Pulse or digital communications – Receivers – Angle modulation
Reexamination Certificate
2005-07-26
2005-07-26
Tse, Young T. (Department: 2637)
Pulse or digital communications
Receivers
Angle modulation
C375S332000, C375S344000, C329S300000, C329S304000
Reexamination Certificate
active
06922451
ABSTRACT:
This invention is regarding a frequency shifting circuit suitable for a digital demodulator in a multi-carrier communications system. After converting analog signal vectors to the input signal vectors according to a predetermined sampling clock, control data is generated from a frequency difference between sub-carrier bands and center carrier band. A signal vector rotator is provided corresponding to each of the sub-carrier bands and rotates the input signal vectors on the I-Q plane by an angle determined depending on corresponding control data to shift the sub-carrier bands of the input signal vectors to the center carrier band. A band-pass filter passes an output signal vector of the center carrier band.
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No affiliations
Chang Edith
Dickstein Shapiro Morin & Oshinsky LLP.
Tse Young T.
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