Multiplex communications – Duplex – Transmit/receive interaction control
Reexamination Certificate
2006-01-24
2006-01-24
Patel, Ajit (Department: 2661)
Multiplex communications
Duplex
Transmit/receive interaction control
C370S289000, C379S406010, C379S406060
Reexamination Certificate
active
06990083
ABSTRACT:
A method of calculating echo-canceling (EC) coefficients to be used by an echo cancellation filter in a communication modem, the communication modem having a Fast Fourier Transform (FFT) serial to parallel interface, the method including the steps of transmitting a first signal including a wide-band cyclic sequence, generating an echo signal based on the first signal and a plurality of EC coefficients, receiving a second signal including a wide-band cyclic sequence, subtracting the echo-canceled signal from the second signal to produce an echo-cancelled signal, transforming the echo-cancelled signal via the FFT serial to parallel interface to produce a transformed echo-cancelled signal, and calculating the plurality of EC coefficients based on the transformed echo-cancelled signal.
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Blount Steven A
Darby & Darby
Patel Ajit
Tioga Technologies Ltd.
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