Title:
SYSTEM AND METHOD FOR DISTINGUISHING BETWEEN ACTIVE AND PASSIVE NFC DEVICES BASED ON ADJUSTMENT OF CARRIER FREQUENCY
Document Type and Number:
WIPO Patent Application WO/2022/133717
Kind Code:
A1
Abstract:
A near field communication (NFC) reader detects whether NFC devices are passive NFC devices or active NFC devices. The NFC reader outputs an interrogation signal and a carrier signal. When the NFC reader receives a response signal from an NFC device responsive to the interrogation signal, the NFC reader adjusts the frequency of the carrier signal before the end of the response signal. The NFC reader determines whether the NFC device is a passive NFC device or an active NFC device based on characteristics of the remaining portion of the response signal.
Inventors:
XIONG TIANHAO (CN)
WU GANG (CN)
WU GANG (CN)
Application Number:
PCT/CN2020/138274
Publication Date:
June 30, 2022
Filing Date:
December 22, 2020
Export Citation:
Assignee:
STMICROELECTRONICS CHINA INVEST CO LTD (CN)
International Classes:
H04B5/00
Foreign References:
| US20140353390A1 | 2014-12-04 | |||
| US20200151403A1 | 2020-05-14 | |||
| US10192373B1 | 2019-01-29 | |||
| CN107925443A | 2018-04-17 |
Attorney, Agent or Firm:
KING & WOOD MALLESONS (CN)
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