CA2141547C - Smart blind spot sensor - Google Patents

Smart blind spot sensor

Info

Publication number
CA2141547C
CA2141547C CA002141547A CA2141547A CA2141547C CA 2141547 C CA2141547 C CA 2141547C CA 002141547 A CA002141547 A CA 002141547A CA 2141547 A CA2141547 A CA 2141547A CA 2141547 C CA2141547 C CA 2141547C
Authority
CA
Canada
Prior art keywords
signal
vehicle
circuit
output
coupled
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CA002141547A
Other languages
French (fr)
Other versions
CA2141547A1 (en
Inventor
Allan G. Pakett
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vorad Safety Systems Inc
Original Assignee
Vorad Safety Systems Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Vorad Safety Systems Inc filed Critical Vorad Safety Systems Inc
Publication of CA2141547A1 publication Critical patent/CA2141547A1/en
Application granted granted Critical
Publication of CA2141547C publication Critical patent/CA2141547C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/50—Systems of measurement based on relative movement of target
    • G01S13/52—Discriminating between fixed and moving objects or between objects moving at different speeds
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
    • G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
    • B60W2420/408—
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60Y—INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY
    • B60Y2400/00—Special features of vehicle units
    • B60Y2400/30—Sensors
    • B60Y2400/301—Sensors for position or displacement
    • B60Y2400/3017—Radars
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/06—Systems determining position data of a target
    • G01S13/08—Systems for measuring distance only
    • G01S13/32—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated
    • G01S13/34—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/50—Systems of measurement based on relative movement of target
    • G01S13/58—Velocity or trajectory determination systems; Sense-of-movement determination systems
    • G01S13/581—Velocity or trajectory determination systems; Sense-of-movement determination systems using transmission of interrupted pulse modulated waves and based upon the Doppler effect resulting from movement of targets
    • G01S13/582—Velocity or trajectory determination systems; Sense-of-movement determination systems using transmission of interrupted pulse modulated waves and based upon the Doppler effect resulting from movement of targets adapted for simultaneous range and velocity measurements
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
    • G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
    • G01S2013/9315—Monitoring blind spots
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
    • G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
    • G01S2013/932—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles using own vehicle data, e.g. ground speed, steering wheel direction
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
    • G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
    • G01S2013/9324—Alternative operation using ultrasonic waves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
    • G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
    • G01S2013/9327—Sensor installation details
    • G01S2013/93272—Sensor installation details in the back of the vehicles
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
    • G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
    • G01S2013/9327—Sensor installation details
    • G01S2013/93274—Sensor installation details on the side of the vehicles

Landscapes

  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Radar Systems Or Details Thereof (AREA)
  • Traffic Control Systems (AREA)
  • Electrophonic Musical Instruments (AREA)
  • Transmission And Conversion Of Sensor Element Output (AREA)
  • Burglar Alarm Systems (AREA)
  • Measuring Pulse, Heart Rate, Blood Pressure Or Blood Flow (AREA)

Abstract

A radar system for sensing the presence of obstacles in a vehicle's "blind spots" and generating a signal (41) to the vehicle operator indicative of the presence of such an obstacle. The system uses a common radar transceiver (7) that transmits a radio fre-quency signal directed at a blind spot of the vehicle. A Doppler shift in the received reflected frequency generally indicates that an obstacle has moved into the blind spot. Doppler frequencies attrributable to objects which are of no interest, such as stationary objects, are filtered out. Only obstacles that are traveling at approximately the same speed and direction as the vehicle are consid-ered to be of interest, and will cause the blind spot sensor to generate an indication that an obstacle is present in the blind spot.
The indication is preferably an unobstrusive illuminated indicator which is affixed to one of the vehicle's mirrors. An obstrusive audible indicator is provided which creates an audible tone, whistle, or buzz when an obstacle is present and the vehicle's turn sig-nal is active.

Description

~ WO 94/0494l PCl /US93/07504 1. 21~547 ~MART BLIND 8POT BEN~OR
sA~ KuuNL~ OF THE lDlV~n.
1. Field of the Invention ~his invention relates to automotive radar systems, and more particularly to a radar 6ystem for sensing the ~ s~ e of obstacles in a vehicle's "blind spots".
10 2. Description of Related Art A continuing problem that presents itself to operators of automotive vehicles is the dif f iculty in seeing obstacles near the vehicle but in a location that is difficult to observe from the driver's seat. Such 15 regions are commonly referred to as "blind spots". For example, the angles between 9O and 170 from the forward direction of a vehicle (i.e., to the right of the vehicle and slightly behina the operator thereof ) is a common blind spot, particularly for large vehicles 20 such as buses and trucks. This right-side blind spot is a source of numerous accidents when a drive makes a right-hand turn or a right lane change and does not see another vehicle in the blind spot. Another common blind spot is the rear of a vehicle when backing up.
The most common solution to the problem of blind spots has been to use mirrors to aid the operator of the vehicle in det~rminin~ whether obstacles are present in a blind spot. Such mirrors have been made in a variety 30 of shapes and mounted in various locations to provide the operator with the greatest ability to detect obstacles in particular blind spots. For example, it is common place today to see a concave mirror mounted to the right side of a vehicle aimed at the right-side 35 blind spot. While mirrors provide the operator with some information regarding the presence of obstacles in certain of a vehicle's blind spots, but they are less WO 94/04941 PCI`/US93/07504 ~
~21~15~7 2.
useful at night and under adverse weather conditions.
EIence, a more complete and satisfactory solution is still sought by many.
5 A known alternative to the use of mirrors to detect obstacles in a vehicle's blind spot is to mount a camera on the vehicle to provide the operator with a visual image of obstacles in the vehicle's blind spot.
However, this solution is complex and expensive, 10 requiring a video camera and video monitor. Further, a video monitor can present a complex image that must be interpreted by a driver, and such monitors can be distracting. Noreover, like mirrors, such camera systems are less useful at night and under adverse 15 weather conditions.
Therefore, there is presently a need for a simple, and ; nc-~ns:ive solution to the problem of detecting hazardous obstacles in the blind spots of a vehicle.
20 Such a solution should also be useful at night and under adverse weather conditions. The present invention provides such a solution.

~WO 94/0494l PCI/US93/07504 3 2`1~1S~7 8~MMaRY OF THE 1~ ~ lUN
The present invention is a simple, compact, and ; nPyrpncive radar detection system conf igured to detect 5 the presence of an obstacle in a vehicle's blind spots and generate a signal to the vehicle operator indicative of the presence of such an obstacle.
The system uses a common radar transceiver that 10 transmits a radio frequency (RF) signal directed at a blind spot of the vehicle. The signal is reflected off any obstacles that are present in that blind spot region. The frequency of the transmitted signal is compared with the frequency of a reflection of the 15 transmitted signal to determine whether the reflected signal has been Doppler shifted. A Doppler shift in the frequency generally indicates that an obstacle has moved into the blind spot.
20 Analog filters and digital circuits are used to filter out Doppler LLe~uèl.cies attributable to objects which are of no interest, such as stationary objects (for example, parked cars, road signs, and road side trees).
only obstacles that are traveling at approximately the 25 same speed and direction as the vehicle are c~nci-lPred to be of interest. Therefore, it is only thêse obstacles that will cause the blind spot sensor to generate an indication that an obstacle is present in the blind spot.
The indication that is communicated to the vehicle operator is preferably an unobtrusive i 1 ltlm;n~ted indicator which, in the pref erred ~ i r L of the present invention, is affixed to or mounted near one of 35 the vehicle's side mirrors. Having the indicator affixed in this manner allows it to be seen by a normal, practiced motion of the driver's head.

21~1~4~ --4.
E~owever, the operator is not distracted or disturbed by the frequent indications of obstacles which may occur under normal tra~f ic conditions, and which are of little or no interest to the operator unless a maneuver 5 is planned which would cause the vehicle to come into contact with the obstacle. In addition to the illllm;n~ted indicator affixed to or mounted near a side mirror, an obtrusive audible indicator is provided in the preferred F ' ';-- t of the present invention which 10 creates an audible tone, whistle, or buzz when an obstacle is present and the vehicle's turn signal is active .
A malfunction detector is also included in the 15 inventive blind spot sensor. The malfunction detector monitors an output of a sample and hold circuit to ensure that an output voltage from the sample and hold circuit is within expected limits, thereby det~rm;n;n7 whether the system is functioning properly.
The details of the preferred ~ a;r l,s of the present invention are set forth in the i~ ying drawings and the description below. once the details of the invention are known, numerous additional innovations 25 and changes will become obvious to one skilled in the ~rt .

~ WO 94/04941 PCl /US93/07504 2141~7 5 BRIEF DE8CRIPTION OF THE m~l~
FIGURE 1 is a simplified block diagram of the present invention .
FIGURE 2 is a detailed block diagram of the signal processing section of the present invention.
FIGURE 3 is a flow chart of the procedure followed by 10 the preferred ~mho~lir 1_ of the present invention upon detection of an obstacle.
FIGURE 4 is a simplified schematic of the indicator circuit of the pref erred ~mho~ l. of the present 15 invention.
Like ref erence numbers and designations in the various drawings ref er to like elements .
2 1 4 1 5 ~ ~ PCI/I~S93/07~04 ~
6.
D~TT T~n DE8C~IPTION OF TIIE lD V~
Throughout this description, the preferred '- i- L
and examples shown should be considered as exemplars, 5 rather than as limitations on the present invention.
FIGURE 1 is a block diagram of the preferred o-~o~ nt of the present invention . The pref erred ~mho~; ~
shown in FIGURE 1 ; nrll~A~C a radar transceiver which 10 .1PfPrm;n~c the E,L,:sel.~e or absence of a target.
Eowever, in an alternative ~mhorl;~ -l t of the present invention, the transceiver may emit and receive ele~:LL, ic signals to other frequencies, or signals other than ele~LL gnPtic radiation, such as 15 ultrasonic radiation. Such ultrasonic transceivers are well known in the art and are used for detection of objects in the context of alarm systems, for example.
In FIGURE 1, a Gunn diode 1 generates an radio 20 rLe yU~ y (RF) transmit signal based upon an input provided to the Gunn diode 1 from a timing control circuit 3. The timing control circuit 3 pulses for n duration of lO ll5 at a rate of lO kEz ( i . e ., the timing control signal, and conseyuently the RF transmit signal 25 output by the Gunn diode 1, has a 10% duty cycle). A
109c duty cycle was chosen to optimize the energy efficiency of the system. The RF transmit signal is coupled to an RF coupler circuit 5 which permits RF
energy to be coupled from the Gunn diode 1 to an 3 O antenna 7 and an RF mixer diode 9 .
The antenna 7 directs the RP transmit signal along a side of a vehicle upon which the radar system is mounted. In the illustrated : ~ ';- L of the present 35 invention, a single antenna is used to transmit a single RF signal, and is mounted to provide the most effective C~V~LC~ of a blind spot of a particular ~ WO 94/04941 PCI/US93/07504 7.
vehicle. However, in an alternative embodiment of the present invention intended f or use with large vehicles, such as busses, a plurality of antennas may be used to ensure that obstacles which are present anywhere within 5 the vehicle' 5 blind spots are detected. The RF
transmit signal is reflected off obstacles in the path of the signal. The antenna 7 receives a portion of the reflected signal. If an obstacle which reflects the transmit signal is in motion relative to the antenna 7, 10 a Doppler frequency shift occurs between the transmitted signal and the received signal. Doppler shifting is a well-known rh~n~ by which a signal which is reflected off an object which is approaching the source of the signal is compressed, thereby causing 15 the Lr t:~Ut~ y of the signal to be shifted upward.
Likewise, the frequency of a signal that is reflected off an object that is moving away from the source is shifted downward .
20 The reflections of the RF transmit signal which are received by the antenna 7 are coupled to the RF coupler circuit 5, which in turn couples the received ref lections to the RF mixer diode 9 . The mixer diode 9 generates an output which has a frequency equal to the 25 difference between the frequency of the RF transmit signal and the received reflections of the RF transmit signal. In the preferred Prho-li L of the present invention a Doppler detection module, such as part no.
DRO2980 r~rkp~pd by Alpha Industries, ;nclllA~c the RF
30 antenna 7, the RF coupler circuit 5, the Gunn diode 1, and the mixer diode 9 in a single housing.
The output of the mixer diode 9 is coupled to a signal procPccin~ section 11. The signal processing section 35 ll amplifies, time demultiplexes, and filters the output of the mixer diode 9. The signal procpcsing section 11 is coupled to a central processing unit -WO 94/04941 PCI /I )S93/07504 21415~ 8.
(CPU) 31 that det-~rm; nPq whether the output of the signal processing section 11 represents an obstacle of interest in the blind spot. The CPU 31 i5 coupled to an indicator circuit 41 which presents warnings to the 5 vehicle operator.
FIGURE 2 shows a detailed block diagram of the signal processing section 11 of the preferred ' ';- ~ of the present invention. An adjustable preamplif ier 10 (preamp) 21 receives the output from the mixer diode 9.
The preamp 21 has a very low f requency response of approximately 1/2 Hz, thereby permitting very low frequencie6 to be amplified. By adjusting the gain of the preamp 21, the sensitivity of the system is 6et to 15 permit only those obstacles which are in the immediate presence of the vehicle to be ~ tected. Since the signal strength of the reflection drops by the square of the distance (i.e., p e 1 / d2), proper adjustment of the preamp 21 is very effective in limiting the range 20 of the blind spot sensor. For example, experimentation has shown that a motorcycle will be detected in the lane ad; acent to a vehicle equipped with the pre6ent invention at a distance of approximately 3 feet, while an automobile of average size will not be detected as 25 being present if there is an empty lane between the aut, ,~ l P and the radar-equipped vehicle.
In an alternative Pmho~ L of the present invention, the distance to an obstacle can be detected and 30 obstacles that are beyond a specified range can be disregarded. Thus, obstacles that are outside the blind spot (i . e., two lanes from the vehicle) but which are highly ref lective will not cause the blind spot sensor to falsely indicate the ~I=stllce of an obstacle 35 in the blind spot. In one such alternative ~ L, a continuous wave (CW) rL~u~ .;y-modulated (FM) ramped modulation signal is applied to the input of the Gunn WO 94~04941 PCI /US93/07504 21~54~
diode 9, causing the Gunn diode 9 to change frequency in a linearly proportional relationship to time for a first period. After the first period, the CW FM ramped modulation signal causes the Gunn diode 9 to change 5 frequency in an inverse linearly proportional relation-ship to time for a second period, which may be equal to the f irst period .
Because there is a time delay between the tr:~-nF~ inn lO of a signal and the receipt of the reflection of that signal off an obstacle, the delay being proportional to the di6tance from the transceiver to the obstacle, the frequency of the received reflection differs from the transmit frequency by an amount that is proportional to 15 the time required for the signal to travel to the obstacle and return. Therefore, the C, ~ u~ ;y iS also proportional to the distance between the antenna 7 and the obstacle. Because the CW FM ramped modulation signal causes the frequency of the transmit signal to 20 ri~e for a period of time and then to fall for a period of time, the frequency shift caused by the Doppler -- can be distinguished from the ~requency shift caused by the range of the obstacle. CW FM
ramping modulation range detection schemes, such as 25 described here, are well known in the art.
In another such alternative ~mho~l;r-nt of the present invention, the receiver circuitry is gated off a specified amount of time after the ke~;nn;ng of a 30 transmission pulse . If the specif ied amount of time is equal to the amount of time required for the transmit signal to reach the outer limits of the range of interest, only those obstacles that are within the range of interest are detected.
In the pref erred ~mhofl; - t of the present invention, the output of the preamp 21 is coupled to a sample and WO 94/04941 PCI`/US93/07504~
21~15~ lo.
hold circuit 23. The sample and hold circuit 23 samples the output of the preamp 21 at a rate and for duration equal to the rate and duration at which the transmit signal is pulsed by the Gunn diode l (i.e., 5 for lO~s at a rate of lO kHz in the preferred embodi-ment). The sampling is synchronized to the transmission of the transmit signal by applying the same ~y...l.lullization signal from a pul6e generator clrcuit 25 to both the Gunn diode l and the sample and 10 hold circuit 23. The ~y.,~:l.Lu..ization signal causes the Gunn diode 1 to generate the transmit signal when the synchronization signal is at a relatively high voltage level, and also gates the sample and hold circuit 23 to sample the output of the preamp 21 during the same 15 period. Each time the sample and hold circuit 23 samples the output of the preamp 21, a voltage level is LecuLded. Thus, the output of the sample and hold circuit 23 -is a series of voltage levels which inuL~ L or deuLl L every 100~L5. The voltage levels 20 L~ ~L~se--L the phase difference (i.e., Doppler shift) between the transmit signal and the received signal applied to the mixer diode 9 during each sample period.
The output of the sample and hold circuit 23 is coupled 25 to a low pass filter 27. The low pass filter 27 of the pref erred Pmho~ nt of the present invention has a 3 dB cutoff frequency of about lO0 ~z. The low pass filter 27 serves three purposes: 1) to smooth the signal output by the sample and hold circuit 23 by 30 removing high-r~e.lue... y ~nPnts of the output waveform; 2) to reduce noise, thus improving sensitivity without increasing RF power; and 3) to eliminate signals which le,uLese--L objects moving rapidly relative to the vehicle, including stationary 35 objects. Since the purpose of the present invention is tû determine whether arl obstacle which would otherwise go undetected by the operator is present in a blind ~ WO 94/04941 2 1 4 1 5 4 7 PCI/US93/07~04 11 .
spot of the vehicle, those obstacles which move rapidly through the blind spot are not of interest. It is assumed that obstacles that are moving rapidly through one of the vehicle's blind spots will be seen before 5 entering the blind spot, or will pass through the blind spot before the operator causes the vehicle to perform a maneuver which would present a danger due to the presence of that obstacle.
10 The low pass f ilter 27 is coupled to a square wave generator 29 which generates a square wave signal that alternates between O volts and 5 volts. The frequency of the signal output by the square wave generator 29 is determined by the frequency of the input to the sguare 15 wave generator 29 from the low pass filter 27. A
square wave transition is output by the square wave generator 29 whenever an obstacle has been dete~t~d.
In the preferred pmho~lir L of the present invention, 20 the square wave generator 29 is a comparator circuit with hysteresis. The hysteresis provides noise immunity, prevents the comparator from oscillating, and limits range detection to a def ined distance . Thus, when the input to the square wave generator 29 rises to 25 cross a first relatively high threshold, the output of the square wave generator 29 tran6itions to a 5 volt level . When the input to the square wave generator 2 9 falls below a second relatively low threshold, the output of the square wave generator 29 transitions to a 30 o volt level. The creation of a square wave output provides noise immunity and allows the output to be further processed by the CPU 31.
Because some of the circuitry used in the present 35 invention operates more efficiently when power i8 sl~rpli-~d from a bipolar power supply (i.e., both positive and negative voltages), a virtual ground WO 94/04941 _ PCr/US93/07504 ~
2141~7 12.
circuit 33 is included in the illustrated Pmho~ t of the present inYention. The virtual ground circuit 33 works in conjunction with a voltage regulator 35 to supply the power requirements of the illustrated 5 Pmho~l; r ~ of the present invention . Nost automotive vehicles today include a 12 volt battery which powers the starter motor and the electrical system when the engine of the vehicle i8 not operating, and a voltage generator or alternator which recharges the battery and 10 supplies current to the vehicle electrical system when the engine is operating. The voltage regulator 35 of the present invention receive6 power from the 12 volt vehicle power source and generates a stable 5 volt output. The 5 volt output of the voltage regulator 35 15 is applied to those - -nts of the present invention which operate from a positive 5 volt source, and to the virtual ground circuit 33. The virtual ground circuit 33 creates a 2 . 5 volt output which acts as a virtual ground ref erence f or those c within the 20 present invention that require both positive and negative supply voltages. Thus, the 5 volt output of the voltage regulator 35 is 2 . 5 volts positive with respect to the virtual ground reference, and earth ground (0 volts) is 2.5 volts negative with respect to 25 the virtual ground reference. Such virtual ground circuits are well known in the art.
A malfunction detector circuit 39 is coupled to both the sample and hold circuit 23 and the square wave 30 generator 29. The malfunction detector circuit 39 generates an output that indicates whether the present invention is operating properly. When the present invention is operating properly, a direct current (DC) of f set is present at the analog output of the sample 35 and hold circuit 23. The DC offset is stripped from the analog output by capacitively coupling the analog output from the sample and hold circuit 23 to the low ~ WO 94/0494l 2 1 ~ ~ 5 ~ 7 pcr/us93/07504 13 .
pass filter 27. However, the DC portion of the output of the sample and hold circuit 23 is present in the output that is coupled to the malfunction detector 39.
In the preferred emhorl; t of the present invention, 5 if the DC offset i8 not above a 6pecified voltage, the malfunction detector 39 generate6 and 6end6 a gate control signal to the 6quare wave generator 29 which decouple6 the square wave generator 29 from output circuitry of the signal processing section 11. A
10 voltage divider circuit coupled to the signal processing 6ection 11 output cau6es the output of the signal processing 6ection 11 to be 2.5 volts. Since, under normal conditions, the square wave generator 29 outputs only 0 volt6 or 5 volts, the pre6ence of a 2 . 5 15 volt output from the square wave generator 29 indicate6 a problem.
The output of the square wave generator 29 is coupled to a dual edge- triggered memory register (flip-flop) 20 37, which is used to establish a "persistence period", as described below. A "persistence period" is def ined in the pref erred . ~ t as the amount of time that it takes the vehicle upon which the radar system in mounted to travel 15 feet. When an obstacle is first 25 ~ tec~ed, ~s det~rminc~d by a transition at the output of the square wave generator 29, the CPU 31 wait6 the per6istence period before r~pon~9;n~ to additional transitions. During the persi6tence period, no warning6 are 6ent to the driver indicators. After the 30 end of the persistence period, a warning is sent after each #uch transition if the tran6ition occur6 either within one 6econd after the end of the last persistence period or two seconds after a prior warning was sent.
otherwise, a new persistence period cycle begins.
If it is det~rmin~d that there is an obstacle persists in the blind spot, a indication is presented to the -WO 94/04941 2 1 4 1 5 4 ~ pcr/us93/07s04~
14 .
operator of the vehicle. In the preferred ~mho~;r L
of the present invention, three type6 of indications are used. If the vehicle's turn signal becomes active (as detected by a position sensor coupled to an input 5 of the CPU 31), and an obstacle is ~t~rt~cl in the blind spot, an audible alarm sounds (e.g., emits an audible tone, whistle, or buzz) and a red visual indicator ~ m; n~teS . If the turn signal is not active and an obstacle is detected in the blind spot, l0 the audible alarm is not activated, but the red visual indicator illuminates. If no obstacle is detected, a yellow visual indicator illuminates and the red indicator is inactive (illumination of the yellow indicator signif ies that the blind spot sensor and 15 circuit are active. ) In an alternative ~ L of the present invention, sensors to detect the steering wheel position and/or the position of the turn signal are used to provide an 20 indication that the operator is attempting to turn or change lanes. Other sensors may also be used to aid in the ~ t~rm;n~tion as to when the operator is attempting to cause the vehicle to enter a blind spot region. The system can be configured, if desired, to detect turning 25 indicated by the position of the turn signal and/or by sensing the position and m ~r~ L of the steering wheel, and to activate the audible alarm only if a turn is indicated in the direction of a blind spot in which an obstacle is present.
FIGURE 3 is a flow chart of the L/~O~ dULe followed by the preferred ' ~ L of the present invention for ~lDt~rm; n; n g whether to warn the vehicle' s operator of the presence of an obstacle in a monitored blind spot.
35 When a transition from 0 volts to 5 volts or from 5 volts to 0 volts occurs, a flag within the register 37 is set. In the illustrated ~-ho~i l. of the present --~ WO 94/04941 2 i I I 5 4 ~" ;; PCI/US93/07504 invention, the CPU 31 polls the register 37 at regular intervals to determine whether the register 3 7 has been set (STEP 301). (In an alternative ~mho~;r l. of the present invention, the CPU 31 is interrupted when the 5 flag within the register 37 is set. ) Once the CPU 31 detects that the f lag within the register 3 7 has been set, the CPU 31 resets the flag (STEP 302) and ceases polling the regi6ter 37. The CPU 31 is coupled to a spee ' ter which measures the ground speed of the 10 vehicle. The CPU 31 uses the vehicle speed to calculate how long it will take the vehicle to travel 15 feet (i.e., the persistence period) (STEP 303), and sets a timer to l~ti- - ~ uL" at the end of the calculated amount of time (STEP 304). Once the timer times out (STEP 305), the CPU 31 sets a one second and a two second flag timer (STEP 306), and reset6 the flag in register 37 to ensure that any new transitions that may have o.~;u..~:d during the persistence period are cleared ( STEP 3 07 ) .
In an alternative ~ 'i L of the present invention, one timer is used to indicate the amount of time elap6ed after the flag in the register 37 is reset.
Thus, the same timer which was used to determine when 25 the persistence period has elapsed is reset and can be read at any time to determine the amount of time elapsed since the flag in the register 37 was reset.
The timers of the preferred ~ ;r L of the present 3 0 invention are integrated into the CPU 31. However, one or more of the timers may be implemented in external - circuitry.
- In the illustrated ~ t of the invention, the CPU
35 31 once again begins polling the flag within the register 37 after the persistence timer has timed out (STEP 308). By 51lcp~n~1;n~ the polling of the register 16 .
37 for the persistence period, and rPcettin~ the register 37 at the end thereof, the syste~ effectively ignores transitions at the output of the square wave generator 29 caused by reflections of the RF transmit 5 signal off stationary obstacles, such as parked cars and road signs, which are present in the blind spot for less than the persistence period.
The CPU 31 checks whether a warning is presently being 10 displayed (i.e., in the preferred ~ of the present invention, whether the red indicator is illuminated) (STEP 317) while waiting for the flag in the register 37 to be set. If a warning is presently being displayed, the CPU 31 determines how long it has 15 been since the warning was last activated. If the warning has been on display for more than one second without being reactivated ( STEP 3 18 ), the CPU 3 1 causes the warning to cease being displayed (STEP 319). The CPU 31 also ~PtQrminPs whether an audible alarm has 20 been 591~n~;n~ for more than one second without being reactivated (STEP 320), and causes the audible alarm to cease if reactivation of the alarm has not OCI.:UL L ~d in the last one second ( STEP 3 21 ) .
25 If the CPU 31 tlP~Prm;nPC that the flag in the register 37 is set (STEP 308), the CPU 31 resets the flag (STEP
309) and checks how long it has been since the persistence timer tir~ u~ (STEP 310). If more than two seconds have passed since the persistence timer 30 t;~ ,u~, the process returns to STEP 303 and suspends the polling of the register 37 once again. Thus, if an obstacle ref lects the RF transmit signal back to the antenna 7, causing the output of the square wave generator 29 to transition, but no further reflections 35 are ~Ptect~Pd for over two seconds, the system ~ehaves zls if the neYt transition of the square wave generator 29 is unrelated to the last transition, i.e., polling ~ WO94/04941 2141547 PCI/US93/07504 17 .
is suspended to ensure that the obstacle that cau6ed the transition persists for more than the time required to travel 15 feet.
5 However, if the transition has oc~uLL~d within two seconds of the tir~ ouL of the persistence timer (i.e., the two-second persistence timer has not timed-out), then the CPU 31 checks whether one second has elapsed between the end of the persistence period and the 10 latest transition (STEP 311). If more than one second has elapsed, then the CPU 31 checks whether more than 2 seconds have elapsed since the last warning has been reactivated (STEP 312). If more than two seconds have elapsed, then the system returns to STEP 303 and 15 :,u~ ds polling of the flag in the register 37 for the duration of a newly calculated persistence period.
Otherwise, a one second warning timer and a two second warning timer are set (STEP 313), and the warning is reactivated (i.e., in the preferred ~mho~l; L of the 20 present invention, the yellow indicator is turned off and the red indicator is turned on) (STEP 314). It should be understood that, as with the flag timers of step 306, the warning timers may be implemented as a single timer and may be either discrete timers or 25 integrated into the CPU 31.
In the preferred - ': 'i L of the present invention, the CPU 31 det~rmin~ whether the vehicle turn signal is active (STEP 315). If so, an audible alarm is 30 activated to indicate that an obstacle is present in the blind spot and that turning the vehicle may be hazardous (STEP 316). After reactivating the warning and resetting the warning timer, the system returns to STEP 308 to await the next setting of the flag in the 35 register 37.

WO 94/04941 PCI`/US93/07~04 214~547 18 .
By det~rminin~ whether a warning has been activated within the last two seconds, and if so, then extending the period before which the system resets the persistence timer, an obstacle in the blind spot which 5 is moving at a very slow speed relative to the vehicle is not filtered out of the system due to the long duration between transitions of the square wave generator 29 output. For example, an obstacle in the blind spot moving at a relative speed that ~L OdUCeS a 10 Doppler frequency of less than l/2 Hz generates transitions at the output of the square wave generator 29 at twice the Doppler frequency, i.e., less than 1 Hz. Therefore, the time between transitions is greater than l second. Increasing the amount of time allowed 15 between the t i - - u uL of the persistence timer in STEP
305 and the next OC~;ULLdnCe of a transition tas deter-mined by detecting that the flag in the register 37 has been set) increases the low frequency 1 ~:.~u..se of the system. If it i5 already ~l~t~rmin~l that an obstacle 20 was very recently present (i.e., the warning timer has not yet t;~ ,uL), then the pos~ihi 1 ity that an obstacle of interest caused the transition is much greater.
25 FIGVRE 4 i8 a simplified schematic of a preferred indicator circuit 41 for controlling the i l lllmin~tion of two warning indicators 407, 408, one of which would be yellow and the other red. A power supply is coupled to two resistors 401, 402 and a photo 6witch 403. A
30 warning control input 404 coupled to a control output of the CPU 31 controls the rnn~lllct ivity of a bipolar transistor 405, which in turn controls the cnn~uct;vity of a field effect transistor (FET) 406. By controlling the bipolar transistor 405 and the FET 406, the warning 35 control input 404 controls the current flow through the two warning indicators 407, 408. The photo switch 403 is capable of bypassing the current limiting resistors ,~ WO 94/04941 2 1 ~ 1 5 ~ 7 PCI/US93/07S04 401 and 402, and thus increasing the lllrin~nre of each of the warning indicators 407, 408. The photo switch 403 is turned on (i.e., conducts current) when the ambient light is greater than a pr~ t~rm; n~d threshold 5 amount. Therefore, the lllmin~nre is automatically controlled as a function of the ambient light, such that the warning indicators 407, 408 are visible in full 6unlight, and are dimmed for nighttime conditions.
Diodes 409, 410 divide the current that passes through 10 the photo switch 403 when the photo switch is conducting, while isolating the current that flows through the resistors 401, 402 and indicators 407, 408 when the photo switch is not conducting.
15 In the preferred ~ ir L of the present invention, the visual warning indicators 407, 408 are very high lllmin~nre light emitting diodes (LEDs) placed on or in close proximity to a mirror on the same side of the vehicle as the blind spot sensor, such that when the 20 ~ LatU~ looks in the mirror the warning indicators 407, 408 are prominent. Having the warning indicators 407, 408 affixed to an existing mirror allows it to be seen by a normal, practiced motion of the driver's head. However, the operator is not distracted or 25 disturbed by the frequent indications of obstacles which may occur under normal traf f ic conditions, and which are of little or no interest to the operator unless a maneuver is planned which would cause the vehicle to come into contact with the obstacle.
The present invention thus provides a simple, in~ Pn~:ive, and complete solution to the problem of t~rt; n~ hazardous obstacles in the blind spots of a vehicle. In addition, because the system generates and 35 senses its own ele- LL, _ ?tiC waves, the present invention works at night and under most adverse weather conditions. R~fl~rt~d signals attributable to objects WO 94/04941 PCI`/US93/07504 20 .
which are of no interest, such as stationary objects, or which do not persist a minimum amount of time, are ignored. Only persistent obstacles that are traveling at approximately the same speed and direction as the 5 vehicle are considered to be of interest, and will cause the blind spot sensor to generate an indication that an obstacle is present in the blind spot. In the preferred omho~ the indicators give a first, non-obtrusive indication to signify that the blind spot lO sensor i5 active, a second, somewhat obtrusive indication to signify that a persistent obstacle i6 present in the blind spot, and a third, more obtrusive indication to signify that a persistent obstacle is present in the blind spot if the driver has activated 15 the turn indicator.
While a number of omh9~ Ls of the present invention have been described, it will be understood that various modifications may be made without departing from the 20 spirit and scope of the invention. For example, the transceiver may transmit and receive ultrasonic radiation. Also, the RF transmit frequency may be a multiple frequency signal having a multitude of rLt~uellcies, each frequency being time division multi-25 plexed with the others. Fur~hr- ~, the RF transmit frequency may be a continuous wave signal.
Additionally, the RF transmit signal may be a pseudo-pulse signal in which the Gunn diode 9 is not turned completely off, but rather alternates between two 30 discrete power levels. Still further, a wide variety of -- ~ni, or methods can be used for warning the vehicle operator of the presence of an obstacle, such as bells, physical vibrations, visual indications placed on the ~chhc~rd or win~hi~ and/or use of a 35 mirror in.c.L~uLclting a material (e.g., lead lanthanum zirconate titanate, or PLZT) which changes color (i.e., turns red) or otherwise changes optical properties when W094/04941 21. PCI`/US93/07504 the smart blind spot sensor detects an obstacle in the blind spot. ll ,~ eo~ " the smart blind spot sensor can use multiple Doppler detection modules to provide coverage of multiple blind spots. In such a 5 configuration, a single CPU 31 can be used to poll and control all of the modules, thus reducing the cost of such a system by time-sharing the CPU 31 between the multiple modules. Still further, the values disclosed above for the persistence periods, time-out periods, 10 duty-cycle, etc., may be varied as desired, and are not limited to the particular values disclosed.
Accordingly, it is to be understood that the invention is not to be limited by the specific illustrated 15 pmhorlir ~, but only by the scope of the ~rp~nrle claims .

Claims (5)

22.
1. A system for detecting the presence of targets moving at slow speeds relative to the vehicle upon which the system is mounted and adjacent to, and on at least one side of, the vehicle upon which the system is mounted, including:
(a) a transceiver for emitting signals along side a vehicle upon which the system is mounted and for receiving reflections of the emitted signals;
(b) a Doppler circuit, coupled to the transceiver, for generating a Doppler signal having a frequency equal to the difference between the emitted signal and the received reflections;
(c) a signal processing section including:
(1) an amplifier, coupled to the Doppler circuit, for amplifying the Doppler signal such that only targets within a range of approximately 15 feet of the transceiver are detected;
(2) a sample and hold circuit, coupled to the amplifier, for sampling the output of the amplifier during periods concurrent with the emission of the emitted signals and generating a signal having a voltage level that is proportional to the phase difference between the emitted signal and received reflections;
(3) a low pass filter, coupled to the output of the sample and hold circuit, for filtering high frequency components and signals which represent objects moving rapidly relative to the vehicle upon which the system is mounted from the signal output by the sample and hold circuit;
(4) square wave generator coupled to the low pass filter for generating a square wave output having a frequency equal to the filtered signal;

23.
(5) malfunction detector circuit, coupled to the output of the square wave generator and the output of the sample and hold circuit, for sensing the level of the direct current offset of the signal generated by the sample and hold circuit, to determine when the system is operating within specified limits, and indicating a malfunction in the detection system when the system is not operating within the specified limits;
(6) a persistence period circuit, coupled to the square wave generator, for generating an output equivalent to the output of the square wave generator when an object is present for a predefined minimum persistence period;
(d) an indicator circuit, coupled to the persistence period circuit, for receiving the output of the persistence circuit and indicating to an operator of the vehicle on which the system is mounted, the presence of an object which is detected for a period which is longer than the persistence period.
2. The system of claim 1, wherein the malfunction detector circuit is coupled to the indicator circuit for indicating to an operator of the vehicle on which the system is mounted when the system is operating within specified limits.
3. The system of claim 1, wherein:
(a) the indicator circuit is coupled to at least one automotive turn signal;
(b) the indication of the presence of an object is by means of a visual indicator; and (c) an audible alarm to the operator, in addition to the visual indication, is presented to the operator when an object is detected on the side of the vehicle to which the turn signal signals a turn.

24.
4. The system of claim 1, wherein the low pass filter has a 3 decibel cutoff at approximately 100 Hertz.
5. A system for detecting the presence of objects moving at relatively slow speeds adjacent to, and on at least one side of, a vehicle upon which the system is mounted, including:
(a) a transceiver for emitting signals along side a vehicle upon which the system is mounted and for receiving reflections of the emitted signals;
(b) a Doppler circuit, coupled to the transceiver, for generating a Doppler signal having a frequency equal to the difference between the transmitted signal and the received signal;
(c) signal processing section for:
(1) setting the gain of the Doppler signal such that only targets within a range of approximately 15 feet of the transceiver are detected;
(2) sampling the Doppler signal during periods concurrent with the emission of the emitted signals and generating a voltage level proportional to the phase difference between the emitted and received signals;
(3) removing high frequency components and signals which represent objects moving rapidly relative to the vehicle upon which the system is mounted from the sampled Doppler signal;
(4) sensing the level of the direct current offset of the signal sampled Doppler signal to determine when the system is operating within specified limits;
(5) preventing the output of the square wave generator from causing an indication that an object is present for a predefined minimum persistence period;

25.
(d) an indicator circuit, coupled to the persistence period circuit and to the signal conditioning circuit, for indicating to the operator that the system is operating within specified limits, and indicating the presence of an object which is detected for a period which is longer than the persistence period.
CA002141547A 1992-08-14 1993-08-09 Smart blind spot sensor Expired - Fee Related CA2141547C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US93007992A 1992-08-14 1992-08-14
US930,079 1992-08-14

Publications (2)

Publication Number Publication Date
CA2141547A1 CA2141547A1 (en) 1994-03-03
CA2141547C true CA2141547C (en) 1997-06-17

Family

ID=25458900

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002141547A Expired - Fee Related CA2141547C (en) 1992-08-14 1993-08-09 Smart blind spot sensor

Country Status (10)

Country Link
US (1) US5325096A (en)
EP (1) EP0655142B1 (en)
JP (1) JPH06168398A (en)
KR (1) KR100254143B1 (en)
AT (1) ATE181602T1 (en)
AU (1) AU672997B2 (en)
BR (1) BR9306886A (en)
CA (1) CA2141547C (en)
DE (1) DE69325455T2 (en)
WO (1) WO1994004941A1 (en)

Families Citing this family (174)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5638281A (en) * 1991-01-31 1997-06-10 Ail Systems, Inc. Target prediction and collision warning system
US5517196A (en) * 1992-08-14 1996-05-14 Pakett; Allan G. Smart blind spot sensor with object ranging
US6498620B2 (en) 1993-02-26 2002-12-24 Donnelly Corporation Vision system for a vehicle including an image capture device and a display system having a long focal length
US5877897A (en) 1993-02-26 1999-03-02 Donnelly Corporation Automatic rearview mirror, vehicle lighting control and vehicle interior monitoring system using a photosensor array
US6822563B2 (en) 1997-09-22 2004-11-23 Donnelly Corporation Vehicle imaging system with accessory control
US5910854A (en) 1993-02-26 1999-06-08 Donnelly Corporation Electrochromic polymeric solid films, manufacturing electrochromic devices using such solid films, and processes for making such solid films and devices
US5670935A (en) 1993-02-26 1997-09-23 Donnelly Corporation Rearview vision system for vehicle including panoramic view
IT1272045B (en) * 1993-11-09 1997-06-11 Gilardini Spa SAFETY DEVICE FOR A VEHICLE SUITABLE TO DETECT THE PRESENCE OF BODIES IN RELATIVE MOTORCYCLE IN A REGION THAT CANNOT BE VISUALLY CONTROLLED BY A DRIVER.
US5668663A (en) 1994-05-05 1997-09-16 Donnelly Corporation Electrochromic mirrors and devices
EP0699924B1 (en) * 1994-08-24 1999-10-06 Delco Electronics Corporation Vehicle obstruction discrimination system
JP3300558B2 (en) * 1994-11-10 2002-07-08 本田技研工業株式会社 Automotive multi-channel radar device
US6891563B2 (en) 1996-05-22 2005-05-10 Donnelly Corporation Vehicular vision system
US5709281A (en) * 1995-09-14 1998-01-20 Trw Inc. Method and apparatus for adjusting steering feel
JPH09222477A (en) * 1996-02-19 1997-08-26 Toyota Motor Corp On-board radar apparatus
JP3347571B2 (en) * 1996-03-12 2002-11-20 富士通株式会社 Radar equipment
US7655894B2 (en) 1996-03-25 2010-02-02 Donnelly Corporation Vehicular image sensing system
DE29617413U1 (en) * 1996-10-07 1996-11-21 Mekra Lang Gmbh & Co Kg Monitoring device for difficult or invisible zones around motor vehicles
US8294975B2 (en) 1997-08-25 2012-10-23 Donnelly Corporation Automotive rearview mirror assembly
US6172613B1 (en) 1998-02-18 2001-01-09 Donnelly Corporation Rearview mirror assembly incorporating vehicle information display
US6326613B1 (en) 1998-01-07 2001-12-04 Donnelly Corporation Vehicle interior mirror assembly adapted for containing a rain sensor
US6124886A (en) 1997-08-25 2000-09-26 Donnelly Corporation Modular rearview mirror assembly
US8288711B2 (en) 1998-01-07 2012-10-16 Donnelly Corporation Interior rearview mirror system with forwardly-viewing camera and a control
US6445287B1 (en) 2000-02-28 2002-09-03 Donnelly Corporation Tire inflation assistance monitoring system
US6115651A (en) * 1998-01-15 2000-09-05 Cruz; Diogenes J. Large vehicle blindspot monitor
US6693517B2 (en) 2000-04-21 2004-02-17 Donnelly Corporation Vehicle mirror assembly communicating wirelessly with vehicle accessories and occupants
US6477464B2 (en) 2000-03-09 2002-11-05 Donnelly Corporation Complete mirror-based global-positioning system (GPS) navigation solution
US6329925B1 (en) 1999-11-24 2001-12-11 Donnelly Corporation Rearview mirror assembly with added feature modular display
US6127965A (en) * 1998-07-23 2000-10-03 Eaton-Vorad Technologies, L.L.C. Method and apparatus for rejecting rain clutter in a radar system
KR20000004717U (en) * 1998-08-14 2000-03-15 안문휘 Reflector auto-adjustment side mirror
DE19904777B4 (en) * 1999-02-05 2005-12-15 Mekra Lang Gmbh & Co. Kg Mirrors, in particular exterior rearview mirrors for motor vehicles
US6193380B1 (en) * 1999-04-20 2001-02-27 Raymond A. Jacobs Vehicle blind spot mirror
JP2000338237A (en) * 1999-05-28 2000-12-08 Mitsubishi Electric Corp Device for monitoring circumference of vehicle
JP3513428B2 (en) * 1999-06-02 2004-03-31 三菱電機株式会社 Warning device when vehicle changes lane
US6151175A (en) * 1999-06-08 2000-11-21 Osha; Jonathan P. Tracking mirror for a tow vehicle
US6121916A (en) * 1999-07-16 2000-09-19 Eaton-Vorad Technologies, L.L.C. Method and apparatus for recognizing stationary objects with a moving side-looking radar
DE19933327C2 (en) * 1999-07-16 2001-06-21 Bayerische Motoren Werke Ag Device for indicating a lane change intention
US6236352B1 (en) * 1999-10-28 2001-05-22 Eaton-Vorad Technologies, L.L.C. Heterodyned double sideband diplex radar
WO2007053710A2 (en) 2005-11-01 2007-05-10 Donnelly Corporation Interior rearview mirror with display
AU2001243285A1 (en) 2000-03-02 2001-09-12 Donnelly Corporation Video mirror systems incorporating an accessory module
US7370983B2 (en) 2000-03-02 2008-05-13 Donnelly Corporation Interior mirror assembly with display
US7167796B2 (en) 2000-03-09 2007-01-23 Donnelly Corporation Vehicle navigation system for use with a telematics system
US6396408B2 (en) 2000-03-31 2002-05-28 Donnelly Corporation Digital electrochromic circuit with a vehicle network
AU2001284953A1 (en) 2000-08-16 2002-02-25 Raytheon Company Safe distance algorithm for adaptive cruise control
US6707419B2 (en) 2000-08-16 2004-03-16 Raytheon Company Radar transmitter circuitry and techniques
KR100767543B1 (en) 2000-08-16 2007-10-17 레이던 컴퍼니 Switched beam antenna architecture
US6489927B2 (en) 2000-08-16 2002-12-03 Raytheon Company System and technique for mounting a radar system on a vehicle
EP1873551B1 (en) * 2000-08-16 2019-03-06 Valeo Radar Systems, Inc. Automotive radar systems and techniques
US20020075138A1 (en) * 2000-08-16 2002-06-20 Van Rees H. Barteld Portable object detection system
WO2002015323A2 (en) 2000-08-16 2002-02-21 Raytheon Company Highly integrated single substrate mmw multi-beam sensor
JP2004506909A (en) 2000-08-16 2004-03-04 レイセオン・カンパニー Video amplifier for radar receiver
EP1309882B1 (en) 2000-08-16 2004-12-08 Raytheon Company Near object detection system
US6657581B1 (en) 2000-08-16 2003-12-02 Raytheon Company Automotive lane changing aid indicator
WO2002021156A2 (en) 2000-09-08 2002-03-14 Raytheon Company Path prediction system and method
DE10060288A1 (en) 2000-12-05 2002-06-13 Bosch Gmbh Robert Vehicle with at least one sensor for detection of the vehicle surroundings
US6683560B2 (en) 2000-12-29 2004-01-27 Honeywell International Inc. System and technique for enhanced radar object detection
US7581859B2 (en) 2005-09-14 2009-09-01 Donnelly Corp. Display device for exterior rearview mirror
ES2287266T3 (en) 2001-01-23 2007-12-16 Donnelly Corporation IMPROVED VEHICLE LIGHTING SYSTEM.
US7255451B2 (en) 2002-09-20 2007-08-14 Donnelly Corporation Electro-optic mirror cell
US6708100B2 (en) 2001-03-14 2004-03-16 Raytheon Company Safe distance algorithm for adaptive cruise control
DE20105791U1 (en) * 2001-04-03 2002-08-14 Mekra Lang Gmbh & Co Kg Mirror arrangement for motor vehicles
DE10125426A1 (en) * 2001-05-25 2002-11-28 Bosch Gmbh Robert Warning system for monitoring dead angle in motor vehicles, detects direction of movement of object relative to vehicle and generates alarm accordingly
DE20110339U1 (en) 2001-06-22 2002-10-24 Mekra Lang Gmbh & Co Kg Parking assistance for use in a motor vehicle
US7697027B2 (en) 2001-07-31 2010-04-13 Donnelly Corporation Vehicular video system
US6882287B2 (en) 2001-07-31 2005-04-19 Donnelly Corporation Automotive lane change aid
US7183995B2 (en) 2001-08-16 2007-02-27 Raytheon Company Antenna configurations for reduced radar complexity
US6995730B2 (en) * 2001-08-16 2006-02-07 Raytheon Company Antenna configurations for reduced radar complexity
US6970142B1 (en) 2001-08-16 2005-11-29 Raytheon Company Antenna configurations for reduced radar complexity
US6737964B2 (en) 2001-11-05 2004-05-18 Ford Global Technologies, Llc Vehicle blind spot monitoring system
US6727808B1 (en) 2001-12-14 2004-04-27 David J. Uselmann Sonic blind spot monitoring system
EP1504276B1 (en) 2002-05-03 2012-08-08 Donnelly Corporation Object detection system for vehicle
US6918674B2 (en) 2002-05-03 2005-07-19 Donnelly Corporation Vehicle rearview mirror system
DE10220569A1 (en) * 2002-05-08 2003-11-20 Valeo Schalter & Sensoren Gmbh Method for operating a vehicle environment monitoring system and environment monitoring system
WO2003105099A1 (en) 2002-06-06 2003-12-18 Donnelly Corporation Interior rearview mirror system with compass
US7329013B2 (en) 2002-06-06 2008-02-12 Donnelly Corporation Interior rearview mirror system with compass
WO2004103772A2 (en) 2003-05-19 2004-12-02 Donnelly Corporation Mirror assembly for vehicle
AU2003278863A1 (en) 2002-09-20 2004-04-08 Donnelly Corporation Mirror reflective element assembly
US7310177B2 (en) 2002-09-20 2007-12-18 Donnelly Corporation Electro-optic reflective element assembly
DE10247290B4 (en) * 2002-10-10 2013-04-18 Volkswagen Ag Method and device for monitoring dead angles of a motor vehicle
US6927677B2 (en) * 2003-03-14 2005-08-09 Darryll Anderson Blind spot detector system
US6838981B2 (en) * 2003-03-28 2005-01-04 Visteon Global Technologies, Inc. Stopped object filtering for side object detection system
US6674394B1 (en) 2003-03-28 2004-01-06 Visteon Global Technologies, Inc. Method for determining object location from side-looking sensor data
US6680689B1 (en) 2003-03-28 2004-01-20 Visteon Global Technologies, Inc. Method for determining object classification from side-looking sensor data
US7446924B2 (en) 2003-10-02 2008-11-04 Donnelly Corporation Mirror reflective element assembly including electronic component
US7308341B2 (en) 2003-10-14 2007-12-11 Donnelly Corporation Vehicle communication system
US7526103B2 (en) 2004-04-15 2009-04-28 Donnelly Corporation Imaging system for vehicle
JP3936713B2 (en) * 2004-09-24 2007-06-27 三菱電機株式会社 Rear side warning device for vehicles
US7881496B2 (en) 2004-09-30 2011-02-01 Donnelly Corporation Vision system for vehicle
US7720580B2 (en) 2004-12-23 2010-05-18 Donnelly Corporation Object detection system for vehicle
EP1883855B1 (en) 2005-05-16 2011-07-20 Donnelly Corporation Vehicle mirror assembly with indicia at reflective element
US20070088488A1 (en) * 2005-10-14 2007-04-19 Reeves Michael J Vehicle safety system
JP2007178183A (en) * 2005-12-27 2007-07-12 Mazda Motor Corp Obstacle detection device for vehicle
US7972045B2 (en) 2006-08-11 2011-07-05 Donnelly Corporation Automatic headlamp control system
US7602276B2 (en) 2007-01-17 2009-10-13 Visteon Global Technologies, Inc. Variable blind spot warning system
EP3624086A1 (en) 2007-01-25 2020-03-18 Magna Electronics Inc. Radar sensing system for vehicle
US7914187B2 (en) 2007-07-12 2011-03-29 Magna Electronics Inc. Automatic lighting system with adaptive alignment function
US8017898B2 (en) 2007-08-17 2011-09-13 Magna Electronics Inc. Vehicular imaging system in an automatic headlamp control system
WO2009036176A1 (en) 2007-09-11 2009-03-19 Magna Electronics Imaging system for vehicle
US8446470B2 (en) 2007-10-04 2013-05-21 Magna Electronics, Inc. Combined RGB and IR imaging sensor
JP5627240B2 (en) * 2008-01-16 2014-11-19 三菱電機株式会社 Dynamic obstacle judgment device
US7965197B1 (en) 2008-02-07 2011-06-21 Engelmann Eric D Vehicle blind spot occupation warning system
US20090212974A1 (en) * 2008-02-25 2009-08-27 Denso International America, Inc. Parking aid notification by vibration
US8154418B2 (en) 2008-03-31 2012-04-10 Magna Mirrors Of America, Inc. Interior rearview mirror system
US20090254260A1 (en) * 2008-04-07 2009-10-08 Axel Nix Full speed range adaptive cruise control system
US20100020170A1 (en) 2008-07-24 2010-01-28 Higgins-Luthman Michael J Vehicle Imaging System
US9487144B2 (en) 2008-10-16 2016-11-08 Magna Mirrors Of America, Inc. Interior mirror assembly with display
US9126525B2 (en) 2009-02-27 2015-09-08 Magna Electronics Inc. Alert system for vehicle
US8376595B2 (en) 2009-05-15 2013-02-19 Magna Electronics, Inc. Automatic headlamp control
US9495876B2 (en) 2009-07-27 2016-11-15 Magna Electronics Inc. Vehicular camera with on-board microcontroller
CN102481874B (en) 2009-07-27 2015-08-05 马格纳电子系统公司 Parking assistance system
EP2473871B1 (en) 2009-09-01 2015-03-11 Magna Mirrors Of America, Inc. Imaging and display system for vehicle
US8890955B2 (en) 2010-02-10 2014-11-18 Magna Mirrors Of America, Inc. Adaptable wireless vehicle vision system based on wireless communication error
DE102010012749A1 (en) * 2010-03-25 2011-09-29 Kuka Laboratories Gmbh Method for operating an autonomous industrial truck
DE102010018038B4 (en) 2010-04-23 2023-08-10 Valeo Schalter Und Sensoren Gmbh Method for warning a driver of a vehicle of the presence of objects in a blind spot area and corresponding driver assistance device
US20110291874A1 (en) * 2010-06-01 2011-12-01 De Mersseman Bernard Vehicle radar system and method for detecting objects
US9117123B2 (en) 2010-07-05 2015-08-25 Magna Electronics Inc. Vehicular rear view camera display system with lifecheck function
US8537031B2 (en) 2010-09-30 2013-09-17 Toyota Motor Engineering & Manufacturing North America, Inc. Audible blind spot indicator
WO2012068331A1 (en) 2010-11-19 2012-05-24 Magna Electronics Inc. Lane keeping system and lane centering system
WO2012075250A1 (en) 2010-12-01 2012-06-07 Magna Electronics Inc. System and method of establishing a multi-camera image using pixel remapping
US9264672B2 (en) 2010-12-22 2016-02-16 Magna Mirrors Of America, Inc. Vision display system for vehicle
US9085261B2 (en) 2011-01-26 2015-07-21 Magna Electronics Inc. Rear vision system with trailer angle detection
US9194943B2 (en) 2011-04-12 2015-11-24 Magna Electronics Inc. Step filter for estimating distance in a time-of-flight ranging system
US9547795B2 (en) 2011-04-25 2017-01-17 Magna Electronics Inc. Image processing method for detecting objects using relative motion
WO2013016409A1 (en) 2011-07-26 2013-01-31 Magna Electronics Inc. Vision system for vehicle
US20140218535A1 (en) 2011-09-21 2014-08-07 Magna Electronics Inc. Vehicle vision system using image data transmission and power supply via a coaxial cable
US9681062B2 (en) 2011-09-26 2017-06-13 Magna Electronics Inc. Vehicle camera image quality improvement in poor visibility conditions by contrast amplification
US9146898B2 (en) 2011-10-27 2015-09-29 Magna Electronics Inc. Driver assist system with algorithm switching
DE102011055693A1 (en) * 2011-11-24 2013-05-29 Hella Kgaa Hueck & Co. Radar apparatus and method for detecting a failure of a receiving channel of a radar device
WO2013081985A1 (en) 2011-11-28 2013-06-06 Magna Electronics, Inc. Vision system for vehicle
GB2498568B (en) 2012-01-20 2014-09-24 Cp Electronics Ltd Sensing device and method of calibration
US8694224B2 (en) 2012-03-01 2014-04-08 Magna Electronics Inc. Vehicle yaw rate correction
US10609335B2 (en) 2012-03-23 2020-03-31 Magna Electronics Inc. Vehicle vision system with accelerated object confirmation
WO2013158592A2 (en) 2012-04-16 2013-10-24 Magna Electronics, Inc. Vehicle vision system with reduced image color data processing by use of dithering
US10089537B2 (en) 2012-05-18 2018-10-02 Magna Electronics Inc. Vehicle vision system with front and rear camera integration
US9340227B2 (en) 2012-08-14 2016-05-17 Magna Electronics Inc. Vehicle lane keep assist system
DE102013217430A1 (en) 2012-09-04 2014-03-06 Magna Electronics, Inc. Driver assistance system for a motor vehicle
US9558409B2 (en) 2012-09-26 2017-01-31 Magna Electronics Inc. Vehicle vision system with trailer angle detection
US9446713B2 (en) 2012-09-26 2016-09-20 Magna Electronics Inc. Trailer angle detection system
US9743002B2 (en) 2012-11-19 2017-08-22 Magna Electronics Inc. Vehicle vision system with enhanced display functions
US9090234B2 (en) 2012-11-19 2015-07-28 Magna Electronics Inc. Braking control system for vehicle
US10025994B2 (en) 2012-12-04 2018-07-17 Magna Electronics Inc. Vehicle vision system utilizing corner detection
US9481301B2 (en) 2012-12-05 2016-11-01 Magna Electronics Inc. Vehicle vision system utilizing camera synchronization
WO2014107490A2 (en) * 2013-01-01 2014-07-10 Sharghi Shahriar Mokhtari Sytstems for indicating visibility of a blind spot to a driver
US9092986B2 (en) 2013-02-04 2015-07-28 Magna Electronics Inc. Vehicular vision system
US20140218529A1 (en) 2013-02-04 2014-08-07 Magna Electronics Inc. Vehicle data recording system
US10027930B2 (en) 2013-03-29 2018-07-17 Magna Electronics Inc. Spectral filtering for vehicular driver assistance systems
US9327693B2 (en) 2013-04-10 2016-05-03 Magna Electronics Inc. Rear collision avoidance system for vehicle
US10232797B2 (en) 2013-04-29 2019-03-19 Magna Electronics Inc. Rear vision system for vehicle with dual purpose signal lines
US9508014B2 (en) 2013-05-06 2016-11-29 Magna Electronics Inc. Vehicular multi-camera vision system
US10567705B2 (en) 2013-06-10 2020-02-18 Magna Electronics Inc. Coaxial cable with bidirectional data transmission
US9260095B2 (en) 2013-06-19 2016-02-16 Magna Electronics Inc. Vehicle vision system with collision mitigation
US20140375476A1 (en) 2013-06-24 2014-12-25 Magna Electronics Inc. Vehicle alert system
US10326969B2 (en) 2013-08-12 2019-06-18 Magna Electronics Inc. Vehicle vision system with reduction of temporal noise in images
KR101815721B1 (en) 2013-10-07 2018-01-08 주식회사 만도 Apparatuses and Methods for warning blind spot
US9988047B2 (en) 2013-12-12 2018-06-05 Magna Electronics Inc. Vehicle control system with traffic driving control
JP6413240B2 (en) 2014-01-08 2018-10-31 株式会社デンソー Vehicle control device and vehicle
US10160382B2 (en) 2014-02-04 2018-12-25 Magna Electronics Inc. Trailer backup assist system
EP2913239B1 (en) * 2014-02-28 2019-06-19 Volvo Car Corporation Method and unit for managing following space
US9623878B2 (en) 2014-04-02 2017-04-18 Magna Electronics Inc. Personalized driver assistance system for vehicle
JP6323256B2 (en) 2014-08-27 2018-05-16 株式会社デンソー Detection device
US10399495B1 (en) * 2014-09-05 2019-09-03 United Services Automobile Association (Usaa) Systems and methods for indicating proximity conditions for a vehicle
US9392358B2 (en) 2014-10-28 2016-07-12 Robert Bosch Gmbh Waveguide for shaping sound waves
US10366285B2 (en) 2015-04-09 2019-07-30 Bendix Commercial Vehicle Systems Llc Method and apparatus for determining the operation of a vehicle safety system
US10819943B2 (en) 2015-05-07 2020-10-27 Magna Electronics Inc. Vehicle vision system with incident recording function
US10078789B2 (en) 2015-07-17 2018-09-18 Magna Electronics Inc. Vehicle parking assist system with vision-based parking space detection
US10086870B2 (en) 2015-08-18 2018-10-02 Magna Electronics Inc. Trailer parking assist system for vehicle
US10875403B2 (en) 2015-10-27 2020-12-29 Magna Electronics Inc. Vehicle vision system with enhanced night vision
US11277558B2 (en) 2016-02-01 2022-03-15 Magna Electronics Inc. Vehicle vision system with master-slave camera configuration
US11433809B2 (en) 2016-02-02 2022-09-06 Magna Electronics Inc. Vehicle vision system with smart camera video output
US10132971B2 (en) 2016-03-04 2018-11-20 Magna Electronics Inc. Vehicle camera with multiple spectral filters
US10055651B2 (en) 2016-03-08 2018-08-21 Magna Electronics Inc. Vehicle vision system with enhanced lane tracking
US10421399B2 (en) * 2017-05-26 2019-09-24 GM Global Technology Operations LLC Driver alert systems and methods based on the presence of cyclists
DE102019216584A1 (en) * 2019-10-28 2021-04-29 Continental Automotive Gmbh Self-propelled agricultural machine and method for assisting a driver of a self-propelled agricultural machine in driving the agricultural machine
US20220392334A1 (en) * 2019-11-11 2022-12-08 Jcftechnology Co., Ltd. Security surveillance microwave sensor having reduced false report rate by means of biological signal detection
US11968639B2 (en) 2020-11-11 2024-04-23 Magna Electronics Inc. Vehicular control system with synchronized communication between control units

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2071418A5 (en) * 1969-12-29 1971-09-17 Dessailly Rene
US3778826A (en) * 1969-12-30 1973-12-11 Pierson M Anti-collision vehicular radar system
US3697985A (en) * 1970-09-23 1972-10-10 Bendix Corp Rear end warning system for automobiles
US3760415A (en) * 1971-12-23 1973-09-18 Department Of Transportation Microwave crash sensor for automobiles
US3859660A (en) * 1972-02-14 1975-01-07 Midwest Microwave Inc Doppler radar for land vehicles
US3750169A (en) * 1972-03-13 1973-07-31 Sperry Rand Corp Vehicular safety system
US3898652A (en) * 1973-12-26 1975-08-05 Rashid Mary D Vehicle safety and protection system
US3978481A (en) * 1974-06-17 1976-08-31 Merlin A. Pierson Anti-collision vehicular radar system
JPS5269131A (en) * 1975-12-02 1977-06-08 Nissan Motor Co Ltd Collision preventing and warning apparatus
JPS5618774A (en) * 1979-07-24 1981-02-21 Honda Motor Co Ltd Radar apparatus for automobile
JPH0685484B2 (en) * 1985-06-29 1994-10-26 日本電装株式会社 Antenna device
DE3730105A1 (en) * 1987-09-08 1989-03-16 Pietzsch Ibp Gmbh METHOD AND DEVICE FOR SECURING A VEHICLE OR DEVICE MOVING IN SPACE
DE3902852A1 (en) * 1989-02-01 1990-08-02 Hohe Kg EXTERIOR MIRROR FOR A MOTOR VEHICLE
US5008678A (en) * 1990-03-02 1991-04-16 Hughes Aircraft Company Electronically scanning vehicle radar sensor
US5087918A (en) * 1990-04-02 1992-02-11 Delco Electronics Corporation FMCW/2FD implementation for vehicle near obstacle detection system
US5115245A (en) * 1990-09-04 1992-05-19 Hughes Aircraft Company Single substrate microwave radar transceiver including flip-chip integrated circuits
US5181038A (en) * 1991-05-06 1993-01-19 Ivhs Technologies, Inc. Target persistence filter for multi-frequency automotive radar system

Also Published As

Publication number Publication date
AU672997B2 (en) 1996-10-24
JPH06168398A (en) 1994-06-14
US5325096A (en) 1994-06-28
DE69325455T2 (en) 2000-03-30
CA2141547A1 (en) 1994-03-03
EP0655142B1 (en) 1999-06-23
DE69325455D1 (en) 1999-07-29
EP0655142A1 (en) 1995-05-31
ATE181602T1 (en) 1999-07-15
KR950703158A (en) 1995-08-23
AU4805693A (en) 1994-03-15
EP0655142A4 (en) 1995-12-20
KR100254143B1 (en) 2000-04-15
WO1994004941A1 (en) 1994-03-03
BR9306886A (en) 1998-12-08

Similar Documents

Publication Publication Date Title
CA2141547C (en) Smart blind spot sensor
US5517196A (en) Smart blind spot sensor with object ranging
US5028920A (en) Driver alerting device
US4803488A (en) Driver alerting device
US4864298A (en) Driver alerting device
US5754123A (en) Hybrid ultrasonic and radar based backup aid
US5572484A (en) Short range ultrasonic distance warning system for motor vehicle
US6069581A (en) High performance vehicle radar system
US5734336A (en) Collision avoidance system
US6400308B1 (en) High performance vehicle radar system
US5087918A (en) FMCW/2FD implementation for vehicle near obstacle detection system
US6222457B1 (en) Electronic trailer hitching system
US5760708A (en) Signaling means
US7385486B2 (en) Device for detecting moving objects
KR20010041181A (en) High performance vehicle radar system
US5432516A (en) Radar obstacle detection system with self test
US20080001809A1 (en) Detecting signal interference in a vehicle system
US20070182587A1 (en) Method and device for detecting objects in the surroundings of a vehicle
KR20000011892A (en) Method and apparatus for rejecting rain clutter in a radar system
EP1057046A2 (en) High performance vehicle radar system
US4667195A (en) Rear monitor system triggered by occupant leaving the vehicle
AU620339B2 (en) Driver alerting device
US6832137B2 (en) Leaky cable based method and system for automotive parking aid, reversing aid, and pre-collision sensing
WO1998019177A1 (en) Method and apparatus for detection of objects proximate to an automotive vehicle
CA1249871A (en) Vehicle backing-up alert

Legal Events

Date Code Title Description
EEER Examination request
MKLA Lapsed