Patent attributes
A radar system for an autonomous driving vehicle (ADV) is disclosed. The system includes a target that includes a number of target elements disposed in a predetermined configuration on the target to collectively represent a radar readable code. The system further includes a radar unit included in the ADV and configured to: transmit a first electromagnetic (EM) signal to the target within a driving environment, receive a second EM signal reflected by the target, compute a radar cross section (RCS) signature based on the received second EM signal, generate a corresponding communication message based on the computed RCS signature, and transmit radar data that includes the communication message, where the ADV is controlled based on the communication message.