Multiplex communications – Duplex – Transmit/receive interaction control
Patent
1995-03-03
1996-12-24
Hsu, Alpus H.
Multiplex communications
Duplex
Transmit/receive interaction control
379409, 379410, H04B 320
Patent
active
055879985
ABSTRACT:
A method and apparatus are described for reducing, in communication signals received by a local network from a remote network (FAR-IN signals), that energy content that is attributable to echoes of signals transmitted into the local network (NEAR-IN signals). This is achieved, in part, by generating a time-varying TEMPLATE signal which represents the smoothed energy content of NEAR-IN signals delayed according to the echo path and attenuated by an estimated echo transmission loss. A non-linear processor passes the FAR-IN signal substantially without attenuation if it exceeds the threshold derived at least in part from the TEMPLATE, but attenuates the FAR-IN signal if it lies within a defined range below the threshold.
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Velardo, Jr. Patrick M.
Wynn Woodson D.
AT&T
Hsu Alpus H.
Mayer Stuart H.
Rao Seema S.
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