Systems and methods for inductively coupled communications

Patent metadata

Field	Value
Publication number	US-2016142113-A1
Application number	US-201414547837-A
Country	US
Kind code	A1
Filing date	Nov 19, 2014
Priority date	Nov 19, 2014
Publication date	May 19, 2016
Grant date	—

Abstract

A method for inductively coupled communications is described. The method includes generating a retransmitted modulated signal that is stronger than a received signal from a first device. The method also includes generating a suppressed carrier signal from the retransmitted modulated signal for retransmission to the first device. The method further includes filtering a superimposed signal of the suppressed carrier signal on the received signal to attenuate modulation sidebands. The method additionally includes synchronizing to the first device based on the filtered signal.

First claim

What is claimed is:

1 . A method for inductively coupled communications, comprising:
generating a retransmitted modulated signal that is stronger than a received signal from a first device; generating a suppressed carrier signal from the retransmitted modulated signal for retransmission to the first device; filtering a superimposed signal of the suppressed carrier signal on the received signal to attenuate modulation sidebands; and synchronizing to the first device based on the filtered signal.

2 . The method of claim 1 , wherein the retransmitted modulated signal comprises a carrier and modulation sidebands that have greater amplitudes than the received signal.

3 . The method of claim 1 , wherein generating the suppressed carrier signal comprises reducing a carrier amplitude of the retransmitted modulated signal below the amplitude of the received signal.

4 . The method of claim 1 , wherein filtering the superimposed signal to attenuate modulation sidebands comprises reducing the amplitude of modulation sidebands of the superimposed signal below the amplitude of the received signal.

5 . The method of claim 1 , wherein synchronizing to the first device comprises recovering a clock from the received signal using the filtered signal.

6 . The method of claim 5 , wherein synchronizing to the first device further comprises phase locking the suppressed carrier signal to the received signal using phase-locked loop (PLL) circuitry.

7 . The method of claim 5 , wherein the filtering comprises discrete filtering using the recovered clock from the received signal.

8 . The method of claim 1 , wherein the inductively coupled communications is near-field communications (NFC).

9 . The method of claim 1 , wherein the suppressed carrier signal is generated for active load modulation to retransmit a modulated signal.

10 . Circuitry for inductively coupled communications, comprising:
a retransmitted signal generator that generates a retransmitted modulated signal that is stronger than a received signal from a first device; a suppressed carrier signal generator that generates a suppressed carrier signal from the retransmitted modulated signal for retransmission to the first device; a modulation sideband filter that filters a superimposed signal of the suppressed carrier signal on the received signal to attenuate modulation sidebands; and a synchronization block that synchronizes to the first device based on the filtered signal.

11 . The circuitry of claim 10 , wherein the retransmitted modulated signal comprises a carrier and modulation sidebands that have greater amplitudes than the received signal.

12 . The circuitry of claim 10 , wherein generating the suppressed carrier signal comprises reducing a carrier amplitude of the retransmitted modulated signal below the amplitude of the received signal.

13 . The circuitry of claim 10 , wherein filtering the superimposed signal to attenuate modulation sidebands comprises reducing the amplitude of modulation sidebands of the superimposed signal below the amplitude of the received signal.

14 . The circuitry of claim 10 , wherein synchronizing to the first device comprises recovering a clock from the received signal using the filtered signal.

15 . The circuitry of claim 14 , wherein synchronizing to the first device further comprises phase locking the suppressed carrier signal to the received signal using phase-locked loop (PLL) circuitry.

16 . The circuitry of claim 10 , wherein the inductively coupled communications is near-field communications (NFC).

17 . An apparatus for inductively coupled communications, comprising:
means for generating a retransmitted modulated signal that is stronger than a received signal from a first device; means for generating a suppressed carrier signal from the retransmitted modulated signal for retransmission to the first device; means for filtering a superimposed signal of the suppressed carrier signal on the received signal to attenuate modulation sidebands; and means for synchronizing to the first device based on the filtered signal.

18 . The apparatus of claim 17 , wherein the retransmitted modulated signal comprises a carrier and modulation sidebands that have greater amplitudes than the received signal.

19 . The apparatus of claim 17 , wherein the means for generating the suppressed carrier signal comprise means for reducing a carrier amplitude of the retransmitted modulated signal below the amplitude of the received signal.

20 . The apparatus of claim 17 , wherein the means for filtering the superimposed signal to attenuate modulation sidebands comprise means for reducing the amplitude of modulation sidebands of the superimposed signal below the amplitude of the received signal.

21 . The apparatus of claim 17 , wherein the means for synchronizing to the first device comprise means for recovering a clock from the received signal using the filtered signal.

22 . The apparatus of claim 21 , wherein the means for synchronizing to the first device further comprise means for phase locking the suppressed carrier signal to the received signal using phase-locked loop (PLL) circuitry.

23 . The apparatus of claim 17 , wherein the inductively coupled communications is near-field communications (NFC).

24 . A computer-program product for inductively coupled communications, the computer-program product comprising a non-transitory computer-readable medium having instructions thereon, the instructions comprising:
code for causing an apparatus to generate a retransmitted modulated signal that is stronger than a received signal from a first device; code for causing the apparatus to generate a suppressed carrier signal from the retransmitted modulated signal for retransmission to the first device; code for causing the apparatus to filter a superimposed signal of the suppressed carrier signal on the received signal to attenuate modulation sidebands; and code for causing the apparatus to synchronize to the first device based on the filtered signal.

25 . The computer-program product of claim 24 , wherein the retransmitted modulated signal comprises a carrier and modulation sidebands that have greater amplitudes than the received signal.

26 . The computer-program product of claim 24 , wherein the code for causing the apparatus to generate the suppressed carrier signal comprises code for causing the apparatus to reduce a carrier amplitude of the retransmitted modulated signal below the amplitude of the received signal.

27 . The computer-program product of claim 24 , wherein the code for causing the apparatus to filter the superimposed signal to attenuate modulation sidebands comprises the code for causing the apparatus to reduce the amplitude of modulation sidebands of the superimposed signal below the amplitude of the received signal.

28 . The computer-program product of claim 24 , wherein the code for causing the apparatus to synchronize to the first device comprises the code for causing the apparatus to recover a clock from the received signal using the filtered signal.

29 . The computer-program product of claim 28 , wherein the code for causing the apparatus to synchronize to the first device further comprises the code for causing the apparatus to phase lock the suppressed carrier signal to the received signal using phase-locked l

Assignees

• Qualcomm Inc

Inventors

• Gaethke Rainer
• Ghahramani Mohammad Mahdi

Classifications

• H04L27/148 Primary

  using filters, including PLL-type filters · CPC title

• H04W4/80

  Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication · CPC title

• H04W56/0035

  detecting errors in frequency or phase · CPC title

• H04B5/45

  Transponders · CPC title

• H04B5/263

  Multiple coils at either side · CPC title