Car-to-car communication based on modulated active backscatter and automotive radar

This work proposes a method of communicating between two vehicles using an onboard FMCW radar and a modulated backscatter tag. The system allows real-time detection and classification of signals, such as stop signals, turn signals, or emergency lights, without adding other communication systems. A proof-of-concept prototype has been designed at 24 GHz. The tag consists of a MMIC amplifier connected between the receiving and transmitting antennas. The modulation is performed by switching the power supply of the amplifier. The classification information is encoded in the switching rate used and the tag is detected using conventional range-Doppler map. The tag is installed on the rear of the car and responds by modulating the backscatter field when illuminated by the radar. Experimental results and outdoors test will be given to show the feasibility of the proposed solution.