CA2244000A1 - Line cards for uvg, coin, isdn, and special services - Google Patents
Line cards for uvg, coin, isdn, and special services Download PDFInfo
- Publication number
- CA2244000A1 CA2244000A1 CA 2244000 CA2244000A CA2244000A1 CA 2244000 A1 CA2244000 A1 CA 2244000A1 CA 2244000 CA2244000 CA 2244000 CA 2244000 A CA2244000 A CA 2244000A CA 2244000 A1 CA2244000 A1 CA 2244000A1
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- CA
- Canada
- Prior art keywords
- voice
- services
- signal
- channel unit
- circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M19/00—Current supply arrangements for telephone systems
- H04M19/02—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M17/00—Prepayment of wireline communication systems, wireless communication systems or telephone systems
- H04M17/02—Coin-freed or check-freed systems, e.g. mobile- or card-operated phones, public telephones or booths
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M3/00—Automatic or semi-automatic exchanges
- H04M3/005—Interface circuits for subscriber lines
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q2213/00—Indexing scheme relating to selecting arrangements in general and for multiplex systems
- H04Q2213/13003—Constructional details of switching devices
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q2213/00—Indexing scheme relating to selecting arrangements in general and for multiplex systems
- H04Q2213/1301—Optical transmission, optical switches
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q2213/00—Indexing scheme relating to selecting arrangements in general and for multiplex systems
- H04Q2213/1329—Asynchronous transfer mode, ATM
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q2213/00—Indexing scheme relating to selecting arrangements in general and for multiplex systems
- H04Q2213/13298—Local loop systems, access network
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q2213/00—Indexing scheme relating to selecting arrangements in general and for multiplex systems
- H04Q2213/13322—Integrated circuits
Abstract
A method and apparatus for the generation of special telecommunications services including integrated services digital network (868), coin phone (870), and T1 circuits (a610) on a line card (816) which also supports Plain Old Telephone services (POTs) is presented. In a Fiber-to-the-Curb (FTTC) network configuration a line card (816) containing POTs circuits and special services circuits is used to obtain a close statistical match between the requested number of regular and special telecommunications circuits and the number of circuits available from the optical network unit (ONU)(110).
Description
CA 02244000 l998-09-03 W097/29585 PCT~S97/OlZ45 LINE CARDS FOR WG, COIN, ISDN, AND SPECIAL SERVICES
Cross-References This application claims the benefit of U.S.
Provisional Application No. 60/011,242 filed on February 6 1996 entitled ~Hex and Quad Line Cards fo~
POTs, ISDN and coin services," of which Thomas R. Eames is the inventor, ~ith attorney docket number P708.
This application is also related to US patent application serial number filed on even date herewith, entitled ~Method and Apparatus for Reliable Operation of Universal Voice Grade Cards,"
of which Thomas ~. Eames, Lac X. Trinh, E. Barton Manchester, Bradley N. Yearwood, David J. Manley, Scott T. Hicks, Jaskarn S. Johal, and Charles A. Eldering are the inventors, with attorney docket number M-4066, and which describes the construction and operation of Universal Voice Grade cards.
All of the aforementioned applications are incorporated herein by this reference, but are not admitted to be prior art.
Field Of The Invention The present invention relates to a method and apparatus for delivering Plain Old Telephony (POTs) voice telecommunications services in combination with W097/29585 PCT~S97101245 coin phone, Integrated Service Digital Network (ISDN) and special services.
Bachyl~ul~d Of The Invention Fiber-to-the-curb (FTTC) systems can provide both traditional telecommunications services such as Plain Old Telephony service (POTs), coin phone services, Integrated Services Digital Network (ISDN) and special telecommunications services as well as advanced multimedia services such as Switched Diyital Video (SDV) and high speed data access. Because o~ the range of services which can be supported, it is likely that FTTC systems will be widely deployed ~y telephone companies as they install new lines and upgrade their networks.
FTTC systems typically have equipment in the central o~ice including a Host Digital Terminal (HDT) which is connected by optical ~iber to an Optical Network Unit (ONU), which can be located on a telephone pole or in a pedestal in a neighborhood. For traditional telecommunications services including POTs, coin, ISDN and special services the ONU is connected to subscriber residences by twisted copper pair wire. A
printed circuit board containing electronics and ~requently re~erred to as a channel unit or line card is inserted into the ONU to provide telecommunications services over the twisted copper pair. The ONU
CA 02244000 l99X-09-03 WO g7/29~;85 PCTIUS97/~1245 typically serves between 8 and 16 residences. Each subscriber is provided service by a subscriber circuit on a line card in the ONU
The majority of the subscribers require POTs services which can be provided by a Universal Voice Grade (WG) card. In addition to POTs, the WG card can provide a number of other locally switched special services which include Centrex Lines, Private Branch Exchange (PBX) lines, and 800 number service lines.
The WG card cannot provide coin phone or IDSN services without additional or substantially different circuitry.
In addition to POTs, coin, and ISDN services, there are a number of special locally switched, non-locally switched, digital data, non-switched, DC alarm, and low speed signaling services which a telephone company may need to support, although they may be required by a very small percentage of customers.
In any telephone service area there will be a percentage of subscriber circuits which require either ISDN or coin services. This percentage may be in the range of 6-12~, although the demand for ISDN services is presently growing, and could re~ult ln ~ penetrati3n (as a percentage of homes served) for ISDN services which reaches 25~.
Construction of an ONU is typically such that the line cards (WG or otherwise) can be inserted into the W097/29585 PCT~S97101245 ONU and made operational as additional lines are required. To keep the manu~acturing costs o~ the ONU
as low as possible, it is common to integrate two, ~our or six subscriber circuits on a line card. In the case o~ W G cards this results in what are re~erred to as dual, quad or hex WG line cards. It is also possible that eight subscriber circuits could be integrated on a line card resulting in a octal line card.
Because coin and ISDN services are an important component o~ the services delivered by the ONU, it is necessary to have line cards which can support these services. One approach is to use a special line card which provides one coinicircuit. Similarly, a special card ~or ISDN services can be developed. Having a single circuit on a card allows ~or the possibility o~
closely matching the percentage o~ coin or ISDN
circuits provided with the percentage o~ coin or I~DN
circuits required by inserting the appropriate nu~ber o~ coin or ISDN cards in the ONU. The drawback with this approach is that cards containing a single subscriber circuit are not cost e~ective, due to the ~act that they do not share overhead circuitry with other subscriber circuits, and occupy an entire slot in the ONU.
A second approach to solving this problem is to have a line card which contains ~our or six W G, coin, or ISDN circuits. Since multiple identical circuits CA 02244000 l998-09-03 WO97l29~8~ PCT~S97/0124 are on the same board, a cost savings over multiple individual boards with the same circuit can be realized, and the number of slots required in the ONU
- to serve a given number of subscribers is decreased over that which would be found if dual or single circuit cards are used. The drawback with this approach is that it is difficult to match the percentage of coin or ISDN circuits provided with the percentage of coin or ISDN circuits required since insertion of an ISDN or coin card results in four or six coin or ISDN circuits.
A third approach, the requirements for which has been outlined by Bellcore in their publication TR-TSY-0003~8, entitled "Universal Digital Channel (UDC) Generic Requirements and Objectives," is to use a card which provides existing analog and digital service capability including ISDN service. However, since this card will contain additional circuitry over which is ~ound in a W G card, it will inherently be more costly than a WG card. The aforementioned Bellcore specification is incorporated herein by reference.
Even if these problems for coin phones and ISDN
lines are addressed, there is still the need to provide special services, which will often require a line card with special circuitry.
For the foregoing reasons, there is a need for cost-effective line cards which provide ~or a close W097/29585 PCT~S97/01245 match between the number of coin and ISDN circuits provided, with the number of coin and ISDN circuits required. There i8 also the need for a method of providing special services which does not result in an engineering and cost penalty to the other type of telecommunications circuits in high demand.
Summary Of The Invention In the present invention a channel unit or line card contains a circuit for Plain Old Telephony service ~POTs) and a circuit for a service such as Integrated Services Digital Network (ISDN), coin (pay phone) service, a Tl line, or another type of special service.
Another feature of the present invention is that it allows for multiple POTs circuits in conjunction with a circuit for other types of telecommunications services on one line card. By integrating POTs circuits with circuits for special telecommunications services it is possible to provide the infrequently requested telecommunications services in addition to the commonly used POTs services without having to have a separate line card. In particular, line cards having one coin circuit or one ISDN circuit and five POTs circuits allow for a close statistical match between the number of coin and ISDN circuits required and the number of circuits supported by the equipment. Close matching between the demand and the available circuits CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 prevents having to have partially utilized line cards in the telecommunications equipment, which would require more than the minimum amount of space and power. Optimizing the line card results in a more efficient and cost-ef~ective network.
In a Fiber-to-the-Curb (FTTC) telecommunications architecture, the present invention provides for the deployment of line cards at an Optical Network Unit (ONU) where the line cards have multiple POTs circuits and one ISDN, coin phone, or special service circuit.
The present invention also allows for delivery of special services by generating a Tl circuit on a hybrid Tl line card at an ONU, and transmitting the Tl signal to a special services unit, where a special service line card is used to generate the subscriber interface for that special service. The hybrid Tl line card contains ~our POTs circuits and one Tl circuit, thereby allowing the card to be used for POTs services in addition to the Tl service. Dedicating a line card to Tl service without providing POTs services would utilize an entire slot in the ONU and severely limit the POTs capacity o~ the ONU.
These and other features and objects of the invention will be more fully understood from the following detailed description of the preferred embodiments which should be read in light of the accompanying drawings.
CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 Brie~ Description O~ The Drawings The accompanying drawings, which are incorporated in and form a part o~ the specification, illustrate the embodiments of the present invention and, together with the description serve to explain the principles of the invention.
In the drawings:
FIG. 1 shows a Fiber-to-the-Curb network;
FIG. 2 shows a functional block diagram of a Broadband Network Unit;
FIG. 3 shows a ~unctional block diagram of a dual line Universal Voice Grade card circuit;
FIG. 4 shows a functional block diagram of a dual line Univer~al Voice Grade/ISDN circuit;
15FIG. 5 shows a functional block diagram of a Universal Voice Grade/coin circuit;
FIG. 6 shows a method of delivering special services in a FTTC network using a T1 hybrid card;
FIG. 7 shows an architectural view of a T1 hybrid card; and FIG. 8 shows a ~lock diagram of a T1 circuit.
Detailed De~cription Of The Preferred ~mho~ nt 25In describing a preferred embodiment of the invention illustrated in the drawings, specific terminology will be used for the sake of clarity.
W097/29585 PCT~S97/01245 However, the invention i8 not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.
Table o~ Contents I. Fiber-to-the-curb systems A. System overview B. Broadband Network Unit overview II. Use o~ W G+ cards III. Universal Voice Grade circuit IV. Universal Voice Card + circuits A. W G/ISDN circuit B. W G/coin circuit V. Delivery o~ special services VI. Uses o~ the invention I. Fiber-to-the-curb systems A. SYstem overview FIG. l illustrates a FTTC system which comprises a Broadband Digital Terminal (BDT) lO0, which is connected by an optical ~iber 200 to a Broadband Networ~ Unit (BNU) llO. The BNU llO contains an optical receiver and transmitter to receive signals ~rom and send signals to the BDT lOO, as well one or more Universal Voice Grade cards 140 which connect to CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 residences 175 via twisted pair drop cable 260. In the residence 175 the in-home twisted pair cable 280 connects the telephone 185 to the twisted pair drop cable 260. For the purposes of the present invention, the term Broadband Digital Terminal can be used interchangeably with the term Host Digital Terminal.
Similarly, the term Broadband Network Unit can be used interchangeably with the term Optical Network Unit.
In a typical application BNU 110 serves 8 residences 175, each residence having one or more twisted pair drop cable 260 coming from the BNU 110.
Each BDT 100 typically serves 64 BNUs 110.
The BDT 100 is connected to telecommunications networks via a Public Switched Telecommunication Network (PSTN) switch 10, and networks for advanced services such as the Asynchronous Trans~er Mode IATM) network 7. The interface to the PSTN switch 10 is the switch interface 12, which in the US will be speci~ied by Bellcore specification TR-TSY-000008, TR-NWT-000057 or TR-NWT-000303. The BDT 100 can also receive special services signals from private or non-switched public networks.
The FTTC system can be controlled through the use of an Element Management System (EMS) 150 which is software which runs on a workstation or computer which is connected to the BDT 100. The EMS 150 provides the ability to provision services or equipment which is CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 e~fect the ability to modi~y the state of equipment in the system or provide new services. The EMS 150 can typically be operated locally by an operator at the - workstation or PC, or remotely via a connection through 5 the PSTN switch 10 or the ATM network 7. The EMS 150 also provides the ability to monitor and control the WG cards 140 in the BNU 110.
Telecommunications systems are based on standards which have evolved over many years and insure compatibility o~ equipment from dif~erent manufacturers as well as providing clearly de~ined and precise specifications for different types of telecommunications services so that these services can be provided across geographic boundaries in a network with various generations o~ analog and digital telecommunications equipment. For FTTC systems the Bellcore specification TA-NWT-OOO909, entitled "Generic Requirements and Objectives for Fiber in the Loop Systems,~ Issue 2, December 1993, provides a comprehensive description o~ the requirements ~or FTTC
systems as well as signaling and transmission requirements for W G circuits, and is incorporated herein by reference.
A WG circuit is de~ined as one which can provide either a loop start or ground start line/trunk interface with no intervention by a cra~tsperson at the ~ site o~ the W G circuit. In the present embodiments, CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 the UVG card 140 supports 13 of the 14 locally switched special services as described in Section 3.1 of the Bellcore specification TA-NWT-000909, entitled "Generic Requirements and Objectives for Fiber in the ~oop Systems." The service not supported is Data Inward Dial ~DID).
B. Broadband Network Unit overview A block diagram of the BNU 110 shown in FIG. 1 is illustrated in FIG. 2. The BNU 110 contains a Broadband Network Unit Power Supply (BNPS) 804 which receives a voltage ~rom an external source at power supply header 848, and can power terminal equipment by connections made at a 4-drop header 856. The BNU 110 further contains a BNU Common Control (BNCC) 800 which receives signals from optical fiber 200 at an optical connector 844. The BNCC 800 contains the circuitry to send and receive optical si~nals, as well as a microprocessor and associated software to communicate 20 with the BDT 100 and control the WG cards 140.
As illustrated in FIG. 2, the BNU 110 can contain UVG cards 140 which further contain a dual line WG
circuit 812. The dual line UVG circuit is further illustrated in FIG. 3. As shown in FIG. 2, the BNU 110 can also contain W G+ circuits 818 which may be a WG/coin circuit 816 such as the one shown in FIG. 5, a WG/ISDN circuit 814 such as the one shown in FIG. 6, a CA 02244000 l998-09-03 WO 97/29585 PCTIUS97/0124~;
WG/special services circuit, or a W G/Tl circuit.
Multiple embodiments o~ the BNU 110 are possible, a first embodiment being a BNU-8 which nominally serves 8 residences 175 and can contain up to two insertable WG cards 140, two insertable W G+ cards 141 or a combination thereof.
An alternate embodiment o~ BNU 110 is a BNU-16 which nominally serves 16 residences 175 and can contain up to ~our insertable W G cards 140, ~our insertable W G+ cards 141 or a combination thereof.
The WG cards 140 may have ~rom one to four dual line W G circuits 812, and the WG+ card 141 may have one W G/coin circuit 816 with the remainder o~ the circuits being W G circuits 812, or it may have one WG/ISDN circuit 814 with the remainder o~ the circuits being W G circuits 812. Hex cards which have three dual line WG circuits 812 are believed to be the most cost e~ective, as are hex cards with two dual line WG
circuits 812 and one W G/coin circuit 816, or hex line cards with two dual line WG circuits 812 and one WG/ISDN circuit 814.
II. Use o~ W G+ cards Tables I and II illustrate the services supported by a BNU-8 and BNU-16 respectively with various combinations o~ hex or quad WG and hex or quad WG+
cards. From these tables it can be seen that the use CA 02244000 l998-09-03 W O 97/29585 PCTrUS97/~12~5 of WG+ cards allows the IDSN or coin penetration supported to vary from 09~ to 25~. This can be accomplished with an inventory of no more than 6 cards:
hex and quad W~ cards 14 0, hex and quad WG+ cards 141 containing one coin/l~VG circuit 816, and hex and quad WG+ cards 141 containing one ISDN/WG circui'c 814 .
Alternately, by maintaining an inventory of 4 cards only (hex WG cards 140, hex WG~ cards 141 containing one coin/WG circuit 816, and hex WG+ cards 141 containing one ISDN/WG circuit 814) the same range o~ penetration can be achieved, but with fewer increment s .
The WG penetration supported exceeds 100~ when some number of subscribers request a second telephone line for a WG service. For this reason greater than 100~ penetration occurs in Tables I and II.
Table I
Services supported by BNU 8 with W G and W G+ cards WG quad WG+ quad WG hex WG+ hex WG ISND/coin car~scardscard3cardspenetration penetration supported supported 2 lO0 00~ 0.00 1 1 125.00~ o.00 2 150 00~ o 00~
1 1 87 50~ 12 50%
1 1 137 50~ 12.50 1 1 112 50% 12 50 1 1 112.50% 12.50~
1 1 100 00~ 25.00%
2 75 00~ 25 00~
2 125.00~ 25 00%
CA 02244000 l998-09-03 WO 97l29585 PCT/US97/0124 Table II
Servicect ~upported by BNU 16 with WG and WG+ cards WG quad UVG+ quad WG hex WG+ hex UVG ISND/coin cards card3 cards cards penetration penetration supported supported 4 100.00% 0.00~
Cross-References This application claims the benefit of U.S.
Provisional Application No. 60/011,242 filed on February 6 1996 entitled ~Hex and Quad Line Cards fo~
POTs, ISDN and coin services," of which Thomas R. Eames is the inventor, ~ith attorney docket number P708.
This application is also related to US patent application serial number filed on even date herewith, entitled ~Method and Apparatus for Reliable Operation of Universal Voice Grade Cards,"
of which Thomas ~. Eames, Lac X. Trinh, E. Barton Manchester, Bradley N. Yearwood, David J. Manley, Scott T. Hicks, Jaskarn S. Johal, and Charles A. Eldering are the inventors, with attorney docket number M-4066, and which describes the construction and operation of Universal Voice Grade cards.
All of the aforementioned applications are incorporated herein by this reference, but are not admitted to be prior art.
Field Of The Invention The present invention relates to a method and apparatus for delivering Plain Old Telephony (POTs) voice telecommunications services in combination with W097/29585 PCT~S97101245 coin phone, Integrated Service Digital Network (ISDN) and special services.
Bachyl~ul~d Of The Invention Fiber-to-the-curb (FTTC) systems can provide both traditional telecommunications services such as Plain Old Telephony service (POTs), coin phone services, Integrated Services Digital Network (ISDN) and special telecommunications services as well as advanced multimedia services such as Switched Diyital Video (SDV) and high speed data access. Because o~ the range of services which can be supported, it is likely that FTTC systems will be widely deployed ~y telephone companies as they install new lines and upgrade their networks.
FTTC systems typically have equipment in the central o~ice including a Host Digital Terminal (HDT) which is connected by optical ~iber to an Optical Network Unit (ONU), which can be located on a telephone pole or in a pedestal in a neighborhood. For traditional telecommunications services including POTs, coin, ISDN and special services the ONU is connected to subscriber residences by twisted copper pair wire. A
printed circuit board containing electronics and ~requently re~erred to as a channel unit or line card is inserted into the ONU to provide telecommunications services over the twisted copper pair. The ONU
CA 02244000 l99X-09-03 WO g7/29~;85 PCTIUS97/~1245 typically serves between 8 and 16 residences. Each subscriber is provided service by a subscriber circuit on a line card in the ONU
The majority of the subscribers require POTs services which can be provided by a Universal Voice Grade (WG) card. In addition to POTs, the WG card can provide a number of other locally switched special services which include Centrex Lines, Private Branch Exchange (PBX) lines, and 800 number service lines.
The WG card cannot provide coin phone or IDSN services without additional or substantially different circuitry.
In addition to POTs, coin, and ISDN services, there are a number of special locally switched, non-locally switched, digital data, non-switched, DC alarm, and low speed signaling services which a telephone company may need to support, although they may be required by a very small percentage of customers.
In any telephone service area there will be a percentage of subscriber circuits which require either ISDN or coin services. This percentage may be in the range of 6-12~, although the demand for ISDN services is presently growing, and could re~ult ln ~ penetrati3n (as a percentage of homes served) for ISDN services which reaches 25~.
Construction of an ONU is typically such that the line cards (WG or otherwise) can be inserted into the W097/29585 PCT~S97101245 ONU and made operational as additional lines are required. To keep the manu~acturing costs o~ the ONU
as low as possible, it is common to integrate two, ~our or six subscriber circuits on a line card. In the case o~ W G cards this results in what are re~erred to as dual, quad or hex WG line cards. It is also possible that eight subscriber circuits could be integrated on a line card resulting in a octal line card.
Because coin and ISDN services are an important component o~ the services delivered by the ONU, it is necessary to have line cards which can support these services. One approach is to use a special line card which provides one coinicircuit. Similarly, a special card ~or ISDN services can be developed. Having a single circuit on a card allows ~or the possibility o~
closely matching the percentage o~ coin or ISDN
circuits provided with the percentage o~ coin or I~DN
circuits required by inserting the appropriate nu~ber o~ coin or ISDN cards in the ONU. The drawback with this approach is that cards containing a single subscriber circuit are not cost e~ective, due to the ~act that they do not share overhead circuitry with other subscriber circuits, and occupy an entire slot in the ONU.
A second approach to solving this problem is to have a line card which contains ~our or six W G, coin, or ISDN circuits. Since multiple identical circuits CA 02244000 l998-09-03 WO97l29~8~ PCT~S97/0124 are on the same board, a cost savings over multiple individual boards with the same circuit can be realized, and the number of slots required in the ONU
- to serve a given number of subscribers is decreased over that which would be found if dual or single circuit cards are used. The drawback with this approach is that it is difficult to match the percentage of coin or ISDN circuits provided with the percentage of coin or ISDN circuits required since insertion of an ISDN or coin card results in four or six coin or ISDN circuits.
A third approach, the requirements for which has been outlined by Bellcore in their publication TR-TSY-0003~8, entitled "Universal Digital Channel (UDC) Generic Requirements and Objectives," is to use a card which provides existing analog and digital service capability including ISDN service. However, since this card will contain additional circuitry over which is ~ound in a W G card, it will inherently be more costly than a WG card. The aforementioned Bellcore specification is incorporated herein by reference.
Even if these problems for coin phones and ISDN
lines are addressed, there is still the need to provide special services, which will often require a line card with special circuitry.
For the foregoing reasons, there is a need for cost-effective line cards which provide ~or a close W097/29585 PCT~S97/01245 match between the number of coin and ISDN circuits provided, with the number of coin and ISDN circuits required. There i8 also the need for a method of providing special services which does not result in an engineering and cost penalty to the other type of telecommunications circuits in high demand.
Summary Of The Invention In the present invention a channel unit or line card contains a circuit for Plain Old Telephony service ~POTs) and a circuit for a service such as Integrated Services Digital Network (ISDN), coin (pay phone) service, a Tl line, or another type of special service.
Another feature of the present invention is that it allows for multiple POTs circuits in conjunction with a circuit for other types of telecommunications services on one line card. By integrating POTs circuits with circuits for special telecommunications services it is possible to provide the infrequently requested telecommunications services in addition to the commonly used POTs services without having to have a separate line card. In particular, line cards having one coin circuit or one ISDN circuit and five POTs circuits allow for a close statistical match between the number of coin and ISDN circuits required and the number of circuits supported by the equipment. Close matching between the demand and the available circuits CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 prevents having to have partially utilized line cards in the telecommunications equipment, which would require more than the minimum amount of space and power. Optimizing the line card results in a more efficient and cost-ef~ective network.
In a Fiber-to-the-Curb (FTTC) telecommunications architecture, the present invention provides for the deployment of line cards at an Optical Network Unit (ONU) where the line cards have multiple POTs circuits and one ISDN, coin phone, or special service circuit.
The present invention also allows for delivery of special services by generating a Tl circuit on a hybrid Tl line card at an ONU, and transmitting the Tl signal to a special services unit, where a special service line card is used to generate the subscriber interface for that special service. The hybrid Tl line card contains ~our POTs circuits and one Tl circuit, thereby allowing the card to be used for POTs services in addition to the Tl service. Dedicating a line card to Tl service without providing POTs services would utilize an entire slot in the ONU and severely limit the POTs capacity o~ the ONU.
These and other features and objects of the invention will be more fully understood from the following detailed description of the preferred embodiments which should be read in light of the accompanying drawings.
CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 Brie~ Description O~ The Drawings The accompanying drawings, which are incorporated in and form a part o~ the specification, illustrate the embodiments of the present invention and, together with the description serve to explain the principles of the invention.
In the drawings:
FIG. 1 shows a Fiber-to-the-Curb network;
FIG. 2 shows a functional block diagram of a Broadband Network Unit;
FIG. 3 shows a ~unctional block diagram of a dual line Universal Voice Grade card circuit;
FIG. 4 shows a functional block diagram of a dual line Univer~al Voice Grade/ISDN circuit;
15FIG. 5 shows a functional block diagram of a Universal Voice Grade/coin circuit;
FIG. 6 shows a method of delivering special services in a FTTC network using a T1 hybrid card;
FIG. 7 shows an architectural view of a T1 hybrid card; and FIG. 8 shows a ~lock diagram of a T1 circuit.
Detailed De~cription Of The Preferred ~mho~ nt 25In describing a preferred embodiment of the invention illustrated in the drawings, specific terminology will be used for the sake of clarity.
W097/29585 PCT~S97/01245 However, the invention i8 not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.
Table o~ Contents I. Fiber-to-the-curb systems A. System overview B. Broadband Network Unit overview II. Use o~ W G+ cards III. Universal Voice Grade circuit IV. Universal Voice Card + circuits A. W G/ISDN circuit B. W G/coin circuit V. Delivery o~ special services VI. Uses o~ the invention I. Fiber-to-the-curb systems A. SYstem overview FIG. l illustrates a FTTC system which comprises a Broadband Digital Terminal (BDT) lO0, which is connected by an optical ~iber 200 to a Broadband Networ~ Unit (BNU) llO. The BNU llO contains an optical receiver and transmitter to receive signals ~rom and send signals to the BDT lOO, as well one or more Universal Voice Grade cards 140 which connect to CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 residences 175 via twisted pair drop cable 260. In the residence 175 the in-home twisted pair cable 280 connects the telephone 185 to the twisted pair drop cable 260. For the purposes of the present invention, the term Broadband Digital Terminal can be used interchangeably with the term Host Digital Terminal.
Similarly, the term Broadband Network Unit can be used interchangeably with the term Optical Network Unit.
In a typical application BNU 110 serves 8 residences 175, each residence having one or more twisted pair drop cable 260 coming from the BNU 110.
Each BDT 100 typically serves 64 BNUs 110.
The BDT 100 is connected to telecommunications networks via a Public Switched Telecommunication Network (PSTN) switch 10, and networks for advanced services such as the Asynchronous Trans~er Mode IATM) network 7. The interface to the PSTN switch 10 is the switch interface 12, which in the US will be speci~ied by Bellcore specification TR-TSY-000008, TR-NWT-000057 or TR-NWT-000303. The BDT 100 can also receive special services signals from private or non-switched public networks.
The FTTC system can be controlled through the use of an Element Management System (EMS) 150 which is software which runs on a workstation or computer which is connected to the BDT 100. The EMS 150 provides the ability to provision services or equipment which is CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 e~fect the ability to modi~y the state of equipment in the system or provide new services. The EMS 150 can typically be operated locally by an operator at the - workstation or PC, or remotely via a connection through 5 the PSTN switch 10 or the ATM network 7. The EMS 150 also provides the ability to monitor and control the WG cards 140 in the BNU 110.
Telecommunications systems are based on standards which have evolved over many years and insure compatibility o~ equipment from dif~erent manufacturers as well as providing clearly de~ined and precise specifications for different types of telecommunications services so that these services can be provided across geographic boundaries in a network with various generations o~ analog and digital telecommunications equipment. For FTTC systems the Bellcore specification TA-NWT-OOO909, entitled "Generic Requirements and Objectives for Fiber in the Loop Systems,~ Issue 2, December 1993, provides a comprehensive description o~ the requirements ~or FTTC
systems as well as signaling and transmission requirements for W G circuits, and is incorporated herein by reference.
A WG circuit is de~ined as one which can provide either a loop start or ground start line/trunk interface with no intervention by a cra~tsperson at the ~ site o~ the W G circuit. In the present embodiments, CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 the UVG card 140 supports 13 of the 14 locally switched special services as described in Section 3.1 of the Bellcore specification TA-NWT-000909, entitled "Generic Requirements and Objectives for Fiber in the ~oop Systems." The service not supported is Data Inward Dial ~DID).
B. Broadband Network Unit overview A block diagram of the BNU 110 shown in FIG. 1 is illustrated in FIG. 2. The BNU 110 contains a Broadband Network Unit Power Supply (BNPS) 804 which receives a voltage ~rom an external source at power supply header 848, and can power terminal equipment by connections made at a 4-drop header 856. The BNU 110 further contains a BNU Common Control (BNCC) 800 which receives signals from optical fiber 200 at an optical connector 844. The BNCC 800 contains the circuitry to send and receive optical si~nals, as well as a microprocessor and associated software to communicate 20 with the BDT 100 and control the WG cards 140.
As illustrated in FIG. 2, the BNU 110 can contain UVG cards 140 which further contain a dual line WG
circuit 812. The dual line UVG circuit is further illustrated in FIG. 3. As shown in FIG. 2, the BNU 110 can also contain W G+ circuits 818 which may be a WG/coin circuit 816 such as the one shown in FIG. 5, a WG/ISDN circuit 814 such as the one shown in FIG. 6, a CA 02244000 l998-09-03 WO 97/29585 PCTIUS97/0124~;
WG/special services circuit, or a W G/Tl circuit.
Multiple embodiments o~ the BNU 110 are possible, a first embodiment being a BNU-8 which nominally serves 8 residences 175 and can contain up to two insertable WG cards 140, two insertable W G+ cards 141 or a combination thereof.
An alternate embodiment o~ BNU 110 is a BNU-16 which nominally serves 16 residences 175 and can contain up to ~our insertable W G cards 140, ~our insertable W G+ cards 141 or a combination thereof.
The WG cards 140 may have ~rom one to four dual line W G circuits 812, and the WG+ card 141 may have one W G/coin circuit 816 with the remainder o~ the circuits being W G circuits 812, or it may have one WG/ISDN circuit 814 with the remainder o~ the circuits being W G circuits 812. Hex cards which have three dual line WG circuits 812 are believed to be the most cost e~ective, as are hex cards with two dual line WG
circuits 812 and one W G/coin circuit 816, or hex line cards with two dual line WG circuits 812 and one WG/ISDN circuit 814.
II. Use o~ W G+ cards Tables I and II illustrate the services supported by a BNU-8 and BNU-16 respectively with various combinations o~ hex or quad WG and hex or quad WG+
cards. From these tables it can be seen that the use CA 02244000 l998-09-03 W O 97/29585 PCTrUS97/~12~5 of WG+ cards allows the IDSN or coin penetration supported to vary from 09~ to 25~. This can be accomplished with an inventory of no more than 6 cards:
hex and quad W~ cards 14 0, hex and quad WG+ cards 141 containing one coin/l~VG circuit 816, and hex and quad WG+ cards 141 containing one ISDN/WG circui'c 814 .
Alternately, by maintaining an inventory of 4 cards only (hex WG cards 140, hex WG~ cards 141 containing one coin/WG circuit 816, and hex WG+ cards 141 containing one ISDN/WG circuit 814) the same range o~ penetration can be achieved, but with fewer increment s .
The WG penetration supported exceeds 100~ when some number of subscribers request a second telephone line for a WG service. For this reason greater than 100~ penetration occurs in Tables I and II.
Table I
Services supported by BNU 8 with W G and W G+ cards WG quad WG+ quad WG hex WG+ hex WG ISND/coin car~scardscard3cardspenetration penetration supported supported 2 lO0 00~ 0.00 1 1 125.00~ o.00 2 150 00~ o 00~
1 1 87 50~ 12 50%
1 1 137 50~ 12.50 1 1 112 50% 12 50 1 1 112.50% 12.50~
1 1 100 00~ 25.00%
2 75 00~ 25 00~
2 125.00~ 25 00%
CA 02244000 l998-09-03 WO 97l29585 PCT/US97/0124 Table II
Servicect ~upported by BNU 16 with WG and WG+ cards WG quad UVG+ quad WG hex WG+ hex UVG ISND/coin cards card3 cards cards penetration penetration supported supported 4 100.00% 0.00~
3 1 112.50~ 0,00%
2 2 125.00~ 0.00%
1 3 137.50% 0,00%
2 2 125.00~ 0.00%
1 3 137.50% 0,00%
4 150.00% 0.00%
0 3 1 93.75% 6.25%
2 2 87 50% 12.50%
1 3 81.25% 18.75%
1 1 1 l112 50~ 12.50%
2 1 1106 . 25%18 75.
2 2137 50 12.50 2 1 1118.75 6 . 25~
1 1 2 118 75 6 . 25%
3 1106 . 25 6.25%
1 3118.75 18.75~
3 1 93.75 18.75%
1 3 131.25 6.25~
2 2 112 50 12.50%
4 75.00 25 00%
4125.00 25 00%
1 3 131 25 18.75~
1 3112 50 25 00%
3 1 143.75 6 . 25%
3 187.50 25.00%
III. Universal Voice Grade circuit The W G card 140 illustrated in FIGS. 2 and 3 provides POTs service to a number of residences 175 served by a BNU 110, and can provide this service through a Loop Start or Ground Start line/trunk interface. Typically, 6 ~ubscriber voice circuits (POTs lines) are served from a W G card 140. Referring W097/29585 PCT~S97/01245 to FIG . 2 the WG card 140 contains three dual line WG
circuits 812 such as the one illustrated in FIG. 3.
WG card connectors 860 allow connection of the WG card to backplane interconnects 808 which provide connectivity to the BNCC 800. The backplane interconnectg 808 provides connections to a number of signals including data buses which contain telecommunications data for subscribers as well as control information from the BDT 100 or the BNCC 800, and power and ground for the WG card itself.
Referring again to FIG. 3, the WG card contains a common control bus signal 882 which connects a Telephony Inter~ace Unit Application Specific Integrated Circuit (TIUA) 880 to BNCC 800.
TIUA 880 provides the time division multiplexing functions, state machine functions, and general control functions for the generation o~ a voice signals in conjunction with the other components of WG circuit 812.
An Electrically Erasable Programmable Read Only Memory (EEPROM) 886 is used in conjunction with TIUA 880 for the storage of operational data required when WG
card 140 is initially powered.
In addition to TIUA 880, each WG card 140 also includes a microcontroller and SRAM. These are indicated respectively by re~erence characters 884 and 887. Microcontroller 884 may be implemented using WO 97/29~i85 PCT/US97/01245 generally available products such as ~or example a Motorola 68HCllD3, and a suitable design choice for SRAM 887 is a 32K x 8 SRAM. A suitable SRAM for this purpose lS an Integrated Devices Technology SRAM
denoted IDT 712565A. Of course other manufacturer's devices having the indicated source capacity may also be used as a substitute.
A ringing generator 890 is included on the WG
card 140, which is capable of providing 40 V RMS into a 5 ringing equivalent (REN) load. Ringing generator 890 is controlled by a digital pulse train 892 ~rom TIUA
880, and receives a -130 V signal 894. The output o~
the ringing generator is ringing voltage 896.
A Pulse Code Modulated (PCM) bus 883 and serial bus 885 transfer signals to and ~rom TIUA 880 to subscriber line audio circuits. A single component known as a dual audio line subscriber audio circuit is used to provide a first audio line subscriber audio circuit 900 and a second subscriber line audio circuit 902 in dual line WG circuit 812 The Advanced Micro Devices' product denoted AM79C031, known by its trademarked name as DSLAC~ is a suitable design choice.
When used herein, the term DSLAC~ re~ers generically to a dual subscriber line audio circuit. An alternate design choice for a dual audio line subscriber audio circuit is the Siemens SiCoFi device.
The DSLAC~s are connected to a Subscriber Line CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 Interface Circuit (SLIC) 906. There are two SLICs 906 in each dual line W G circuit 812. In addition to generating the voice circuit interface for basic telephone service, each SLIC also performs loop sense and ring trip detection, tip and ring polarity reversals, provides ring delay drivers and provides a battery switch function to allow two different battery voltages to be used. Subscriber line interface circuits 906 may be implemented utilizing commercially available devices such as the Advanced Micro Devices product denoted AM7949.
A solid state relay 91O is used in each subscriber circuit to allow the application of the ringing voltage 896 through a lOO Q ringing resistor 898, as well as for providing metallic test access from the test in bus 912 and test out bus 914 toward the communications channel formed by the WG circuit and toward the twisted pair drop cable 260. AT&T part number ATTL7583 is a suitable design choice for solid state relay 910.
A transient over-voltage protector 918 is used to protect the solid state relay 91O from excessive voltages. A suitable design choice for the transient over-voltage protector 918 is the Teccor P2103 200 V
Sidactor.
Protection resistor 920 consists of two resistors, one in series with the tip (T) line 266 and on in series with the ring (R) line 268 which together form CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 the twisted pair drop cable 260. The protection resistors serve to protect the WG circuit from overvoltages, in particular overvoltages due to lightning strikes. Thick ~ilm or wirewound ~usible protection resistors are typically used. A suitable design choice ~or a protection resistor in protection resistor 920 is a 50 Q thick film resistor on a ceramic substrate.
A gas tube or carbon block device at the premises is used in conjunction with the transient over-voltage protector 918 and protection resistor to provide over-voltage protection. Protection resistor 920 presents suf~icient resistance such that in the event o~ a lightning strike the voltage at the premises will -15 remain su~iciently high to activate the gas tube or carbon block in addition to activating transient over-voltage protector 918.
IV. Universal Voice Card + circuits A. WG/ISDN circuit The WG/ISDN circuit 814 is illustrated in FIG. 4.
The circuit can provide ISDN Basic Access using 3-DS0 or 4:1 multiplexing. The inter~ace to the subscriber is a U-inter~ace operating over two wires at a data rate of 160 kb/s ~ull duplex.
The PCM bus 883 interconnects the TIU ASIC 880 with the U transceiver 862. The U transceiver 862 WO 97/29585 PCT/US97/012'~5 provides basic ISDN Basic Access functionality as described in the American National Standards Institute T1.601-1991 specification. ~ suitable design choice for the U transceiver 862 is the Siemens ISDN
Echocancellation Circuit IEC-Q 2091.
The U transceiver 862 is connected to the 4-2 wire hybrid 864 which converts half duplex transmission to full duplex transmission at the U interface. The 4-2 wire hybrid 864 can be realized using resistors and capacitors or with a single IC such as the Pulse Engineering PE36005W single chip hybrid.
The 4-2 wire hybrid is connected to the transformer 865. A suitable design choice for the 4-2 wire hybrid is the Pulse Engineering PE-65575 line transformer.
The transformer 865 is connected to a solid state relay 910 which provides access for the test in bus 912 and test out bus 914. Switching in and out of ringing is not required in the ISDN application.
A transient over-voltage protector 918 is used to protect the solid state relay 910 from excessive voltages. A suitable design choice for the transient over-voltage protector 918 is the Teccor P2103 200 V
Sidactor.
Following the transient over-voltage protector 918 a Positive Temperature Coefficient (PTC) device 866 is used to protect the circuit from excessive currents.
CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 B. WG/coin circuit The WG/coin circuit 814 is illustrated in FIG. 5.
Operation of the WG/coin circuit 814 is similar to - that of the W G circuit 812 with the addition of coin check/control 872 which permits the application of the four coin voltages: +48V, 874; -48V, 876; +80V, 878;
and -80V, 879. These voltages are used to control the functions of coin collect, coin refund, coin presence check, and coin base amount check, and keypad disable.
10 The voltages 874, 876, 878 and 879 are applied via the solid state relay 910.
The requirements for coin signaling are described in detail in Section 4.6 of Bellcore specification TA-NWT-O009O9, entitled "Generic Requirements and Objectives for Fiber in the Loop Systems," Issue 2, December 1993. Circuits for meeting these signaling requirements are known by those skilled in the art.
V. Delivery of s~ecial services Because there is a re~uirement to provide special services in addition to POTs, coin, and ISDN lines, there is a need for a method and apparatus of delivering those services efficiently from the BNU 110.
FIG. 6 illustrates a method in which special services are delivered from BNU 110 by the use of a T1 hybrid card A610, which includes POTs circuits and one - T1 circuit. The T1 circuit is used to provide a T1 CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 signal containing 24 DS0's to a Special Service Unit-8 (SSU-8) A620, which has plug-in cards for special services. The special services are then provided using a telecommunications link A618 and appropriate Customer Premises Equipment (CPE) A630. By providing special services in this way it is not necessary to have special service cards resident in BNU 110.
Referring to FIG. 6, delivery of special services is accomplished by providing DS0 channels to BDT 100 either by means of a D4 signal A604 which contains up to 24 special services circuits, or by using a Central Office Terminal Channel Bank A600 which receives unbundled specials signals A602 and ~orms a DSl signal A601. Signals are transported to BNU 110 via optical 1~ fiber 200. Tl hybrid card A610 provides a Tl signal over a four-wire twisted pair loop A623 to a Special Service Unit-8 (SSU-8) A620. SSU-8 A620 accepts whatever type of special services card is needed to provide the special service. Telecommunications link A618 can be twisted pair, coaxial cable, or any other type of telecommunications link required ~or the special service.
The special service unit shown in FIG. 6 as SSU-8 A620 can be located inside of a building, or can be located outside on a telephone pole or in any other suitable location for network equipment. A number of existing channel banks can be used as special service CA 02244000 l998-09-03 WO 97~29!;85 PCT/US97/01245 unit, and the size o~ the special service unit can vary ~rom a two-card unit up to a 24 card unit. The construction of channel banks is well understood by - those skilled in the art.
In addition to providing special services, T1 hybrid card A610 contains four POTs circuits, and can provide POTs services to residences 175 using via twisted pair drop cable 260. In the residence 175 the in-home twisted pair cable connects the telephone 185 to the twisted pair drop cable 260.
FIG. 7 illustrates the T1 hybrid card A610 in ~urther detail, showing ~our POTs circuits, POTS1 A72Oa, POTS2 A72Ob, POTs3 A720c, and POTS4 A72Od. A
DS1 circuit A730 is present to transmit and receive the 15 T1 signal to and ~rom SSU-8 A620. The DS1 common daughter board A710 plugs into the mother board A709 and provides the inter~ace ~unction to the BNCC 800.
The DS1 common daughter board A710 contains a T1 ASIC
A818, T1 microprocessor A822, external T1 Static Random 20 Access Memory (T1 S~AM) A826, and T1 ~P SRAM A824. A
separate processor (microcontroller) is used ~or the T1 circuit ~unctions in order not to burden the microcontroller 824 which is used ~or POTs circuit functions.
The common POTs block A740 provides the functions common to all o~ the POTs circuits. Included in the common POTs block A740 are the microcontroller 884, CA 02244000 l998-09-03 W097129~85 PCT~S97/01245 SRAM 887 TIUA 880, EEPROM 886, and ringing generator 890 illustrated in FIG. 3.
The DS1 clrcuit A730 is comprised of the clock adapter A820, framer A816, and Line Interface Unit ~LIU) A814.
A block diagram of the entire T1 circuit is illustrated in further detail in FIG. 8. The receive pair A810 and transmit pair A812 which form the four-wire twisted pair loop A623 are connected to the ~ine Interface Unit (LIU) A814. A suitable design choice for the ~IU A814 is the Level One LXT350 short haul TltE1 Transceiver.
A ~ramer A816 per~orms the ~raming ~unctions on the received and transmitted signals. A suitable design choice for ~ramer A816 is the BT8360.
A clock adapter A820 is used to generate a 1. 544 MHz clock A823 ~rom the 4.096 MHz clock A821 which is present on the hybrid T1 card A610. A suitable design choice ~or the clock adapter is the Level One LXP604 Clock Adapter.
The Tl ASIC A818 is used to form the Tl signal ~rom the BNU payload. Tl ASIC A818 is connected to TIU
BUS 882 which is connected to BNCC 800 via backplane interconnects 808. The Tl ASIC A818 is responsible for interfacing to backplane interconnects 808 and provides the processor interface and address decoding.
TI ASIC A818 stores a 4 ~rame downstream signaling CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 history and translates upstream and downstream signaling on a per DS0 basis.
External T1 Static Random Access Memory (T1 SRAM) A826 is utilized in conjunction with T1 ASIC A818 for storing 4 signaling ~rames required for signaling freeze conditions. The T1 SRAM A826 is also used for storing downloaded signaling translation tables. The processor loads the tables via a memory banking method, through T1 ASIC A818. A suitable design choice for the size of T1 SRAM A826 is 32K*8, although only a few hundred bytes of memory may be required in actual operation.
A microprocessor A822 is used to configure the various components on the T1 hybrid card A610. A
suitable design choice is a Motorola 68HCllD3 microprocessor running at 2MHz. The microprocessor A822 will download code from the BNCC 800 via the data-link. External ~P Static Random Access Memory (~P
SRAM) A824 is utilized for storage of program information. A suitable design choice for the size of the ~P SRAM A824 is a 128K*8 SRAM, although only 64K is addressable space. The microprocessor A822 performs any necessary alarm monitoring and performance monitoring functions required, along with initialization of the LIU A814, framer A816, and T1 SRAM A826.
In a preferred embodiment, four POTs circuits are WO 971~9585 PCT/US97/01245 placed on a T1 Hybrid Card with one T1 circuit. This is because 2 twisted wire pairs are used ~or T1 service, and there are 6 pairs available ~or each WG
card 140, W G+ card 141, or Tl hybrid card A610. In an alternate embodiment, 5 POTs circuits can be placed on a card with one Tl circuit. This alternate embodiment requires connections ~or an additional twisted pair In an alternate embodiment the special service circuits can be placed on a WG+ card 141, in a manner similar to the placement of ISDN or coin circuits. The construction o~ the special service circuits are well ~nown to those skilled in the art. In this alternate embodiment, a special services unit is not required, since the special services circuit is deployed directly in BNU 110.
YI. U~es of the invention As an example of the use o~ the invention, it is possible to provision a BNU 110 which serves 8 residences 175 with two hex W G cards and achieve 150 penetration ~or W G services by supporting 12 W G
circuits, and later replace one of the W G cards with hex W G+ card, thus supporting ll W G circuits and one coin or ISDN circuit. Similarly, both hex WG cards can be replaced with two WG+ cards to support 10 WG
lines and 2 coin/ISDN lines or 1 coin and l ISDN line.
As an example of the use of the invention for the delivery of special services, a BNU 110 could be located in a residential area which contains a small business which requires a lottery circuit, which is a special service circuit. The BNU 110 could be provisioned with one hex WG card and one T1 hybrid card, and a special services unit could be deployed in the business or outside the business. A lottery circuit card would be placed in the special services unit, and the business would have the appropriate CPE
for lottery services. In this way a special lottery circuit card does not need to be deployed in the BNU.
Although this invention has been illustrated by reference to specific embodiments, it will be apparent ~5 to those skilled in the art that various changes and modifications may be made which clearly fall within the scope of the invention. The goal of the invention as an apparatus for providing a mixture of WG, coin, ISDN, or special services remains the same however. The invention is intended to be protected broadly within the spirit and scope of the appended claims.
Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein.
0 3 1 93.75% 6.25%
2 2 87 50% 12.50%
1 3 81.25% 18.75%
1 1 1 l112 50~ 12.50%
2 1 1106 . 25%18 75.
2 2137 50 12.50 2 1 1118.75 6 . 25~
1 1 2 118 75 6 . 25%
3 1106 . 25 6.25%
1 3118.75 18.75~
3 1 93.75 18.75%
1 3 131.25 6.25~
2 2 112 50 12.50%
4 75.00 25 00%
4125.00 25 00%
1 3 131 25 18.75~
1 3112 50 25 00%
3 1 143.75 6 . 25%
3 187.50 25.00%
III. Universal Voice Grade circuit The W G card 140 illustrated in FIGS. 2 and 3 provides POTs service to a number of residences 175 served by a BNU 110, and can provide this service through a Loop Start or Ground Start line/trunk interface. Typically, 6 ~ubscriber voice circuits (POTs lines) are served from a W G card 140. Referring W097/29585 PCT~S97/01245 to FIG . 2 the WG card 140 contains three dual line WG
circuits 812 such as the one illustrated in FIG. 3.
WG card connectors 860 allow connection of the WG card to backplane interconnects 808 which provide connectivity to the BNCC 800. The backplane interconnectg 808 provides connections to a number of signals including data buses which contain telecommunications data for subscribers as well as control information from the BDT 100 or the BNCC 800, and power and ground for the WG card itself.
Referring again to FIG. 3, the WG card contains a common control bus signal 882 which connects a Telephony Inter~ace Unit Application Specific Integrated Circuit (TIUA) 880 to BNCC 800.
TIUA 880 provides the time division multiplexing functions, state machine functions, and general control functions for the generation o~ a voice signals in conjunction with the other components of WG circuit 812.
An Electrically Erasable Programmable Read Only Memory (EEPROM) 886 is used in conjunction with TIUA 880 for the storage of operational data required when WG
card 140 is initially powered.
In addition to TIUA 880, each WG card 140 also includes a microcontroller and SRAM. These are indicated respectively by re~erence characters 884 and 887. Microcontroller 884 may be implemented using WO 97/29~i85 PCT/US97/01245 generally available products such as ~or example a Motorola 68HCllD3, and a suitable design choice for SRAM 887 is a 32K x 8 SRAM. A suitable SRAM for this purpose lS an Integrated Devices Technology SRAM
denoted IDT 712565A. Of course other manufacturer's devices having the indicated source capacity may also be used as a substitute.
A ringing generator 890 is included on the WG
card 140, which is capable of providing 40 V RMS into a 5 ringing equivalent (REN) load. Ringing generator 890 is controlled by a digital pulse train 892 ~rom TIUA
880, and receives a -130 V signal 894. The output o~
the ringing generator is ringing voltage 896.
A Pulse Code Modulated (PCM) bus 883 and serial bus 885 transfer signals to and ~rom TIUA 880 to subscriber line audio circuits. A single component known as a dual audio line subscriber audio circuit is used to provide a first audio line subscriber audio circuit 900 and a second subscriber line audio circuit 902 in dual line WG circuit 812 The Advanced Micro Devices' product denoted AM79C031, known by its trademarked name as DSLAC~ is a suitable design choice.
When used herein, the term DSLAC~ re~ers generically to a dual subscriber line audio circuit. An alternate design choice for a dual audio line subscriber audio circuit is the Siemens SiCoFi device.
The DSLAC~s are connected to a Subscriber Line CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 Interface Circuit (SLIC) 906. There are two SLICs 906 in each dual line W G circuit 812. In addition to generating the voice circuit interface for basic telephone service, each SLIC also performs loop sense and ring trip detection, tip and ring polarity reversals, provides ring delay drivers and provides a battery switch function to allow two different battery voltages to be used. Subscriber line interface circuits 906 may be implemented utilizing commercially available devices such as the Advanced Micro Devices product denoted AM7949.
A solid state relay 91O is used in each subscriber circuit to allow the application of the ringing voltage 896 through a lOO Q ringing resistor 898, as well as for providing metallic test access from the test in bus 912 and test out bus 914 toward the communications channel formed by the WG circuit and toward the twisted pair drop cable 260. AT&T part number ATTL7583 is a suitable design choice for solid state relay 910.
A transient over-voltage protector 918 is used to protect the solid state relay 91O from excessive voltages. A suitable design choice for the transient over-voltage protector 918 is the Teccor P2103 200 V
Sidactor.
Protection resistor 920 consists of two resistors, one in series with the tip (T) line 266 and on in series with the ring (R) line 268 which together form CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 the twisted pair drop cable 260. The protection resistors serve to protect the WG circuit from overvoltages, in particular overvoltages due to lightning strikes. Thick ~ilm or wirewound ~usible protection resistors are typically used. A suitable design choice ~or a protection resistor in protection resistor 920 is a 50 Q thick film resistor on a ceramic substrate.
A gas tube or carbon block device at the premises is used in conjunction with the transient over-voltage protector 918 and protection resistor to provide over-voltage protection. Protection resistor 920 presents suf~icient resistance such that in the event o~ a lightning strike the voltage at the premises will -15 remain su~iciently high to activate the gas tube or carbon block in addition to activating transient over-voltage protector 918.
IV. Universal Voice Card + circuits A. WG/ISDN circuit The WG/ISDN circuit 814 is illustrated in FIG. 4.
The circuit can provide ISDN Basic Access using 3-DS0 or 4:1 multiplexing. The inter~ace to the subscriber is a U-inter~ace operating over two wires at a data rate of 160 kb/s ~ull duplex.
The PCM bus 883 interconnects the TIU ASIC 880 with the U transceiver 862. The U transceiver 862 WO 97/29585 PCT/US97/012'~5 provides basic ISDN Basic Access functionality as described in the American National Standards Institute T1.601-1991 specification. ~ suitable design choice for the U transceiver 862 is the Siemens ISDN
Echocancellation Circuit IEC-Q 2091.
The U transceiver 862 is connected to the 4-2 wire hybrid 864 which converts half duplex transmission to full duplex transmission at the U interface. The 4-2 wire hybrid 864 can be realized using resistors and capacitors or with a single IC such as the Pulse Engineering PE36005W single chip hybrid.
The 4-2 wire hybrid is connected to the transformer 865. A suitable design choice for the 4-2 wire hybrid is the Pulse Engineering PE-65575 line transformer.
The transformer 865 is connected to a solid state relay 910 which provides access for the test in bus 912 and test out bus 914. Switching in and out of ringing is not required in the ISDN application.
A transient over-voltage protector 918 is used to protect the solid state relay 910 from excessive voltages. A suitable design choice for the transient over-voltage protector 918 is the Teccor P2103 200 V
Sidactor.
Following the transient over-voltage protector 918 a Positive Temperature Coefficient (PTC) device 866 is used to protect the circuit from excessive currents.
CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 B. WG/coin circuit The WG/coin circuit 814 is illustrated in FIG. 5.
Operation of the WG/coin circuit 814 is similar to - that of the W G circuit 812 with the addition of coin check/control 872 which permits the application of the four coin voltages: +48V, 874; -48V, 876; +80V, 878;
and -80V, 879. These voltages are used to control the functions of coin collect, coin refund, coin presence check, and coin base amount check, and keypad disable.
10 The voltages 874, 876, 878 and 879 are applied via the solid state relay 910.
The requirements for coin signaling are described in detail in Section 4.6 of Bellcore specification TA-NWT-O009O9, entitled "Generic Requirements and Objectives for Fiber in the Loop Systems," Issue 2, December 1993. Circuits for meeting these signaling requirements are known by those skilled in the art.
V. Delivery of s~ecial services Because there is a re~uirement to provide special services in addition to POTs, coin, and ISDN lines, there is a need for a method and apparatus of delivering those services efficiently from the BNU 110.
FIG. 6 illustrates a method in which special services are delivered from BNU 110 by the use of a T1 hybrid card A610, which includes POTs circuits and one - T1 circuit. The T1 circuit is used to provide a T1 CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 signal containing 24 DS0's to a Special Service Unit-8 (SSU-8) A620, which has plug-in cards for special services. The special services are then provided using a telecommunications link A618 and appropriate Customer Premises Equipment (CPE) A630. By providing special services in this way it is not necessary to have special service cards resident in BNU 110.
Referring to FIG. 6, delivery of special services is accomplished by providing DS0 channels to BDT 100 either by means of a D4 signal A604 which contains up to 24 special services circuits, or by using a Central Office Terminal Channel Bank A600 which receives unbundled specials signals A602 and ~orms a DSl signal A601. Signals are transported to BNU 110 via optical 1~ fiber 200. Tl hybrid card A610 provides a Tl signal over a four-wire twisted pair loop A623 to a Special Service Unit-8 (SSU-8) A620. SSU-8 A620 accepts whatever type of special services card is needed to provide the special service. Telecommunications link A618 can be twisted pair, coaxial cable, or any other type of telecommunications link required ~or the special service.
The special service unit shown in FIG. 6 as SSU-8 A620 can be located inside of a building, or can be located outside on a telephone pole or in any other suitable location for network equipment. A number of existing channel banks can be used as special service CA 02244000 l998-09-03 WO 97~29!;85 PCT/US97/01245 unit, and the size o~ the special service unit can vary ~rom a two-card unit up to a 24 card unit. The construction of channel banks is well understood by - those skilled in the art.
In addition to providing special services, T1 hybrid card A610 contains four POTs circuits, and can provide POTs services to residences 175 using via twisted pair drop cable 260. In the residence 175 the in-home twisted pair cable connects the telephone 185 to the twisted pair drop cable 260.
FIG. 7 illustrates the T1 hybrid card A610 in ~urther detail, showing ~our POTs circuits, POTS1 A72Oa, POTS2 A72Ob, POTs3 A720c, and POTS4 A72Od. A
DS1 circuit A730 is present to transmit and receive the 15 T1 signal to and ~rom SSU-8 A620. The DS1 common daughter board A710 plugs into the mother board A709 and provides the inter~ace ~unction to the BNCC 800.
The DS1 common daughter board A710 contains a T1 ASIC
A818, T1 microprocessor A822, external T1 Static Random 20 Access Memory (T1 S~AM) A826, and T1 ~P SRAM A824. A
separate processor (microcontroller) is used ~or the T1 circuit ~unctions in order not to burden the microcontroller 824 which is used ~or POTs circuit functions.
The common POTs block A740 provides the functions common to all o~ the POTs circuits. Included in the common POTs block A740 are the microcontroller 884, CA 02244000 l998-09-03 W097129~85 PCT~S97/01245 SRAM 887 TIUA 880, EEPROM 886, and ringing generator 890 illustrated in FIG. 3.
The DS1 clrcuit A730 is comprised of the clock adapter A820, framer A816, and Line Interface Unit ~LIU) A814.
A block diagram of the entire T1 circuit is illustrated in further detail in FIG. 8. The receive pair A810 and transmit pair A812 which form the four-wire twisted pair loop A623 are connected to the ~ine Interface Unit (LIU) A814. A suitable design choice for the ~IU A814 is the Level One LXT350 short haul TltE1 Transceiver.
A ~ramer A816 per~orms the ~raming ~unctions on the received and transmitted signals. A suitable design choice for ~ramer A816 is the BT8360.
A clock adapter A820 is used to generate a 1. 544 MHz clock A823 ~rom the 4.096 MHz clock A821 which is present on the hybrid T1 card A610. A suitable design choice ~or the clock adapter is the Level One LXP604 Clock Adapter.
The Tl ASIC A818 is used to form the Tl signal ~rom the BNU payload. Tl ASIC A818 is connected to TIU
BUS 882 which is connected to BNCC 800 via backplane interconnects 808. The Tl ASIC A818 is responsible for interfacing to backplane interconnects 808 and provides the processor interface and address decoding.
TI ASIC A818 stores a 4 ~rame downstream signaling CA 02244000 l998-09-03 W097/29585 PCT~S97/01245 history and translates upstream and downstream signaling on a per DS0 basis.
External T1 Static Random Access Memory (T1 SRAM) A826 is utilized in conjunction with T1 ASIC A818 for storing 4 signaling ~rames required for signaling freeze conditions. The T1 SRAM A826 is also used for storing downloaded signaling translation tables. The processor loads the tables via a memory banking method, through T1 ASIC A818. A suitable design choice for the size of T1 SRAM A826 is 32K*8, although only a few hundred bytes of memory may be required in actual operation.
A microprocessor A822 is used to configure the various components on the T1 hybrid card A610. A
suitable design choice is a Motorola 68HCllD3 microprocessor running at 2MHz. The microprocessor A822 will download code from the BNCC 800 via the data-link. External ~P Static Random Access Memory (~P
SRAM) A824 is utilized for storage of program information. A suitable design choice for the size of the ~P SRAM A824 is a 128K*8 SRAM, although only 64K is addressable space. The microprocessor A822 performs any necessary alarm monitoring and performance monitoring functions required, along with initialization of the LIU A814, framer A816, and T1 SRAM A826.
In a preferred embodiment, four POTs circuits are WO 971~9585 PCT/US97/01245 placed on a T1 Hybrid Card with one T1 circuit. This is because 2 twisted wire pairs are used ~or T1 service, and there are 6 pairs available ~or each WG
card 140, W G+ card 141, or Tl hybrid card A610. In an alternate embodiment, 5 POTs circuits can be placed on a card with one Tl circuit. This alternate embodiment requires connections ~or an additional twisted pair In an alternate embodiment the special service circuits can be placed on a WG+ card 141, in a manner similar to the placement of ISDN or coin circuits. The construction o~ the special service circuits are well ~nown to those skilled in the art. In this alternate embodiment, a special services unit is not required, since the special services circuit is deployed directly in BNU 110.
YI. U~es of the invention As an example of the use o~ the invention, it is possible to provision a BNU 110 which serves 8 residences 175 with two hex W G cards and achieve 150 penetration ~or W G services by supporting 12 W G
circuits, and later replace one of the W G cards with hex W G+ card, thus supporting ll W G circuits and one coin or ISDN circuit. Similarly, both hex WG cards can be replaced with two WG+ cards to support 10 WG
lines and 2 coin/ISDN lines or 1 coin and l ISDN line.
As an example of the use of the invention for the delivery of special services, a BNU 110 could be located in a residential area which contains a small business which requires a lottery circuit, which is a special service circuit. The BNU 110 could be provisioned with one hex WG card and one T1 hybrid card, and a special services unit could be deployed in the business or outside the business. A lottery circuit card would be placed in the special services unit, and the business would have the appropriate CPE
for lottery services. In this way a special lottery circuit card does not need to be deployed in the BNU.
Although this invention has been illustrated by reference to specific embodiments, it will be apparent ~5 to those skilled in the art that various changes and modifications may be made which clearly fall within the scope of the invention. The goal of the invention as an apparatus for providing a mixture of WG, coin, ISDN, or special services remains the same however. The invention is intended to be protected broadly within the spirit and scope of the appended claims.
Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein.
Claims (27)
1. In a telecommunications system, an apparatus for providing telecommunications services comprising a channel unit containing subscriber circuits wherein said channel unit contains at least one integrated services digital network circuit and at least one voice circuit.
2. The apparatus described in claim 1 wherein one eighth to one quarter of said subscriber circuits are integrated service digital network circuits and the remainder of said subscriber circuits are voice circuits.
3. In a fiber-to-the-curb telecommunications system, an apparatus for providing telecommunications services comprising:
a) an optical network unit; and b) a channel unit inserted into said optical network unit, wherein said channel unit contains at least one integrated services digital network circuit and at least one voice circuit.
a) an optical network unit; and b) a channel unit inserted into said optical network unit, wherein said channel unit contains at least one integrated services digital network circuit and at least one voice circuit.
4. The apparatus described in claim 3 wherein said channel unit contains one integrated services digital network circuit and three voice circuits.
5. The apparatus described in claim 3 wherein said channel unit contains one integrated services digital network circuit and five voice circuits.
6. In a fiber-to-the-curb telecommunications system, an apparatus for providing telecommunications services comprising:
a) an optical network unit; and b) a channel unit inserted into said optical network unit, wherein said channel unit contains a coin circuit, a voice circuit, and a dual subscriber line audio processing circuit, wherein said coin circuits utilizes a first half of said dual subscriber line audio processing circuit and said voice circuit utilizes a second half of said dual subscriber line audio processing circuit.
a) an optical network unit; and b) a channel unit inserted into said optical network unit, wherein said channel unit contains a coin circuit, a voice circuit, and a dual subscriber line audio processing circuit, wherein said coin circuits utilizes a first half of said dual subscriber line audio processing circuit and said voice circuit utilizes a second half of said dual subscriber line audio processing circuit.
7. In a fiber-to-the-curb telecommunications system, a method for providing voice and integrated services digital network telecommunications services, said method comprising the steps of:
a) receiving a voice signal and an integrated services digital network signal at a host digital terminal;
b) transmitting said voice signal and said integrated services digital network signal from said host digital terminal to an optical network unit via a telecommunications link; and c) generating at least on voice service interface and at least one integrated services digital network service interface on a channel unit located in said optical network unit.
a) receiving a voice signal and an integrated services digital network signal at a host digital terminal;
b) transmitting said voice signal and said integrated services digital network signal from said host digital terminal to an optical network unit via a telecommunications link; and c) generating at least on voice service interface and at least one integrated services digital network service interface on a channel unit located in said optical network unit.
8. The method described in claim 7 wherein one integrated services digital network service interface and three voice service interfaces are generated on said channel unit.
9. The method described in claim 7 wherein one integrated services digital network service interface and five voice service interfaces are generated on said channel unit.
10. In a fiber-to-the-curb telecommunications system, an apparatus for providing voice and integrated services digital network telecommunications services, said apparatus comprising:
a) means for receiving a voice signal and an integrated services digital network signal at a host digital terminal;
b) means for transmitting said voice signal and said integrated services digital network signal from said host digital terminal to an optical network unit via a telecommunications link; and c) means for generating at least one voice service interface and at least one integrated services digital network service interface on a channel unit located in said optical network unit.
a) means for receiving a voice signal and an integrated services digital network signal at a host digital terminal;
b) means for transmitting said voice signal and said integrated services digital network signal from said host digital terminal to an optical network unit via a telecommunications link; and c) means for generating at least one voice service interface and at least one integrated services digital network service interface on a channel unit located in said optical network unit.
11. The apparatus described in claim 10 wherein said channel unit has one integrated services digital network service interface and three voice service interfaces.
12. The apparatus described in claim 10 wherein said channel unit has one integrated services digital network service interface and five voice service interfaces.
13. In a fiber-to-the-curb telecommunications system, a method for providing voice and coin phone telecommunications services, said method comprising the steps of:
a) receiving a voice signal and a coin phone service signal at a host digital terminal;
b) transmitting said voice signal and said coin phone service signal from said host digital terminal to an optical network unit via a telecommunications link;
and c) generating at least one voice service interface and at least one coin phone service interface on a channel unit located in said optical network unit.
a) receiving a voice signal and a coin phone service signal at a host digital terminal;
b) transmitting said voice signal and said coin phone service signal from said host digital terminal to an optical network unit via a telecommunications link;
and c) generating at least one voice service interface and at least one coin phone service interface on a channel unit located in said optical network unit.
14. The method described in claim 13 wherein one coin phone service interface and three voice service interfaces are generated on said channel unit.
15. The method described in claim 13 wherein one coin phone service interface and five voice service interfaces are generated on said channel unit.
16. In a fiber-to-the-curb telecommunications system, an apparatus for providing voice and coin phone telecommunications services, said apparatus comprising:
a) means for receiving a voice signal and an coin phone service signal at a host digital terminal;
b) means for transmitting said voice signal and said coin phone signal from said host digital terminal to an optical network unit via a telecommunications link; and c) means for generating at least one voice service interface and at least one coin phone service interface on a channel unit located in said optical network unit.
a) means for receiving a voice signal and an coin phone service signal at a host digital terminal;
b) means for transmitting said voice signal and said coin phone signal from said host digital terminal to an optical network unit via a telecommunications link; and c) means for generating at least one voice service interface and at least one coin phone service interface on a channel unit located in said optical network unit.
17. The apparatus described in claim 16 wherein said channel unit has one coin phone service interface and three voice service interfaces.
18. The apparatus described in claim 13 wherein said channel unit has one coin phone service interface and five voice service interfaces.
19. In a telecommunications system, an apparatus for providing telecommunications services comprising a channel unit containing subscriber circuits wherein said channel unit contains at least one T1 circuit and at least one voice circuit.
20. The apparatus described in claim 19 wherein one eighth to one quarter of said subscriber circuits are T1 circuits and the remainder of said subscriber circuits are voice circuits.
21. In a fiber-to-the-curb telecommunications system, an apparatus for providing telecommunications services comprising:
a) an optical network unit; and b) a channel unit inserted into said optical network unit, wherein said channel unit contains at least one T1 circuit and at least one voice circuit.
a) an optical network unit; and b) a channel unit inserted into said optical network unit, wherein said channel unit contains at least one T1 circuit and at least one voice circuit.
22. The apparatus described in claim 21 wherein said channel unit contains one T1 circuit and three voice circuits.
23. The apparatus described in claim 21 wherein said channel unit contains one T1 circuit and four voice circuits.
24. In a fiber-to-the-curb telecommunications system, a method for providing voice and special telecommunications services, said method comprising the steps of:
a) receiving a voice signal and a special services signal at a host digital terminal;
b) transmitting said voice signal and said special services signal from said host digital terminal to an optical network unit via a telecommunications link;
c) generating at least one voice service interface on a channel unit located in said optical network unit;
d) generating a T1 signal containing said special services signal on said channel unit;
e) transmitting said special services signal in said T1 signal from said channel unit in said optical network unit to a special services unit via a second telecommunications link;
f) receiving said special services signal at said special services unit; and g) generating a special services interface at said special services unit.
a) receiving a voice signal and a special services signal at a host digital terminal;
b) transmitting said voice signal and said special services signal from said host digital terminal to an optical network unit via a telecommunications link;
c) generating at least one voice service interface on a channel unit located in said optical network unit;
d) generating a T1 signal containing said special services signal on said channel unit;
e) transmitting said special services signal in said T1 signal from said channel unit in said optical network unit to a special services unit via a second telecommunications link;
f) receiving said special services signal at said special services unit; and g) generating a special services interface at said special services unit.
25. The method described in claim 24 wherein one T1 signal and three to seven voice service interfaces are generated on said channel unit.
26. In a fiber-to-the-curb telecommunications system, an apparatus for providing voice and special telecommunications services, said apparatus comprising:
a) means for receiving a voice signal and a special services signal at a host digital terminal;
b) means for transmitting said voice signal and said special services signal from said host digital terminal to an optical network unit via a telecommunications link;
c) means for generating at least one voice service interface on a channel unit located in said optical network unit;
d) means for generating a T1 signal containing said special services signal on said channel unit;
e) means for transmitting said special services signal in said T1 signal from said channel unit in said optical network unit to a special services unit via a second telecommunications link;
f) means for receiving said special services signal at said special services unit; and g) means for generating a special services interface at said special services unit.
a) means for receiving a voice signal and a special services signal at a host digital terminal;
b) means for transmitting said voice signal and said special services signal from said host digital terminal to an optical network unit via a telecommunications link;
c) means for generating at least one voice service interface on a channel unit located in said optical network unit;
d) means for generating a T1 signal containing said special services signal on said channel unit;
e) means for transmitting said special services signal in said T1 signal from said channel unit in said optical network unit to a special services unit via a second telecommunications link;
f) means for receiving said special services signal at said special services unit; and g) means for generating a special services interface at said special services unit.
27. The apparatus described in claim 26 wherein said channel unit has means for generation of one T1 signal and three to seven voice service interfaces.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US1124296P | 1996-02-06 | 1996-02-06 | |
| US60/011,242 | 1996-02-06 | ||
| US79527197A | 1997-02-04 | 1997-02-04 | |
| US08/795,271 | 1997-02-04 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2244000A1 true CA2244000A1 (en) | 1997-08-14 |
Family
ID=26682155
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2244000 Abandoned CA2244000A1 (en) | 1996-02-06 | 1997-02-05 | Line cards for uvg, coin, isdn, and special services |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU1840697A (en) |
| CA (1) | CA2244000A1 (en) |
| WO (1) | WO1997029585A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6362908B1 (en) * | 1998-12-02 | 2002-03-26 | Marconi Communications, Inc. | Multi-service adaptable optical network unit |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4998274A (en) * | 1989-12-06 | 1991-03-05 | Bell Communications Research, Inc. | ISDN dual bus extension phone system |
| JPH05145681A (en) * | 1991-11-18 | 1993-06-11 | Matsushita Graphic Commun Syst Inc | Picture communication equipment |
| US5305312A (en) * | 1992-02-07 | 1994-04-19 | At&T Bell Laboratories | Apparatus for interfacing analog telephones and digital data terminals to an ISDN line |
| JP2571025B2 (en) * | 1994-10-13 | 1997-01-16 | 日本電気株式会社 | Optical termination node in the network |
-
1997
- 1997-02-05 CA CA 2244000 patent/CA2244000A1/en not_active Abandoned
- 1997-02-05 AU AU18406/97A patent/AU1840697A/en not_active Abandoned
- 1997-02-05 WO PCT/US1997/001245 patent/WO1997029585A1/en active Application Filing
Also Published As
| Publication number | Publication date |
|---|---|
| WO1997029585A1 (en) | 1997-08-14 |
| AU1840697A (en) | 1997-08-28 |
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