Multiplex communications – Wide area network – Packet switching
Patent
1986-04-04
1988-05-03
Ng, Jin F.
Multiplex communications
Wide area network
Packet switching
379410, H04B 322
Patent
active
047425105
ABSTRACT:
A method for eliminating echos in modems used for full-duplex data communication is disclosed. The technique improves the cancellation of the echos by synthesizing an estimate of the desired signal and subtracting this estimate from the received waveform to improve the estimate of the residual echo. An adaptive filter is used to match the transmitted bit pattern to make an estimate of the frequency offset in the far echo, so that it can be cancelled more accurately.
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O'Leary Gerald C.
Quatieri, Jr. Thomas F.
Engellenner Thomas J.
Maslow James E.
Massachusetts Institute of Technology
Ng Jin F.
Vaas R.
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