Automotive radars have come a long way since first use in cars. OEMs are finding newer applications for Radar both inside and outside the car. Inside being identifying live objects in the car, which is a regulatory driven application. Outside of the car for numerous ADAS and AD applications. Read more about basic radar system
here
Advantage of using radar for ADAS application:
It is known that radar works on theprinciple of transmitting and receiving radio waves after reflection. While other sensors such as camera, LiDAR, ultrasonic systems are inprevalence, Radar based systems have some inherent advantages such as:
- Radar is touted to be an all-weather solution. Real world working conditions such as temperature, humidity etc. do not affect the functioning of radar-based systems. One of the key advantages of radar is that it works seamlessly under varying lighting conditions – night or day.
- Long Range Radar (LRR) systems can see really far – LRR can comfortably handle between 30 to 250 meters range.
- Materials that are generally considered as insulators such as rubber do not affect radar-based systems.
- It is relatively easier to accurately measure velocity, distance and exactposition of the object using radio waves.
- Radar can easily differentiate between stationary and moving objects which is one of the major shortcomings ofproximity sensor-based systems.
- Radar can detect multiple objects simultaneously which cannot be done inproximity based sensors.
- When used in conjunction with existing camera- based systems, 3D images can be created by use of radar by means of angle detection of the object and sensor fusion with existing camera-based data.
Some of the key challenges in radar based system
With regulationsput forth for ADAS and other must-have safety applications by regulatory bodies, this decade is all set to see newer applications for radar, as well as drastic improvements.
Automotive Radar in current form face issues with respect topackaging, interference with other radar sensors as well as radar sensors from neighbouring cars, styling, compatibility with the car design, installation, calibration and testing.
Trends:
Some of the trends that one can foresee in radar would be :
- Use of common and agreed bandwidth of all automotive applications
- Vehicle integration orpackaging
- Cost effective sensors thanks to the use of common bandwidth
Down the line application for radar
- Rear cross traffic aler>
- Surround view
- Autonomous emergency braking
MMIC radar
MMIC chipsets use microwave frequency to transmit the information on the objects ahead. They are deployed depending on the area to be covered. MMIC radars are used at both ends of the spectrum, at 24GHz they are used in applications such as blind spot detection, lane change assist, at 77GHz applications such as emergency braking, automatic cruise control.
Imaging Radar
Unlike Lidar or MMIC radar, imaging radars are used majorly in long range applications thanks to its ability to detect distance, relative velocity as well as height- angular measurement in a spherical coordinate system (Azimuth). Imaging radars uses MIMO antenna array to map the surrounding area.
Conclusion
Radar systems have a wide range of applications, adoption of radar haspaved the way for improving accuracy of ADAS applications. Radar is not only economical compared to other technology but alsoprovides a wider range of applications. It is aproven technology and with advances in customized software algorithms, it is fast becoming one of the most viable options for car manufacturers and OEMs who foresee ADAS and autonomous driving as the future of mobility.
Further reading
- Here is a real-life case study of how we optimized radar based object detection system for an automotive tier-1
- FMCW CHIRP configurations for SRR, MRR and LRR
