JP2010216845A - Detection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detection apparatus that is used while switching the range for detecting an object by a radar between a wide angle range and a narrow angle range. <P>SOLUTION: An antenna 37-1 transmits a transmission signal by radiating a radio wave. A pair of antennas 51-2, 51-3, each being in one row, which are disposed at a first interval and receive a reflected radio wave out of the transmission signals. When antennas 51-1, 51-2 are defined as a single antenna and antennas 51-3, 51-4 are defined as a single antenna, a pair of these single antennas are disposed at a second interval wider than the first interval and receive a reflected radio wave out of the transmission signals. A receiving unit 12 generates a receiving signal from the radio wave received by the pair of antennas 51-2, 51-3 or the pair of the single antennas 51-1, 51-2 and 51-3, 51-4. A part 13 for processing a signal for a preparatory operation for a collision detects an object by sampling the receiving signal. The invention is applicable to a vehicle safety apparatus. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a detection apparatus, and more particularly to a detection apparatus that can be used by switching an object detection range by a radar to a wide-angle range or a narrow-angle range.

  2. Description of the Related Art Conventionally, a two-frequency CW (Continuous Wave) type sensor is known as a sensor for measuring the relative speed and distance between a host vehicle and another vehicle (see, for example, Patent Documents 1 and 2). That is, this two-frequency CW sensor detects the frequency (hereinafter referred to as the Doppler frequency) and phase of a Doppler signal with respect to the received carrier wave, and uses these to detect the relative speed between the vehicle and other vehicles. Measure distance.

  As a sensor for measuring an angle indicating a relative position between the own vehicle and another vehicle, a monopulse type sensor is known.

  In this way, the distance between the host vehicle and the other vehicle is measured using the two-frequency CW sensor, and the angle between the host vehicle and the other vehicle is measured by the monopulse sensor, so that there is an approaching other vehicle. It is possible to detect the position to perform.

Japanese Patent No. 3203600 JP 2004-69693 A

  By the way, in order to detect an object existing in a detection range set to a wide angle, a reception antenna having a wide angle directivity in the horizontal direction is required. However, in the case where there are walls on both sides of the detection range, the influence of reflection of the wall that is not the object to be detected is increased due to the wide horizontal directivity. Also, there is no object at a wide angle, or a wide angle is not required.For example, for a rear pre-crash safety device, the directivity of the horizontal detection range is narrow and a sensitive receiving antenna is required. Become.

  As a result, in order to construct a device using a radar apparatus that supports both a wide angle detection range and a narrow angle detection range, a plurality of receiving antennas having different detection ranges must be provided. There was a risk that the configuration would increase in size and cost.

  The present invention has been made in view of such a situation, and enables the directivity of an antenna to be switched between a high angle and a narrow angle with a simple configuration.

  A detection apparatus according to one aspect of the present invention is a detection apparatus that detects an object, configured to irradiate a predetermined range with radio waves, and transmitting means for transmitting a transmission signal by irradiating the radio waves; A first reception antenna that receives a reflected radio wave out of radio waves as a transmission signal transmitted by the transmission means; The antenna includes at least two rows of antenna pairs including the first receiving antenna, which are arranged at a second interval wider than the interval, and is reflected among the radio waves as transmission signals transmitted by the transmission means. A second receiving antenna for receiving an incoming radio wave, a receiving means for generating a received signal from the radio wave received by the first receiving antenna or the second receiving antenna, and the receiver The received signal generated by, by sampling, and a detection means for detecting an object.

  The transmission means is, for example, a transmission unit, and transmits a transmission signal by irradiating a predetermined range with radio waves.

  The first receiving antenna is, for example, an antenna pair arranged in a row at a first interval, and is an antenna that receives a reflected radio wave among radio waves as transmitted signals. Further, the second receiving antenna is, for example, an antenna pair of at least two columns including the first receiving antenna arranged at a second interval wider than the first interval and transmitted. Among the radio waves as transmitted signals, the reflected radio waves are received.

  That is, since the second receiving antenna has a wider antenna pair interval than the first receiving antenna, it is possible to receive radio waves reflected from objects in a narrower-angle detection range. In addition, since the second reception antenna includes at least two rows of antenna pairs including the first reception antenna, it is possible to ensure higher reception sensitivity than the first reception antenna. Therefore, by switching between the first receiving antenna and the second receiving antenna, the detection range that requires wide-angle directivity and the detection range that requires narrow-angle directivity can be switched. It becomes possible to receive radio waves.

  The reception means is, for example, a reception unit, which generates a reception signal based on a radio wave received by the first reception antenna or the second reception antenna and constitutes detection means. The signal is output to the operation signal processing unit or the lane change warning required signal processing unit.

  The detection means is, for example, a collision pre-operation signal processing unit or a lane change warning required signal processing unit, and can determine the speed, distance, and angle of the object based on the received signal. For this reason, the lane change warning signal processing unit is a relatively wide range with respect to the horizontal direction by a reception signal based on radio waves with wide-angle directivity and standard sensitivity, and a detection range in the vicinity. The signal processing unit for the preliminary collision operation has a relatively narrow range with respect to the horizontal direction due to the reception signal based on the narrow-angle directivity and high-sensitivity radio waves. Thus, it is possible to detect an object in the detection range up to a distant place.

  Among the antenna pairs of at least one column constituting the second receiving antenna, the antenna pairs excluding the antenna pairs of one column arranged at the first interval constituting the first receiving antenna are: , Constituting the first receiving antenna, sandwiching a pair of antennas arranged in a row at the first interval, arranged at a second interval, and constituting the second receiving antenna, at least 1 Among the antenna pairs for each column, the first receiving antenna, the antenna pairs excluding the antenna pairs for each column arranged at the first interval, and the first receiving antenna respectively. Connection switching means for switching between connection or disconnection of the antenna pairs arranged in a row at the first interval may be further included, and the second receiving antenna includes the second antenna of An antenna pair excluding one pair of antenna pairs arranged at the first interval and constituting the first receiving antenna among at least one pair of antenna pairs constituting the transmission antenna; A pair of antenna pairs arranged at the first interval constituting one receiving antenna are connected at the second interval wider than the first interval by being connected by the connection switching means. The antenna pair may include at least two rows of antenna pairs including the first receiving antenna.

  The first receiving antenna and the second receiving antenna are caused to function as the first receiving antenna when the connection switching means is in a non-connected state, and when the connection switching means is in a connected state, It can be made to function as two receiving antennas.

  The connection switching means is, for example, an RF switch, and by switching connection or non-connection of the RF switch, an antenna pair excluding the first reception antenna among the second reception antennas and the first switch It is possible to switch between the first receiving antenna and the second receiving antenna by connecting or disconnecting the antenna pair of the receiving antennas.

  The transmission means includes a first transmission antenna configured to irradiate radio waves to a first range that is a first angular range up to the vicinity of a first distance, and the first transmission antenna. A radio wave is irradiated to a range that includes a second angle range that is wider than the angle range and includes a second range that is close to the second distance that is closer than the first distance. A configured second transmission antenna; transmission antenna switching means for switching between the first transmission antenna and the second transmission antenna; connection or non-connection of the connection switching means; and the antenna switching means. Further, a switching signal generating means for generating a switching signal for synchronously instructing switching with the first transmitting antenna or the second transmitting antenna can be included.

  The first transmission antenna is an antenna configured to irradiate radio waves to a first range that is in a first angular range and up to the vicinity of the first distance. The second transmission antenna Is a second angle range that is wider than the first angle range, and includes a second range that includes a range close to the second distance that is closer than the first distance. The antenna switching unit is, for example, an RF switch, and the switching signal generation unit is, for example, an area switching unit.

  That is, by the switching means generated by the area switching unit, the RF switch that constitutes the antenna switching means and the RF switch that constitutes the connection switching means are switched synchronously, so that the first transmission antenna can achieve a relatively high angle. When a radio wave is transmitted to the detection range, the first receiving antenna receives a radio wave in a relatively wide angle detection range, and the second transmission antenna transmits a radio wave to a relatively narrow angle detection range. In this case, since the second receiving antenna receives radio waves in a detection range with a relatively narrow angle, it is possible to receive radio waves in a detection range suitable for the detection range of radio waves to be transmitted.

  The detection means includes a first sampling detection means for detecting an object by sampling the reception signal generated by the reception means for a first predetermined time, and the reception generated by the reception means. By sampling the signal for a second predetermined time longer than the first predetermined time, it is possible to include second sampling detection means for detecting the object, and the switching signal Based on the above, the reception signal generated from the radio wave received by the first reception antenna is output by switching to the first sampling detection means, and from the radio wave received by the second reception antenna It is possible to further include switching output means for switching the generated reception signal to the second sampling detection means and outputting it.

  The first sampling detection means is, for example, a lane change warning signal processing section, the second sampling detection means is a collision preliminary operation signal processing section, and the switching output means is, for example, a switching section. It is.

  That is, the switching unit synchronizes with the switching signal, and when the first transmission antenna transmits a radio wave to the relatively high angle detection range, the first reception antenna transmits the radio wave in the relatively wide angle detection range. When receiving, the received signal is output to the lane change warning signal processing unit, while when the radio wave is transmitted to the detection range of a relatively narrow angle by the second transmitting antenna, the second receiving antenna is compared. When receiving radio waves in a detection range of a narrow angle, it is possible to supply the signal to the collision preliminary operation signal processing unit.

  For this reason, the lane change warning signal processing unit is a relatively wide range with respect to the horizontal direction by a reception signal based on radio waves with wide-angle directivity and standard sensitivity, and a detection range in the vicinity. The signal processing unit for the preliminary collision operation has a relatively narrow range with respect to the horizontal direction due to the reception signal based on the narrow-angle directivity and high-sensitivity radio waves. Thus, it is possible to detect an object in the detection range up to a distant place.

  In one aspect of the present invention, a transmission signal is transmitted by irradiating the radio wave with an antenna configured to irradiate a predetermined range with radio waves, and the antennas are arranged in a row at a first interval. Of the radio waves as transmitted signals transmitted by the pair of first receiving antennas, the reflected radio waves are received and arranged at a second interval wider than the first interval. Among the radio waves as the transmitted signals, the reflected radio waves are received by the second reception antenna including at least two rows of antenna pairs each including the reception antenna, and the first reception antenna, or A reception signal is generated from the radio wave received by the second reception antenna, and an object is detected by sampling the generated reception signal.

  As described above, the directivity of the antenna can be switched between a high angle and a narrow angle with a simple configuration.

  According to the present invention, with a simple configuration, a wide-angle detection range with respect to the horizontal direction by the radar,

It is a figure which shows the structure of one Embodiment of the radar apparatus to which this invention is applied. It is intensity distribution of the electromagnetic wave irradiated by the transmission part of FIG. It is a figure explaining the structural example of an antenna. It is a flowchart explaining a narrow angle wide angle switching process. It is a flowchart explaining a measurement process. It is a figure explaining a measurement process. It is a figure explaining operation | movement of a distribution part. It is a figure explaining the path | route difference of the antenna in a receiving part. It is a flowchart explaining the signal processing for collision preliminary action. It is a flowchart explaining the signal processing for lane change warning. It is a figure explaining the signal processing for lane change warning. And FIG. 11 is a diagram illustrating a configuration example of a general-purpose personal computer. Alternatively, it is possible to use by switching a narrow-angle detection range.

  FIG. 1 is a diagram showing a configuration of an embodiment of a radar apparatus according to the present invention.

  The radar device 1 is mounted on a vehicle, detects a vehicle that approaches a rear range of the vehicle (a range that is substantially right behind and includes a relatively far part) at a high speed that is higher than a predetermined speed, and detects a collision. The so-called pre-crash function, which performs a preliminary operation in preparation for a collision in anticipation, and the rear side area of the vehicle (relatively close to the rear in the driving lane adjacent to the left and right when viewed from the driving lane while driving) The vehicle includes a so-called lane change support function (lane change warning function) that detects a traveling vehicle and issues a warning when there is a danger at the time of lane change.

  The radar apparatus 1 includes a transmission unit 11, a reception unit 12, a collision preliminary operation signal processing unit 13, a collision preliminary operation control unit 14, a lane change warning signal processing unit 15, and a lane change warning operation control unit 16. ing.

  The transmission unit 11 generates and radiates a radio wave composed of two frequencies CW (Continuous Wave) as a transmission signal. The reception unit 12 receives a radio wave reflected by an object among radio waves that are transmission signals transmitted from the transmission unit 11, generates a reception signal from the received radio wave, and performs a preliminary collision operation signal processing unit 13. And the lane change warning signal processor 15.

  The collision pre-operation signal processing unit 13 samples the reception signal supplied from the reception unit 12 with a relatively short period, detects the approach of another vehicle from the rear, determines the presence or absence of a collision, and determines the result. In response to this, the collision preliminary movement control unit 14 is caused to execute the collision preliminary movement. The collision preliminary operation control unit 14 controls the operation of a collision protection device that protects an occupant at the time of a collision, such as an audio warning device, a seat belt, an airbag, or a movable headrest, for example. When instructed to carry out more collision preparatory actions, a warning is given in advance by voice to call attention, and the seat belt is lifted to fix the occupant to the seat, preventing the occurrence of so-called whiplash. Or by operating the airbag at an appropriate timing before the collision to absorb the impact of the occupant at the time of the collision, or by operating the movable headrest and pressing it against the occupant's head, etc. The operation of suppressing the impact due to the reaction to the head at the time is executed.

  The lane change warning signal processing unit 15 samples the received signal supplied from the receiving unit 12 with a relatively long period, recognizes the position of the other vehicle from the rear of the side, and determines whether there is a danger when changing the lane. The lane change warning operation control unit 16 is caused to execute a lane change warning operation according to the determination result. When the lane change warning operation control unit 16 receives an instruction to prompt a warning from the lane change warning signal processing unit 15, for example, the occupant is seated so as to prompt a warning sound, a voice instruction for warning, or a warning. It warns that it is dangerous to change lanes by vibrating the seat.

  Next, a detailed configuration of the transmission unit 11 will be described.

  The transmission unit 11 includes an oscillation unit 31, a frequency switching unit 32, an amplification unit 33, a three-branch unit 34, an amplification unit 35, an RF switch 36, antennas 37-1, 37-2, and an area switching unit 38. .

  Based on the switching signal supplied from the frequency switching unit 32 at a predetermined interval, the oscillating unit 31 uses a CW signal having a frequency f1 of several tens of GHz band and a CW signal having a frequency f2 different from the frequency f1 by several MHz as a carrier wave. It is generated by switching, amplified by the amplifying unit 33 and supplied to the three branching unit 34. The frequency switching unit 32 supplies a switching signal that instructs the oscillation unit 31 to switch the frequency to be oscillated and also supplies the switching signal to the reception unit 12.

  The 3-branch unit 34 branches and supplies the CW signal having the frequency f1 or f2 supplied from the amplification unit 33 to each of the reception unit 12 and the amplification unit 35. The amplification unit 35 outputs the CW signal having the frequency f1 or f2 supplied from the three-branch unit 34 as a transmission signal as a radio wave from the antenna 37-1 or 37-2 via the RF switch 36.

  The RF switch 36 switches to either the antenna 37-1 or the antenna 37-2 based on the narrow angle switching signal or the wide angle switching signal supplied from the area switching unit 38 and is supplied from the three branch unit 34. The CW signal having the frequency f1 or f2 is output as a radio wave as a transmission signal.

  The antennas 37-1 and 37-2 are provided in the vicinity of the rear center portion of the vehicle main body, and output radio waves having intensity distribution characteristics having ranges Z1 and Z2 as shown in FIG. 2 as transmission signals, respectively. In FIG. 2, the downward direction in the figure is the traveling direction of the vehicle C1, and the antenna A (antennas 37-1, 37-2, 51-1 to 51- in FIG. 1) provided near the rear center of the vehicle C1. 4 shows the intensity distribution characteristic when radio waves are emitted.

  A range Z1 indicating the intensity distribution characteristic of the antenna 37-1 in FIG. 2 includes a position from the position where the antenna A exists to the center at the rear front, an angle α in the horizontal direction, and a position that is relatively far away. It is the range of the shaded area. Further, the range Z2 indicating the intensity distribution characteristic of the antenna 37-2 includes a position from the position where the antenna A exists to the position in the horizontal direction with an angle β (> α) in the horizontal direction and a relatively close position. This is a plain area in the figure. FIG. 2 shows a state in which the vehicle C1 is traveling in the downward direction in the figure in the lane L2 of the lanes L1 to L3. Further, in the ranges Z1 and Z2, there are overlapping ranges as shown in FIG.

  The area switching unit 38 generates a narrow angle switching signal or a wide angle switching signal at a predetermined time interval, and the RF switch 36, the RF switches 52-1 and 52-2 of the receiving unit 12, and the switching units 63-1 to 63-1. 63-3.

  Next, the configuration of the receiving unit 12 will be described.

  The receiving unit 12 includes antennas 51-1 to 51-4, RF switches 52-1 and 52-2, an adding unit 53, a subtracting unit 54, LNA (Low Noise Amplifier) 55-1 and 55-2, and a mixer 56-. 1, 56-2, distribution units 57 and 58, LPF (Low Pass Filter) 59-1 to 59-3, amplification units 60-1 to 60-3, ADC (Analog Digital Converter) 61-1 to 61-3 And switching units 62-1 to 62-3.

  The antennas 51-1 to 51-4 sequentially transmit radio waves reflected on an object such as a vehicle or a human among radio waves as transmission signals emitted from the antennas 37-1 and 37-2 of the transmission unit 11. The signal corresponding to the received radio wave is supplied to the adding unit 53 and the subtracting unit 54, respectively. As described above, the transmission signal is transmitted by sequentially switching the frequencies f1 and f2. However, when the object is moving, the Doppler frequencies fd1 and fd2 correspond to the frequencies f1 and f2 due to reflection. Will occur. For this reason, the radio waves received by the antennas 51-1 to 51-4 are switched between f1 and f2 frequencies in the transmission signal, one corresponding to the CW signal having the frequency f1 + fd1 and the one corresponding to the CW signal having the frequency f2 + fd2. In synchronization with the timing, the signals are sequentially switched and received.

  More specifically, as shown in FIG. 3, the antennas 51-1 to 51-4 are each composed of four patch antennas, and are substantially upright in the vertical direction at predetermined intervals in the horizontal direction. Yes. In FIG. 3, the horizontal direction in the figure indicates the horizontal direction of the antennas 51-1 to 51-4, and the vertical direction in the figure indicates the vertical direction of the antennas 51-1 to 51-4. The antennas 51-1 and 51-2 are connected to the RF switch 52-1, and the antennas 51-3 and 51-4 are connected to the RF switch 52-2. 2, 51-3.

  Therefore, when the RF switches 52-1 and 52-2 are in the open state, as shown in the left part of FIG. 3, among the antennas 51-1 to 51-4, radio waves are transmitted by the antennas 51-2 and 51-3. The received signal is output to the adding unit 53 and the subtracting unit 54 via the RF switches 52-1, 52-2, respectively.

  When the RF switches 52-1 and 52-2 are in the connected state, as shown in the right part of FIG. 3, among the antennas 51-1 to 51-4, the signals are received by the antennas 51-1 and 51-2. The signal on which the radio wave signal superimposed and the signal on which the radio wave signal received by each of the antennas 51-3 and 51-4 is superimposed are respectively connected via the RF switches 52-1, 52-2. The data is output to the adder 53 and the subtractor 54.

  When receiving a radio wave using a receiving antenna comprising a pair of antenna pairs, in general, the smaller the distance between the antenna pairs, the easier the reception of radio waves from a wide-angle detection range, and the wider the distance between the antenna pairs. It becomes easier to receive radio waves from a narrow-angle detection range. In addition, in the case of receiving antennas constituting each of a plurality of column antenna pairs, it is known that the reception sensitivity improves as the number of columns increases.

  Therefore, when the RF switches 52-1 and 52-2 are opened, the antenna interval is the distance L <b> 1 between the antennas 51-2 and 52-3 as shown in the left part of FIG. 3. . On the other hand, when the RF switches 52-1 and 52-2 are connected, the antennas 51-1 and 51-2 can be viewed as one antenna, and similarly, the antennas 51-3 and 51-4 are It can be seen as a single antenna. Therefore, as shown in the right part of FIG. 3, the distance L2 (> L1) between the center of gravity position between the antennas 51-1 and 51-2 and the center of gravity position between the antennas 51-3 and 51-4 is Since the distance between the pair is further comprised of two antennas each, the detection range and the reception sensitivity when the RF switches 52-1 and 52-2 are opened are compared. It is possible to have a structure that can easily receive radio waves from

  The RF switches 52-1 and 52-2 are controlled to be connected and opened in synchronization with the narrow angle switching signal and the wide angle switching signal supplied from the area switching unit 38 of the transmission unit 11.

  Therefore, when the area switching unit 38 outputs a narrow-angle switching signal, the narrow-angle switching signal is also supplied to the RF switch 36 of the transmission unit 11, so that a radio wave is transmitted from the antenna 37-1 and the corresponding radio wave is transmitted. A radio wave is transmitted to a range Z1, which is an intensity distribution range, that is, a narrow-angle detection range and a relatively distant range. At this time, since the antennas 51-1 to 51-4 are connected to the RF switches 52-1 and 52-2, the antenna interval is the distance L <b> 2 by two antenna pairs, so In the relatively distant range Z1, radio waves reflected by existing objects can be easily received.

  On the other hand, when the area switching unit 38 outputs a wide-angle switching signal, the wide-angle switching signal is also supplied to the RF switch 36 of the transmission unit 11, so that a radio wave is transmitted from the antenna 37-2 and the corresponding radio wave intensity. Radio waves are transmitted to the range Z2, which is the distribution range, that is, the wide-angle detection range. At this time, since the RF switches 52-1 and 52-2 are opened in the antennas 51-1 to 51-4, the antenna interval is a distance by one antenna pair of each of the antennas 51-2 and 52-3. Since L1 (<L2), it is easy to receive a radio wave reflected by an existing object at a wide angle and in a standard distance range Z2.

  Further, the radar device 1 including the configuration of the transmission unit 11 and the reception unit 12 is configured as an integrated package and is mounted on a substantially central portion of the rear portion of the vehicle, and the antenna 51-1 in view of the size of the vehicle. Through 51-4 and the antennas 37-1, 37-2 are disposed substantially at the same position. For this reason, the antennas 51-1 to 51-4 are reflected by an object among the radio waves as transmission signals output from the antennas 37-1 and 37-2, and are returned after being reflected at substantially the same position. Receive.

  The adder 53 adds the signals supplied from the antennas 51-1 to 51-4 and adds an f1 sum signal (a frequency (f1 + fd1) including the Doppler frequency fd1 received by reflecting the CW signal of the frequency f1). ) And f2 sum signal (sum signal of frequency (f2 + fd2) including Doppler frequency fd2 received by reflection of CW signal of frequency f2) is supplied to LNA 55-1. The subtracting unit 54 subtracts the signals supplied from the antennas 51-1 to 51-4 to obtain a difference signal (of a frequency (f1 + fd1) including the Doppler frequency fd1 received by reflecting the CW signal of the frequency f1). Difference signal) and f2 difference signal (difference signal of frequency (f2 + fd2) including Doppler frequency fd2 received by reflection of CW signal of frequency f2) is supplied to LNA 55-1.

  The LNAs 55-1 and 55-2 respectively receive the f1 sum signal or the f2 sum signal and the f1 difference signal or the f2 difference signal supplied from the adder 53 and the subtractor 54, respectively, in the mixers 56-1, The signal is amplified to the same level as the level of the CW signal having the frequency f1 or f2 supplied from the three-branch unit 34 to 56-2 and supplied to the mixers 56-1 and 56-2.

  The mixers 56-1 and 56-2 are the CW signal of the frequency f1 or f2 supplied from the three branching unit 34 of the transmission unit 11, and the f1 sum signal supplied from each of the LNAs 55-1 and 55-2. And the f1 difference signal, or the f2 sum signal and the f2 difference signal are mixed and supplied to the distributing units 57 and 58, respectively. Signals in which the f1 sum signal and the f1 difference signal are mixed with the CW signal having the frequency f1 are referred to as the fd1 sum signal and the fd1 difference signal, respectively, and the f2 sum signal and the f2 difference signal are referred to as the CW signal having the frequency f2. The signals mixed with the signals are referred to as fd2 sum signal and fd2 difference signal, respectively.

  The distribution unit 57 distributes the signal supplied from the mixer 56-1 to the LPFs 59-1, 59-2 as the fd1 sum signal and the fd2 sum signal for each frequency corresponding to the switching signal, and outputs them. To do. The allocating unit 58 distributes only the fd1 difference signal to the LPF 59-3 according to the switching signal out of the fd1 difference signal and the fd2 difference signal respectively supplied from the mixer 56-2, and outputs the result.

  The LPFs 59-1 to 59-3 smooth the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal supplied from the distribution units 57 and 58, respectively, and then supply them to the amplification units 60-1 to 60-3 To do. The amplifying units 60-1 to 60-3 amplify the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal supplied from the LPFs 59-1 to 59-3, respectively, to the ADCs 60-1 to 60-3. Supply. The ADCs 60-1 to 60-3 convert the smoothed and further amplified fd1 sum signal, fd2 sum signal, and fd1 difference signal into digital signals, and respectively receive switching signals 62-1 to 62 as received signals. -3.

  Based on the narrow-angle switching signal and the wide-angle switching signal supplied from the area switching unit 38 of the transmission unit 11, the switching units 62-1 to 62-3 receive the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal. Each digital signal is supplied to the collision preliminary motion signal control unit 13 or the lane change warning signal processing unit 15 corresponding to an appropriate detection range. More specifically, when the narrow-angle switching signal is supplied, the switching units 62-1 to 62-3 use the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal as the preliminary collision operations. When the wide-angle switching signal is supplied to the signal control unit 13, the digital signals of the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal are supplied to the lane change warning signal processing unit 15.

  Next, the configuration of the collision preliminary motion signal processing unit 13 will be described.

  The collision pre-operation signal processing unit 13 includes FFT (Fast Fourier transform) 71-1 to 71-3, a collision determination FFT timing control unit 72, a Doppler frequency calculation unit 73, a distance calculation unit 74, an angle A calculation unit 75 and a collision determination unit 76 are included.

  The FFTs 71-1 to 71-3 are, based on the control signal from the collision determination FFT timing control unit 72, the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal respectively supplied as reception signals from the reception unit 12. Are sequentially sampled and subjected to FFT processing, and the FFT 71-1 supplies the result obtained from the spectrum distribution of the fd1 sum signal to the distance calculation unit 74 and the angle calculation unit 75, and the FFT 71-2 performs the spectrum result of the fd2 sum signal. Are supplied to the Doppler frequency calculation unit 73 and the distance calculation unit 74, and the FFT 71-3 supplies the result obtained from the spectrum distribution of the fd1 difference signal to the angle calculation unit 75.

  The collision determination FFT timing control unit 72 adds the built-in counter 72a every predetermined time, and instructs the FFTs 71-1 to 71-3 to execute the FFT processing when the predetermined time T1 has elapsed.

  The Doppler frequency calculation unit 73 calculates the Doppler frequency fd2 based on the spectrum result of the fd2 sum signal supplied from the FFT 71-2, calculates the velocity v1 of the detected object from the obtained Doppler frequency fd2, and calculates the distance. It supplies to the calculation part 74, the angle calculation part 75, and the collision determination part 76.

  The distance calculation unit 74 is based on the fd1 sum signal and the fd2 difference signal supplied from the FFTs 71-1 and 71-2, and the speed v1 supplied from the Doppler frequency calculation unit 73, and the fd1 sum signal and the fd2 difference signal. The distance D1 to the object is calculated from the phase difference information and supplied to the collision determination unit 76.

  The angle calculation unit 75 calculates the angle of the position where the object exists based on the intensity ratio between the fd1 sum signal and the fd1 difference signal based on the fd1 sum signal from the FFT 71-1, the fd1 difference signal from the FFT 71-3, and the velocity v1. θ1 is calculated and supplied to the collision determination unit 76.

  The collision determination unit 76 controls the speed determination unit 76a to determine whether or not the speed v1 supplied from the Doppler frequency calculation unit 73 is equal to or higher than the predetermined speed V1. When the speed v1 is higher than the predetermined speed V1, the collision determination unit 76 controls the range determination unit 76b so that the vehicle exists within a predetermined range where there is a possibility of collision based on the distance D1 and the angle θ1. To determine whether or not to do so. The collision determination unit 76 determines that there is a possibility of collision when the range determination unit 76 determines that there is a vehicle within the predetermined range, and controls the collision preliminary operation instruction unit 76c to perform the preliminary collision operation. The controller 14 is caused to perform a collision preliminary operation.

  Next, the configuration of the lane change warning signal processing unit 15 will be described.

  The lane change warning signal processing unit 15 includes an FFT 91-1 to 91-3, a lane change warning FFT timing control unit 92, a Doppler frequency calculation unit 93, a distance calculation unit 94, an angle calculation unit 95, and a lane change warning determination unit 96. It is made up of.

  The FFTs 91-1 to 91-3 are based on the control signal from the lane change warning FFT timing control unit 92, and receive the fd1 sum signal, the fd2 sum signal, and the fd1 difference respectively supplied as the reception signals from the reception unit 12. The signal is sequentially sampled and subjected to FFT processing, and the FFT 91-1 supplies the result obtained from the spectrum distribution of the fd1 sum signal to the distance calculation unit 94 and the angle calculation unit 95, and the FFT 91-2 performs the spectrum of the fd2 sum signal. The result obtained from the distribution is supplied to the Doppler frequency calculation unit 93 and the distance calculation unit 94, and the FFT 91-3 supplies the result obtained from the spectrum distribution of the fd1 difference signal to the angle calculation unit 95.

  The lane change warning FFT timing control unit 92 adds the built-in counter 92a every predetermined time, and executes the FFT process on the FFTs 91-1 to 91-3 when the predetermined time T2 (> T1) has elapsed. To instruct. Here, the predetermined time T2 is set to be longer than the predetermined time T1, and the FFT processing by the FFTs 91-1 to 91-3 has a longer sampling time than the FFT processing by the FFTs 71-1 to 71-3. Is set to

  The Doppler frequency calculation unit 93 calculates the Doppler frequency fd2 based on the fd2 sum signal supplied from the FFT 91-2, calculates the velocity v2 of the detected object from the obtained Doppler frequency fd2, and the distance calculation unit 94. The angle calculation unit 95 and the lane change warning determination unit 96 are supplied.

  The distance calculation unit 94 is based on the fd1 sum signal and fd2 sum signal supplied from the FFTs 91-1 and 91-2 and the speed v2 supplied from the Doppler frequency calculation unit 93. The distance D2 to the object is calculated from the phase difference information and supplied to the lane change warning determination unit 96.

  Based on the fd1 sum signal and the fd1 difference signal supplied from the FFTs 91-1 and 91-3 and the velocity v 2, the angle calculation unit 95 calculates the position where the object exists from the intensity ratio of the fd1 sum signal and the fd1 difference signal. Is calculated and supplied to the lane change warning determination unit 96.

  The lane change warning determination unit 96 controls the speed determination unit 96a to determine whether or not the speed v2 supplied from the Doppler frequency calculation unit 93 is equal to or higher than a predetermined speed Va or Vb (<Va). The lane change warning determination unit 96 controls the range determination unit 96b when the speed v2 is higher than the predetermined speed Va or Vb (<Va), and based on the distance D2 and the angle θ2, the speed / range table 96d. In addition, the object is within the warning range W1 or warning range W2 (a narrow range near the warning range W1) stored in advance corresponding to each of the predetermined speeds Va <v2 or Va> v2> Vb. Determine if it exists. When the range determination unit 96b determines that there is an object in the warning range W1 or W2, the lane change warning determination unit 96 considers that there is a possibility of lane change and controls the warning instruction unit 96f. The lane change warning operation control unit 16 is caused to execute a lane change warning operation.

  The lane change warning determination unit 96 includes a data storage unit 96c that stores the speed v2, the distance D2, and the angle θ2. For example, when it is determined that a vehicle is present in the warning range until just before, but the vehicle is switched to a state where the presence of the vehicle is not detected, the lane change warning determination unit 96 controls the estimation unit 96e to store the data. Based on the speed v2, the distance D2, and the angle θ2 stored in the unit 96c, the position of the vehicle in a so-called blind spot, which is a range that cannot be detected by the received signal and includes a warning range, is estimated, The range determination unit 96b is again controlled to determine whether or not the warning range exists. At this time, if it is determined that the vehicle is in the predetermined range based on the estimated position in the blind spot, the lane change warning determination unit 96 controls the blind spot timing determination unit 96g to make it a blind spot. It is determined whether or not a predetermined time has elapsed since the last detected timing estimated to have entered, that is, whether or not a predetermined time has elapsed since entering the blind spot, and if the predetermined time has not elapsed Then, the warning instruction unit 96f is controlled to execute the lane change warning operation. On the other hand, if a predetermined time or more has elapsed since entering the blind spot, the lane change warning determination unit 96 considers that the vehicle has left the warning range, and stops the lane change warning operation (does not perform the lane change warning operation).

  With reference to the flowchart of FIG. 4, the narrow angle wide angle switching process by the area switching unit 38 will be described.

  In step S1, the area switching unit 38 generates a narrow-angle switching signal, and the RF switch 36 of the transmission unit 11, the RF switches 52-1 and 52-2 of the reception unit 12, and the switching units 62-1 to 62-3. To supply.

  In step S2, the area switching unit 38 determines whether or not the switching time Tn has elapsed, and repeats the same processing until it is determined that the switching time Tn has elapsed. In step S2, when the switching time Tn has elapsed, in step S3, the area switching unit 38 generates a wide-angle switching signal, and the RF switch 36 of the transmission unit 11 and the RF switches 52-1, 52 of the reception unit 12. -2 and the switching units 62-1 to 62-3.

  In step S4, the area switching unit 38 determines whether or not the switching time Tw has elapsed, and repeats the same processing until it is determined that the switching time Tw has elapsed. If the switching time Tw has elapsed in step S4, the process returns to step S1.

  In other words, the area switching unit 38 supplies the wide-angle switching signal when the switching time Tn elapses after supplying the narrow-angle switching signal by the above processing. Then, when the switching time Tw elapses, the area switching unit 38 supplies a narrow angle switching signal and repeats the same processing. The switching times Tn and Tw may be the same time, or may be other times.

  Next, object measurement processing by the radar apparatus 1 of FIG. 1 will be described with reference to the flowchart of FIG.

  In step S11, the oscillating unit 31 oscillates either the C1 signal of the f1 frequency or the CW signal of the f2 frequency based on the switching signal from the frequency switching unit 32, and amplifies it by the amplifying unit 33 to make three branches. Output to the unit 34. At this time, the frequency switching unit 32 also supplies the same switching signal to the receiving unit 12. The three branching unit 34 branches the CW signal of the f1 frequency or the CW signal of the f2 frequency supplied from the amplifying unit 33 and supplies the branched CW signal to the receiving unit 12 and the amplifying unit 35, respectively. Then, the amplifying unit 35 supplies the RF switch 36 with either the CW signal having the f1 frequency or the CW signal having the f2 frequency supplied from the three-branch unit 34.

  In step S <b> 12, the RF switch 36 determines whether or not a narrow-angle switching signal has been supplied from the area switching unit 38. In step S12, for example, when the narrow-angle switching signal is supplied from the area switching unit 38 by the process of step S1 described with reference to the flowchart of FIG. 4, in step S13, the RF switch 36 By switching to and connecting to the antenna 37-1, which has a radio field intensity distribution far away, and outputting a radio wave from the antenna 37-1, it is transmitted as a transmission signal to a narrow-angle detection range. At this time, the radio wave as a transmission signal transmitted from the antenna 37-1 is output with an intensity distribution as indicated by a range Z <b> 1 in FIG. 2, for example. Note that the shape formed by the range Z1 in FIG. 2 does not have to be strict, and may be transmitted so as to obtain an intensity distribution that has a substantially similar shape.

  Since the transmission signal as the radio wave output by the process of step S13 is output by the intensity distribution indicated by the range Z1 in FIG. 2, if an object (vehicle) exists in the range composed of the range Z1, that object It is reflected by. That is, as described above, as shown in the upper part of FIG. 6, the transmission signal is simplified by assuming that antenna A (in FIG. 6, antennas 37-1, 37-2, 51-1 to 51-4 are integrated). The CW signals having the frequencies f1 and f2 are sequentially switched and output. For this reason, when reflected by the vehicle C1, which is an object, Doppler frequencies fd1 or fd2 are generated corresponding to the CW signals of the respective frequencies, so that as shown in the lower part of FIG. , F2 + fd2 is reflected as a CW signal, and a radio wave that is a reflected wave is received.

  Therefore, in step S14, the RF switches 52-1 and 52-2, based on the narrow angle switching signal supplied from the area switching unit 38 of the transmission unit 11, as shown in the right part of FIG. 51-1, 51-2 and antennas 51-3, 51-4 are connected to each other, and the narrow angle detection range indicated by the range Z1 in FIG. A radio wave reflected by an object existing inside is received, and a signal corresponding to the received radio wave is supplied to the adding unit 53 and the subtracting unit 54, respectively.

  That is, based on the narrow-angle switching signal, the radio wave of the transmission signal is transmitted by the antenna 37-1 of the transmission unit 11 with the intensity distribution indicated by the range Z1, and the antennas 51-1 to 51-4 of the reception unit 12 are transmitted. Is controlled so as to easily receive radio waves reflected from an object existing in the range Z1 which is a narrow angle detection range. Thereby, in addition to the radio wave intensity distribution of the radio wave transmitted as the transmission signal by the transmission unit 11 and the radio wave intensity distribution easily received by the reception unit 12, the radio wave is transmitted using two antenna pairs. In order to receive, the radio wave reflected by the object in the range Z1 can be appropriately received with high sensitivity.

  On the other hand, in step S12, when the wide-angle switching signal is supplied from the area switching unit 38 by the process of step S3 described with reference to the flowchart of FIG. 4, for example, in step S15, the RF switch 36 Then, the antenna 37-2 having a relatively close range of radio field intensity distribution is switched and connected, and the radio wave is output from the antenna 37-2, thereby transmitting it as a transmission signal to the wide-angle detection range. At this time, the radio wave as a transmission signal transmitted from the antenna 37-2 is output with an intensity distribution as indicated by a range Z2 in FIG. 2, for example. Note that the shape formed by the range Z2 in FIG. 2 does not have to be strict, and may be transmitted so as to obtain an intensity distribution that has a substantially similar shape.

  Since the transmission signal as the radio wave output by the process of step S15 is output by the intensity distribution indicated by the range Z2 in FIG. 2, if an object (vehicle) exists in the range composed of the range Z2, the object It is reflected by.

  Therefore, in step S16, the RF switches 52-1, 52-2, based on the wide-angle switching signal supplied from the area switching unit 38 of the transmission unit 11, as shown in the left part of FIG. -1 and 51-2 and the antennas 51-3 and 51-4 are disconnected, and the wide-angle detection range indicated by the range Z2 in FIG. 2 among the radio waves transmitted by the antenna 37-2 of the transmission unit 11 A radio wave reflected by an object existing inside is received, and a signal corresponding to the received radio wave is supplied to the adding unit 53 and the subtracting unit 54, respectively.

  That is, based on the wide-angle switching signal, the radio wave of the transmission signal is transmitted by the antenna 37-2 of the transmission unit 11 with the intensity distribution indicated by the range Z2, and the antennas 51-1 to 51-4 of the reception unit 12 are When the RF switches 52-1 and 52-2 are opened, only the antennas 51-2 and 51-3 receive the signal, so that the radio waves reflected from the object existing in the wide-angle detection range Z2 are received. It is controlled to be easy to do. Thereby, the radio wave intensity distribution of the radio wave transmitted as the transmission signal by the transmission unit 11 and the radio wave intensity distribution easy to be received by the reception unit 12 match, so that the radio wave reflected by the object in the range Z2 is appropriately received. It becomes possible to do.

  In step S17, the adding unit 53 adds the reception signals supplied from the antennas 51-1 to 51-4 to each other to generate an f1 sum signal or an f2 sum signal, and outputs the sum signal to the LNA 55-1. The voltage is amplified and output to the mixer 56-1.

  In step S18, the subtraction unit 54 subtracts the reception signals supplied from the antennas 51-1 to 51-4 from each other to generate an f1 difference signal or an f2 difference signal, and outputs the difference signal to the LNA 55-2. And output to the mixer 56-2.

  In step S19, the mixer 56-1 mixes the transmission signal supplied from the three-branch unit 34 of the transmission unit 11 and the sum signal, and outputs the sum signal to the distribution unit 57 as a mixed signal of the sum signal. Further, the mixer 56-2 mixes the transmission signal supplied from the three-branch unit 34 of the transmission unit 11 and the difference signal and outputs the mixed signal to the distribution unit 58 as a mixed signal of the difference signal.

  The processes in steps S12 to S19 are processed at different timings in the notation of the flowchart, but the actual processes are processed almost simultaneously and substantially in parallel. is there.

  In step S20, the allocating unit 57 uses the corresponding sum signal when the switching signal supplied from the frequency switching unit 32 of the transmitting unit 11 in the process of step S26 described later is a switching signal corresponding to the frequency f1. When a certain fd1 sum signal is supplied to the LPF 59-1, and the switching signal is a switching signal corresponding to the frequency f2, the corresponding sum signal fd2 sum signal is supplied to the LPF 59-2. Further, the allocating unit 58 fd1 difference signal which is a corresponding difference signal only when the switching signal supplied from the frequency switching unit 32 of the transmission unit 11 in the process of step S26 is a switching signal corresponding to the frequency f1. Is supplied to LPF59-3.

  That is, as shown in the upper left part of FIG. 7, when the frequency switching unit 32 outputs Hi as the switching signal at the frequency f1 and Low at the frequency f2, as shown in the middle left part of FIG. In response to the switching signal, the distribution unit 57 alternately receives the fd1 sum signal corresponding to the frequency f1 and the fd2 sum signal corresponding to the frequency f2 from the mixer 56-1. Sequentially supplied. At this time, when the switching signal is Hi corresponding to the frequency f1, the allocating unit 57 supplies the fd1 sum signal to the LPF 59-1 and the switching signal corresponds to the frequency f2, as shown in the upper right part of FIG. When Low, the fd2 sum signal is supplied to the LPF 59-2 as shown in the middle right part of FIG.

  Further, as shown in the upper left part of FIG. 7, when the frequency switching unit 32 outputs Hi as the switching signal at the frequency f1 and Low at the frequency f2, as shown in the lower left part of FIG. In response to the switching signal, the distribution unit 58 alternately receives the fd1 difference signal, which is the difference signal corresponding to the frequency f1, and the fd2 difference signal, which is the difference signal corresponding to the frequency f2, from the mixer 56-2. Sequentially supplied. At this time, the allocating unit 58 supplies the fd1 difference signal to the LPF 59-3 as shown in the lower right part of FIG. 7 only when the switching signal is Hi corresponding to the frequency f1.

  In step S21, the LPFs 59-1 to 59-3 smooth the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal sequentially supplied from the allocating units 57 and 58, respectively, and amplify the units 60-1 to 60-60. -3. The amplifying units 60-1 to 60-3 amplify the supplied fd1 sum signal, fd2 sum signal, and fd1 difference signal, respectively, and supply the amplified signals to the ADCs 60-1 to 60-3. The ADCs 60-1 to 60-3 convert the smoothed and further amplified fd1 sum signal, fd2 sum signal, and fd1 difference signal into digital signals and supply them to the switching units 62-1 to 62-3, respectively.

  In step S <b> 22, the switching units 62-1 to 62-3 determine whether or not a narrow angle switching signal is supplied from the area switching unit 38 of the transmission unit 11. In step S22, for example, when the narrow-angle switching signal is supplied from the area switching unit 38 by the process of step S1 described with reference to the flowchart of FIG. 4, in step S23, the switching units 62-1 to 62 are performed. -3 supplies the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal, which have been converted into digital signals, to the collision preliminary operation signal processing unit 13 as reception signals.

  On the other hand, in step S22, when the wide-angle switching signal is supplied from the area switching unit 38, for example, by the processing in step S3 described with reference to the flowchart of FIG. 62-3 supplies the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal, which are converted into digital signals, to the lane change warning signal processing unit 15 as reception signals.

  In step S25, the frequency switching unit 32 determines whether or not a predetermined time has elapsed since switching to the CW signal of the frequency f1 or f2 currently output, and the predetermined time has not elapsed. If it is determined, the process returns to step S12. On the other hand, when it is determined in step S25 that the predetermined time has elapsed, in step S26, the frequency switching unit 32 switches the switching signal, that is, a frequency different from the frequency output so far. And the oscillation unit 31 oscillates the CW signal.

  The above processing is summarized as follows. In the processing of step S13 or S15, for example, if the radio waves output from the antennas 37-1 and 37-2 of the transmission unit 11 are expressed by the following equation (1), the antennas 51-1 to 51- The radio wave received at 4 is expressed as the following equations (2) and (3).

  Here, Ti is a transmission radio wave, Rx1 and Rx2 are radio waves received by the antennas 51-2 and 51-3, or the antennas 51-1 and 51, respectively. -2 and antennas 51-3 and 51-4 are regarded as one antenna, respectively, A and B are the transmitted and received radio wave strengths, respectively, and d is the distance to the object. , V is the relative speed between the vehicle on which the radar device 1 is mounted and the vehicle C1 as an object that reflects radio waves as transmission signals, and fi is the frequency of the transmitted radio waves (frequency f1, i = when i = 1). 2 is the frequency f2), c is the speed of light, L is, for example, the distance between the antennas 51-2 and 51-3 shown in FIG. Antenna 51-3, 1-4 is the distance between the center of gravity position of 1-4, and θ is the position between the center of gravity of the antennas 51-2 and 51-3 shown in FIG. The angle (arrival angle) of the object C1 from the center between the center of gravity position 51-4 and the center of gravity is shown. In addition, Lsin (θ) in the third term in parentheses in the expression (3) is one antenna 51-2 or 51-3 or one antenna 51-1 or 51-2 as shown in FIG. 2 shows the path difference of the radio waves that reach both the antenna that is assumed to be the antenna and the antenna that is assumed to be the antennas 51-3 and 51-4 as one antenna. Therefore, the antennas 51-2 and 51-3 for the radio waves received from the vehicle C1 or the antennas 51-1 and 51-2 are considered as one antenna, and the antennas 51-3 and 51-4 as one antenna. Assuming that the path to the antenna is parallel to the antenna, the antennas 51-2 and 51-3 or the antennas 51-1 and 51-2 are considered as one antenna and the antenna 51-3. , 51-4 have a phase difference corresponding to the path difference Lsin (θ) in the received signal received by both antennas.

  Therefore, in the process of step S17, the adding unit 53 assumes that the antennas 51-2 and 51-3 or the antennas 51-1 and 51-2 represented by the expressions (2) and (3) are one. The sum signal Radd represented by the following equation (4) is generated by adding the signals of the radio waves received by the antennas and the antennas assuming that the antennas 51-3 and 51-4 are one antenna. . In Expression (4), information on the phase difference caused by the path difference Lsin (θ) is expressed as an amplitude. That is, in the expression (4), the information of the phase difference caused by the path difference Lsin (θ) is expressed as an amplitude by the term 2Bcos (π · Lsin (θ) · fi / c).

  Further, in the process of step S18, the subtracting unit 54 considers the antennas 51-2 and 51-3 or the antennas 51-1 and 51-2 represented by the equations (2) and (3) as one. By subtracting the signal corresponding to the received radio wave between the antenna and the antennas assuming that the antennas 51-3 and 51-4 are one antenna, a difference signal Rsub represented by the following equation (5) is generated. . In Expression (5), information on the phase difference caused by the path difference Lsin (θ) is expressed as an amplitude. That is, in the expression (5), the information of the phase difference caused by the path difference Lsin (θ) is expressed as the amplitude by the term 2Bsin (π · Lsin (θ) · fi / c).

Then, by the processing of step S19, the mixers 56-1 and 56-2 mix the sum signal Radd and the difference signal Rsub represented by the equations (4) and (5) with the transmission signals, respectively. A sum signal mixed signal Radd_d and a difference signal mixed signal Rsub_d represented by the following equations (6) and (7) are obtained.

  The mixed signal Radd_d of this sum signal is the fd1 sum signal or the fd2 sum signal corresponding to the frequency f1 or f2 in FIG. 7, and the mixed signal Rsub_d of the difference signal is the fd1 difference signal corresponding to the frequency f1 in FIG. .

  That is, by the above processing, the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal expressed by the equations (6) and (7) are synchronized with the switching signal of the frequency f1 or f2, and are shown in FIG. Are supplied to LPFs 59-1 to 59-3, respectively. Then, the LPFs 59-1 to 59-3 process the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal that are discretely supplied to obtain continuous values by the processing in step S21. Converted and supplied to the amplifying units 60-1 to 60-3. The amplifying units 60-1 to 60-3 amplify each and supply them to the ADCs 61-1 to 61-3. Further, the ADCs 61-1 to 61-3 convert the signals into digital signals and supply them to the switching units 62-1 to 62-3.

  Then, if the narrow angle switching signal has been supplied by the process of step S22, the switching units 62-1 to 62-3 can transmit the wide angle to the collision preliminary operation signal processing unit 13 by the process of step S23. If the switching signal has been supplied, the processing in step S24 causes the lane change warning signal processing unit 15 to receive three types of received signals (fd1 sum signal and fd2 that have been smoothed into a continuous digital signal). Sum signal and fd1 difference signal).

  That is, when a narrow-angle switching signal has been supplied, a radio wave serving as a transmission signal having an intensity distribution corresponding to the range Z1 in FIG. Correspondingly, the radio wave is received so as to correspond to the narrow angle detection range, a reception signal required for the collision preliminary operation signal processing is generated, and supplied to the collision preliminary operation signal processing unit 13. It becomes possible.

  In addition, when a wide-angle switching signal has been supplied, a radio wave serving as a transmission signal having an intensity distribution corresponding to the range Z2 in FIG. Correspondingly, it is possible to receive radio waves so as to correspond to the wide-angle detection range, generate reception signals required for lane change warning signal processing, and supply them to the lane change warning signal processing unit 15. .

  As a result, it is possible to receive radio waves that are transmission signals according to processing, and to appropriately receive radio waves according to the irradiation. 13 or the lane change warning signal processing unit 15 can be supplied.

  Next, with reference to the flowchart of FIG. 9, signal processing for collision preliminary operation will be described.

  In step S31, the collision determination FFT timing control unit 72 initializes the count value X of the collision determination FFT timing measurement counter 72a and starts counting.

  In step S32, the FFTs 71-1 to 71-3 acquire the fd1 sum signal and the fd2 sum signal, and the fd1 difference signal, which are digital signals supplied from the receiving unit 12, and sequentially store and sample them.

  In step S33, the collision determination FFT timing control unit 72 determines whether or not the count value X of the counter 72a exceeds a predetermined time T1, that is, whether or not a predetermined sampling time is exceeded. The time T1 is determined to be a relatively short time since it is necessary to execute a preliminary operation for responding to the collision when the collision is determined and the collision is determined. The time is shorter than the sampling time of the signal processing for lane change warning.

  If it is determined in step S33 that the count value X is not greater than the predetermined time T1, the process returns to step S32. That is, until the predetermined time T elapses, the processes of steps S32 and S33 are repeated and sampling is continued.

  In step S33, for example, when it is determined that the count value X is greater than the predetermined time T1 and it is determined that the timing for finishing the sampling and starting the processing has been reached, in step S34, the FFT timing control for collision determination The unit 72 causes the FFTs 71-1 to 71-3 to execute FFT processing. In response to this instruction, the FFTs 71-1 to 71-3 perform the FFT based on the sampled data, and the FFT 71-1 supplies the result obtained from the spectrum distribution of the fd1 sum signal to the distance calculation unit 74. To do. Further, the FFT 71-2 supplies the result obtained from the spectrum distribution of the fd2 sum signal to the Doppler frequency calculation unit 73 and the distance calculation unit 74. Further, the FFT 71-3 supplies a result obtained from the spectrum distribution of the fd1 difference signal to the angle calculation unit 75.

  In step S35, the Doppler frequency calculation unit 73 obtains the Doppler frequency fd2 based on the spectrum of the fd2 sum signal, further calculates the velocity v1 of the object from the Doppler frequency fd2, and calculates the distance calculation unit 74 and the angle calculation unit 75. And to the collision determination unit 76. That is, the relationship between the Doppler frequency fd2 and the object velocity v is expressed by the following equation (8). Here, v is the speed, fi (i = 1 or 2) is the frequency of the CW signal, and c is the speed of light. Therefore, the Doppler frequency calculation unit 73 calculates the velocity v as the velocity v1 by modifying the equation (8) based on the Doppler frequency fd2 obtained from the spectrum distribution of the fd2 sum signal.

  In step S36, the distance calculation unit 74 obtains the result obtained from the spectrum distribution of the fd1 sum signal supplied from the FFT 71-1, and the result obtained from the spectrum distribution of the fd2 sum signal supplied from the FFT 71-2. At the same time, based on the velocity v 1, the distance D 1 to the object is calculated from the phase difference between the fd 1 sum signal and the fd 2 sum signal and supplied to the collision determination unit 76.

  That is, while the frequency f1 is several tens of GHz, the frequency f2 is only a frequency difference between the frequency f1 and several MHz, so the Doppler frequencies fd1 and fd2 are represented by 2vf1 / c and 2vf2 / c, respectively. However, both can be considered to be the same.

  The phase difference Δφ between the mixed signal Radd_d of the sum signal expressed by the above-described Expressions (6) and (7) and the mixed signal Rsub_d of the difference signal is expressed by the following Expression (9). Here, if the frequency difference between the frequencies f1 and f2 is Δf, the distance d of the object is expressed by the following equation (10).

  Therefore, in step S36, the distance calculation unit 74 calculates the distance d to the object as the distance D1 using the above-described equation (10).

  In step S37, the angle calculation unit 75 calculates the fd1 sum based on the result obtained from the spectrum distribution of the fd1 sum signal supplied from the FFT 71-1, the result obtained from the spectrum distribution of the fd1 difference signal, and the velocity v1. The angle θ1 (corresponding to the arrival angle θ in FIG. 8) of the position where the object exists is calculated from the ratio between the result obtained from the signal spectral distribution and the result obtained from the spectral distribution of the fd1 difference signal. That is, the amplitudes Aadd and Asub in the mixed signal Radd_d of the sum signal and the mixed signal Rsub_d of the difference signal expressed by the above-described expressions (6) and (7) are respectively expressed by the following expressions (11) and (12). ).

  Here, the arrival angle θ in FIG. 8 is expressed as shown in the following equation (13).

  The angle calculator 75 calculates the angle θ as the angle θ1 using the above-described equation (13), and supplies the calculated angle θ1 to the collision determination unit 76.

  By the above processing, the detected object speed v1, distance D1, and angle θ1 are supplied to the collision determination unit 76 at this time.

  Therefore, in step S38, the collision determination unit 76 controls the speed determination unit 76a to determine whether or not the supplied speed v1 is higher than the predetermined speed V1. For example, when it is determined that the speed v1 is not higher than the predetermined speed V1, it is considered that there is no possibility of a collision, and the process returns to step S31.

  On the other hand, when it is determined in step S38 that the speed v1 is higher than the predetermined speed V1, in step S39, the collision determination unit 76 controls the range determination unit 76b to detect the distance of the detected object. Based on D1 and the angle θ1, the position where the object exists is obtained, and the object is present within a predetermined range where the possibility of collision is high, that is, within a predetermined distance within the range Z1 shown in FIG. To determine whether or not. In step S39, for example, when it does not exist within a predetermined range where the possibility of collision is high, it is considered that there is no possibility of collision, and the process returns to step S31. The predetermined range where the possibility of the collision is high may be set corresponding to the speed v1.

  On the other hand, when it is determined in step S39 that the collision is present within a predetermined range, the collision determination unit 76 controls the collision preliminary operation instruction unit 76c in step S40, and the collision preliminary operation control unit. 14 is instructed to perform the preliminary collision operation.

  In response to this processing, in step S41, the collision preliminary motion control unit 14 warns of the occurrence of a collision by, for example, issuing a warning sound and pulls up the seat belt to fix the occupant to the seat. To prevent the occurrence of so-called whiplash, to operate the airbag at an appropriate timing before the collision to absorb the impact of the collision, or to press the movable headrest against the head The operation of suppressing the impact due to the reaction to the head at the time of the collision of the occupant is performed.

  With the above processing, it is possible to determine the presence or absence of a collision with a relatively short sampling time, and when it is determined that there is a possibility of a collision, it is possible to perform a preliminary operation in preparation for the collision. Safety can be improved. In addition, as described above with reference to FIG. 2, the range Z1 is set as a detection range relatively far by outputting a strong radio wave as a transmission signal. If the signal is so close that it is detected, the received signal will also be received as a strong radio wave as it approaches, so even if the sampling time is short, relatively good data is sampled. Therefore, the presence or absence of a collision with the own vehicle can be detected with high accuracy.

  Next, lane change warning signal processing will be described with reference to the flowchart of FIG.

  In step S51, the lane change warning FFT timing control unit 92 initializes the count value Y of the lane change warning FFT timing measurement counter 92a and starts counting.

  In step S52, the FFTs 91-1 to 91-3 acquire the fd1 sum signal, the fd2 sum signal, and the fd1 difference signal supplied from the receiving unit 12, and sequentially store and sample them.

  In step S53, the lane change warning FFT timing control unit 92 determines whether or not the count value Y of the counter 92a exceeds a predetermined time T2, that is, whether or not a predetermined sampling time is exceeded. This time T2 is for determining whether there is a danger at the time of lane change, and when it is determined that there is a danger of lane change, it is necessary to issue a warning for the lane change. Therefore, it may be longer than the preliminary operation at the time of the collision, so that it may be longer than the time T1, which is the sampling time used for the process of determining the presence or absence of the collision. Can be a relatively long time.

  If it is determined in step S53 that the count value Y is not greater than the predetermined time T2, the process returns to step S52. That is, the processes in steps S52 and S53 are repeated until a predetermined time T2 has elapsed.

  In step S53, for example, when it is determined that the count value Y is greater than the predetermined time T2, and it is determined that the sampling has been completed and the processing start timing has been reached, in step S54, a lane change warning FFT The timing control unit 92 causes the FFTs 91-1 to 91-3 to execute FFT processing. In response to this instruction, the FFTs 91-1 to 91-3 perform the FFT based on the sampled data, and the FFT 91-1 supplies the result obtained from the spectrum distribution of the fd1 sum signal to the distance calculation unit 94. To do. Further, the FFT 91-2 supplies the result obtained from the spectrum distribution of the fd2 sum signal to the Doppler frequency calculation unit 93 and the distance calculation unit 94. Furthermore, the FFT 91-3 supplies the result obtained from the spectrum distribution of the fd1 difference signal to the angle calculation unit 95.

  In step S55, the Doppler frequency calculation unit 93 obtains the Doppler frequency fd2 based on the result obtained from the spectrum of the fd2 sum signal, further calculates the velocity v2 of the object from the Doppler frequency fd2, and calculates the distance calculation unit 94. It outputs to the angle calculation part 95 and the lane change warning determination part 96. The processes in the Doppler frequency calculation unit 93, the distance calculation unit 94, and the angle calculation unit 95 are substantially the same as the processes in the Doppler frequency calculation unit 73, the distance calculation unit 74, and the angle calculation unit 75 described above. Therefore, the description thereof will be omitted as appropriate in the following.

  In step S56, the distance calculation unit 94 obtains the result obtained from the spectrum distribution of the fd1 sum signal supplied from the FFT 91-1, and the result obtained from the spectrum distribution of the fd2 sum signal supplied from the FFT 91-2. In addition, a distance D2 to the object is calculated based on the speed v2 and supplied to the lane change warning determination unit 96.

  In step S57, the angle calculation unit 95 calculates the fd1 sum based on the result obtained from the spectrum distribution of the fd1 sum signal supplied from the FFT 91-1, the result obtained from the spectrum distribution of the fd1 difference signal, and the velocity v2. The angle θ2 (corresponding to the arrival angle θ in FIG. 8) of the position where the object exists is calculated from the ratio between the result obtained from the spectrum distribution of the signal and the result obtained from the spectrum distribution of the fd1 difference signal.

  By the above processing, the detected speed v2, distance D2, and angle θ2 of the object are supplied to the lane change warning determination unit 96 at this time.

  In step S58, the lane change warning determination unit 96 sequentially stores the detected velocity v2, distance D2, and angle θ2 of the detected object in the data storage unit 96c in association with the detected time information. Note that the speed v2, distance D2, and angle θ2 of the object stored in the data storage unit 96c need only store the latest several seconds, and the information stored in the data storage unit 96c is equal to or longer than a predetermined time. In this case, the latest data is overwritten and recorded in the recording area of the oldest data.

  In step S59, the lane change warning determination unit 96 controls the speed determination unit 96a to determine whether or not the supplied speed v2 is higher than the predetermined speed Va. For example, when it is determined that the speed v2 is higher than the predetermined speed Va, the process proceeds to step S60.

  In step S60, the lane change warning determination unit 96 controls the range determination unit 96b to read the warning range W1 corresponding to the speed v2 (> Va) from the speed versus range table 96d.

  In step S61, the lane change warning determination unit 96 controls the range determination unit 96b to obtain the position where the object exists based on the detected distance D2 and the angle θ2, and exists within the warning range W1. Determine whether or not to do. In step S61, for example, as shown in FIG. 11, when the radar apparatus 1 is mounted on the rear part of the vehicle C1 and the vehicle C13 exists within the warning range W1 indicated by the bold line, the lane change is dangerous. In step S62, the lane change warning determination unit 96 controls the warning instruction unit 96f to instruct the lane change warning operation control unit 16 to perform the lane change warning operation. Note that the warning range W1 in FIG. 11 is a position in the vicinity of the side of the driver's seat of the vehicle C1 when the vehicle C1 is traveling downward in the lane L2 in the drawing (a vehicle existing in the lane to be lane-changed visually). It is the range of the distance N1 from the rear to the position where the user can confirm. Although not shown, as a matter of course, the warning range is similarly set on the lane L3 side.

  In step S63, the lane change warning operation control unit 16 makes a warning sound, a voice instruction that prompts a warning, or vibrates the seat so as to prompt a warning in accordance with the instruction from the lane change warning determination unit 96 in step S62. To warn you that it is dangerous to change lanes.

  On the other hand, in step S59, for example, when it is determined that the speed v2 is not higher than the predetermined speed Va, in step S64, the lane change warning determination unit 96 controls the speed determination unit 96a to be supplied. It is determined whether or not the speed v2 is higher than a predetermined speed Vb (<Va). For example, when it is determined that the speed v2 is higher than the predetermined speed Vb, the process proceeds to step S65.

  In step S65, the lane change warning determination unit 96 controls the range determination unit 96b to read the warning range W2 corresponding to the speed v2 (> Vb) from the speed versus range table 96d.

  In step S66, the lane change warning determination unit 96 controls the range determination unit 96b to obtain the position where the object exists based on the detected distance D2 and the angle θ2, and exists within the warning range W2. Determine whether or not to do. In step S56, for example, as shown in FIG. 11, when the radar apparatus 1 is mounted on the rear portion of the vehicle C1 and the vehicle C12 exists within the warning range W2 indicated by the dotted line, the lane change is dangerous. In step S62, the lane change warning determination unit 96 controls the warning instruction unit 96f to instruct the lane change warning operation control unit 16 to perform the lane change warning operation. Note that the warning range W2 in FIG. 11 is a position in the vicinity of the side of the driver's seat of the vehicle C1 when the vehicle C1 is traveling downward in the lane L2 in the drawing (a vehicle existing in the lane to be lane-changed visually). Is a range of a distance N2 (<N1) from the rear to the rear. Although not shown, as a matter of course, the warning range is similarly set on the lane L3 side.

  If it is determined in step S61 that the position of the object is not within the warning range W1, if it is determined in step S64 that the speed v2 is not higher than the speed Vb, or if the position of the object is determined in step S66. When it is determined that the position is not within the warning range W2, in both cases, the processes of steps S62 and S63 are skipped, and the process proceeds to step S67.

  That is, the range determination unit 96b switches the warning range stored in advance in the speed versus range table 96d in accordance with the magnitude of the vehicle speed v2 detected as an object. For this reason, if the detected relative speed v2 of the vehicle is low, a warning range W2 consisting of a range relatively close to the vehicle C1 can be set so that a warning is issued after approaching to some extent. On the contrary, if the detected relative speed v2 of the vehicle is high, a warning range W1 including a relatively far range with respect to the vehicle C1 is set, so that a warning is issued even from a certain distance. Can be made. In this way, by setting the warning range according to the speed, it is possible to suppress the generation of unnecessary warnings and to issue an appropriate lane change warning according to the relative speed.

  In the above description, an example in which two warning ranges are set based on the threshold value for the speed v2 has been described. However, more warning ranges may be set by setting more threshold values. . Further, an example in which warning range information corresponding to a speed is stored in the speed vs. range table 96d in advance has been described. For example, the warning range may be set seamlessly by calculation according to the speed. .

  In step S67, the lane change warning determination unit 96 refers to the data storage unit 96c to determine whether or not a vehicle (object) has been detected just before a predetermined time. In step S67, for example, when there is data existing within the latest predetermined time as the time among the information on the velocity v2, the distance D2, and the angle θ2 of the object stored in the data storage unit 96c, in step S68 The lane change warning determination unit 96 controls the estimation unit 96e, and based on the information on the velocity v2, the distance D2, and the angle θ2 of the object within a predetermined time stored in the data storage unit 96c, The position is estimated by calculating the position of the object.

  In step S69, the lane change warning determination unit 96 controls the range determination unit 96b to determine whether or not an object exists within the warning range based on the position information of the object calculated by the estimation unit 96e. To determine. The process in step S69 is the same as the process in steps S59 to S61 and S64 to S66 described above, and a detailed description thereof will be omitted.

  When it is determined in step S69 that an object is present within the warning range from the estimated position, the lane change warning determination unit 96 controls the blind spot timing determination unit 96g so that the detected object enters the blind spot. It is determined whether or not a predetermined time has elapsed. The blind spot is a range in which the radar apparatus 1 cannot detect the presence of an object and includes a warning range. For example, when the vehicle C13 in FIG. 11 moves on the lane L1 while traveling at a higher speed than the vehicle C1 and further proceeds through the position of the vehicle C12, the radar device 1 eventually becomes incapable of being detected (out of the range Z2). Then, as shown by the vehicle C11, the vehicle reaches the blind spot B1 surrounded by a one-dot chain line. The blind spot timing determination unit 96g is a timing at which the detected object is assumed to have entered the blind spot from the speed v2, the distance D2, and the angle θ2 stored in association with the time information stored in the data storage unit 96c (last The time information detected in (2) is searched, and it is determined whether or not it is within a predetermined time from the timing at which it is assumed that the searched blind spot is entered.

  If it is determined in step S70 that the predetermined time has not elapsed since the detected object entered the blind spot, it is assumed that the detected object exists at the estimated position in the blind spot, and the lane change is performed in step S71. The warning determination unit 96 controls the warning instruction unit 96f to instruct the lane change warning operation control unit 16 to perform the lane change warning operation.

  In step S72, the lane change warning operation control unit 16 makes a warning sound, a voice instruction that prompts a warning, or vibrates the seat so as to prompt a warning in accordance with the instruction from the lane change warning determination unit 96 in step S71. To warn you that it is dangerous to change lanes.

  On the other hand, when it is determined in step S69 that there is no object within the warning range from the estimated position, the processing of steps S70 to S72 is skipped, and the processing returns to step S51.

  If it is determined in step S70 that a predetermined time has elapsed since entering the blind spot, the object that has been detected until just moved away from the blind spot and does not exist within the warning range. Assuming that the processing of steps S71 and S72 is skipped, the processing returns to step S51.

  Note that the elapsed time after the detected object enters the blind spot in the process of step S70 is compared with a predetermined time corresponding to the speed v2 to determine whether or not the object exists in the blind spot. By doing this, for vehicles approaching at low speed, the consideration time in the blind spot can be lengthened, and for vehicles approaching at high speed, the consideration time in the blind spot can be shortened, Only necessary warnings can be performed in consideration of the time until the blind spot is removed.

  With the above processing, even if the detected object enters a blind spot that cannot be detected by the received signal received by the receiving unit 12, the speed v2, the distance D2, and the distance D2 stored in association with the time information, and By estimating the position based on the angle θ2 and determining whether or not it is within the warning range based on the estimated position, it is possible to warn of a danger that is likely to occur due to a lane change. Become.

  As a result, if the object can be detected directly, the danger of lane change can be recognized by comparing the position of the object obtained from the detection result and the warning range. If the object is not detected directly, the past By comparing the position of the object estimated from the detection result and the warning range, the danger of lane change can be recognized, and the radar apparatus as a whole can appropriately warn of the danger of lane change.

  In the above example, the example of setting the warning range corresponding to the speed v2 has been described. However, for example, the warning range is set in association with whether or not it is in the blind spot. In this way, when warning about the lane change, the warning of the lane change is issued based on the position where the presence of the object is actually detected, or the existence of the object is actually detected. Although it is not detected, it is possible to show the driver whether the lane change warning is given based on the position estimated using the past detection result. It is possible to receive a lane change warning after recognizing As a specific presentation method, for example, when using a device that provides a flashing light at an angle that can be seen only by the driver at the base of a door mirror, etc., and emits light at the time of a lane change warning, the presence of an object is actually detected. The warning when the red lamp is turned on, and the presence of an object is not actually detected, but the warning based on the estimation based on the past detection result may be turned on.

  Of course, the warning range may be set regardless of the presence or absence of the blind spot. By doing so, an appropriate warning range is provided at the speed v2 regardless of the blind spot range. Therefore, it is possible to appropriately warn of danger when changing lanes.

  Furthermore, in the above, an example using the Doppler frequency fd2 has been described in calculating the velocity of the detected object. However, since the frequency difference between the frequencies f1 and f2 is several MHz, the frequency is obtained using the Doppler frequency fd1. In this way, substantially the same speed can be obtained. Similarly, in the above description, the example of using the phase difference between the fd1 sum signal and the fd2 sum signal has been described in calculating the distance. However, the phase difference between the fd1 difference signal and the fd2 difference signal may be used. For example, it is configured so that both can be measured, and after comparing the signal quality of the fd1 sum signal and the fd2 sum signal with the signal quality of the fd1 difference signal and the fd2 difference signal, the distance is calculated using the signal quality that is high. And the accuracy may be improved. Similarly, in the above description, the example of obtaining the angle by the ratio of the fd1 sum signal and the fd1 difference signal has been described. However, the angle may be obtained by the ratio of the fd2 sum signal and the fd2 difference signal. Furthermore, the signal quality of the fd1 sum signal and the fd1 difference signal is compared with the signal quality of the fd2 sum signal and the fd2 difference signal, and the angle is calculated using a signal having a high signal quality, thereby improving the accuracy. You may do it.

  Further, in the above, an example has been described in which when a narrow-angle switching signal is supplied, an antenna that realizes a highly sensitive antenna in a narrow-angle detection range by pairing two antennas each. Directivity can be further enhanced by adopting a configuration in which more antennas are regarded as a single antenna. Therefore, a configuration in which many antennas are regarded as a single antenna is used as a pair. You may make it do.

  Furthermore, in the above, the example in which the antennas 37-1 and 37-2 of the transmission unit 11 are switched and irradiated with radio waves based on the narrow-angle switching signal and the wide-angle switching signal has been described. Even if only the radio wave having the intensity distribution characteristic is irradiated from the transmission unit 11 without switching, the reception unit 12 simply switches the reception characteristic by connecting or releasing the RF switches 52-1 and 52-2. It is possible to switch the distribution characteristics of received radio waves.

  Further, in the above example, the example in which the narrow angle switching signal and the wide angle switching signal are sequentially switched by the area switching unit 38 every predetermined time has been described, but is the detection range set as the narrow angle detection range? The narrow-angle switching signal or the wide-angle switching signal may be output only at a timing when it is necessary to switch between the wide-angle detection range and the wide-angle detection range.

  As a result, an antenna that transmits radio waves having different intensity distributions corresponding to different detection ranges of a so-called pre-crash safety device that performs a collision preliminary operation and a so-called lane change warning device that executes a lane change warning operation. Switching with an easy structure, radiating radio waves in the switched state, and switching and receiving as an antenna with an easy-to-receive configuration corresponding to each intensity distribution characteristic radio wave, safety by both functions Can be secured.

  As described above, according to the present invention, antennas that require different intensity distribution characteristics, such as a radar device for a pre-crash safety device and a radar device for a lane change assist device, can be switched and shared with a simple configuration. Therefore, it is possible to reduce the size of the apparatus and reduce the cost.

  Incidentally, the series of monitoring processes described above can be executed by hardware, but can also be executed by software. When a series of processing is executed by software, a program constituting the software may execute various functions by installing a computer incorporated in dedicated hardware or various programs. For example, it is installed from a recording medium in a general-purpose personal computer or the like.

  FIG. 12 shows a configuration example of a general-purpose personal computer. This personal computer incorporates a CPU (Central Processing Unit) 1001. An input / output interface 1005 is connected to the CPU 1001 via the bus 1004. A ROM (Read Only Memory) 1002 and a RAM (Random Access Memory) 1003 are connected to the bus 1004.

  The input / output interface 1005 includes an input unit 1006 including an input device such as a keyboard and a mouse for a user to input an operation command, an output unit 1007 for outputting a processing operation screen and an image of a processing result to a display device, a program and various data. A storage unit 1008 including a hard disk drive for storing data, a LAN (Local Area Network) adapter, and the like, and a communication unit 1009 for performing communication processing via a network represented by the Internet are connected. Also, a magnetic disk (including a flexible disk), an optical disk (including a CD-ROM (Compact Disc-Read Only Memory), a DVD (Digital Versatile Disc)), a magneto-optical disk (including an MD (Mini Disc)), or a semiconductor A drive 1010 for reading / writing data from / to a removable medium 1011 such as a memory is connected.

  The CPU 1001 is read from a program stored in the ROM 1002 or a removable medium 1011 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, installed in the storage unit 1008, and loaded from the storage unit 1008 to the RAM 1003. Various processes are executed according to the program. The RAM 1003 also appropriately stores data necessary for the CPU 1001 to execute various processes.

  In this specification, the step of describing the program recorded on the recording medium is not limited to the processing performed in time series in the order described, but of course, it is not necessarily performed in time series. Or the process performed separately is included.

DESCRIPTION OF SYMBOLS 1 Radar apparatus 11 Transmission part 12 Reception part 13 Collision preliminary operation signal processing part 14 Collision preliminary operation control part 15 Lane change warning signal processing part 16 Lane change warning operation control part 35 RF switch 37-1, 37-2 Antenna 38 Area switching unit 51-1 to 51-4 Antenna 52-1 and 52-2 RF switch 62-1 to 62-3 Switching unit 71-1 to 71-3 FFT
72 FFT determination control unit for collision determination 73 Doppler frequency calculation unit 74 Distance calculation unit 75 Angle calculation unit 76 Collision determination unit 91-1 to 91-3 FFT
92 Lane change warning FFT timing control unit 93 Doppler frequency calculation unit 94 Distance calculation unit 95 Angle calculation unit 96 Lane change warning determination unit

Claims (5)

In a detection device for detecting an object,
Transmitting means configured to irradiate a predetermined range with radio waves, and transmitting a transmission signal by irradiating the radio waves; and
A first receiving antenna for receiving a reflected radio wave among radio waves as a transmission signal transmitted by the transmission means, each consisting of a pair of antennas arranged in a row at a first interval;
Among the radio waves as transmission signals transmitted by the transmission means, which are composed of at least two rows of antenna pairs including the first receiving antennas arranged at a second interval wider than the first interval. A second receiving antenna for receiving the reflected radio wave;
Receiving means for generating a received signal from the radio wave received by the first receiving antenna or the second receiving antenna;
A detection device comprising: detection means for detecting an object by sampling the reception signal generated by the reception means. Among the antenna pairs of at least one column constituting the second receiving antenna, the antenna pairs excluding the antenna pairs of one column arranged at the first interval constituting the first receiving antenna are: , The first receiving antenna is disposed at a second interval across the pair of antennas arranged in a row at the first interval,
Among the antenna pairs of at least one column constituting the second receiving antenna, the antenna pairs excluding the antenna pairs of one column arranged at the first interval constituting the first receiving antenna; Each further comprising connection switching means for switching between connecting or disconnecting one pair of antenna pairs arranged at the first interval, each of which constitutes the first receiving antenna,
The second receiving antenna includes one row arranged at the first interval and constituting the first receiving antenna among at least one row of antenna pairs constituting the second receiving antenna. The connection switching means connects the antenna pairs excluding the antenna pair and the antenna pairs of the respective one row arranged at the first interval, which constitute the first receiving antenna, respectively. The detection apparatus according to claim 1, wherein the detection apparatus includes at least two rows of antenna pairs including the first receiving antennas arranged at a second interval wider than one interval. The first receiving antenna and the second receiving antenna function as the first receiving antenna when the connection switching means is in a non-connected state, and when the connection switching means is in a connected state, the second receiving antenna The detection device according to claim 2, which functions as a receiving antenna. The transmission means includes
A first transmitting antenna configured to radiate radio waves to a first range that is a first angular range and up to the vicinity of a first distance;
A radio wave is transmitted to a range that includes a second angle range that is wider than the first angle range, and includes a second range that is closer to a second distance that is closer than the first distance. A second transmit antenna configured to illuminate;
Transmission antenna switching means for switching between the first transmission antenna and the second transmission antenna;
Switching signal generation for generating a switching signal instructing in synchronization with connection or non-connection of the connection switching means and switching with the first transmission antenna or the second transmission antenna by the antenna switching means The detection device according to claim 3, further comprising means. The detection means includes
First sampling detection means for detecting an object by sampling the reception signal generated by the reception means during a first predetermined time;
Second sampling detection means for detecting the object by sampling the reception signal generated by the reception means for a second predetermined time longer than the first predetermined time;
Based on the switching signal, the received signal generated from the radio wave received by the first receiving antenna is switched to the first sampling detection means and output, and received by the second receiving antenna. The detection apparatus according to claim 4, further comprising: a switching output unit that switches a reception signal generated from the radio wave to the second sampling detection unit and outputs the received signal.

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