Array Antenna System and Algorithm Applicable to RFID Readers

Embodiments of the invention pertain to Radio Frequency Identification (RFID) method and system using an antenna array, an array controller, and control algorithms. Embodiments of the invention can induce strong radio-frequency (RF) excitation, for a given level of radiated RF power, at any point within an arbitrary inhomogeneous medium. For RFID applications, one typical inhomogeneous medium is an ensemble of cases on a pallet. Another typical medium is a warehouse environment having stored goods together with shelving and other material present. An embodiment of the invention is applicable to the process of reading battery-less, or “passive” RFID tags, which rely on incident RF electromagnetic fields established by RFID readers to power the electronic circuitry within the tags.