Telephonic communications – Subscriber line or transmission line interface – Hybrid circuit
Patent
1985-04-22
1987-05-26
Rubinson, Gene Z.
Telephonic communications
Subscriber line or transmission line interface
Hybrid circuit
379410, H04B 152, H04B 320
Patent
active
046691154
ABSTRACT:
An adaptive hybrid circuit for use in a digital telephone switching system is disclosed. The hybrid circuit is adaptive in that it provides cancellation of a far end talker power component in an output signal having both far end talker and near end talker power components. The circuit includes first and second transfer filters for matching loaded and non-loaded subscriber loops, respectively, in the telephone system. The circuit generates a filtered signal representing the difference between loaded and non-loaded subscriber impedances in the telephone system and generates an adaptive control signal responsive to the filtered signal and the output signal such that the far end talker power component is cancelled.
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Myers Randall P.
Regents of the University of California
Rubinson Gene Z.
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