TEST, SAFETY & SYSTEMS
RADAR READY
Testing millimetre-wave automotive radar for ADAS and autonomous driving
A Table 1
utomotive millimetre- wave radar is used to detect people and objects in Advanced
Driver Assistance Systems (ADAS) and Autonomous Driving (AD) applications. Typically, sensors to monitor the environment outside the vehicle include radar, cameras and Light Detection And Ranging (LiDAR). ADAS assists the driver in a wide range of driving operations, such as collision warning, automatic braking and parking assist. In autonomous driving, the sensor data is used to control the vehicle automatically.
Automotive radar typically operates
in the 24 and 76GHz bands. The 24GHz band is used for short and middle-range perimeter monitoring for pre-crash and collision damage reduction, as well as front and rear monitoring. Due to its high resolution, 76-77GHz radar is used primarily to detect obstacles 100 to 200 metres ahead of the vehicle. Radar is also used for interior or ‘in-cabin’ sensing applications. For example, systems that prevent children or animals from being left in cars operate in the 60-77GHz bands. Table 1 shows the automotive radar frequency allocations used in each region.
RADAR METHODS Automotive radar measurements use either the pulse or Frequency- Modulated Continuous Wave (FMCW) method. The pulse method measures the round-trip time the radio wave takes from the transceiver to the object and its refl ection to come back. The FMCW method transmits
periodic radio signals with an increased frequency in a certain period to an object. Here, the transmitted and refl ected radio waves interfere to generate a beat signal. By analysing the diff erence in frequency and other factors obtained from the
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