Both safety and security technologies for autonomous driving have evolved in the past years, nowadays active and predictive systems are being implemented on a large scale across the automotive industry. As no single technology is sufficient to meet all the stringent regulations for self-driving vehicles, a mix of advanced innovations are equipping cars and trucks to avoid accidents and provide security, comfort, and efficiency to drivers, passengers, pedestrians, and also other drivers.
The raising concerns about safety and security together with the shift towards self-driving vehicles are surging the automotive radar market growth (it will reach almost US$5 billion by 2026, according to Transparency Market Research). Radar-based embedded technologies have become an essential component of Advanced Driver Assistance Systems (ADAS) as they can sense the distance between vehicles in real-time and improve driving safety and security. Radar systems detect, warn, and mitigate collisions —or avoid them when possible. They also monitor and catch blind spots that are used for Rear Cross Traffic Alert (RCTA), Lane Departure Warning (LDW) and Lane Keeping Assist (LKA), and Pedestrian Detection systems.
A typical radar module consists in a transmitter (Tx) with a voltage-controlled oscillator (VCO) connected to an MCU and a local oscillator (LO) signal for sending out radio waves through steerable antennas; those radio waves hit an object and bounce back to a three-channel receiver IC (Rx). The radar module detects distance, speed, and direction of the object by controlling the orientation of the sent-received radio waves.
Automotive radars technologies can be categorized into three buckets:
- Short-range radars: used for sensing proximity. Requiring a steerable antenna with a large scanning angle, creating wide scanning ranges.
- Medium-range radars: used for detecting objects within broader scanning ranges.
- Long-range radars: used for measuring distance and speed. Requiring a high-resolution directive antennas with limited scanning ranges.
The democratization of radar systems is taking advantage of the cost cuts manufacturers are making to their new speeded-up silicon chips, ditching the traditional compound semiconductors. These new technologies are allowing automotive engineers to reduce the size of the implemented radar systems, following the standardization of frequency allocation (moving from 24GHz to 77GHz) across the globe and uniforming the bands to get higher resolution benefits and reducing the risk of interference.
As the performance bar for RADAR applications has been raised (demanding precise object detection and classification, accurate velocity resolution, and improved spatial resolution), it is essential to promote the democratization of radar systems to achieve complete vehicle autonomy, all together with developing vision, ultrasonic, and Light Detection and Ranging (LIDAR) technologies.