Car2Car Communication Using a Modulated Backscatter and Automotive FMCW Radar

Abstract

This work proposes the use of a modulated tag for direct communication between two vehicles using as a carrier the wave emitted by an FMCW radar installed in the vehicle for advanced driver assistance. The system allows for real-time signals detection and classification, such as stop signal, turn signals and emergency lights, adding redundancy to computer video sensors and without incorporating additional communication systems. A proof-of-concept tag has been designed at the microwave frequency of 24 GHz, consisting of an amplifier connected between receiving and transmitting antennas. The modulation is performed by switching the power supply of the amplifier. The tag is installed on the rear of the car and it answers when it is illuminated by the radar by modulating the backscattered field. The information is encoded in the modulation switching rate used. Simulated and experimental results are given showing the feasibility of the proposed solution.

Spoofing Attacks on FMCW Radars with Low-Cost Backscatter Tags

“…The spoofing device was based on an updated version of the backscatter tag presented in [ 59 , 60 ]. The GaAs amplifier was replaced by a pair of lower-power-consumption amplifiers, and the patch array was replaced by a lens antenna.…”

OmniScatter

“…Backscatter Communication. Multiple literature have introduced backscatter to establish an extremely energy-efficient wireless communication links [12,21,30,31,33,45,51,60,61,72,73,77,78], where [57,62] serve good overviews of recent successes. Meanwhile, papers [24,29] deployed backscatter tags to enable crosstechnology communication.…”

“…To tackle this, latest mmWave backscatter systems adopt FMCW radars -by leveraging chirp, FMCW boosts the reflected signal power in proportion to the wide mmWave bandwidth. For instance, Millimetro [52] localizes mmWave backscatters from 100m outdoors while another work [33] communicates from car to car using mmWave backscatter at 18m distance outdoors, where they use FMCW radar as a mmWave tag reader. However, such systems are designed for specific deployment scenarios, e.g., roadside for autonomous driving [52] and achieving robustness for practicality under everyday environment still remains a challenge due to the vast amount of ambient reflections (i.e., clutter noise).…”

Millimeter-Wave Multi-Channel Backscatter Communication and Ranging with an FMCW Radar

“…The FMCW radar-communication system has been studied [ 12 , 13 , 14 , 15 ]. In paper [ 12 ], a switch is used in the tag to modulate the on-off keying (OOK) signal to the FMCW.…”

“…In addition, it demonstrates that the FMCW ranging approach can be integrated with a simultaneous data transmission with a data rate of 37.5 Mbps in lab measurements. Paper [ 15 ] demonstrates the FMCW radar-communication system in a real working scenario of car-to-car communication at 24 GHz.…”