US Patent 11126905 Antenna-less RFID tag

A semi-passive radio frequency identification (RFID) tag includes a digital circuit with switching components operating within an interrogation range of an incident carrier wave. A plurality of input connections and output connections direct data communications through the switching components within the digital circuit, and the data communications are subject to switching operations of the switching components between at least one of the input connections and at least one of the output connections. A backscatter response reflected from the digital circuit upon arrival of the incident carrier wave, wherein the backscatter response is a modulated backscatter response in the presence of the switching operations.