Stmicroelectronics Austria Gmbh

Thomas Poetscher

Gustavo Jose Henriques Patricio

Oliver Regenfelder

Michael Gugganig

Ulrich Herrmann

In an embodiment a device includes an electrically conductive structure, a near field communication (NFC) reader including a support supporting an electrically conductive NFC loop antenna system located in a vicinity of the electrically conductive structure and a component configured to excite the loop antenna system with a current, wherein the loop antenna system has a geometry configured to generate several electromagnetic fields in response to excitation by the current, the electromagnetic fields having a NFC carrier frequency and respective different field directions adapted to induce respective eddy currents cancelling each other in the electrically conductive structure.

NFC loop antenna in the vicinity of a metallic structure, and method for operating this antenna

In an embodiment, a method of managing an output power delivered by an antenna of a NFC apparatus includes: providing a matching circuit with a first tuning capacitive network coupled in series between a NFC controller and the antenna and with a second tuning capacitive network coupled to the NFC controller and the antenna and to a reference terminal, wherein the first or second tuning capacitive network has a variable capacitive value; determining tuning capacitive values of the first tuning capacitive networks to adjust a delivered output power at a desired level; and setting the tuning capacitive values of the first tuning capacitive network to the tuning capacitive values.

Method of managing an output power delivered by an antenna of a NFC apparatus and NFC apparatus

An embodiment method comprises transmitting a reader carrier signal from a contactless reader to a contactless device, receiving by the reader, a device modulated carrier signal from the device, the device modulated carrier signal having a carrier frequency, preferably turning off by the reader, the transmission of the reader carrier signal during reception of the device modulated carrier signal, and after having turned off the transmission of the reader carrier signal, determining by the reader the presence or the absence at the reader's antenna of a modulated carrier signal having at the reader's antenna the carrier frequency with a tolerance, without relying on the data content of the modulated carrier signal.

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Deutschfeistritz, Austria

Thomas Poetscher