Transmission of broadband signals to subscribers using a telecom

Details Transmission of broadband signals to subscribers using a telecom Transmission of broadband signals to subscribers using a telecom

1992-06-01

1994-11-08

Chan, Wing F.

Telephonic communications

Telephone line or system combined with diverse electrical...

379 93, 455 31, H04M 1100

Patent

active

053634322

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

The present invention relates to a method and devices for transmission of broadband electrical signals, for example data and/or video, to a subscriber, particularly a subscriber who has a pre-installed telephone cable. The invention can avoid the need for installation of further drop cables (generally coaxial cables), dedicated to the new data or video service.
As communications technology advances, subscribers are reguesting services in addition to simple telephone service. For example, there is a demand for video and data by cable which requires a high band width for transmission. In this specification any bandwidth greater than that for simple telephone operation (voice band, generally about 4 KHz alalogue amplitude modulated and 64 KHz digital) preferably greater than that for 2,3,4,5,10 or 20 combined public switched telephone signals is referred to as broadband, and includes but is not limited to data and video. In particular, we are concerned with RF, VHF, and UHF signals, preferably of frequency greater than 20, more preferably greater than 30, especially greater than 40 KHz analogue (AM) or greater than 200,300 or 400 KHz digital. In practice we are likely to be concerned with values greater than 30 or 40 MHz, particularly from 47-862 MHz. The invention may also be considered useful for signals having a bandwidth of at least 0.0001, 0.001 or 0.01 times that of NTSC format video.
For some years now broadband signals have been transmitted electrically by coaxial cable. In many installations part of the network is active, which means that amplifiers are provided every few kilometers, and part of the network, namely the drops to individual subscribers running from so-called splitter boxes, are passive. If cable television (CATV), for example, is to be supplied to a subscriber the public right of way and the subscribers garden have to be dug-up and a new, coaxial, line installed in the ground. This is of course very expensive.
We have now discovered that installation of a new cable can be avoided and ordinary telephone cables used instead, particularly pre-installed cables already serving the subscriber.


SUMMARY OF THE INVENTION

Thus, the invention provides a method of transmitting a broadband electrical signal (such as data or video and particularly RF, VHF or UHF signals) to a subscriber by means of a telecommunications cable, preferably a telephone cable particularly a drop cable, preferably a preinstalled cable, the telecommunications cable comprising at least one pair of electrical conductors surrounded by an electrical shield, which method comprises applying the broadband signal between (a) the shield and (b) at least one of the conductors of the pair. All of the conductors within the shield are preferably provided in pairs, preferably twisted pairs, and the cable preferably is not of the coaxial type.
This method will be particularly attractive where the telephone cable (or other telecommunications cable) is preinstalled and where it has surplus capacity, for example where a cable having at least two pairs of conductors supplies a subscriber who requires only a single telephone line. Telephone cables to subscribers (often called drop wires or drop cables) often contain 6,10,20 or 30 pairs of conductors and there will frequently be spare pairs not employed for the telephone service. In this case the telephone service and the broadband service can make use of different pairs.
The invention can, nonetheless, be used where this surplus capacity is not present. This can be done, for example, by transforming the telephone signal into a high frequency signal and multiplexing that signal with the new broadband signal, and transmitting the combined signal in the way defined above. The signals would then be separated at the subscriber's premises. An alternative would be to retain the telephone signal at voice band frequency and apply the broadband signal on top of it at higher frequency. Again, some means of separation would be provided at the subscriber's premises.
The pre

REFERENCES:
patent: 4054910 (1977-10-01), Chou et al.
patent: 4135202 (1979-01-01), Cutler
patent: 4485400 (1984-11-01), Lemelson et al.
patent: 4578702 (1986-03-01), Campbell, III
patent: 4648682 (1987-03-01), Tubbs
patent: 4768854 (1988-09-01), Campbell et al.
patent: 4860343 (1989-08-01), Zetema, Jr.
patent: 4868565 (1989-09-01), Mettes et al.
patent: 4885747 (1989-12-01), Foglia
patent: 4891694 (1990-01-01), Way
patent: 5010399 (1991-04-01), Goodman et al.
patent: 5089886 (1992-02-01), Grandmougin

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