Multiplex communications – Duplex – Transmit/receive interaction control
Patent
1997-04-22
2000-10-17
Olms, Douglas W.
Multiplex communications
Duplex
Transmit/receive interaction control
379334, H04B 320
Patent
active
061342246
ABSTRACT:
An echo canceler is connected to an ISDN Primary Rate Interface. The echo canceler is provided with an activation processor for monitoring call control messages on the D-channel and for selectively enabling or disabling echo cancellation on any of the B-channels in response to information contained within the call control messages. In particular, the activation processor decides whether to enable cancellation depending upon the Information Transfer Capability and Protocol Identification fields of the Bearer Capability portion of a call SETUP message. Additionally, the Channel Identification field of the SETUP message is used to identify the B-channel or channels affected by the SETUP message. When a channel is released, the activation processor maintains enabled echo cancellation as the default condition of the released channel. Other signal processing functions can be controlled by the activation processor in a similar manner.
REFERENCES:
patent: 3673355 (1972-06-01), LeMarche et al.
patent: 3769466 (1973-10-01), Von Pfeil et al.
patent: 3980833 (1976-09-01), Calcagno et al.
patent: 4352962 (1982-10-01), LaMothe
patent: 4469916 (1984-09-01), de Bergh et al.
patent: 4482997 (1984-11-01), Bobsin et al.
patent: 4658420 (1987-04-01), Fukushi et al.
patent: 4736364 (1988-04-01), Basso et al.
patent: 4885755 (1989-12-01), Yoshida
patent: 4982428 (1991-01-01), Agazzi
patent: 5014306 (1991-05-01), Rodgers et al.
patent: 5014307 (1991-05-01), Joffe et al.
patent: 5029204 (1991-07-01), Shenoi et al.
patent: 5117418 (1992-05-01), Chaffee
patent: 5123009 (1992-06-01), Winter
patent: 5131032 (1992-07-01), Esaki
patent: 5148427 (1992-09-01), Buttle
patent: 5153875 (1992-10-01), Takatori
patent: 5163044 (1992-11-01), Golden
patent: 5327489 (1994-07-01), Anderson et al.
patent: 5371534 (1994-12-01), Dagdeviren et al.
patent: 5420921 (1995-05-01), Lahdemaki
patent: 5450487 (1995-09-01), Lahdemaki et al.
patent: 5487109 (1996-01-01), Sutton
patent: 5513183 (1996-04-01), Kay et al.
patent: 5528595 (1996-06-01), Walsh et al.
patent: 5530724 (1996-06-01), Abrams et al.
patent: 5553119 (1996-09-01), McAllister et al.
patent: 5561424 (1996-10-01), Norsworthy et al.
patent: 5588022 (1996-12-01), Dapper et al.
K. Tanzillo, "Echo is a Nagging Problem in Primary Rate Private Network", Communications News, Oct. 1992 (p. 49).
K. Tanzillo, "Answer to Echo Problem", Communications News, Apr. 1994.
"Echo Control in Today's Digital Networks", Steve Jolley, Coherent Feature Article, pp. 1, 7-10 Iss. 2, AT&T 332-415-130, "Functional Description", pp. 2, 2-5, 2-6, 2-10 and 2-11, 1990 AT&T "255 T1 Echo Canceller Modules", Tellabs Technical Manual, 1992, pp. 1, 11-15.
"Coherent Eases Lane Restrictions on the Information Superhighway", Coherent News Release, Mar. 2, 1994, two descriptive text pages, two advertising pages "Automatic Echo Cancellation for ISDN Without Dedicated PRI Channels".
Bielsker Barry
Reese Charles
Berryhill John B.
Olms Douglas W.
Sam Phirin
Tellabs Operations Inc.
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