicle control such as constant inter-vehicle tracking control is canceled because the detection area is small, and the process proceeds to step S15. .

  In the vehicle radar apparatus 1 described above, the noise intensity (PD terminal voltage) is detected for each detection region, and it is sequentially determined for each detection region whether it is invalid or valid for object detection (step S2). , S3, S9). For example, when the waveform of the received light noise with respect to the scanning position is as shown in FIG. 2B, the NL signal becomes active when the noise intensity becomes equal to or higher than the noise threshold (35 in the figure). The area invalid setting is executed for the activated area, and the data is invalidated. Note that the light reception noise in FIG. 2B is not a voltage at the PD terminal voltage (DC component) but a voltage observed at a time other than the timing at which the reflected wave may be received at the output terminal in FIG. (Noise that appears as a change in the voltage between terminals of the PD (AC component)). In FIG. 2B, the portions indicated by the symbols W1 and W2 are portions that are not saturated but the noise intensity is equal to or higher than the noise threshold value, and it is difficult to detect the reflected wave (object detection). In addition, the portion indicated by the symbol W3 in FIG. 2B is a portion where the above-described saturation state (the received light noise is almost zero) and the detection of the reflected wave (object detection) is impossible. In this example, the areas where object detection is difficult or impossible are all set as invalid areas and are not used for object detection.

  Therefore, even if the influence of noise due to sunlight or the like is in a part of the detection area, the radar device is used as much as possible by utilizing the effective object detection result in the other detection area (area where the area is effective). The function as can be stably demonstrated. In addition, since a detection area that may be erroneously detected due to the influence of sunlight or the like is set as an invalid area and invalidated for object detection, an effect that erroneous detection hardly occurs can be obtained.

  In the control system of this example, the advantages of the radar device 1 can be utilized to perform vehicle control more stably and continuously than in the past. That is, in the conventional case, the influence of the noise due to sunlight or the like is only in a part of the detection area, and the function of the radar apparatus is totally disabled, and accordingly, the detection result of the radar apparatus is used. Vehicle control also had to be stopped. As a result, sunlight or the like is only strongly incident on a part of the detection area, and in some cases, the vehicle control may frequently stop against the intention of the vehicle driver and the surrounding situation. However, with this control system, there is a degree of freedom to continue the operation of the control system using the detection results in the detection area that is not affected by the sunlight of the radar device, and such problems can be significantly improved. .

Further, in this control system, when the area invalid setting is executed for any detection area and no preceding vehicle is detected in the own lane, the control device 10 (control means) interrupts the vehicle control, Even if the area invalid setting is executed for any detection area, if a preceding vehicle is detected in the own lane by the detection area where the area effective setting is executed, the control device 10 continues the vehicle control. (Steps S11, S12, S13, S18).
For this reason, when the preceding vehicle in the own lane is continuously detected, vehicle control such as constant inter-vehicle tracking control is continued even if the influence of noise due to sunlight or the like is in some detection areas. On the other hand, when a preceding vehicle in the own lane is no longer detected, vehicle control such as constant inter-vehicle tracking control is stopped if a detection impossible state due to the influence of noise due to sunlight or the like occurs in some detection areas. For this reason, when the necessity and effectiveness of vehicle control based on the detection result of the radar device is high, the vehicle control is continued as much as possible even if there is an influence of noise due to sunlight, etc. When the performance is low, there is a practically excellent effect that the vehicle control can be stopped and the reliability can be ensured even if the influence of noise due to sunlight or the like is partly.

  Further, in this control system, when the area invalid setting is executed for any of the detection areas, the control device 10 restricts the acceleration of the vehicle and the field of view of the radar device is narrowed. To the person (steps S13 and S14). For this reason, safety can be ensured even when the effective detection area of the radar apparatus is narrow. For example, as shown in FIG. 5, when a part of the left side of the detection area (disturbance light influence range) is invalidated by sunlight or the like, and the effective detection area of the radar device is narrowed accordingly, As shown, the detection of the interrupted vehicle from the lane on the left is considerably delayed from the usual, and there is a concern that the safety is lowered than usual. However, in this example, when the detection area is narrow in this way, the acceleration of the vehicle is limited and the passenger is notified that the field of view is narrow, so the above concerns are greatly improved. Is done.

In addition, this invention is not limited to the form example demonstrated above, There can be various aspects and deformation | transformation.
For example, the present invention may be applied to a radar apparatus that scans in the horizontal direction (left-right direction) as in the above-described embodiment, but scans in the up-down direction, or scans in two directions, up-down and left-right. You may apply to the radar apparatus for vehicles. The scanning is not limited to the rotation operation, and may be, for example, a linear movement (slide) of the light emitting unit or the like. As the scanning mechanism, for example, those described in Japanese Patent Application Laid-Open Nos. 2003-121542 and 2003-177348 can be used.
In addition, a configuration in which scanning is performed only on the transmission side may be employed, but in order to perform a better distance measurement operation while maintaining the reception state equal regardless of the scanning position, scanning is also performed on the reception side. desirable. For example, it may be configured to scan the reception head in synchronization with the transmission side.

In the above embodiment, the noise detection means and the area availability setting means of the present invention are configured by the arithmetic unit 4 provided in the same unit as the radar transmission / reception head, but in another unit (for example, the control device 10). The circuit and the processing means provided in the inside may constitute each of the above means.
Further, the present invention can be applied not only to a radar apparatus using laser light but also to a radar apparatus using radio waves, for example.
Needless to say, the present invention can be applied not only to a radar device for a vehicle but also to a radar device in each field.

It is a figure explaining the structure etc. of a radar apparatus. It is a figure explaining the structure etc. of a receiving circuit and a noise detection circuit. It is a flowchart which shows the control processing of a radar apparatus. It is a flowchart which shows the control processing of a vehicle control system. It is a figure explaining the condition where the detection area is narrow.

Explanation of symbols

1 Radar device 2 Projecting unit (transmitting unit)
3 Light receiver (receiver)
4. Calculation unit (noise detection means, area availability setting means)
10 Control device (control means)
30 Noise detection circuit (noise detection means)

Claims (6)

The detection unit includes a transmission unit that irradiates the electromagnetic wave while scanning the electromagnetic wave, and a reception unit that receives the reflected wave of the electromagnetic wave, and the detection is performed based on the reception data of the reflected wave received by the reception unit. A radar device that detects an object for each detection region obtained by dividing an area in a scanning direction,
Noise detection means for detecting the noise intensity input to the receiving unit for each detection region;
An area invalidity setting for invalidating the detection area for object detection, or an area validity setting for validating the detection area for object detection;
When the noise intensity detected by the noise detection unit exceeds or exceeds a specified noise threshold, the area availability setting unit performs area invalid setting for a corresponding detection area, and the noise intensity is set to a specified level. A radar apparatus, wherein a region valid setting is executed for a corresponding detection region when the noise threshold value is below or below the noise threshold. The electromagnetic wave is light, and the receiving unit is composed of a light receiving circuit in which a photodiode and a load resistor are connected in series with a power source, and the noise detecting means converts the terminal voltage of the photodiode into the noise intensity. The radar device according to claim 1, wherein the radar device is detected as: The radar device according to claim 1 or 2, comprising at least the detection area in front of the vehicle, configured to detect at least a preceding vehicle in the detection area as the object, and information on the detected object A vehicle control system comprising control means for executing predetermined vehicle control based on the control. The control means interrupts the vehicle control when the area invalid setting is executed for any detection area and no preceding vehicle is detected in the own lane, and the area invalid setting is any The vehicle control is continued when the preceding vehicle is detected in the own lane by the detection area in which the effective area setting is executed even if the detection is performed for the detection area. The vehicle control system described. 5. The vehicle control system according to claim 3, wherein the control unit limits acceleration of the vehicle when the region invalidation setting is executed for any detection region. The control means executes control for notifying a vehicle occupant that the field of view of the radar apparatus is narrow when the area invalid setting is executed for any detection area. The vehicle control system according to any one of claims 3 to 5.

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