Patent ID: 8922347

Claim:
An extended range passive RFID transponder with an R.F. energy collection circuit, comprising: a first narrow conductance band antenna forming an interrogator receive antenna and in electrical communication with the gate electrode of a transistor switch, wherein the first narrow conductance band antenna comprises a folded dipole that is resonant at a frequency or frequencies that match the frequency or frequencies of an interrogator signal for the RFID transponder, providing −30 dB or better signal isolation from RF frequencies that do not match the frequency or frequencies of the interrogator signal, an ID transmission circuit; an R.F. energy collection circuit, comprising: a low-loss R.F. front end including a folded dipole antenna tuned to minimize lost power in two or more R.F. bands commonly used for communications for passing substantially coherent R.F. signals received therefrom; wherein the low-loss R.F. front end comprises low-resistivity alloys or noble metals embedded in a composite material having an effective permittivity that varies 5×10 −2 ° C. −1 ; a rectifier circuit coupled to receive coherent R.F. energy from the front end; and an energy storage circuit coupled to receive energy from the rectifier circuit and coupled to provide energy to the ID transmission circuit in response to an interrogation signal received by the first narrow conductance band antenna.