The birth of RFID technology is credited to the 1948 research paper by H. Stockman on "Communication by Means of Re?ected Power" 109]. After describing the main principle of communication by re?ection and reporting his experiments, he concluded that "Evidently, considerable research and development work has to be done before the remaining basic problems in re?ected-power com- nication are solved, and before the ?eld of useful applications is - plored...