Adaptive RFID receiver for QAM signals

Details Adaptive RFID receiver for QAM signals Adaptive RFID receiver for QAM signals

2011-04-19

2011-04-19

Fan, Chieh M (Department: 2611)

Pulse or digital communications

Systems using alternating or pulsating current

Plural channels for transmission of a single pulse train

C375S260000, C375S259000

Reexamination Certificate

active

07929630

ABSTRACT:
The present invention provides methods and apparatuses for demodulation and decoding of backscattered 16-QAM RFID tag signals, represented by their in-phase and quadrature components at the output of the demodulator in the receiver portion of a reader interrogator. In a communication channel with fast changing parameters, a reader receiver adaptively and coherently corrects the in-phase and quadrature-phase components of a signal received from a tag by tracking the phase and amplitude of the signal based on a decision-feedback. A reference signal is used to correct the signal components, where the coordinates of the reference signal is updated by a tracking and an averaging algorithm. A simple implementation of the receiver in a digital signal processing environment is enabled.

REFERENCES:
patent: 4174489 (1979-11-01), Guidoux et al.
patent: 5867538 (1999-02-01), Liu
patent: 5995019 (1999-11-01), Chieu et al.
patent: 6107910 (2000-08-01), Nysen
patent: 6278746 (2001-08-01), Velez et al.
patent: 6360369 (2002-03-01), Mahoney
patent: 6433671 (2002-08-01), Nysen
patent: 6531957 (2003-03-01), Nysen
patent: 6580358 (2003-06-01), Nysen
patent: 6950009 (2005-09-01), Nysen
patent: 7286614 (2007-10-01), Goldstein et al.
patent: 2004/0114692 (2004-06-01), Matsumoto
patent: 2005/0075103 (2005-04-01), Hikokubo et al.
patent: 2005/0185743 (2005-08-01), Li
patent: 2006/0198449 (2006-09-01), De Bart et al.
patent: 2006/0206290 (2006-09-01), Shin et al.
patent: 2006/0280267 (2006-12-01), Lui et al.
patent: 2006/0291591 (2006-12-01), Ghosh
patent: 2007/0297534 (2007-12-01), Okunev
patent: 2 783 121 (2000-03-01), None
International Search Report and Written Opinion for International Appl. No. PCT/US2007/018582, dated Jan. 29, 2008, 12 pages.
Specification for RFID Air Interface: EPC™ Radio-Frequency Identity Protocols Class-1 Generation-2 UHF RFID Protocol for Communications at 860 MHz—960 MHz: Version 1.0.7, EPCglobal Inc., 93 pages (2004).
Okunev, Yuri, Phase and Phase-Difference Modulation in digital communications, Section 1.5, Artech House, Boston-London, ISBN No. 0-89006-937-9, pp. 36-46 (1997).

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