Patent ID: 8365310
Filing Date: 2013-01-29
Classification: G06K,H04L

Abstract:
1. A method of protecting an RFID tag from power analysis or from cryptanalytic attacks based on power analysis, such as SPA and DPA, said RFID tag including a power extraction circuit and a computational circuit, comprising the steps of extracting power from an electromagnetic or magnetic field generated by a reader in whose proximity the tag is located, modifying the power extraction circuit of the RFID tag by providing at least two capacitors configured relative to the power extraction circuit to double-buffer the extracted power during normal functioning of the RFID tag by so that at any stage in time, except possibly during changeover periods, at least one capacitor is being charged by the extracted power while at least one other capacitor is uncoupled from the power extraction circuit and is being discharged to power the computational circuit of the RFID tag, and continuously switching the capacitors so that the discharged capacitor is connected to be charged by the extracted power and the charged one is uncoupled from the power extraction circuit.