Multiplex communications – Pathfinding or routing – Switching a message which includes an address header
Reexamination Certificate
1997-12-19
2001-08-28
Nguyen, Chau (Department: 2663)
Multiplex communications
Pathfinding or routing
Switching a message which includes an address header
C370S463000, C370S524000, C370S228000
Reexamination Certificate
active
06282204
ABSTRACT:
A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objections to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE INVENTION
The present invention relates to the field of data and voice frequency communications. By way of example, the present invention is illustrated as a method and apparatus for transmitting and receiving an integrated services digital network (ISDN) 2B+D signal and voice channel over a single twisted pair telephone line.
Techniques for the transmission of multiple voice or data signals via ISDN are well known in the telecommunications industry. An increasing amount of subscribers often desire the use of such conventional ISDN for electronic data processing equipment such as telephones, computers, facsimile machines, modems, and the like in order to take advantage of video conferencing, Internet browsing and access as well as telephone service. However, telephone companies have been reluctant to offer ISDN services for a number of reasons.
One limitation with the provision of conventional ISDN service is that standard ISDN equipment (NT1 device) may experience failure and then leave subscribers without plain old telephone services (POTS). Standard ISDN equipment provides 2B+D (Basic Rate ISDN framing format with 2 basic or bearer (B) channels and 1 data (D) channel) digital services, with both B channels being used to provide data, both B channels being used to provide voice channels, or one B channel being used to provide data and another B channel being used to provide a voice channel. Standard ISDN equipment may thus be used to provide voice telephone service in addition to other digital services, but failure of the ISDN equipment results in failure of all services including the voice telephone service. Therefore, when ISDN service fails, digital telephone service fails with it. It is often desired to have POTS at a customer/subscriber premises as a “back-up ” or “lifeline” service when the conventional ISDN service fails due to ISDN equipment failure or a power outage at the subscriber premises. However, providing this analog phone service conventionally requires adding an additional copper twisted pair line onto a subscriber premises, which may be difficult, costly, and time consuming. That is, because copper is a limited and expensive telephone company resource that may not be available at the desired customer premises, adding an analog telephone line may require breaking concrete and laying down additional copper cable which requires great time and expense.
From the above, it is seen that a method and apparatus for providing ISDN service and voice “lifeline” telephone service from a telephone company central office to a subscriber premises over pre-existing copper wires is desirable.
SUMMARY OF THE INVENTION
The present invention relates to the field of ISDN and telephone communications. More particularly, the present invention provides a method and related apparatus for transmitting and receiving ISDN and POTS information between a central office and subscriber premises over a single twisted pair line, thereby providing a 2:1 pair gain savings in addition to pair gain savings achieved from using ISDN.
According to a specific embodiment, the present invention provides a method of concurrently transmitting and receiving signals representing a voice channel and an ISDN (2B+D) service over a single twisted pair between a first location and a second location. The method includes steps of providing an analog telephone signal and an ISDN signal at a first location, converting the analog telephone signal into a first binary signal, combining the first binary signal and the ISDN signal to a higher rate multiplexed binary signal, and converting the higher rate multiplexed binary signal into a digitally encoded signal. The digitally encoded signal is selected from the group consisting of 2B1Q and 4B3T signals. The method further includes the steps of sending line power over the single twisted pair, transferring the digitally encoded signal to the second location over the single twisted pair, and detecting non-operation of the digitally encoded signal between the first location and the second location to thereby impose a bypass lifeline and provide the analog telephone signal at the second location over the single twisted pair. The method also includes the step of providing the ISDN signal and the analog telephone signal at the second location over the single twisted pair when the non-operation is not detected.
A further understanding of the nature and advantages of this and other specific embodiments of present invention may be realized by reference to the latter portions of the specification and attached drawings.
REFERENCES:
patent: 3308240 (1967-03-01), Von Sanden
patent: 3510584 (1970-05-01), Krasin et al.
patent: 3660606 (1972-05-01), De Witt
patent: 3711650 (1973-01-01), Kuhn et al.
patent: 3824597 (1974-07-01), Berg
patent: 3851106 (1974-11-01), Jacobaeus
patent: 3922493 (1975-11-01), Brenig et al.
patent: 3936602 (1976-02-01), Korver
patent: 4001514 (1977-01-01), Wurst
patent: 4078159 (1978-03-01), Lender et al.
patent: 4100377 (1978-07-01), Flanagan
patent: 4112427 (1978-09-01), Höfer et al.
patent: 4145574 (1979-03-01), Wintzer
patent: 4351049 (1982-09-01), Nobis
patent: 4381427 (1983-04-01), Cheal et al.
patent: 4398284 (1983-08-01), Canniff
patent: 4417333 (1983-11-01), Cochennec
patent: 4519073 (1985-05-01), Bertocci et al.
patent: 4577315 (1986-03-01), Otsuka
patent: 4578538 (1986-03-01), Pascucci et al.
patent: 4642805 (1987-02-01), Dumas et al.
patent: 4644527 (1987-02-01), Anderson et al.
patent: 4689789 (1987-08-01), Herger
patent: 4698801 (1987-10-01), Hatano et al.
patent: 4712210 (1987-12-01), Davis et al.
patent: 4740963 (1988-04-01), Eckley
patent: 4745624 (1988-05-01), Mantovani et al.
patent: 4750169 (1988-06-01), Carse et al.
patent: 4751696 (1988-06-01), Black
patent: 4755994 (1988-07-01), Staples et al.
patent: 4771418 (1988-09-01), Narasimhan et al.
patent: 4788680 (1988-11-01), Kikuchi et al.
patent: 4901344 (1990-02-01), Monette et al.
patent: 4924492 (1990-05-01), Gitlin et al.
patent: 5040190 (1991-08-01), Smith et al.
patent: 5111497 (1992-05-01), Bliven et al.
patent: 5160929 (1992-11-01), Costello
patent: 5198818 (1993-03-01), Samueli et al.
patent: 5208846 (1993-05-01), Hammond et al.
patent: 5216704 (1993-06-01), Williams et al.
patent: 5255317 (1993-10-01), Arai et al.
patent: 5303237 (1994-04-01), Gupta
patent: 5369696 (1994-11-01), Krauss et al.
patent: 5375122 (1994-12-01), Soupirot et al.
patent: 5428682 (1995-06-01), Apfel
patent: 5453989 (1995-09-01), Kitayama et al.
patent: 5459729 (1995-10-01), Bliven
patent: 5459730 (1995-10-01), Bliven
patent: 5473613 (1995-12-01), Bliven
patent: 5610922 (1997-03-01), Balatoni
patent: 5668814 (1997-09-01), Balatoni
patent: 5751741 (1998-05-01), Voith et al.
patent: 5909445 (1999-06-01), Schneider
patent: 0 087 265 A1 (1983-08-01), None
patent: 0 173 984 A2 (1986-03-01), None
patent: 0 227 164 A2 (1987-07-01), None
patent: 0 251 986 A2 (1988-01-01), None
patent: 0 260 470 A3 (1988-03-01), None
patent: 0 370 423 A2 (1990-05-01), None
patent: 59-70395 (1982-10-01), None
patent: 59-211366 (1983-05-01), None
patent: 61-45699 (1984-08-01), None
patent: 62-159561 (1986-01-01), None
patent: WO 85/02960 (1985-07-01), None
patent: WO 95/01600 (1991-02-01), None
patent: WO 91/01600 (1991-02-01), None
Wildman, Bruce R., “Electronic Equipment—Survival In The Outside Plant,”Unknown publication source,believed to have been published on or before Dec. 1988, pp. 629-630.
Letter from Jeff Nash, “2BIQ, U-Interface Line Code Tutorial,”MITEL Semiconductor Product News,Feb. 5, 1987.
Boyer, Gerald R., and Pitchford, Mark, “Universal Digital Channel (UDC)—Synergy With ISDN And The Second Main Line Application,”Unkno
Akers Francis I.
Balatoni Nicholas A.
Nguyen Chau
Nguyen Phuongchau Ba
Terayon Communication Systems, Inc.
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