The LEGO Radar System (LRS) is based on reflection of ultrasonic waves and infrared light and is technically not seen as a radar, which operates based on reflection of electromagnetic waves.
In its operations the LRS scans an area of 160 degree at a range of m. For in-house operation this is regarded as sufficient, however the range can be increased up to the max of the Ultrasonic Sensor at m. The LRS uses a combination of ultrasonic and infrared light reflection to deliver best results on a wide range of surfaces, including walls, carpets, curtains, windows …
A program download is available at:
The LRS is built with LEGO bricks and programed with the LEGO MINDSTORMS EV3 Software, with the exception of the cables, which are from Mindsensors due to their higher flexibility.