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Far Distance Sensors (FDS). Bryan Guzman. ECE 5320 Mechatronics. Assignment #1. What is a FDS? Today’s Application Characteristics Advantages and Disadvantages Types of FDS Future Applications. Far Distance Sensors (FDS). Reference List:.
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Far Distance Sensors (FDS) Bryan Guzman ECE 5320 Mechatronics Assignment #1
What is a FDS? Today’s Application Characteristics Advantages and Disadvantages Types of FDS Future Applications Far Distance Sensors (FDS)
Reference List: • Hermann Rohling, et al: Multistatic Radar Principles for Automotive RadarNet Applications. 2002 • Adrian Garrod: Automotive Radar Geared up for Future Motoring.2003 • Rick Nelson: Radar gives cars eyes. Test & Measurement World. 2002 • Mainz: European Ultra Wide Band Workshop, BOSCH. 2003
What is a FDS? A FDS is a Smart Radar Sensor used to measure range and relative speed with extremely high accuracy. These type of sensors are used today for automotive collision avoidance systems. FDS sensors are mounted in front of the car to provide target position relative to the vehicle and can measure up to 180 m.
Today’s Application: • Far distanceradar sensors are used today in adaptive-cruise control (ACC) systems for safety standards in passenger vehicles to provide: - Collision warning information - Urban collision avoidance - Stop and go. - Parking Aid.
FDS Characteristhics: • Maximum range of 180 meters. • High resolution and accuracy forTarget range, velocity and azimuth angle measurements. • Frequency of 76- to 77-GHz. “Table 1: Typical ACC system [Roh95]. SIEMENS VDO”
“Figure 1. Rohling: Typical ACC system [Roh95]. SIEMENS VDO”
Advantages: • Very precise and high accuracy in range and relative speed measurements at far distances. • Large range (up to 180 m) measurement. • Small moderate antenna size inside vehicle bumper . • Doesn’t disturb the appearance of the vehicle. • Interference avoidance between adjacent radar sensors.
Disadvantages: • Cost is too high. • Unacceptable attenuation of Microwave propagation through bumper material. • FDS are still being tested on new ACC systems. • Not useful for dense traffic. If the radar wave is reflected by more than one vehicle, the radar signal delivers no information, which makes unambiguous assignment of the measured speed to a single vehicle possible.
Example of a Car with distance radar sensors placed on front end: “Rohling: Typical ACC system [Roh95]. SIEMENS VDO”
FDS Key Measurements: • Distance to the target, determined by the time delay between radar signal transmission and reception or the phase difference between multiple transmitted frequencies, • Target speed, determined by the Doppler frequency shift of the returned signal, • Target size (bicycle or truck), determined by relative power of the returned signal, and • Target angle, typically within a range ±12°, determined by switching the DUT antenna between multiple fixed beams, mechanically scanning a narrow beam, or using monopulse receive techniques.
Types of FD radar sensor: • Monostatic, which transmit and recieves. • Bistatic, which has two stations (transminiting and receiving stations) • Multistatic, has more than one revieving station.
“Rohling: Multistatic Radar Principles for Automotive RadarNet Applications”
Future Applications: Far distance radar sensors are currently under development for various applications to increase safety standard in cars of tomorrow, giving drivers visual and audio collision warnings. These type of sensors are already being applied by car companies such as Honda, BMW, etc.