Measurement of radar cross section for passive UHF RFID tags

In this paper, we first describe the functionality of a passive UHF RFID system for which down link (tag to the reader) is based on amplitude shift keying (ASK). We show that modulating the load chip, will also modulate the radar cross section of the tag and so change the backscattered power. The research work is based on analytical formulation, simulation results and backscattering power measurement. Theoretical results are found to be in good agreement with simulation results and experimental data. (6 pages)