CA2444418C

CA2444418C - Telecommunications system and subscriber equipment therefor

Info

Publication number: CA2444418C
Application number: CA002444418A
Authority: CA
Inventors: Richard Marion Czerwiec; Joseph E. Sutherland; Geert Arthur Edith Van Wonterghem; Marlin V. Simmering; Eduard Christian Maria Boeykens; Chris Van Der Auwera; Peter Alain Richard Van Rompu; Kurt Pynaert; Daniel Alois Cornelius Verly; Gilbert Alfons Francoise Van Campenhout; Richard Haywood Bailey; Robert Nicolas Louis Peschi; Dirk Marcel Juliette Van Aken; Emmanuel Frans Borowski; Peter Paul Frans Reusens; Herman Leo Rosalia Verbueken; Frank Rychebusch; Keon Ambroise Godelieve De Wulf; Peter Mathijs Leonard Schepers
Original assignee: Alcatel SA
Current assignee: Alcatel Lucent SAS
Priority date: 1997-07-10
Filing date: 1998-06-10
Publication date: 2007-01-09
Anticipated expiration: 2018-06-10
Also published as: CA2444239A1; CA2444419C; CA2444236A1; CA2444420C; CA2444239C; CA2444420A1; CA2444418A1; CA2444231A1; CA2444419A1; CA2444236C

Abstract

An architecture, as well as various components, of an asynchronous transfer mode (ATM) subscriber access multiplexer (ASAM) system can be implemented using an xDSL (x-Digital Subscriber Line) using DMT (Discrete Multitone) or CAP (Carrierless Amplitude Phase Modulation) between a plurality of subscribers and a corresponding plurality of line termination equipment in a shelf that also includes network termination equipment for connection to an ATM network. The line termination and network termination equipment are interconnected by a bus internal to the shelf for providing subscriber access. Separate lowpass filters are provided at each end of a twisted wire pair between the shelf and each subscriber equipment. A shelf can be used as a hub for connecting to a remote shelf that includes the line termination equipment for connection to subscribers.
Although the internal bus of the shelf is shown in a nonredundant embodiment, an increased level of equipment protection can be provided by placing one half of a redundant equipment pair in one shelf and the other half in the other shelf and sharing network termination equipment between such shelves.

Claims

WHAT IS CLAIMED IS:

1. A telecommunications system, comprising:
subscriber equipment, and provider equipment, wherein the subscriber equipment comprises:
a downstream end low pass filter (42) for use at a subscriber's premises (54), responsive to a telephony signal (50) occupying a baseband position in a frequency division multiplexed signal (36) also having a broadband signal (58) occupying a position above baseband, for only providing said telephony signal for use in voice communications between said subscriber's premises and a public switched telephone network (PSTN); and a digital subscriber line modem (72) for use at the subscriber's premises, responsive to said frequency division multiplexed signal for providing said broadband signal for use in digital communications between said subscriber's premises and a packet network; and wherein the provider equipment comprises:
a shelf (34), responsive to said telephony signal (50) and to said broadband signal (58), for providing said frequency division multiplexed signal (36).

2. The telecommunications system of claim 1, wherein said shelf comprises:
a network termination (NT) card (12a) for connection to said packet network;
a plurality of line termination (LT) cards (14) for connection to said NT card by means of a backplane bus (78) of said shelf; and a plurality of upstream end lowpass filter (LPF) cards (24) each for connection to said PSTN;

wherein each upstream LPF card is for connection to a corresponding LT card for joining a corresponding telephony signal and a corresponding broadband signal at an upstream end of a twisted copper pair (36), wherein said telecommunications system further comprises a plurality of subscriber equipment each comprising a downstream end lowpass filter (42) and a digital subscriber line modem (72), each subscriber equipment for connection to a corresponding upstream end LPF card and LT card at a downstream end of a corresponding twisted copper pair.

3. The telecommunications system of claim 2, wherein said plurality of upstream end LPF cards are for insertion in slots of said at least one shelf, said slots arranged adjacent corresponding LT card slots of said shelf.

4. The telecommunications system of claim 3, further comprising a splitter shelf separate from said shelf (34) wherein one or more of said plurality of upstream end LPF cards are insertable in slots of said splitter shelf instead of said slots of said at least one shelf.

5. The telecommunications system of claim 1, wherein said broadband signal is a digital subscriber line signal.

6. The telecommunications system of claim 5, wherein said digital subscriber line signal is an asymmetrical digital subscriber line signal.

7. The telecommunications system of claim 6, wherein said asymmetrical digital subscriber line signal utilizes discrete multitone (DMT) for modulation.

8. The telecommunications system of claim 1, wherein said shelf is useable in a remote configuration as a remote shelf for connection to said packet network via another shelf used as a hub shelf part of said provider equipment wherein said hub shelf is useable for connecting said packet network to other remote shelves as well as directly to subscriber premises.

9. The telecommunications system of claim 8, wherein said provider equipment further comprises a rack for housing said hub shelf among a plurality of shelves interconnected via a common data and control bus.

10. The telecommunications system of claim 9, wherein said remote shelf is for connection to said packet network via said hub shelf or, alternatively, via a backup shelf of said rack.

11. The telecommunications system of claim 1, further comprising a plurality of racks each for housing at least one shelf for connection to a plurality of corresponding subscriber equipment.

12. The telecommunications system of claim 11, wherein said racks are for installation at different geographic locales.

13. Subscriber equipment for use in a telecommunications system having a shelf for connection both to a telephone network and to a broadband network and having a plurality of subscriber lines for connection to subscriber equipment at a plurality of subscriber premises, each subscriber equipment comprising:
a lowpass filter (42) for use at a subscriber's premises (54), responsive to a telephony signal (50, 52) occupying a baseband position in a frequency division multiplexed signal (36) also having a broadband signal (58, 74) occupying a position above baseband, for only providing said telephony signal between said lowpass filter (42) and a subscriber's telephone (56) for use in voice communications between said subscriber's premises and said telephone network; and a digital subscriber line modem (72) for use at the subscriber's premises, for connection to said frequency division multiplexed signal for only providing said broadband signal between said digital subscriber line modem (72) and a subscriber's data terminal (76) for use in digital communications between said subscriber's premises and said broadband network.

14. The subscriber equipment of claim 13, wherein said broadband signal (58) is transported in an asynchronous transfer mode (ATM) format.

15. The subscriber equipment of claim 13, wherein said frequency division multiplexed signal (36) is provided on a twisted wire pair connected between said shelf (34) and a downstream end node (68) at a subscriber end, said downstream node (68) for providing in a downstream direction said frequency division multiplexed signal to said lowpass filter (42) and said digital subscriber line modem (72) for splitting said telephony signal and said broadband signal, wherein said shelf includes an upstream end node (66) for joining in said downstream direction said telephony signal and said broadband signal to form said frequency division multiplexed signal.

16. The subscriber equipment of claim 13, wherein said downstream end lowpass filter (42) and said digital subscriber line modem (72) are connected to a downstream end node (68) which is in turn connected to an upstream end node (66) at said shelf (34) by a twisted wire pair, wherein said shelf includes a lowpass filter (40) and a highpass filter (38) connected to said upstream end node (66), wherein said highpass filter (38) is connected to said broadband signal (58) and wherein said lowpass filter (40) is connected to said telephony signal (50).

17. The subscriber equipment of claim 13, wherein said shelf includes an upstream end lowpass filter (40) and an upstream end highpass filter (38) both connected to said upstream end node (66), wherein said frequency division multiplexed signal (36) includes upstream signals including an upstream telephony signal occupying said baseband position and an upstream broadband signal occupying said position above baseband, and wherein said upstream end lowpass filter (40) is responsive to said upstream signals for only providing said upstream telephony signal upstream and wherein said upstream end highpass filter (38) is responsive to said upstream signals for only providing said upstream broadband signal.