Pulse or digital communications – Receivers – Angle modulation
Reexamination Certificate
2006-05-02
2006-05-02
Deppe, Betsy L. (Department: 2637)
Pulse or digital communications
Receivers
Angle modulation
C375S260000, C375S344000
Reexamination Certificate
active
07039131
ABSTRACT:
An OFDM receiver includes a demodulator for receiving a passband signal having multiple symbols, one or more of the symbols being a reference symbol, and for converting the passband signal to a baseband signal, a CFO compensation circuit for receiving the baseband signal and modifying a phase of the baseband signal in response to a first control signal, a transformation circuit for translating the baseband signal from the CFO compensation circuit into a frequency domain constellation, an equalizer for receiving the frequency domain constellation and modifying the frequency domain constellation based at least in part on the reference symbol, and a CFO estimation circuit coupled between an output of the equalizer and the CFO compensation circuit in a feedback configuration. The CFO estimation circuit is capable of measuring a difference in phase error between multiple symbols received from the equalizer and generating the first control signal, which is representative of the measured phase error difference.
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Agere Systems Inc.
Deppe Betsy L.
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