A system comprising a first device and a second device the second device, located on a host vehicle, wherein the first device comprises: at least one antenna (52, 54); a receiver in signal communication with the at least one antenna; a passive radio frequency identification, RFID, device in signal communication with the at least one antenna, the passive RFID device configured to provide a return signal comprising RFID identification information via the at least one antenna in response to receiving a read pulse via the at least one antenna; a processor; and an output device; wherein the second device comprises: a transceiver (32, 34); and a processor coupled to the transceiver and configured to transmit a radar signal that includes the read pulse via the transceiver, wherein the processor is further configured to: receive the return signal from the passive RFID device, determine, based on a plurality of received return signals, a track of the first device, determine, based on the track of the first device, whether the first device and the second device are on a collision course, and send a warning signal to the first device in response to determining that the first device and the second device are on the collision course, the warning signal comprising warning identification information; wherein the processor of the first device is configured to: receive the warning signal from the second device via the receiver, determine whether the warning identification information in the warning signal matches the RFID identification information to determine if the warning signal is for the first device, and generate an alert signal in response to determining that the warning identification information matches the RFID identification information, the output device being configured to provide an alert based on the generated alert signal. at least one antenna (52, 54); a receiver in signal communication with the at least one antenna; a passive radio frequency identification, RFID, device in signal communication with the at least one antenna, the passive RFID device configured to provide a return signal comprising RFID identification information via the at least one antenna in response to receiving a read pulse via the at least one antenna; a processor; and an output device; a transceiver (32, 34); and a processor coupled to the transceiver and configured to transmit a radar signal that includes the read pulse via the transceiver, wherein the processor is further configured to: receive the return signal from the passive RFID device, determine, based on a plurality of received return signals, a track of the first device, determine, based on the track of the first device, whether the first device and the second device are on a collision course, and send a warning signal to the first device in response to determining that the first device and the second device are on the collision course, the warning receive the return signal from the passive RFID device, determine, based on a plurality of received return signals, a track of the first device, determine, based on the track of the first device, whether the first device and the second device are on a collision course, and send a warning signal to the first device in response to determining that the first device and the second device are on the collision course, the warning signal comprising warning identification information; receive the warning signal from the second device via the receiver, determine whether the warning identification information in the warning signal matches the RFID identification information to determine if the warning signal is for the first device, and generate an alert signal in response to determining that the warning identification information matches the RFID identification information, the output device being configured to provide an alert based on the generated alert signal.