JP2010175256A - Object detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent erroneous pairing of a target in an FM-CW type object detection device; to output correct pairing data without delay; and to thereby heighten responsiveness of control. <P>SOLUTION: When a peak frequency candidate calculation means S44 calculates a rising side peak frequency or a falling side peak frequency in the preceding-time processing cycle as a peak frequency candidate based on a this-time relative relation corresponding to an optional pairing candidate, a this-time pairing candidate decision means S48 decides a pairing candidate used for calculating the this-time relative relation as a correct pairing combination, when a difference between the peak frequency candidate calculated by the peak frequency candidate calculation means S44 and the peak frequency in the preceding-time processing cycle stored in a storage means is below a prescribed value. Since correctness/wrongness of the this-time relative relation is verified retroactively to the preceding-time relative relation, a correct this-time relative relation can be decided quickly, to thereby heighten responsiveness of control. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an object detection apparatus that detects an object using FM / CW waves.

  Ascending side obtained by frequency analysis of beat signal obtained by transmitting FM / CW wave with frequency increased / decreased with time and receiving reflected wave from object and mixing transmission signal and reception signal An object detection device configured to obtain the distance and relative speed from the frequency of the reflection peak on the descending side to the object is known from Patent Document 1 below.

Japanese Patent No. 3305624

  By the way, in order to calculate the distance and relative speed of an object with the FM / CW type radar device, the reflection peak of the upbeat signal and the reflection peak of the downbeat signal corresponding to each other of the reflected waves from the same object are combined. Is required (this is called pairing).

  Conventionally, the current position and relative speed of the target vehicle determined by pairing are calculated, the next position and relative speed are estimated from the current position and relative speed, the estimated next position and relative speed, Compare the position and relative speed actually calculated by the pairing at the current time after the elapse of a predetermined time, and if the error is within the predetermined value, the previously detected target and the current detected target are the same. Assuming there is a takeover.

  When the handover is not performed, that is, when the target is lost, the target data is continuously output a predetermined number of times by assuming that the lost target is still detected. When it is not possible to take over, it is determined that the target has been lost for the first time, and the output of the target data is stopped. In addition, when a new target is detected, the possibility that it is noise is taken into consideration, and when the target is succeeded next time, data is output as a new target.

  In the detailed description of the invention, as described in detail later with reference to FIGS. 5 to 7, when two preceding vehicles that have been continuously detected are mispaired and then paired correctly again The data of the preceding vehicle that was mispaired last time is regarded as lost and extrapolated, and continues to be output until the extrapolation process is completed after a predetermined cycle has passed, so the wrong target data for a while Control by is performed. Also, since the data of the newly paired preceding vehicle is not carried over to the previous mispaired preceding vehicle data, the newly correctly paired preceding vehicle becomes a new target and data is output immediately. Therefore, there is a possibility that control responsiveness is lowered and smooth follow-up traveling control is hindered.

  The present invention has been made in view of the above-described circumstances, and prevents mispairing of the target in the FM / CW type object detection device, and outputs correct pairing data without delay to improve control responsiveness. For the purpose.

  To achieve the above object, according to the first aspect of the present invention, FM / CW waves are transmitted to a plurality of detection areas and the reflected waves from the transmitted FM / CW waves are received. A transmission / reception means; a frequency analysis means for generating a beat signal from a transmission wave and a reception wave of the transmission / reception means; and a frequency analysis of the beat signal; and an ascending peak frequency and a decrease based on a result of frequency analysis by the frequency analysis means A peak frequency detecting means for obtaining a side peak frequency, and a relative relationship consisting of a distance to the object and a relative speed is calculated every predetermined time based on the ascending peak frequency and the descending peak frequency obtained by the peak frequency detecting means. The same object is continuously detected a predetermined number of times or more based on the relative relationship calculated this time and the relative relationship calculated last time. An object information output unit that outputs the relative relationship as object information when determined, a storage unit that stores the peak frequency obtained by the peak frequency detection unit, and a plurality of objects When a plurality of rising peak frequencies and a plurality of falling peak frequencies are obtained by the reflected wave by the peak frequency detecting means, relative relationships are calculated for all combinations of the rising peak frequency and the falling peak frequency. A pairing means for storing the combination information of the peak frequencies and the relative relationship calculated by the combination as pairing candidate information, and an ascending peak in the previous processing cycle based on the current relative relationship corresponding to any pairing candidate Frequency or descending peak frequency as peak frequency candidate The peak frequency candidate calculating means to calculate the current relationship, and the difference between the peak frequency candidate calculated by the peak frequency candidate calculating means and the peak frequency stored in the storage means is less than a predetermined value. There is proposed an object detection apparatus comprising a current pairing candidate determination unit that determines a pairing candidate used in the above as a correct pairing combination.

  According to the second aspect of the present invention, in addition to the configuration of the first aspect, the current pairing candidate determination unit stores the peak frequency candidate calculated by the peak frequency candidate calculation unit and the storage unit. If there are multiple pairing candidates whose difference from the peak frequency is less than a predetermined value, the pairing candidate having the smallest frequency difference is determined as the correct pairing combination. A device is proposed.

  According to the invention described in claim 3, in addition to the configuration of claim 1 or claim 2, the current pairing candidate determination unit includes the rising-side peak frequency candidate calculated by the peak frequency candidate calculation unit. When the difference between the rising peak frequency stored in the storage means and the rising peak frequency is less than a predetermined value, or the falling peak frequency candidate calculated by the peak frequency candidate calculating means and the falling side stored in the storage means When the difference from the peak frequency is less than a predetermined value, an object detection device is proposed in which the pairing candidate used for calculating the relative relationship this time is determined as a correct pairing combination.

  The previous up group memory M7A and the previous down group memory M7B of the embodiment correspond to the storage means of the present invention, and the current output memory M14 of the embodiment corresponds to the object information output means of the present invention. The means for realizing the process of step S7 corresponds to the pairing means of the present invention, the means for realizing the process of step S44 of the embodiment corresponds to the peak frequency candidate calculating means of the present invention, and the steps of the embodiment The means for realizing the processing of S48 corresponds to the current pairing candidate determination means of the present invention.

  According to the configuration of claim 1, when a plurality of rising peak frequencies and a plurality of falling peak frequencies are obtained by the peak frequency detecting means, the peak frequencies are stored in the storage means, and the pairing means The relative relationship is calculated for all combinations of the frequency and the descending peak frequency, and the combination information of the peak frequency and the relative relationship calculated by the combination are stored as pairing candidate information. When the peak frequency candidate calculating means calculates the rising peak frequency or the falling peak frequency in the previous processing cycle as the peak frequency candidate based on the current relative relationship corresponding to any pairing candidate, the current pairing candidate determining means When the difference between the peak frequency candidate calculated by the peak frequency candidate calculation means and the peak frequency stored in the storage means is less than a predetermined value, the pairing candidate used for the calculation of the relative relationship this time is selected as the correct pairing candidate. Confirm as a combination. In this way, since the correctness / incorrectness of the current relative relationship is verified retroactively to the previous relative relationship, the correct current relative relationship can be quickly determined and the control responsiveness can be enhanced.

  According to the configuration of claim 2, the pairing candidate determination unit this time is a pair in which the difference between the peak frequency candidate calculated by the peak frequency candidate calculation unit and the peak frequency stored in the storage unit is less than a predetermined value. When there are a plurality of ring candidates, the pairing candidate having the smallest frequency difference is determined as the correct pairing combination, so that the correct current relative relationship can be determined with high accuracy.

  According to the configuration of claim 3, the current pairing candidate determination unit determines that the difference between the rising peak frequency candidate calculated by the peak frequency candidate calculating unit and the rising peak frequency stored in the storage unit is a predetermined value. If the difference between the descending peak frequency candidate calculated by the peak frequency candidate calculating means and the descending peak frequency stored in the storage means is less than a predetermined value, it is used to calculate the current relative relationship. Since the obtained pairing candidate is determined as the correct pairing combination, the correct current relative relationship can be determined with high accuracy.

The block diagram of the vehicle control apparatus using FM * CW type radar apparatus. The figure which shows the structure of the transmission / reception means and frequency analysis means of a radar apparatus. The figure which shows the waveform and peak frequency of a transmission / reception wave when an object is approaching. The figure which shows the peak frequency detected by the peak frequency detection means. Action | operation explanatory drawing in Time1. Action | operation explanatory drawing in Time2. Action | operation explanatory drawing in Time3. The flowchart of a main flow. The flowchart of the subflow of step S7 of the main flow. The flowchart of the subflow of step S8 of the main flow. The flowchart of the subflow of step S48 of FIG. The flowchart of the subflow of step S9 of the main flow. The flowchart of the subflow of step S10 of the main flow. The flowchart of the subflow of step S11 of the main flow. The flowchart of the subflow of step S12 of the main flow. Action | operation explanatory drawing of pairing candidate calculation. Action explanation diagram of the pairing decision this time (part 1). Action explanatory diagram of the pairing decision this time (part 2). Action explanatory diagram of the pairing decision this time (part 3). Explanatory drawing of the effect of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 to 20 show an embodiment of the present invention. FIG. 1 is a block diagram of a vehicle control device using an FM / CW type radar device, and FIG. 2 is a diagram of transmission / reception means and frequency analysis means of the radar device. FIG. 3 is a diagram showing a waveform of a transmitted / received wave and a peak frequency when an object is approaching, FIG. 4 is a diagram showing a peak frequency detected by a peak frequency detecting means, and FIG. 5 is an action in Time 1 FIG. 6 is an explanatory diagram of the operation in Time 2, FIG. 7 is an explanatory diagram of the operation in Time 3, FIG. 8 is a flowchart of the main flow, FIG. 9 is a flowchart of a subflow of step S7 of the main flow, and FIG. FIG. 11 is a flowchart of the subflow in step S48 of FIG. 10, and FIG. 12 is a flowchart of the main flow. FIG. 13 is a flowchart of the subflow of step S10 of the main flow, FIG. 14 is a flowchart of the subflow of step S11 of the main flow, FIG. 15 is a flowchart of the subflow of step S12 of the main flow, and FIG. FIG. 17 is a diagram for explaining the operation of the current pairing determination (part 1), FIG. 18 is a diagram for explaining the operation of the current pairing decision (part 2), and FIG. Explanatory drawing (No. 3) and FIG. 20 are explanatory diagrams of the effects of the present invention.

  As shown in FIG. 1 and FIG. 2, the FM / CW type radar apparatus R includes transmission / reception means M1, frequency analysis means M3, current upbeat memory M4A, current downbeat memory M4B, upgrouping means M5A, Down grouping means M5B, current up group memory M6A, current down group memory M6B, previous up group memory M7A, previous down group memory M7B, current pairing confirmation means M8, current detection memory M9, group peak Calculation means M10, current output determination means M13, and current output memory M14 are provided. The frequency analysis means M3 is connected to a vehicle state determination means M2 comprising a vehicle speed sensor and a yaw rate sensor, and the current output memory M14 is connected to a vehicle control means M15 such as an automatic braking device.

  This time upbeat memory M4A, current downbeat memory M4B, upgrouping means M5A, downgrouping means M5B, current upgroup memory M6A, current downgroup memory M6B, previous upgroup memory M7A and previous downgroup memory M7B The peak frequency detection means M16 is constituted, and the current output memory M14 constitutes the object information output means of the present invention.

  Next, the transmission / reception means M1 and the frequency analysis means M3 of the FM / CW type radar apparatus R will be described with reference to FIGS.

  As shown in FIG. 2, the transmission / reception means M1 includes a timing signal generation circuit 1, an FM modulation control circuit 2, an oscillator 3, an amplifier 4, a circulator 5, and a transmission / reception antenna 6. Based on the timing signal input from the timing signal generation circuit 1, the oscillation operation of the oscillator 3 is modulated and controlled by the FM modulation control circuit 2, and the frequency is modulated into a triangular wave as shown by the solid line in FIG. The modulated transmission signal from the oscillator 3 is input to the transmission / reception antenna 6 via the amplifier 4 and the circulator 5, and FM / CW waves are transmitted from the transmission / reception antenna 6. When an object such as a preceding vehicle is present in front of the transmission / reception antenna 6, the reflected wave reflected by the object is received by the transmission / reception antenna 6. For example, when a forward object approaches, this reflected wave appears as shown by a broken line in FIG. 3A, and on the rising side where the transmission wave increases linearly, Appearing later than the transmitted wave at a lower frequency, and appearing later than the transmitted wave at a higher frequency than the transmitted wave on the descending side where the transmitted wave decreases linearly.

  The frequency analysis means M3 includes a mixer 7, an amplifier 8, an amplifier 9, and an A / D converter 10. The received wave received by the transmission / reception antenna 6 is input to the mixer 7 via the circulator 5. In addition to the received wave from the circulator 5, the transmitted signal distributed from the transmitted signal output from the oscillator 3 is input to the mixer 7. Is input via the amplifier 8. The mixer 7 mixes the transmission wave and the reception wave, thereby generating a peak frequency fup on the rising side where the transmission wave increases linearly as shown in FIG. 3B, and the transmission wave linearly. A beat signal having a peak frequency fdn is generated on the decreasing descending side. The beat signal obtained by the mixer 7 is amplified to a necessary level of amplitude by an amplifier 9 and then A / D converted by an A / D converter 10.

  In general, since a plurality of rising peak frequencies fup and a plurality of falling peak frequencies fdn are generated corresponding to a plurality of beams transmitted by the transmitting / receiving means M1, among the rising peak frequencies fup, the frequency and Data obtained by gathering data with angles close to each other by the up grouping means M5A is newly stored in the current up group memory M6A of the peak frequency detecting means M16 as the rising-side peak frequency fup (see FIG. 4A). Of the falling-side peak frequencies fdn, data obtained by combining the data close to each other in frequency and angle into the down-grouping means M5B is newly stored in the current down-group memory M6B of the peak frequency detecting means MM16 as the falling-side peak frequency fdn. (See FIG. 4B).

  Next, based on FIG. 5 to FIG. 7, problems of the prior art and an outline of the present invention for solving the problems will be described.

  In Time 1 shown in FIG. 5, the preceding vehicle A travels at a speed of 80 km / h in front of the host vehicle traveling at 80 km / h, and the preceding vehicle B travels at a speed of 40 km / h in the position 88 m ahead of the host vehicle. Suppose you are driving at At this time, the relative speed of the own vehicle and the preceding vehicle A is 0 km / h, the position of the preceding vehicle A with respect to the own vehicle does not change, and the relative speed of the own vehicle and the preceding vehicle B is −40 km / h. The car is approaching the preceding vehicle B.

  In the conventional logic, since the own vehicle and the preceding vehicle A do not have relative speeds, the ascending peak frequency fup = Aup of the preceding vehicle A stored in the upgroup memory M6A this time, and the preceding stored in the downgroup memory M6B this time. The descending peak frequency fdn = Adn of the vehicle A coincides. On the other hand, since the own vehicle and the preceding vehicle B have a relative speed of −40 km / h, the rising side peak frequency fup = Bup of the preceding vehicle B stored in the up group memory M6A this time and the current down group memory M6B are stored. Further, the descending peak frequency fdn of the preceding vehicle B does not coincide with Bdn. And in Time1, ascending peak frequency Aup and descending peak frequency Adn are correctly paired as continuous pairing (1) for preceding vehicle A, and ascending peak frequency Bup and descending peak for preceding vehicle B. The frequency Bdn is correctly paired as continuous pairing (2).

  In Time1, the logic of the present invention is the same as the conventional logic.

  Time2 shown in FIG. 6 corresponds to a state in which one cycle time has elapsed from Time1. Although the positional relationship between the vehicle without the relative speed and the preceding vehicle A has not changed, the preceding vehicle B having a relative speed of −40 km / h approaches the own vehicle. Both the descending peak frequency Bdn shifts to the lower side, and the ascending peak frequency Bup of the preceding vehicle B is slightly lower than the ascending peak frequency Aup of the preceding vehicle A.

  Thus, even if the magnitude relationship between the rising side peak frequency Bup of the preceding vehicle B and the rising side peak frequency Aup of the preceding vehicle A is reversed, the difference is small, so that the rising side peak frequency is used as continuous pairing (1). Bup and the descending peak frequency Adn are mispaired, and ascending pairing (2), the ascending peak frequency Aup and the descending peak frequency Bdn are mispaired. However, since errors in relative speed and distance due to mispairing are small, it is not known at this point that mispairing has occurred.

  In Time2, there is a difference between the logic of the present invention and the conventional logic.

  That is, according to the logic of the present invention, the preceding vehicle A is increased by comparing and verifying the data of the previous up group memory M7A and the previous down group memory M7B and the data of the current up group memory M6A and the current down group memory M6B. The side peak frequency Aup and the descending peak frequency Adn are correctly paired as continuous pairing (1), and for the preceding vehicle B, the ascending peak frequency Bup and descending peak frequency Bdn are maintained as continuous pairing (2). Paired correctly.

  Time3 shown in FIG. 7 corresponds to a state in which one cycle has elapsed from Time2. Although the positional relationship between the vehicle without the relative speed and the preceding vehicle A has not changed, the preceding vehicle B having a relative speed of −40 km / h further approaches the own vehicle. Both the lower peak frequency Bdn and the lower peak frequency Bdn are shifted to a lower side, and the rising peak frequency Bup of the preceding vehicle B is considerably lower than the rising peak frequency Aup of the preceding vehicle A.

  In this case, no misparing between the rising peak frequency Bup and the descending peak frequency Adn and no misparing between the rising peak frequency Aup and the descending peak frequency Bdn occur, and the ascending peak frequency Aup falls. Correct pairing with the side peak frequency Adn and correct pairing with the rising side peak frequency Bup and the falling side peak frequency Bdn are performed. However, since the pairing of the rising peak frequency Aup and the falling peak frequency Bdn of Time2 cannot be taken over from the pairing of the rising peak frequency Bup and the falling peak frequency Bdn of Time3, the rising peak frequency of Time2 The pairing between Aup and the descending peak frequency Bdn is still output as an extrapolation process, and control with incorrect target data is performed until the extrapolation process ends after a predetermined cycle. Furthermore, since the correct pairing of the rising peak frequency Bup and the falling peak frequency Bdn is regarded as a new target, it is not output as target data until it is succeeded next time and it is confirmed that there is no noise.

  Thus, originally, in order to keep the inter-vehicle distance with respect to the preceding vehicle B having a low vehicle speed, the deceleration control of the own vehicle should be started immediately. However, in the conventional logic, the preceding vehicle B further approaches the own vehicle. From this, the deceleration control of the own vehicle is started, and there is a possibility that jerky deceleration is performed.

  On the other hand, in the logic of the present invention, since the correct pairing between the rising peak frequency Aup and the falling peak frequency Adn and the correct pairing between the rising peak frequency Bup and the falling peak frequency Bdn are taken over, the vehicle speed is low. Deceleration control of the host vehicle for keeping the inter-vehicle distance with respect to the preceding vehicle B is started promptly, and smooth deceleration is performed.

  Hereinafter, the logic of the present invention will be described in detail based on the flowcharts of FIGS. 8 to 15 and the explanatory diagrams of FIGS.

  In step S1 of the flowchart of the main flow of FIG. 8, the vehicle state determination means M2 detects the vehicle speed and yaw rate and transmits them to the frequency analysis means M3 of the radar device R. In step S2, the current upbeat memory M4A and the current downbeat memory M4B. The current up group memory M6A, the current down group memory M6B, the current detection memory M9, and the current output memory M14 are initialized. In step S3, the upbeat signal reflected from the object by the upbeat signal transmitted from the transmission / reception unit M1 is subjected to FFT (Fast Fourier Transform) processing, and the detected angle, peak frequency, and reflection level of the current upbeat signal of the peak frequency number detection unit M16 are detected. Store in the memory M4A. In subsequent step S4, the up grouping means M5A performs grouping to collect data having similar angles to the peak frequency of the current up beat memory M4A, and stores the grouping result in the current up group memory M6A.

  Similarly, the downbeat reflection that the downbeat signal transmitted from the transmission / reception means M1 in step S5 is reflected by the object is subjected to FFT (Fast Fourier Transform) processing, and the detection angle, peak frequency, and reflection level are determined by the peak frequency number detection means M16. This time, it is stored in the downbeat memory M4B. In subsequent step S6, the down grouping means M5B performs grouping to collect data whose angles are close to the peak frequency of the current down beat memory M4B, and stores the grouping result in the current down group memory M6B.

  In step S7, a pairing subflow is executed. In step S8, a current continuous pairing confirmation subflow is executed. In step S9, a new new pairing confirmation subflow is executed. In step S10, an extrapolation processing subflow is executed. In step S12, the output determination subflow is executed. In step S12, the next process preparation subflow is executed. The contents of the subflows in steps S7 to S12 will be described in detail later.

  In step S13, the data in the current output memory M14 is output to the vehicle control means M15, and automatic braking or the like for inter-vehicle distance control or collision damage reduction control is executed.

  Next, specific contents of the “pairing subflow” in step S7 will be described with reference to FIG.

  First, in step S21, the peak frequency and reflection level of the upbeat peak signal are read from the current upgroup memory M6A, and in step S22, the angle difference from the upbeat peak signal is within ± 1.0 ° from the current downgroup memory M6B. Read the peak frequency and reflection level of the downbeat peak signal. In subsequent step S23, if the difference between the reflection level of the upbeat peak signal and the reflection level of the downbeat peak signal is 5 dB or less, it is determined that there is a high possibility that they are reflected waves from the same object. The beat peak signal and the downbeat peak signal are paired, and distance candidates and relative speed candidates are calculated from the pair.

  In step S25, if the distance candidate is 2 m or more and 150 m or less, and if the relative speed candidate is -55 m / sec or more and 55 m / sec or less in step S26, the pairing target group peak in step S27. The name and the data of both the calculated distance candidate and the relative speed candidate are stored in the current up group memory M6A and the current down group memory M6B, respectively.

  When the difference between the reflection level of the upbeat peak signal and the reflection level of the downbeat peak signal is 5 dB or less, if the difference between the reflection levels exceeds 5 dB, they may be reflected waves from another object It is because the nature is high. The reason why the distance candidate is 2 m or more and 150 m or less is that the vehicle does not approach the object at a distance less than 2 m, and the distance of the object is more than the detectable distance (about 100 m) of the radar device R This is because it does not exceed a large 150 m. The reason why the relative speed candidates are −55 m / sec or more and 55 m / sec or less is that the absolute value of the relative speed of the vehicle and the object does not exceed 55 m / sec (about 200 km / h). .

  Steps S22 to S27 are repeated until all the downbeat peak signals whose angle difference is within ± 1.0 ° are called in step S28, and steps S21 to S27 are repeated until all the upbeat peak signals are called in step S29. Step S28 is repeated.

  FIG. 16 shows the state of the current up-group memory M6A and the current down-group memory M6B in Time 2 after the execution of step S7. Each of the current up-group memory M6A and the current down-group memory M6B Candidate Aup-Adn data (relative speed = 0 km / h, distance = 40 m, confirmation flag = OFF) and pairing candidate Bup-Bdn (relative speed = -40 km / h, distance = 73 m, confirmation flag = OFF) , Pairing candidate Aup-Bdn data (relative speed = -37 km / h, distance = 76 m, confirmation flag = OFF) and pairing candidate Bup-Adn (relative speed = -3 km / h, distance = 37 m, confirmation flag) = OFF) is stored.

  Next, specific contents of the “currently continued pairing confirmation subflow” in step S8 will be described with reference to FIG.

  First, in step S41, the peak frequency is read from the current upgroup memory M6A. If there is a pairing candidate in step S42, the previous distance and relative speed are calculated from the distance candidate and relative speed candidate in step S43. Since it can be considered that the relative speed of the preceding vehicle A or the preceding vehicle B with respect to the host vehicle hardly changes during one cycle, the previous relative speed becomes the same value as the relative speed of the current relative speed candidate, and the previous distance is It is calculated by the difference between the current distance and the distance change (relative speed × 1 cycle time) between one cycle.

  In subsequent step S44, a previous up group peak candidate and a previous down group peak candidate are calculated from the previous distance and relative speed calculated in step S43. Since the distance and relative speed can be calculated from the upbeat peak signal and the downbeat peak signal, the previous up group peak candidate and the previous down group peak candidate can be calculated by performing the reverse operation.

  In the subsequent step S45, if the previous up group peak candidate and the previous down group peak candidate have a previous up group peak and a previous down group peak whose frequencies are close to each other, the peak of the current up group memory M6A and the current down group memory M6B in step S46. “Previous takeover candidate peak name”, “previous up group peak candidate and previous up group peak frequency difference”, and “previous down group peak candidate and previous down group peak frequency difference” are respectively stored in the data (FIG. 17). Steps S43 to S46 are repeated until all pairing candidates are read in step S47.

  Then, after the continuous pairing determination subflow is executed in step S48, the steps S41 to S48 are repeated until all peak frequencies are read in step S49. Next, the “continuous pairing determination” in step S48 is performed based on FIG. The specific content of “sub-flow” will be described.

  First, if there is a pairing candidate having a previous takeover candidate in step S201, and there are a plurality of pairing candidates in step S202, "frequency difference between previous upgroup peak candidate and previous upgroup peak" and "previous time" The frequency difference between the down group peak candidate and the previous down group peak ”is summed, and the pairing candidate having the smallest sum is determined as the current pairing. On the other hand, if there is only one pairing candidate in step S202, the one pairing candidate is confirmed as the current pairing in step S204.

  In the following step S205, the takeover counter value of the peak data of the previous up group memory M7A and the previous down group memory M7B of the pairing combination determined as the current pairing is incremented by 1, and the up group memory M6A and the current down group memory M6B are updated. Store in peak data. In the subsequent step S206, the detected angle, distance candidate value, relative speed candidate value, reflection level, and takeover counter value determined as the current pairing are stored in the current detection memory M9.

  In the subsequent step S207, the confirmation flag of the peak data in the current up-group memory M6A and the current down-group memory M6B, which has been confirmed as the current pairing, is turned ON, and the previous up-group memory of the pairing combination confirmed as the current pairing in the step S208 The confirmation flag of peak data in M7A and the previous down group memory M7B is turned ON.

  Next, the operation of step S8 (current pairing confirmation subflow) will be described in detail with reference to FIGS.

  FIG. 17 corresponds to Steps S41 to S47 of the subflow of Step S8 in Time2. Here, among the pairing candidates Aup-Adn, pairing candidates Aup-Bdn, pairing candidates Bup-Bdn, and pairing candidates Bup-Adn stored in the current up-group memory M6A and the current down-group memory M6B, the group peak If the pairing candidate Aup-Adn of A and the pairing candidate Aup-Bdn have a previous takeover candidate, a frequency difference between the peak frequency of the previous takeover candidate and the peak frequency of the previously detected data is calculated, and the current upgroup memory M6A and This time, it is stored in the down group memory M6B.

  That is, the peak frequencies UPA and DNA of the previous takeover candidates a and b estimated from the pairing candidate Aup-Adn of the upgroup memory M6A this time and the peak frequencies UPA and DNA of the previous detection data Aup′-Adn ′ are completely identical. Thus, the frequency difference UP on the up side is 0, and the frequency difference DN on the down side is 0. Therefore, the previous takeover candidate of the current pairing candidate Aup-Adn is Aup′-Adn ′.

  On the other hand, the peak frequencies UPA and DNA of the previous takeover candidates c and d estimated from the pairing candidates Aup-Bdn of the upgroup memory M6A this time do not match the peak frequencies UPA and DNA of the previous detection data Aup′-Bup ′. The peak frequency closest to the peak frequency of the uptake previous takeover candidate c is not the peak frequency of the previous detection data Aup ′ of the preceding vehicle A, but the peak frequency of the previous detection data Bup ′ of the preceding vehicle B. Is the peak frequency of the previous detection data Bup ′ of the preceding vehicle B. Since the peak frequency close to the peak frequency of the previous takeover candidate d of the down peak is only the peak frequency of the previous detection data Bdn ′ of the preceding vehicle B, the takeover partner of the down peak is the peak of the previous detection data Bdn ′ of the preceding vehicle B. It becomes frequency. Therefore, the previous takeover candidate of the current pairing candidate Aup-Bdn is Bup′-Bdn ′. The up-side frequency difference UP is +3, and the down-side frequency difference DN is +8.

  In FIG. 18, since there are two pairing candidates Aup-Adn and Aup-Bdn in the group peak A at step S201 and step S202 in the flowchart of FIG. 11, the process proceeds to step S203. In step S203, the sum of the frequency differences on the up side and the down side of the previous takeover candidate Aup'-Adn 'is 0 + 0 = 0, and the sum of the frequency differences on the up side and the down side of the previous takeover candidate Bup'-Bdn' is 3 + 8. Since the pairing candidate Aup-Adn is confirmed as the current pairing, the data in the memory is updated in steps S205 to S208.

  In FIG. 19, since the group peak B remains in step S49 in the flowchart of FIG. 10, the process proceeds to step S41, and the same processing as the group peak A is performed on the group peak B in steps S41 to S48.

  That is, the peak frequency UPA, DNA of the previous takeover candidate e, f estimated from the pairing candidate Bup-Bdn of the down group memory M6B this time and the peak frequency UPA, DNA of the previous detection data Bup'-Bdn 'are completely identical. Thus, the frequency difference UP on the up side is 0, and the frequency difference DN on the down side is 0. Therefore, the previous takeover candidate of the current pairing candidate Bup-Bdn is Bup′-Bdn ′.

  On the other hand, the peak frequencies UPA and DNA of the previous takeover candidates g and h estimated from the pairing candidate Bup-Adn of the down group memory M6B this time do not match the peak frequencies UPA and DNA of the previous detection data Bup′-Aup ′. The peak frequency closest to the peak frequency of the previous takeover candidate g of the up-peak is not the peak frequency of the previous detection data Bup ′ of the preceding vehicle B, but the peak frequency of the previous detection data Aup ′ of the preceding vehicle A. Is the peak frequency of the previous detection data Aup ′ of the preceding vehicle A. Since the peak frequency close to the peak frequency of the previous takeover candidate h of the down peak is only the peak frequency of the previous detection data Adn ′ of the preceding vehicle A, the takeover partner of the down peak is the peak of the previous detection data Adn ′ of the preceding vehicle A. It becomes frequency. Therefore, the previous takeover candidate of the current pairing candidate Bup-Adn is Aup′-Adn ′. The frequency difference UP on the up side is +2, and the frequency difference DN on the down side is +1.

  Since there are two pairing candidates Bup-Bdn and Aup-Adn in the group peak A in step S201 and step S202 in the flowchart of FIG. 11, the process proceeds to step S203. In step S203, the sum of the upside and downside frequency differences of the previous takeover candidate Bup'-Bdn 'is 0 + 0 = 0, and the sum of the upside and downside frequency differences of the previous takeover candidate Aup'-Adn' is 2 + 1. Since = 3, the pairing candidate Bup-Bdn is determined as the current pairing, and then the data in the memory is updated in steps S205 to S208.

  Next, specific contents of the “current new pairing confirmation subflow” in step S9 will be described with reference to FIG.

  First, in step S61, the confirmation flag = OFF peak data of the current up-group memory M6A is read. In step S62, if there is peak data of the current down-group memory M6B in which the confirmation flag to be paired = OFF, in step S63. The current pairing determination means M8 determines the peak data of the current down group memory M6B with the smallest reflection level difference as the current pairing, and calculates the distance candidate and the relative speed candidate. In the subsequent step S64, the detected angle, distance candidate, relative speed candidate, and reflection level determined as the current pairing are stored in the current detection memory M9, and the current upgroup memory M6A and the current downgroup memory determined as the current pairing in step S65. The M6B peak data confirmation flag is turned ON.

  In step S66, steps S61 to S65 are repeated until all the peak data of the confirmation flag = OFF in the current upgroup memory M6A are read.

  Next, specific contents of the “extrapolation processing sub-flow” in step S10 will be described with reference to FIG.

  First, in step S81, the peak data of the final upgroup memory M7A with the finalized flag = OFF is read, and in step S82, if there is the previous downgroup peak data with the finalized flag = OFF to be paired, the reflection level difference is determined in step S83. The smallest previous down group peak data is confirmed as the previous pairing, distance candidates and relative speed candidates are calculated, current distance and relative speed are calculated from the distance candidates and relative speed candidates in step S84, and the outer distance is calculated in step S85. The insertion counter is incremented by one. The calculation of the distance candidate and the relative speed candidate in step S84 is performed assuming that the relative speed does not change during one cycle, and the distance changes by the time of the relative speed × 1 cycle.

  In subsequent step S86, the detection angle, the calculated current distance and relative speed, the reflection level, the takeover counter value, and the extrapolation counter value are stored in the current detection memory M9. At this time, the takeover counter value stores the previous up peak value as it is. These data become extrapolated data because the extrapolation counter is incremented by one. In the subsequent step S87, the confirmation flag for the peak data in the previous up group memory M7A and the previous down group memory M7B, which has been confirmed as the extrapolation pairing in the previous time, is turned ON. Then, the steps S81 to S87 are repeated until the data of all the up-group memory determination flags = OFF is read in the step S88.

  Next, specific contents of the “output determination subflow” in step S11 will be described with reference to FIG.

  First, in step S101, the target information in the current detection memory M9 is read out. In step S102, if the takeover flag ≧ 1 and the new target is not detected for the first time, the current output determination means M13 obtains the target information in the current output memory in step S103. Store in M14. And step S101-step S103 are repeated until the target information of all this time detection memory M9 is read by step S104.

  Next, the specific contents of the “next process preparation subflow” in step S12 will be described with reference to FIG.

  First, in step S121, the target information of the current detection memory M9 is read. If the extrapolation counter value is 1 or more and 5 or less in step S122, the up group peak frequency candidate and the down group peak are calculated from the distance data and the relative speed data in step S123. Calculate frequency candidates. Subsequently, in step S124, the up-group peak candidate, detection angle, peak frequency, reflection level, takeover counter value, extrapolation counter value are stored in the current up-group memory M6A. In step S125, the down-group peak candidate is stored in the current down-group memory M6B. The detection angle, peak frequency, reflection level, takeover counter value, and extrapolation counter value are stored. And step S122-step S125 are repeated until the target information of all the present detection memories M9 is read in step S126.

  In the following step S127, all data in the current up-group memory M6A are moved to the previous up-group memory M7A and all confirmation flags are turned OFF, and in step S128, all data in the current down-group memory M6B are moved to the previous down-group memory M7B. To turn off all confirmation flags.

  When the sub-flow of step S8 to step S12 is executed in this way, the process returns to the main flow chart of FIG. 8, and the target data of the current output memory M14 is output to the control ECU of the vehicle control means M15 in step S13.

  As described above, after the occurrence of mispairing at Time 2 shown in FIG. 6, the mispairing is canceled at Time 3 shown in FIG. 7, and the correct pair of the rising peak frequency Aup and the falling peak frequency Adn is correct. Even if the ring and the rising-side peak frequency Bup and the falling-side peak frequency Bdn are correctly paired, the rising-side peak frequency Bup of Time3 is determined from the pairing of the rising-side peak frequency Aup and the falling-side peak frequency Bdn of Time2. Since the pairing with the descending peak frequency Bdn cannot be taken over, the pairing of the rising peak frequency Aup and the descending peak frequency Bdn of Time 2 is output as an extrapolation process, and is output after a predetermined cycle. Control is performed with incorrect target data until the insertion process is completed, and the rising peak frequency Bup and the falling peak Since correct pairing with the frequency Bdn is regarded as a new target, there has been a problem that it is not output as target data until it is taken over next time and it is confirmed that it is not noise.

  On the other hand, in this embodiment, in order to verify the correctness of the current pairing combination retroactively by the “currently continued pairing confirmation subflow” in step S8, even in the situation shown in FIGS. Mispairing of rising peak frequency Aup and falling peak frequency Bdn is prevented from being extrapolated and output, and correct pairing of rising peak frequency Bup and falling peak frequency Bdn is new Since it is output immediately without being held as a target, control responsiveness is improved as compared with the conventional case. Therefore, it becomes possible to start the deceleration control for the preceding vehicle approaching the host vehicle without delay, and the jerky deceleration as shown in FIG. 20 is avoided, thereby improving the comfort.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, in the embodiment, the correctness of the current pairing is based on both “frequency difference between previous up group peak candidate and previous up group peak” and “frequency difference between previous down group peak candidate and previous down group peak”. However, it is also possible to verify the correctness of pairing this time using only one of the above two.

M1 Transmission / reception means M3 Frequency analysis means M7A Previous up-group memory (storage means)
M7B Previous down group memory (storage means)
M14 Current output memory (object information output means)
M16 Peak frequency detection means S7 (pairing means)
S44 (Peak frequency candidate calculation means)
S48 (This time pairing candidate confirmation means)

Claims (3)

Transmission / reception means (M1) for transmitting FM / CW waves to a plurality of detection areas and receiving reflected waves from the transmitted FM / CW wave objects;
A frequency analysis means (M3) for generating a beat signal from a transmission wave and a reception wave of the transmission / reception means (M1) and performing frequency analysis of the beat signal;
Peak frequency detecting means (M16) for obtaining an ascending peak frequency and a descending peak frequency based on the result of frequency analysis by the frequency analyzing means (M3);
Based on the ascending peak frequency and the descending peak frequency obtained by the peak frequency detecting means (M16), a relative relationship consisting of a distance to the object and a relative speed is calculated every predetermined time, and the relative relationship calculated this time and An object information output means (M14) for outputting the relative relationship as object information when it is determined that the same object is continuously detected a predetermined number of times or more based on the previously calculated relative relationship;
In an object detection device comprising:
Storage means (M7A, M7B) for storing the peak frequency obtained by the peak frequency detection means (M16);
When a plurality of rising peak frequencies and a plurality of falling peak frequencies are obtained by the peak frequency detecting means (M16) by reflected waves from a plurality of objects, all of the rising peak frequencies and the falling peak frequencies Pairing means (S7) for calculating a relative relationship for the combination and storing the combination information of the peak frequency and the relative relationship calculated by the combination as pairing candidate information;
Peak frequency candidate calculation means (S44) for calculating the rising peak frequency or falling peak frequency in the previous processing cycle as a peak frequency candidate based on the current relative relationship corresponding to any pairing candidate;
When the difference between the peak frequency candidate calculated by the peak frequency candidate calculation means (S44) and the peak frequency stored in the storage means (M7A, M7B) is less than a predetermined value, this is used for calculating the relative relationship this time. Current pairing candidate confirmation means (S48) for confirming the pairing candidate that has been determined as a correct pairing combination;
An object detection apparatus comprising:   The current pairing candidate determination unit (S48) is configured such that a difference between the peak frequency candidate calculated by the peak frequency candidate calculation unit (S44) and the peak frequency stored in the storage unit (M7A, M7B) is a predetermined value. The object detection device according to claim 1, wherein when there are a plurality of pairing candidates that are less than, the pairing candidate having the smallest frequency difference is determined as a correct pairing combination.   The current pairing candidate determination unit (S48) is configured to determine whether the ascending peak frequency candidate calculated by the peak frequency candidate calculating unit (S44) and the ascending peak frequency stored in the storage unit (M7A, M7B). When the difference is less than a predetermined value, or the difference between the descending peak frequency candidate calculated by the peak frequency candidate calculating means (S44) and the descending peak frequency stored in the storage means (M7A, M7B) is predetermined. The object detection apparatus according to claim 1, wherein when the value is less than the value, the pairing candidate used for calculating the relative relationship this time is determined as a correct pairing combination.

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