公开(公告)号：US20210374365A1

公开(公告)日：2021-12-02

申请号：US17332405

申请日：2021-05-27

Applicant: STMicroelectronics Austria GmbH

Inventor： Gustavo Jose Henriques Patricio ,  Oliver Regenfelder ,  Ulrich Herrmann ,  Thomas Poetscher

IPC: G06K7/10 ,  H04B5/00 ,  G06K19/07

Abstract: 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.

公开(公告)号：US11416692B2

公开(公告)日：2022-08-16

申请号：US17332405

申请日：2021-05-27

Applicant: STMicroelectronics Austria GmbH

Inventor： Gustavo Jose Henriques Patricio ,  Oliver Regenfelder ,  Ulrich Herrmann ,  Thomas Poetscher

IPC: G06K7/10 ,  G06K19/07 ,  H04B5/00

Abstract: 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.