CA1220848A - Wideband cable network - Google Patents
Wideband cable networkInfo
- Publication number
- CA1220848A CA1220848A CA000446739A CA446739A CA1220848A CA 1220848 A CA1220848 A CA 1220848A CA 000446739 A CA000446739 A CA 000446739A CA 446739 A CA446739 A CA 446739A CA 1220848 A CA1220848 A CA 1220848A
- Authority
- CA
- Canada
- Prior art keywords
- wideband
- network according
- switch
- interactive network
- optical fibre
- 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.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N7/00—Television systems
- H04N7/16—Analogue secrecy systems; Analogue subscription systems
- H04N7/173—Analogue secrecy systems; Analogue subscription systems with two-way working, e.g. subscriber sending a programme selection signal
- H04N7/17345—Control of the passage of the selected programme
- H04N7/17354—Control of the passage of the selected programme in an intermediate station common to a plurality of user terminals
Abstract
Abstract of the Disclosure An interactive wideband cable network has a central service position which can supply a plurality of simultaneous wideband services. At least one optical fibre is connected to the central service position and has at least one passive optical tapping point. At least two wideband switches are connected to the tapped optical fibre, and between the central service position and each wideband switch at least one additional optical fibre associated only with that switch.
Description
~;~2~
WIDEBAND CABLE NETWORK
Thls invention relates to a cable network which can provlde ~ideband services, e.g. a plurality of television and/or video channels, and which is lnteractive, i.e.
lnformatlon and data can pa~s in both dlrections.
The ma~orlty of cable televislon ~ervices are based on '-tree-and-branch~ topology, that is, chlannel~ are arrangefl in a frequency division multiplex and are broadca~t to subscribers by a broadband coa~ial cablej ln this context 'broadband-' means a bandwidth of at lea~t 450 MHz. Each ~ubscriber tapH the frequency dlvlælon multlplex ~ignal from the cable and selects a progr~mme by a set-top tuner. At each c~ble tap a signal 10~8 occurs, and the cable i8 also 1O8BY; and the su~med 1088 is ~ade up by the provlsion of ampliflers ln the cable. All customeru can recelve any part of the signal on the cable, and wlth this ~imple arrangement ~he provlaion of a special service at a dlfferential charging rate i8 impossible.
To glve selected cu~to~er~ a speclal servlce a scrambled signnl 18 often provlded, the customer's receivln~ aet contalns a descrambler, but scrambllng technlques are known, descramblers are easily available, and the security of the service is low. In the latest technlque~, addressable descrsmblers are used;
Further problems wlth tree-and-branch topology occur when an interactive servlce 18 requlred;
1 to allow the cus~omer to communicate with the service supplier at the central service polnt, the slgnal in the reveræe direction along the coaxial csble Must bypass all of the amplifiers;
WIDEBAND CABLE NETWORK
Thls invention relates to a cable network which can provlde ~ideband services, e.g. a plurality of television and/or video channels, and which is lnteractive, i.e.
lnformatlon and data can pa~s in both dlrections.
The ma~orlty of cable televislon ~ervices are based on '-tree-and-branch~ topology, that is, chlannel~ are arrangefl in a frequency division multiplex and are broadca~t to subscribers by a broadband coa~ial cablej ln this context 'broadband-' means a bandwidth of at lea~t 450 MHz. Each ~ubscriber tapH the frequency dlvlælon multlplex ~ignal from the cable and selects a progr~mme by a set-top tuner. At each c~ble tap a signal 10~8 occurs, and the cable i8 also 1O8BY; and the su~med 1088 is ~ade up by the provlsion of ampliflers ln the cable. All customeru can recelve any part of the signal on the cable, and wlth this ~imple arrangement ~he provlaion of a special service at a dlfferential charging rate i8 impossible.
To glve selected cu~to~er~ a speclal servlce a scrambled signnl 18 often provlded, the customer's receivln~ aet contalns a descrambler, but scrambllng technlques are known, descramblers are easily available, and the security of the service is low. In the latest technlque~, addressable descrsmblers are used;
Further problems wlth tree-and-branch topology occur when an interactive servlce 18 requlred;
1 to allow the cus~omer to communicate with the service supplier at the central service polnt, the slgnal in the reveræe direction along the coaxial csble Must bypass all of the amplifiers;
2 esch return path is a noi6e source, and this noi6e can llmit the number of cu6tomers who can be provided ~P,~
with an interactive facility;
with an interactive facility;
3 to cater ~or a large number of customers and because there is only limited return path capacity a polling system is o~ten used in the narrow band interactive signal, so that the response time is lony.
In a different system, an indiviau~l connection is made by optical fibre between a major switching point and each customer, ie a swi~ched-star topology is used; such a system was described at FOCUS 82 in Los Angeles, September l9B2 by John Fox (one of the present inventors) in a paper entitled "The Fibrevision Trial at Milton Keynes"; the major switching poin-t is located at a distance from the customers in a separate building, and from that building a separa-te optical fibre link is provided to each customer;
op-tical fibre links are at presen-t extremely expensive, thus the system is feasible only over very short distances.
It is an object of the present inven-tion to provide a cable network which allows a range of interactive services which is much wider than has previously been possible. The network is wldeband, i.e. it is capable o~ supplying moving images, such as television or video images on a raster screen.
Accordlng to one aspect of -the invention, there is provided an interactive wideband cable network co~prising:-a central service position which can supply a plurality of simultaneous fixed-time wideband services and at least one on-demand wideband service; at least one optical fibre con-nected to the central service position and having at least one passive optical tapping poin-t; a-t least -two wideband switches connected to the or each a-t least one tapped opti-cal fibre; a plurality of wideband service receiving units connected -to each wideband switch; each connec-tion being made through individual wideband connections all of which have a both-way transmission capability; and at least one additional op-tical fibre connected between -the cen-tral service posi-tion and each wideband switch ancl associa-ted only with that switch; whereby each wideband service receiving unit can receive simultaneously a plurality oE wideband ~22~8 services from the central service position, said plurality comprising at least one fixed-time wideband service received from the central service position -through the a-t least one tapped optical fibre and a-t leas~ one on-demand wideband service requested to the cen-tral service posi-tion through the at least one additional op-tical fibre associated only wi-th the wideband switch to which the requesting wideband service receiving unit is connected Another aspect of the invention provides a cable for use in an interactive wideband cable network comprising:-at least one optical fibre having at least one passive optical tapping point; and a-t least one additional optical fibre.
A further aspect of the invention provides a method of providing interactive wideband services comprises transmitting a plurality of simul-taneous fixed-time wideband services from a cen-tral service position to a plurality of wideband switches through at least one passively tapped op-tical fibre; receiving a request signal from any wideband switch through at least one additional optical fibre associated only with one wideband switch; and in response to the request signal providing at least one on-demand wide-band signal through an optical fibre associated with the wideband switch which originated the request.
Usually each wideband switch is connec-ted to a plurality of wideband service receiving units through indi-vidual wideband connections, each having a both-way trans-mission capability. The invention will now be described by way of example only with reference to the accompanying draw-ings in which -Figure 1 illustrates the topology of one form of cable network according to the invention;
Figure 2 illustrates the simultaneous services provided through the cable network of Figure l;
Figure 3 illustrates schema-tically a modified wide-band switching point;
- 3a -Figure 4 illustrates a tapped op-tical fibre layout;
and Figure 5 illustrates a variation of the cable net-work topology.
Figure 1 shows a central service poin-t or head-end 10 from which wideband services are supplied and which can receive and respond to requests from customers. The head-end 10 is connected by an optical fibre cable 12 to three wideband switching points (WSP) 14, 16, 18. There are two separate connections through the cable 12 to each WSP; a single services-supply optical fibre 2Q is ~apped by optical taps 22, 24 to give a connection to each WSP in tree-and-branch topology; the second connection is formed by a dedica-ted optical fibre pair from each WSP to -the head-end, for example WSP 14 is connected to head-end 10 by dedicated optical fibre pair 26; WSP lb is connected by fibre pair 28, and WSP 18 is connected by fibre pair 30; the optical fibre pairs 26, 28, 3Q are arranged in star topology be-tween the head-end 10 and the respective WSP 14, 16, 18.
Each WSP 14, 16, 18 is connected by wideband connections to several customer~; the connections may be ~y optlcal fibre pairs or by coaxial cables. For WSP 16 the connectlons are indicated by the double-hesded arrows 32, and flve customers only are shown, although in practice there will be a greater number; each connection is two-way. One ~uch connectlon is illustrated in detail;
the WSP 16 1B connected to a customer'~ ter~lnation unlt 34 by coaxial cable; the servlces provided are shown schematically a6 two televislon recelvlng ~et~ 36, 38 and ~ frequency-~odulated radlo recelving set 40; the termination unlt 34 18 also connected to A keypad 42 by whlch the customer co~ounicates wlth head-end 10, and addltional two-way eervlces ~re lndicated by the double-hesded ~rrow 44. The service~ ~ill be described in detall below~
The custo~er'c termlnation unlt 34 receives ~IF
signalH nnd converts them to U~F signsls to feed to the two con-ventional -television receiving sets 36 and 38; the unit 34 is connected to the two television sets 36 and 38 and to the radio set 40 by conventional UHF wiring.
Although o~ly one optical fibre cable 12 fro~ the head-end 10 is ehown in Figure 1, in practlce several or many ~eparaee cables of thls type wlll be provlded, a~
lnd~cated by the arrows 46. Further,the head-end is connected to the public switched telephone network PSTN
and p~cket switched service PSS of the telephone network through respectlve 6wltches 47, 49. The head-end 1~ also connected to local studios and to other signal source6.
Reference to Flgure 1 shows that the cable layout for thls interactlve ~ldeband servlce provi~ion is a novel, inventlve combination of a tree and-branch topology (optlcal fibre 20~, and star topology, (optical fibre pair3 26, 28, 30). The layout may be u~ed for either dlgital or analogue signals.
;~
, ~%~
Flgure 1 al60 illu6trates the connection of a ~aJor customer 48; a dedicated optical fibre pair 50 i8 provided in ttle cable allowing the maJor customer the full range of lnteractive wldeband service6 available without passage through A WSP such ~s 16. Thi~ flbre palr 1~
arranged ln star topology. Such an lndivid~al connectlon ls very secure.
Swi tc hi ng i n the WSP i 8 done a t baseband. The 8witch contalns a proce~sor whlch control~ channel lo selection on request from a subscriber.
Flgure 2 shows an example of the spectrum allocation ln the wideband link (i.e. the coaxial cable) between each cu~tomer ter~lnntlon unit, ~uch a8 34, and a WSP ~uch as 16. ~orking from hlgh to lo~ freque~cles, the pllot signal 18 located at about 120 MHz, with FM radlo between 88 and 108 MHz. The t~o television channels lie between 38 and 65 MHz, and another video channel band lles at 22 to 30 MHz. One or more vldeo channe~ may transmit ~ignals from a customer to the head-end 10. Data transfer and telephony cover ~he range 5 to 15 M~z, and the narro~
si~nalllng bandwldth occupies the lowest frequency range.
Other sig~als, ~uch ~s Dlrect Broadcast by Satellite, can be lncluded if requlred. There i8 ~pare cspaclty between 60 and 88 MHz.
In the optical flbre cable 12, the signalllng, data and telephony, and the return vldeo signals are cnrried by the optical fibre pair dedicated to a particular WSP, whlle the TV channels are carried to the WSP by the tapped optical fibre 20. The FM radio signal3 may be carried elther by tapped optical flbre 20 or by a dedicated fibre.
It 16 believed that thi6 is the first tlme thnt such a wlde range of simultaneous servi~es ha~ been available on a cable network.
While the range of slmultaneous services shown ln ~2~
Figure 2 is far greater than is currently available, the bandwidth demands ~re such that~ glven the present ~tate of the technology, one tapped optical fibre, such as flbre 20, can only carry four televlsion channels, especlally s when considering the po~lbility ln the near fu~ure of enhAnced transmi~sion ~tandards requiring a b~se bandwidth of 10 to 13 MHz ln~tead of the 8 ~1~ required for ~he ~uropean PAL tr~na~isslons. ~lgh deflnition televicion ~1th 1000 11neS 1B alBo env~g~d and ~ill need a b~ndwidth of about 30 ~H~ and l~oking even fureher nhead to dlglt~l TV an ~ve~ hlgher b~ndwidth wlll be needed. It i~ therefore expec~ed tb~e each ~SP will ~e provided ~ith ~. ~ore than one tspped cptlcal fibre and B typioal arr~nge~ene i~ ~ho~n in F1gure 3.
A WSP 52 is connected to each of flve optlcal flbres 54, 56, 58, 60, 62 by respecti~e optical taps 55, 57, 59b 61 and 63. The ~SP lc also connected ~o five dedlcaeed optlcal fibre~ 64~ 66, 68, 70 and 72. The tapped fibre~ and the dedic~ted flbre~ form p~rt of a csble 74 whlch al~o carrie~ a multipllclty of optlcal fibres 76 to 78, indicated ~chematically, whlch are dedicated to other WSPs, not lllustrated. The ~SP 52 1~
connec~ed to a plurality of customers by wldebsnd links of whlch five are chown schematically, reference 80.
If each tapped optical fibre carrles four televlslon channels, then each customer hag a choice of 20 channels. Of the five dedicated optlcal fibres to a ~SP, three (64, 66, 68) will provlde four televlslon or vldeo channels each of which are indivldually selectable by a customer, one fibre 70 carries F~ radio, and the fifth fibre 72 carrle6 four televislon channels from the WSP to the head-end; data and control signals are carried by a television channel.
The optical fibre connections illustrated in Figure // ~22~
3 can be provided to each of the WSPs 14r 16, 18 llluatrated in Figure 1. Flgure 3 18 me~el~ one of ~ny po~sible arran~ent~.
Xn Figure 1 the tapped optlc~l flbre 20 ia æhown ~lth two optic~l tap~ in serie~ giving three WSPs, 14~ 16, 18.
Many o~her ~rrangements are pos~lble; for exampl~ in Pigure 4, a slngle optical fibre ~2 ln a cable 84 from a head-end 86 18 opti~ally tapped three time~ ia 6eries to feed ~ ma~imum of el~ht ~SPs, 88 to 95, by u~e of ~even lO ~ptical taps 96 to 102 esch dividing the ~ignal power by v two. There i8 inevitably 80~e power lofis ln e~ch tap.
Any of the tapped optlc~l flbre~ 20 ~ Figu~e 1 or 54 etc in Figure 3 could be ~rranged ln thl~ way to feed a greater number of WSPs than illustrated in tho~e Figures.
15 ~ach ~SP, such a~ 889 would be connected to several customer~ a~ before, and would have one or more dedic~e~
optical fibre links such as 104.
The cable topology can be extended to cover a wlder geographical ~rea as sho~n ln Flgure 5. The custo~er 20 ter~inatlon unit lOo and WSP 108 with their wide~and connection 110 are ldentical ~o those lllu~trated in Figure 1, but there i8 ~n addltlonal node ln the ne~work;
the WSP 108 i3 connected to the head-end 112, through a hub ~lte 114. The topology of the cable connectlon 116 25 between the hub slte 114 and the ~SP 108 wlll be ldentical to that 3hown ln Flgure 1, or to one of it6 variations ln subsequent Flgures, and the cable 118 between the hub ~ite 114 and the super head-end 112 wlll be star connected.
Referring once more to Figure 1, numerlcal values will now be glven for some variables of the network, but the3e are entlrely by way of example and are in no sense limiting. At the head-end 10, the four televiRion channels wlll each be modulated on a carrler frequency, the carrler frequencles wlll be multlplexed, and the ~2~
mulLlple~ed signal i8 applled to modulate a narrow strlpe la~er source which operates at about 850 nanometres; the modulated optlcal signal 1~ tran~mitted by the optical fibre. The graded Index fibre 20 wlll have a 1088 of no more than 3.5 decibels per kllome~re wlth a bandwidth of 600 MHz per kllometre, and the distance between the head-end lO snd each WSP such as 16 will be Up to 5 kilometres. Each WSP will serve up to 300 cu~omers at a m~xlmum dlstance, i.e. a maximum length of coaxial cable, of 500 ~e~res when ~he ~axlmum frequ,ency iB 128a than lOO k~l2 ~nd one head-end ~ay serve up to lOOjOOO
customers.
When the network varlation illustrated ln Pigure 5 is ueed, the dlstsnce from ehe head-end 112 to the hub ~l~e 114 may be up to 30 kilometres ~using monomode fibre and a diferent wavelength) and the distance from the hub site 114 to the WSP 108 may be up to 5 kllometres.
Such spans of optical flbre cables can be achleved u0ing current technology without providlng repeaters.
Conveniently each WSP 18 located in an on-atreet cabinet, slmilar to a cabinet used for conventional telephone services, and each hub site can be colocated with a local telephone exchange.
Each of the servlces provided by the cable network of the present inventlon will be now be described FIXED TIME PROGRAMMES
The television programmes provided through the tapped optlcal fibre and FM radio will correspond to normal off-air televlsion channela, or to a conventlonal cable television service which may Include direct broadcast by 6atellite, and to conventional off-air radio. The customer has no control over the time at which signals are received, but he may, of course, record any fixed-time programme even while receiving and viewlng normally a second televlsion channel.
The provls10n of an interactlve network allows either free" dlstributlon or di~trlbutlon on a subscriptLon or pay-per-view bn0is; in the network according to the lnventlon, the 6ervice provided i8 flexlble, programme security i~ good~ and indlvldual accounting can be comprehenslve.
DATA AND TELEPHONY SERVIC~S
The conventlonal copper pair local telephony network already extends to data tranfimisalon at 64 Kbit/6, - but its upper limlt 18 likely to be reached ~ith the Integrated Servlces Digltal Network whlch i8 expected to extend, by the probable CCITT recommendatlon~ to 144 kbit/s. Business customers are expected to use hlgh blt-rate services by mean~ of thelr dedicated optical flbre llnks, and there i8 access at the hesd-end to packet switched servlces (i.e. a service in which addres.sed packets of data are transferred through a public swltched network) and integrated digltal services. Domestic and small customers wlll noe need such access, but low usage data servlces, such as required by the home computer market, can be covered by common use of a wldeband servlce.
Other services which can be offered are alarms and telemetry which can be easlly and cheaply lncorporated in the signalling data streams of the network.
VIDEO SERVICES
The bandwidth allocated in Figure 2 can be used in several ways; for example:
1 alphanumeric and photographic vldeotext services, in which the shared use of text generators in the WSP and picture generators in the head-end will minlmise the cost of providing a high bandwidth signal to a conventlonal television set, ln contrast to providing individual converters for ~2~
-- 1 o / use with ~ignal8 received over telephone circuit~. The lnteractive nature of the network according to the inventlon allows a wlde range o i.ndlvldual lnteractive service~ such a~
S home banklne, home ~hopping and mailbox;
2 a vldeo l~brary ~ervice can be provided, by ~hich ~inority-interest programmes c~n be provided at 8 tl~e ~elected by ~ cus~omer; an interac~lve mode 1~ poscible, e~ fa~t frame ~earch, repeat modec, frame hold, 810w motloD tramiml~cl~n, etc or recpon~e to programmed-le~r~ing tran8mi~10ns.
3 A video telephone ~ervice may al80 be provided.
In a different system, an indiviau~l connection is made by optical fibre between a major switching point and each customer, ie a swi~ched-star topology is used; such a system was described at FOCUS 82 in Los Angeles, September l9B2 by John Fox (one of the present inventors) in a paper entitled "The Fibrevision Trial at Milton Keynes"; the major switching poin-t is located at a distance from the customers in a separate building, and from that building a separa-te optical fibre link is provided to each customer;
op-tical fibre links are at presen-t extremely expensive, thus the system is feasible only over very short distances.
It is an object of the present inven-tion to provide a cable network which allows a range of interactive services which is much wider than has previously been possible. The network is wldeband, i.e. it is capable o~ supplying moving images, such as television or video images on a raster screen.
Accordlng to one aspect of -the invention, there is provided an interactive wideband cable network co~prising:-a central service position which can supply a plurality of simultaneous fixed-time wideband services and at least one on-demand wideband service; at least one optical fibre con-nected to the central service position and having at least one passive optical tapping poin-t; a-t least -two wideband switches connected to the or each a-t least one tapped opti-cal fibre; a plurality of wideband service receiving units connected -to each wideband switch; each connec-tion being made through individual wideband connections all of which have a both-way transmission capability; and at least one additional op-tical fibre connected between -the cen-tral service posi-tion and each wideband switch ancl associa-ted only with that switch; whereby each wideband service receiving unit can receive simultaneously a plurality oE wideband ~22~8 services from the central service position, said plurality comprising at least one fixed-time wideband service received from the central service position -through the a-t least one tapped optical fibre and a-t leas~ one on-demand wideband service requested to the cen-tral service posi-tion through the at least one additional op-tical fibre associated only wi-th the wideband switch to which the requesting wideband service receiving unit is connected Another aspect of the invention provides a cable for use in an interactive wideband cable network comprising:-at least one optical fibre having at least one passive optical tapping point; and a-t least one additional optical fibre.
A further aspect of the invention provides a method of providing interactive wideband services comprises transmitting a plurality of simul-taneous fixed-time wideband services from a cen-tral service position to a plurality of wideband switches through at least one passively tapped op-tical fibre; receiving a request signal from any wideband switch through at least one additional optical fibre associated only with one wideband switch; and in response to the request signal providing at least one on-demand wide-band signal through an optical fibre associated with the wideband switch which originated the request.
Usually each wideband switch is connec-ted to a plurality of wideband service receiving units through indi-vidual wideband connections, each having a both-way trans-mission capability. The invention will now be described by way of example only with reference to the accompanying draw-ings in which -Figure 1 illustrates the topology of one form of cable network according to the invention;
Figure 2 illustrates the simultaneous services provided through the cable network of Figure l;
Figure 3 illustrates schema-tically a modified wide-band switching point;
- 3a -Figure 4 illustrates a tapped op-tical fibre layout;
and Figure 5 illustrates a variation of the cable net-work topology.
Figure 1 shows a central service poin-t or head-end 10 from which wideband services are supplied and which can receive and respond to requests from customers. The head-end 10 is connected by an optical fibre cable 12 to three wideband switching points (WSP) 14, 16, 18. There are two separate connections through the cable 12 to each WSP; a single services-supply optical fibre 2Q is ~apped by optical taps 22, 24 to give a connection to each WSP in tree-and-branch topology; the second connection is formed by a dedica-ted optical fibre pair from each WSP to -the head-end, for example WSP 14 is connected to head-end 10 by dedicated optical fibre pair 26; WSP lb is connected by fibre pair 28, and WSP 18 is connected by fibre pair 30; the optical fibre pairs 26, 28, 3Q are arranged in star topology be-tween the head-end 10 and the respective WSP 14, 16, 18.
Each WSP 14, 16, 18 is connected by wideband connections to several customer~; the connections may be ~y optlcal fibre pairs or by coaxial cables. For WSP 16 the connectlons are indicated by the double-hesded arrows 32, and flve customers only are shown, although in practice there will be a greater number; each connection is two-way. One ~uch connectlon is illustrated in detail;
the WSP 16 1B connected to a customer'~ ter~lnation unlt 34 by coaxial cable; the servlces provided are shown schematically a6 two televislon recelvlng ~et~ 36, 38 and ~ frequency-~odulated radlo recelving set 40; the termination unlt 34 18 also connected to A keypad 42 by whlch the customer co~ounicates wlth head-end 10, and addltional two-way eervlces ~re lndicated by the double-hesded ~rrow 44. The service~ ~ill be described in detall below~
The custo~er'c termlnation unlt 34 receives ~IF
signalH nnd converts them to U~F signsls to feed to the two con-ventional -television receiving sets 36 and 38; the unit 34 is connected to the two television sets 36 and 38 and to the radio set 40 by conventional UHF wiring.
Although o~ly one optical fibre cable 12 fro~ the head-end 10 is ehown in Figure 1, in practlce several or many ~eparaee cables of thls type wlll be provlded, a~
lnd~cated by the arrows 46. Further,the head-end is connected to the public switched telephone network PSTN
and p~cket switched service PSS of the telephone network through respectlve 6wltches 47, 49. The head-end 1~ also connected to local studios and to other signal source6.
Reference to Flgure 1 shows that the cable layout for thls interactlve ~ldeband servlce provi~ion is a novel, inventlve combination of a tree and-branch topology (optlcal fibre 20~, and star topology, (optical fibre pair3 26, 28, 30). The layout may be u~ed for either dlgital or analogue signals.
;~
, ~%~
Flgure 1 al60 illu6trates the connection of a ~aJor customer 48; a dedicated optical fibre pair 50 i8 provided in ttle cable allowing the maJor customer the full range of lnteractive wldeband service6 available without passage through A WSP such ~s 16. Thi~ flbre palr 1~
arranged ln star topology. Such an lndivid~al connectlon ls very secure.
Swi tc hi ng i n the WSP i 8 done a t baseband. The 8witch contalns a proce~sor whlch control~ channel lo selection on request from a subscriber.
Flgure 2 shows an example of the spectrum allocation ln the wideband link (i.e. the coaxial cable) between each cu~tomer ter~lnntlon unit, ~uch a8 34, and a WSP ~uch as 16. ~orking from hlgh to lo~ freque~cles, the pllot signal 18 located at about 120 MHz, with FM radlo between 88 and 108 MHz. The t~o television channels lie between 38 and 65 MHz, and another video channel band lles at 22 to 30 MHz. One or more vldeo channe~ may transmit ~ignals from a customer to the head-end 10. Data transfer and telephony cover ~he range 5 to 15 M~z, and the narro~
si~nalllng bandwldth occupies the lowest frequency range.
Other sig~als, ~uch ~s Dlrect Broadcast by Satellite, can be lncluded if requlred. There i8 ~pare cspaclty between 60 and 88 MHz.
In the optical flbre cable 12, the signalllng, data and telephony, and the return vldeo signals are cnrried by the optical fibre pair dedicated to a particular WSP, whlle the TV channels are carried to the WSP by the tapped optical fibre 20. The FM radio signal3 may be carried elther by tapped optical flbre 20 or by a dedicated fibre.
It 16 believed that thi6 is the first tlme thnt such a wlde range of simultaneous servi~es ha~ been available on a cable network.
While the range of slmultaneous services shown ln ~2~
Figure 2 is far greater than is currently available, the bandwidth demands ~re such that~ glven the present ~tate of the technology, one tapped optical fibre, such as flbre 20, can only carry four televlsion channels, especlally s when considering the po~lbility ln the near fu~ure of enhAnced transmi~sion ~tandards requiring a b~se bandwidth of 10 to 13 MHz ln~tead of the 8 ~1~ required for ~he ~uropean PAL tr~na~isslons. ~lgh deflnition televicion ~1th 1000 11neS 1B alBo env~g~d and ~ill need a b~ndwidth of about 30 ~H~ and l~oking even fureher nhead to dlglt~l TV an ~ve~ hlgher b~ndwidth wlll be needed. It i~ therefore expec~ed tb~e each ~SP will ~e provided ~ith ~. ~ore than one tspped cptlcal fibre and B typioal arr~nge~ene i~ ~ho~n in F1gure 3.
A WSP 52 is connected to each of flve optlcal flbres 54, 56, 58, 60, 62 by respecti~e optical taps 55, 57, 59b 61 and 63. The ~SP lc also connected ~o five dedlcaeed optlcal fibre~ 64~ 66, 68, 70 and 72. The tapped fibre~ and the dedic~ted flbre~ form p~rt of a csble 74 whlch al~o carrie~ a multipllclty of optlcal fibres 76 to 78, indicated ~chematically, whlch are dedicated to other WSPs, not lllustrated. The ~SP 52 1~
connec~ed to a plurality of customers by wldebsnd links of whlch five are chown schematically, reference 80.
If each tapped optical fibre carrles four televlslon channels, then each customer hag a choice of 20 channels. Of the five dedicated optlcal fibres to a ~SP, three (64, 66, 68) will provlde four televlslon or vldeo channels each of which are indivldually selectable by a customer, one fibre 70 carries F~ radio, and the fifth fibre 72 carrle6 four televislon channels from the WSP to the head-end; data and control signals are carried by a television channel.
The optical fibre connections illustrated in Figure // ~22~
3 can be provided to each of the WSPs 14r 16, 18 llluatrated in Figure 1. Flgure 3 18 me~el~ one of ~ny po~sible arran~ent~.
Xn Figure 1 the tapped optlc~l flbre 20 ia æhown ~lth two optic~l tap~ in serie~ giving three WSPs, 14~ 16, 18.
Many o~her ~rrangements are pos~lble; for exampl~ in Pigure 4, a slngle optical fibre ~2 ln a cable 84 from a head-end 86 18 opti~ally tapped three time~ ia 6eries to feed ~ ma~imum of el~ht ~SPs, 88 to 95, by u~e of ~even lO ~ptical taps 96 to 102 esch dividing the ~ignal power by v two. There i8 inevitably 80~e power lofis ln e~ch tap.
Any of the tapped optlc~l flbre~ 20 ~ Figu~e 1 or 54 etc in Figure 3 could be ~rranged ln thl~ way to feed a greater number of WSPs than illustrated in tho~e Figures.
15 ~ach ~SP, such a~ 889 would be connected to several customer~ a~ before, and would have one or more dedic~e~
optical fibre links such as 104.
The cable topology can be extended to cover a wlder geographical ~rea as sho~n ln Flgure 5. The custo~er 20 ter~inatlon unit lOo and WSP 108 with their wide~and connection 110 are ldentical ~o those lllu~trated in Figure 1, but there i8 ~n addltlonal node ln the ne~work;
the WSP 108 i3 connected to the head-end 112, through a hub ~lte 114. The topology of the cable connectlon 116 25 between the hub slte 114 and the ~SP 108 wlll be ldentical to that 3hown ln Flgure 1, or to one of it6 variations ln subsequent Flgures, and the cable 118 between the hub ~ite 114 and the super head-end 112 wlll be star connected.
Referring once more to Figure 1, numerlcal values will now be glven for some variables of the network, but the3e are entlrely by way of example and are in no sense limiting. At the head-end 10, the four televiRion channels wlll each be modulated on a carrler frequency, the carrler frequencles wlll be multlplexed, and the ~2~
mulLlple~ed signal i8 applled to modulate a narrow strlpe la~er source which operates at about 850 nanometres; the modulated optlcal signal 1~ tran~mitted by the optical fibre. The graded Index fibre 20 wlll have a 1088 of no more than 3.5 decibels per kllome~re wlth a bandwidth of 600 MHz per kllometre, and the distance between the head-end lO snd each WSP such as 16 will be Up to 5 kilometres. Each WSP will serve up to 300 cu~omers at a m~xlmum dlstance, i.e. a maximum length of coaxial cable, of 500 ~e~res when ~he ~axlmum frequ,ency iB 128a than lOO k~l2 ~nd one head-end ~ay serve up to lOOjOOO
customers.
When the network varlation illustrated ln Pigure 5 is ueed, the dlstsnce from ehe head-end 112 to the hub ~l~e 114 may be up to 30 kilometres ~using monomode fibre and a diferent wavelength) and the distance from the hub site 114 to the WSP 108 may be up to 5 kllometres.
Such spans of optical flbre cables can be achleved u0ing current technology without providlng repeaters.
Conveniently each WSP 18 located in an on-atreet cabinet, slmilar to a cabinet used for conventional telephone services, and each hub site can be colocated with a local telephone exchange.
Each of the servlces provided by the cable network of the present inventlon will be now be described FIXED TIME PROGRAMMES
The television programmes provided through the tapped optlcal fibre and FM radio will correspond to normal off-air televlsion channela, or to a conventlonal cable television service which may Include direct broadcast by 6atellite, and to conventional off-air radio. The customer has no control over the time at which signals are received, but he may, of course, record any fixed-time programme even while receiving and viewlng normally a second televlsion channel.
The provls10n of an interactlve network allows either free" dlstributlon or di~trlbutlon on a subscriptLon or pay-per-view bn0is; in the network according to the lnventlon, the 6ervice provided i8 flexlble, programme security i~ good~ and indlvldual accounting can be comprehenslve.
DATA AND TELEPHONY SERVIC~S
The conventlonal copper pair local telephony network already extends to data tranfimisalon at 64 Kbit/6, - but its upper limlt 18 likely to be reached ~ith the Integrated Servlces Digltal Network whlch i8 expected to extend, by the probable CCITT recommendatlon~ to 144 kbit/s. Business customers are expected to use hlgh blt-rate services by mean~ of thelr dedicated optical flbre llnks, and there i8 access at the hesd-end to packet switched servlces (i.e. a service in which addres.sed packets of data are transferred through a public swltched network) and integrated digltal services. Domestic and small customers wlll noe need such access, but low usage data servlces, such as required by the home computer market, can be covered by common use of a wldeband servlce.
Other services which can be offered are alarms and telemetry which can be easlly and cheaply lncorporated in the signalling data streams of the network.
VIDEO SERVICES
The bandwidth allocated in Figure 2 can be used in several ways; for example:
1 alphanumeric and photographic vldeotext services, in which the shared use of text generators in the WSP and picture generators in the head-end will minlmise the cost of providing a high bandwidth signal to a conventlonal television set, ln contrast to providing individual converters for ~2~
-- 1 o / use with ~ignal8 received over telephone circuit~. The lnteractive nature of the network according to the inventlon allows a wlde range o i.ndlvldual lnteractive service~ such a~
S home banklne, home ~hopping and mailbox;
2 a vldeo l~brary ~ervice can be provided, by ~hich ~inority-interest programmes c~n be provided at 8 tl~e ~elected by ~ cus~omer; an interac~lve mode 1~ poscible, e~ fa~t frame ~earch, repeat modec, frame hold, 810w motloD tramiml~cl~n, etc or recpon~e to programmed-le~r~ing tran8mi~10ns.
3 A video telephone ~ervice may al80 be provided.
Claims (31)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An interactive wideband cable network comprising:-a central service position which can supply a plurality of simultaneous fixed-time wideband services and at least one on-demand wideband service;
at least one optical fibre connected to the central service position and having at least one passive optical tapping point;
at least two wideband switches connected to the or each at least one tapped optical fibre;
a plurality of wideband service receiving units connected to each wideband switch, each said connection being made through individual wideband connections all of which have a both-way transmission capability;
and at least one additional optical fibre con-nected between the central service position and each wide-band switch and associated only with that switch;
whereby each wideband service receiving unit can receive simultaneously a plurality of wideband services from the central service position, said plurality comprising at least one fixed-time wideband service received from the central service position through the at least one tapped optical fibre and at least one on-demand wideband service requested to the central service position through the at least one additional optical fibre associated only with the wideband switch to which the requesting wideband service receiving unit is connected.
at least one optical fibre connected to the central service position and having at least one passive optical tapping point;
at least two wideband switches connected to the or each at least one tapped optical fibre;
a plurality of wideband service receiving units connected to each wideband switch, each said connection being made through individual wideband connections all of which have a both-way transmission capability;
and at least one additional optical fibre con-nected between the central service position and each wide-band switch and associated only with that switch;
whereby each wideband service receiving unit can receive simultaneously a plurality of wideband services from the central service position, said plurality comprising at least one fixed-time wideband service received from the central service position through the at least one tapped optical fibre and at least one on-demand wideband service requested to the central service position through the at least one additional optical fibre associated only with the wideband switch to which the requesting wideband service receiving unit is connected.
2. An interactive wideband cable network according to claim 1, in which said at least one on-demand wideband service is received from the central service position through the at least one additional optional fibre associated only with the wideband switch to which the requesting wideband service receiving unit is connected.
3. An interactive network according to claim 1, in which the or each additional optical fibre is connected in the central service position to signal generating means capable of supplying at least one on-demand wideband service.
4. An interactive network according to claim 3 in which the at least one on-demand wideband service includes at least one video channel.
5. An interactive network according to claim 3 in which the at least one on-demand wideband service includes at least one wideband data transmission channel.
6. An interactive network according to claim 3, in which the at least one on-demand wideband service includes at least one videotext channel.
7. An interactive network according to claim 6, in which each wideband switch comprises a text generator.
8. An interactive network according to claim 1, in which the central service position is connected to a public switched telephone network.
9. An interactive network according to claim 8, in which each said additional optical fibre is connected in the central service position to means to provide a video tele-phone service.
10. An interactive network according to claim 1, in which the central service position is connected to a packet-switching service network.
11. An interactive network according to claim 10, in which each additional optical fibre is connected in the central service position to a packet-switching service switch.
12. An interactive network according to claim 1, in which each said individual wideband connection can carry and each said wideband service receiving unit can receive a signal having a bandwidth which encompasses simultaneously at least two television channels and frequency-modulated radio services.
13. An interactive network according to claim 12, which said signal further encompasses at least one video signal.
14. An interactive network according to claim 1 ox claim 2, in which each said wideband receiving unit includes means to provide a data signal for transmission through said at least one additional optical fibre to the central service position.
15. An interactive network according to claim 1 or claim 2, in which there are at least two passive optical taps in the or each at least one tapped optical fibre, each fibre being connected to at least three wideband switches.
16. An interactive network according to claim 1 or claim 2, in which there are seven passive optical taps in the or each tapped optical fibre, each fibre being connected to eight wideband switches.
17. An interactive network according to claim 1, in which there are at least five tapped optical fibres con-nected between the central service position and each of the wideband switches, and each wideband switch is additionally connected to the central service position by at least five optical fibres associated only with that switch.
18. An interactive network according to claim 17, in which of the said at least five optical fibres associated only with one wideband switch, two fibres are arranged to transfer wideband signals from the wideband switch to the central service position and three fibres are arranged to transfer wideband signals from the central service position to that wideband switch.
19. An interactive network according to claim 1, in which the or each at least one tapped optical fibre is connected in the central service position to signal generat-ing means arranged to supply at least one television channel.
20. An interactive network according to claim 19, in which the signal generating means supplies to the tapped optical fibre an optical signal which is modulated by multi-plexed frequency modulated signals.
21. An interactive network according to claim 17, in which each tapped optical fibre is connected in the central service position to a respective signal generating means each arranged to supply at least one television channel.
22. An interactive network according to claim 21, in which each signal generating means supplies to its respec-tive tapped optical fibre an optical signal which is modu-lated by multiplexed frequency modulated signals.
23. An interactive network according to claim 1 or claim 2, in which there is further provided at least one optical fibre connection between the central service position and a further wideband service receiving unit.
24. An interactive network according to claim 1, in which there are at least two additional optical fibres associated with each wideband switch arranged so that one fibre carries wideband signals from the switch to the central service position and the other fibre carries wideband signals from the central service position. to the wideband switch.
25. An interactive network according to claim 24, in which one fibre carries signals originating from a plural-ity of wideband service receiving units connected to said wideband switch.
26. An interactive network according to claim 1 or claim 2, in which each wideband switch operates at baseband frequencies.
27. An interactive network according to claim 1 or claim 2, in which there is between the central service position and the wideband switches an additional node through which the tapped and the switch-associated optical fibres pass.
28. An interactive network according to claim 1, in which each wideband switch is located in an on-street cabinet.
29. A method of providing interactive wideband services comprises transmitting a plurality of simultaneous fixed-time wideband services from a central service position to a plurality of wideband switches through at least one passively tapped optical fibre;
receiving a request signal from any wideband switch through at least one additional optical fibre assoc-iated only with one wideband switch;
and in response to said request signal providing at least one on-demand wideband signal through an optical fibre associated with the wideband switch which originated the request.
receiving a request signal from any wideband switch through at least one additional optical fibre assoc-iated only with one wideband switch;
and in response to said request signal providing at least one on-demand wideband signal through an optical fibre associated with the wideband switch which originated the request.
30. A method according to claim 29, in which the request signal is transmitted from one of a plurality of customer terminating units to an associated wideband switch, and said further wideband signal is supplied to the request-ing customer terminating unit.
31. A method according to claim 30, in which a further request signal is transmitted from said one customer terminating unit, and in response at least one of said plurality of wideband services is supplied to the requesting customer terminating unit.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/532,100 US4709418A (en) | 1983-09-14 | 1983-09-14 | Wideband cable network |
| US532,100 | 1983-09-14 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1220848A true CA1220848A (en) | 1987-04-21 |
Family
ID=24120381
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000446739A Expired CA1220848A (en) | 1983-09-14 | 1984-02-03 | Wideband cable network |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | US4709418A (en) |
| CA (1) | CA1220848A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5033112A (en) * | 1987-07-13 | 1991-07-16 | Northern Telecom Limited | Closed loop, programmable power and communication system |
Families Citing this family (105)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4965825A (en) | 1981-11-03 | 1990-10-23 | The Personalized Mass Media Corporation | Signal processing apparatus and methods |
| USRE47642E1 (en) | 1981-11-03 | 2019-10-08 | Personalized Media Communications LLC | Signal processing apparatus and methods |
| US7831204B1 (en) | 1981-11-03 | 2010-11-09 | Personalized Media Communications, Llc | Signal processing apparatus and methods |
| US4807961A (en) * | 1987-04-08 | 1989-02-28 | American Telephone And Telegraph Company | Local area network system |
| EP0413752A4 (en) * | 1988-04-29 | 1992-04-22 | Scientific Atlanta, Inc. | In-band controller |
| US5057932A (en) * | 1988-12-27 | 1991-10-15 | Explore Technology, Inc. | Audio/video transceiver apparatus including compression means, random access storage means, and microwave transceiver means |
| US5164839A (en) * | 1988-12-27 | 1992-11-17 | Explore Technology, Inc. | Method for handling audio/video source information |
| US5073930A (en) * | 1989-10-19 | 1991-12-17 | Green James A | Method and system for receiving and distributing satellite transmitted television signals |
| US5153763A (en) * | 1989-12-01 | 1992-10-06 | Scientific-Atlanta, Inc. | CATV distribution networks using light wave transmission lines |
| US5191459A (en) * | 1989-12-04 | 1993-03-02 | Scientific-Atlanta, Inc. | Method and apparatus for transmitting broadband amplitude modulated radio frequency signals over optical links |
| DE4024739A1 (en) * | 1990-08-03 | 1992-02-06 | Siemens Ag | TRANSMISSION DEVICE FOR TRANSMITTING NEWS AND ADDITIONAL SIGNALS |
| US5093718A (en) * | 1990-09-28 | 1992-03-03 | Inteletext Systems, Inc. | Interactive home information system |
| US5883661A (en) * | 1990-09-28 | 1999-03-16 | Ictv, Inc. | Output switching for load levelling across multiple service areas |
| US5557316A (en) * | 1990-09-28 | 1996-09-17 | Ictv, Inc. | System for distributing broadcast television services identically on a first bandwidth portion of a plurality of express trunks and interactive services over a second bandwidth portion of each express trunk on a subscriber demand basis |
| US5526034A (en) * | 1990-09-28 | 1996-06-11 | Ictv, Inc. | Interactive home information system with signal assignment |
| US5220420A (en) * | 1990-09-28 | 1993-06-15 | Inteletext Systems, Inc. | Interactive home information system for distributing compressed television programming |
| US5594507A (en) * | 1990-09-28 | 1997-01-14 | Ictv, Inc. | Compressed digital overlay controller and method for MPEG type video signal |
| US5587734A (en) * | 1990-09-28 | 1996-12-24 | Ictv, Inc. | User interface for selecting television information services through pseudo-channel access |
| US5412720A (en) * | 1990-09-28 | 1995-05-02 | Ictv, Inc. | Interactive home information system |
| FR2667750A1 (en) * | 1990-10-05 | 1992-04-10 | Philips Electro Grand Public | CABLE NETWORK AND MODULATOR-DEMODULATOR DEVICE FOR SUCH A NETWORK. |
| US5253275A (en) | 1991-01-07 | 1993-10-12 | H. Lee Browne | Audio and video transmission and receiving system |
| US5572347A (en) * | 1991-07-30 | 1996-11-05 | Alcatel Network Systems, Inc. | Switched video architecture for an optical fiber-to-the-curb telecommunications system |
| US5576874A (en) * | 1991-07-31 | 1996-11-19 | Alcatel Network Systems, Inc. | Optical distribution shelf for a remote terminal of an optical fiber telecommunications network |
| US5285305A (en) * | 1991-12-12 | 1994-02-08 | At & T Bell Laboratories | Optical communication network with passive monitoring |
| US5321541A (en) * | 1991-12-12 | 1994-06-14 | At&T Bell Laboratories | Passive optical communication network with broadband upgrade |
| US5325223A (en) * | 1991-12-19 | 1994-06-28 | Northern Telecom Limited | Fiber optic telephone loop network |
| EP0617876B1 (en) * | 1991-12-19 | 1997-02-12 | Nortel Networks Corporation | Fibre optic telephone loop network |
| FR2690799B1 (en) * | 1992-04-30 | 1994-06-10 | Cit Alcatel | OPTICAL SYSTEM FOR CONNECTING SUBSCRIBER FACILITIES TO A SWITCHING CENTER OF A TELECOMMUNICATION NETWORK PROVIDING INTERACTIVE AND NON-INTERACTIVE SERVICES. |
| US5528283A (en) * | 1992-06-22 | 1996-06-18 | Alcatel Network Systems, Inc. | Switched video distribution apparatus |
| US5995708A (en) * | 1993-03-31 | 1999-11-30 | Mediaone Group, Inc. | Method and system for delivering audio and video information |
| US5539449A (en) * | 1993-05-03 | 1996-07-23 | At&T Corp. | Integrated television services system |
| US5519830A (en) * | 1993-06-10 | 1996-05-21 | Adc Telecommunications, Inc. | Point-to-multipoint performance monitoring and failure isolation system |
| US5499241A (en) * | 1993-09-17 | 1996-03-12 | Scientific-Atlanta, Inc. | Broadband communications system |
| US5594726A (en) * | 1993-09-17 | 1997-01-14 | Scientific-Atlanta, Inc. | Frequency agile broadband communications system |
| US5581555A (en) * | 1993-09-17 | 1996-12-03 | Scientific-Atlanta, Inc. | Reverse path allocation and contention resolution scheme for a broadband communications system |
| US5581479A (en) * | 1993-10-15 | 1996-12-03 | Image Telecommunications Corp. | Information service control point, which uses different types of storage devices, which retrieves information as blocks of data, and which uses a trunk processor for transmitting information |
| US5479202A (en) * | 1993-11-01 | 1995-12-26 | Gte Laboratories Incorporated | Television receiver for accessing switched broadband networks |
| AU1333895A (en) * | 1993-11-30 | 1995-06-19 | Raymond R. Burke | Computer system for allowing a consumer to purchase packaged goods at home |
| GB9400101D0 (en) * | 1994-01-05 | 1994-03-02 | Thomson Consumer Electronics | Consumer interface for a satellite television system |
| US5534912A (en) * | 1994-04-26 | 1996-07-09 | Bell Atlantic Network Services, Inc. | Extended range video on demand distribution system |
| US5477263A (en) * | 1994-05-26 | 1995-12-19 | Bell Atlantic Network Services, Inc. | Method and apparatus for video on demand with fast forward, reverse and channel pause |
| US5768539A (en) * | 1994-05-27 | 1998-06-16 | Bell Atlantic Network Services, Inc. | Downloading applications software through a broadcast channel |
| US5734589A (en) * | 1995-01-31 | 1998-03-31 | Bell Atlantic Network Services, Inc. | Digital entertainment terminal with channel mapping |
| US5818511A (en) * | 1994-05-27 | 1998-10-06 | Bell Atlantic | Full service network |
| US5635979A (en) * | 1994-05-27 | 1997-06-03 | Bell Atlantic | Dynamically programmable digital entertainment terminal using downloaded software to control broadband data operations |
| US5666293A (en) * | 1994-05-27 | 1997-09-09 | Bell Atlantic Network Services, Inc. | Downloading operating system software through a broadcast channel |
| US5608447A (en) * | 1994-05-27 | 1997-03-04 | Bell Atlantic | Full service network |
| US5953046A (en) * | 1994-05-31 | 1999-09-14 | Pocock; Michael H. | Television system with multiple video presentations on a single channel |
| US5641319A (en) * | 1994-08-10 | 1997-06-24 | Lodgenet Entertainment Corporation | Entertainment system for providing interactive video game responses to the game interrogations to the video game engines without being processed by the host computer |
| US6334219B1 (en) | 1994-09-26 | 2001-12-25 | Adc Telecommunications Inc. | Channel selection for a hybrid fiber coax network |
| US5659793A (en) * | 1994-12-22 | 1997-08-19 | Bell Atlantic Video Services, Inc. | Authoring tools for multimedia application development and network delivery |
| US5826102A (en) * | 1994-12-22 | 1998-10-20 | Bell Atlantic Network Services, Inc. | Network arrangement for development delivery and presentation of multimedia applications using timelines to integrate multimedia objects and program objects |
| US5557320A (en) * | 1995-01-31 | 1996-09-17 | Krebs; Mark | Video mail delivery system |
| US5583863A (en) * | 1995-01-31 | 1996-12-10 | Bell Atlantic Network Services, Inc. | Full service network using asynchronous transfer mode multiplexing |
| USRE42236E1 (en) | 1995-02-06 | 2011-03-22 | Adc Telecommunications, Inc. | Multiuse subcarriers in multipoint-to-point communication using orthogonal frequency division multiplexing |
| US7280564B1 (en) | 1995-02-06 | 2007-10-09 | Adc Telecommunications, Inc. | Synchronization techniques in multipoint-to-point communication using orthgonal frequency division multiplexing |
| KR19980702155A (en) | 1995-02-09 | 1998-07-15 | 그레이스 스티븐 에스. | Epoxy Resin Compositions Curable at Low Temperatures |
| US6122482A (en) | 1995-02-22 | 2000-09-19 | Global Communications, Inc. | Satellite broadcast receiving and distribution system |
| US5736977A (en) * | 1995-04-26 | 1998-04-07 | E-Systems, Inc. | Video real estate information service |
| US5812665A (en) * | 1995-06-08 | 1998-09-22 | Ictv, Inc. | Switched channel system |
| US5719867A (en) * | 1995-06-30 | 1998-02-17 | Scientific-Atlanta, Inc. | Plural telephony channel baseband signal demodulator for a broadband communications system |
| US5930231A (en) * | 1995-06-30 | 1999-07-27 | Scientific-Atlanta, Inc. | Block spectrum receiver for a broadband communications system |
| US5794221A (en) | 1995-07-07 | 1998-08-11 | Egendorf; Andrew | Internet billing method |
| US6002502A (en) * | 1995-12-07 | 1999-12-14 | Bell Atlantic Network Services, Inc. | Switchable optical network unit |
| US5859895A (en) * | 1995-12-07 | 1999-01-12 | Bell Atlantic Network Services, Inc. | Auxiliary circuit switching for provisioning and/or repair in a fiber-to-the-curb system |
| US5809471A (en) * | 1996-03-07 | 1998-09-15 | Ibm Corporation | Retrieval of additional information not found in interactive TV or telephony signal by application using dynamically extracted vocabulary |
| US5808767A (en) * | 1996-05-30 | 1998-09-15 | Bell Atlantic Network Services, Inc | Fiber optic network with wavelength-division-multiplexed transmission to customer premises |
| US5880864A (en) * | 1996-05-30 | 1999-03-09 | Bell Atlantic Network Services, Inc. | Advanced optical fiber communications network |
| US6198720B1 (en) | 1996-12-26 | 2001-03-06 | Alcatel Usa Sourcing, L.P. | Distributed digital cross-connect system and method |
| US5970386A (en) | 1997-01-27 | 1999-10-19 | Hughes Electronics Corporation | Transmodulated broadcast delivery system for use in multiple dwelling units |
| IL122978A0 (en) * | 1997-02-20 | 1998-08-16 | Motorola Inc | Broadband interactive media |
| US6104908A (en) * | 1997-02-28 | 2000-08-15 | Hughes Electronics Corporation | System for and method of combining signals of combining signals of diverse modulation formats for distribution in multiple dwelling units |
| US6373611B1 (en) * | 1998-06-22 | 2002-04-16 | Scientific-Atlanta, Inc. | Digital optical transmitter |
| US6681231B1 (en) | 1999-07-26 | 2004-01-20 | The Real Estate Cable Network, Inc. | Integrated information processing system for geospatial media |
| US6519773B1 (en) | 2000-02-08 | 2003-02-11 | Sherjil Ahmed | Method and apparatus for a digitized CATV network for bundled services |
| US7614074B2 (en) * | 2001-04-23 | 2009-11-03 | Scientific-Atlanta, Inc. | Burst-mode digital transmitter |
| WO2002100108A1 (en) * | 2001-06-06 | 2002-12-12 | Complete Tv, Llc | Centralized aggregation of broadcast television programming and multi-market digital delivery thereof over interconnected terrestrial fiber optic networks |
| KR20030009669A (en) * | 2001-07-23 | 2003-02-05 | 삼성전자주식회사 | multi channel image encoding apparatus and encording method thereof |
| IT1403065B1 (en) | 2010-12-01 | 2013-10-04 | Andrew Wireless Systems Gmbh | DISTRIBUTED ANTENNA SYSTEM FOR MIMO SIGNALS. |
| US8396368B2 (en) * | 2009-12-09 | 2013-03-12 | Andrew Llc | Distributed antenna system for MIMO signals |
| US6879526B2 (en) * | 2002-10-31 | 2005-04-12 | Ring Technology Enterprises Llc | Methods and apparatus for improved memory access |
| US7415565B2 (en) | 2002-10-31 | 2008-08-19 | Ring Technology Enterprises, Llc | Methods and systems for a storage system with a program-controlled switch for routing data |
| US7197662B2 (en) * | 2002-10-31 | 2007-03-27 | Ring Technology Enterprises, Llc | Methods and systems for a storage system |
| US7707351B2 (en) * | 2002-10-31 | 2010-04-27 | Ring Technology Enterprises Of Texas, Llc | Methods and systems for an identifier-based memory section |
| US7672450B2 (en) * | 2004-09-09 | 2010-03-02 | Calix Networks, Inc. | Network interface device enclosure |
| GB2418088A (en) * | 2004-09-10 | 2006-03-15 | Marconi Comm Ltd | Upgrading optical telecommunications networks |
| GB2420460B (en) * | 2004-11-17 | 2009-04-08 | Marconi Comm Ltd | Monitoring of optical signals |
| WO2006071641A2 (en) * | 2004-12-28 | 2006-07-06 | Optical Solutions, Inc. | Network interface device communication via power line |
| US20070011717A1 (en) * | 2005-07-06 | 2007-01-11 | Lauder Gary M | Distribution of interactive information content within a plurality of disparate distribution networks |
| US8074248B2 (en) * | 2005-07-26 | 2011-12-06 | Activevideo Networks, Inc. | System and method for providing video content associated with a source image to a television in a communication network |
| KR100693998B1 (en) | 2006-05-12 | 2007-03-12 | 한넷텔레콤(주) | Forming method of multi channel for wire network |
| US8155202B2 (en) | 2007-01-12 | 2012-04-10 | Activevideo Networks, Inc. | System and method for encoding scrolling raster images |
| US9826197B2 (en) | 2007-01-12 | 2017-11-21 | Activevideo Networks, Inc. | Providing television broadcasts over a managed network and interactive content over an unmanaged network to a client device |
| IT1398025B1 (en) | 2010-02-12 | 2013-02-07 | Andrew Llc | DISTRIBUTED ANTENNA SYSTEM FOR MIMO COMMUNICATIONS. |
| WO2012044969A1 (en) | 2010-10-01 | 2012-04-05 | Andrew Llc | Distributed antenna system for mimo signals |
| JP5866125B2 (en) | 2010-10-14 | 2016-02-17 | アクティブビデオ ネットワークス， インコーポレイテッド | Digital video streaming between video devices using a cable TV system |
| US9204203B2 (en) | 2011-04-07 | 2015-12-01 | Activevideo Networks, Inc. | Reduction of latency in video distribution networks using adaptive bit rates |
| EP2815582B1 (en) | 2012-01-09 | 2019-09-04 | ActiveVideo Networks, Inc. | Rendering of an interactive lean-backward user interface on a television |
| US9800945B2 (en) | 2012-04-03 | 2017-10-24 | Activevideo Networks, Inc. | Class-based intelligent multiplexing over unmanaged networks |
| US9123084B2 (en) | 2012-04-12 | 2015-09-01 | Activevideo Networks, Inc. | Graphical application integration with MPEG objects |
| WO2014145921A1 (en) | 2013-03-15 | 2014-09-18 | Activevideo Networks, Inc. | A multiple-mode system and method for providing user selectable video content |
| WO2014197879A1 (en) | 2013-06-06 | 2014-12-11 | Activevideo Networks, Inc. | Overlay rendering of user interface onto source video |
| US9294785B2 (en) | 2013-06-06 | 2016-03-22 | Activevideo Networks, Inc. | System and method for exploiting scene graph information in construction of an encoded video sequence |
| US9219922B2 (en) | 2013-06-06 | 2015-12-22 | Activevideo Networks, Inc. | System and method for exploiting scene graph information in construction of an encoded video sequence |
| US9788029B2 (en) | 2014-04-25 | 2017-10-10 | Activevideo Networks, Inc. | Intelligent multiplexing using class-based, multi-dimensioned decision logic for managed networks |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4135202A (en) * | 1973-12-03 | 1979-01-16 | Communications Patents Limited | Broadcasting systems with fibre optic transmission lines |
| US4090220A (en) * | 1974-07-10 | 1978-05-16 | Communications Patents Limited | Wired broadcasting systems for processing coded data representative of subscriber station conditions |
| DE2807986A1 (en) * | 1978-02-22 | 1979-08-30 | Hertz Inst Heinrich | SYSTEM FOR INTERACTIVE CABLE TV |
| DE2828624C3 (en) * | 1978-06-29 | 1981-10-29 | Siemens AG, 1000 Berlin und 8000 München | Device for return channel transmission when transmitting programs via fiber optics |
| DE2922418C2 (en) * | 1979-06-01 | 1981-12-03 | Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt | Integrated services message transmission and switching system for sound, images and data |
| DE3104404A1 (en) * | 1981-02-07 | 1982-08-19 | Kabel- und Metallwerke Gutehoffnungshütte AG, 3000 Hannover | >>Broadband network for communications signals<< |
-
1983
- 1983-09-14 US US06/532,100 patent/US4709418A/en not_active Expired - Lifetime
-
1984
- 1984-02-03 CA CA000446739A patent/CA1220848A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5033112A (en) * | 1987-07-13 | 1991-07-16 | Northern Telecom Limited | Closed loop, programmable power and communication system |
Also Published As
| Publication number | Publication date |
|---|---|
| US4709418A (en) | 1987-11-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1220848A (en) | Wideband cable network | |
| US6538781B1 (en) | Multimedia distribution system using fiber optic lines | |
| CA2149263C (en) | Network apparatus and method for providing two-way broadband communications | |
| US6161011A (en) | Hybrid fiber coax communications systems | |
| US5343240A (en) | Bidirectional video telephony using shared channels on coaxial cable networks | |
| US5812665A (en) | Switched channel system | |
| US5008934A (en) | CATV transmission system using scrambled signals | |
| EP0712552B1 (en) | Optical fibre communications system | |
| CA2169684A1 (en) | Optical transmission system for cable television signals and video and telecommunications signals | |
| US8078056B2 (en) | Multimedia distribution system using fiber optic lines | |
| US5528283A (en) | Switched video distribution apparatus | |
| AU736033B2 (en) | An optical transmission system | |
| US6055077A (en) | Multimedia distribution system using fiber optic lines | |
| AU699920B2 (en) | Video-on-demand service using ATM cells | |
| WO1995005041A1 (en) | Optical fibre communications system | |
| Ward | Present and Probable CATV/Broadband-Communication Technology. | |
| KR0168933B1 (en) | Optic spliter of a low price video network | |
| AU665691B2 (en) | Switched video service | |
| Graves | The Heathrow broadband access system | |
| WO1997001244A1 (en) | Method and apparatus for providing access to a large number of communications channels via a relatively narrow bandwidth conduit | |
| Lee et al. | A FTTH network for integrated services of CATV, POTS and ISDN in Korea | |
| Chang et al. | Fiber-optic broad-band integrated distribution-Elie and beyond | |
| JP3070689B2 (en) | Broadcast communication system | |
| KR0168937B1 (en) | Subscriber apparatus for expanding the image service of a subscriber and structure of matching the same | |
| Robin et al. | CATV in France: Present situation and future directions |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry | ||
| MKEX | Expiry |
Effective date: 20040421 |