公开(公告)号：US20190020467A1

公开(公告)日：2019-01-17

申请号：US16029457

申请日：2018-07-06

Applicant: STMICROELECTRONICS SA ,  STMicroelectronics Razvoj Polprevodnikov d.o.o.

Inventor： Maksimiljan STIGLIC ,  Nejc SUHADOLNIK ,  Marc HOUDEBINE

IPC: H04L7/033 ,  H04B5/00 ,  G06K19/07 ,  H03L7/099 ,  H03C3/09

Abstract: A transponder communicates with a reader using active load modulation. The transponder includes a digital phase locked loop (DPLL), which, in operation, generates an active load modulation (ALM) carrier clock synchronized to carrier clock of the reader. Between transmission of data frames, the DPLL is placed in a lock mode of operation in which a feedback loop of the DPLL is closed. Within a transmitted data frame having a duration, the DPLL is placed, for the duration of the transmitted data frame, in a hold mode of operation in which the feedback loop is opened. A phase of the ALM carrier clock is adjusted at least once during the duration of the transmitted data frame.

公开(公告)号：US20170146578A1

公开(公告)日：2017-05-25

申请号：US15139801

申请日：2016-04-27

Applicant: STMICROELECTRONICS SA

Inventor： Marc HOUDEBINE ,  Sebastien Dedieu

IPC: G01R23/10

CPC classification number: G01R23/10 ,  G01R23/02 ,  H03D13/001

Abstract: A method includes a) counting whole periods of a signal during a first period of a reference signal, b) repeating step a) for each period of the reference signal until a first duration is equal to a first quantity of periods of the reference signal, and c) determining a first average of the whole periods. The method also includes repeating at least one of steps a) to c) and at each repetition shifting a start of the counting of step a) by at least one period of the reference signal, and in steps b) and c) accounting for whole periods of the signal already counted during the at least one preceding group of steps a) and b). The method includes determining a second average of the first averages, and determining the frequency of the signal from the second average and the frequency of the reference signal.