Field Trial of Optical Fibre Cable-TV System Optical Fibre System for ...

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Fig. 4 The head end at Farsta Fig. 5 The subcentre at Skarpnäck Fig. 6 The receiving antenna at the head end Farsta Program inputs Program inputs at the main centre are obtained from a receiving station at the Farsta automatic exchange. The station which is equipped with a 5-metre parabolic antenna receives broadcasts from the European Communications Satellite ECS on 12 GHz. Fig. 6 shows the receiving antennas at the main centre. The following programs are at present received from ECS and transmitted to the trial areas: - Sky Channel from UK - Music Box from the UK - TV5 from France. \«SC»*jÄiääii. There is also a smaller parabolic antenna on the roof of the automatic exchange for reception of television transmissions from the Russian TV satellite Ghorizont. The Russian program is also transmitted to the trial areas. Before the French and Russian TV programs are transmitted to the households they must first be converted from SECAM to PAL, as France and the Soviet Union use a different TV standard. This conversion is done at the head end. A local television channel is also available for clubs and other associations. This channel also provides text information about the programs to be transmitted on the various channels. The Swedish programs TV1 ochTV2,the sound radio programs P1-P5 and a community radio program are received at the subcentre at Skarpnäck and modulated into the 47-400 MHz band which is transmitted to the households on the conventional cable-TV network. Subscriber equipment In a future service-integrated fibre-optic broadband network fibre cables will also be used for subscriber terminations. The networks will have a starshaped structure and different services, such as "narrow-band ISDN", highspeed data, videotelephony, videoconference, will be transmitted over one
158 Switching equipment Fig. 7 Future service-integrated broadband network Individual optical fibres are run to each flat from centrally situated switching equipment for video, audio, data and text transmission. The subscriber can himself select via the switching unit what he wishes to see and pay for of the TV programs offered Fig. 9 The demonstration room at Skarpnäck and the same fibre in addition to television and stereo radio programs. Digital techniques will be adopted both for transmission and switching (fig. 7). To give an idea of the form that a future subscriber network may take, a demonstration plant for integrated fibre-optic subscriber termination has been built up at Skarpnäck. The subscriber termination comprises a video conference room and a demonstration room arranged on the same premises at Skarpnäck. The premises are connected via optical fibres to the Skarpnäck subcentre, fig. 1. The demonstration room is designed as the living-room of the future. It contains a television set, stereo set, telephone, Datavision, video disc, compact disc player, large-screen TV, home computer equipment, etc. The room will later be furnished with equipment for still more futuristic services such as videotelephony, video library, and for shopping and banking via a home terminal. The block diagram of the demonstration plant, is shown in fig. 8. The equipment is described in greater detail in another article in this issue of Ericsson Review 2 . The demonstration room, fig. 9, is connected via optical fibres to video and audio switching equipment in the subcentre. In the demonstration room a small remote control unit (infrared transmitter) is used to select the desired TV and stereo program. A control signal is transmitted digitally over the fibre-optic subscriber line to the microprocessor in the switching equipment, which sets up the connection. Wavelength multiplexors enable a TV and a stereo program to be transmitted simultaneously over the subscriber fibre, which is also used for the transmission of control signals in the opposite direction. The video and audio signals are transmitted over the subscriber line using analog pulse frequency modulated systems. In the demonstration room there is also a telephone set connected via an optica fibre to the Farsta telephone exchange The video conference room, fig- 1 ° l! connected via two optical fibres to video switching unit at Farsta. The u r
Page 1 and 2: ERICSSON REVIEW 4 1985 Field Trial
Page 3 and 4: Trial of Optical Fibre Cable-TV Sys
Page 5: Head end (HC] 280 Mbit/s Farsta aut
Page 9 and 10: 160 Fig. 10 The teleconference room
Page 11 and 12: GERHARD GOBL Public Telecommunicati
Page 13 and 14: Fig. 5, above left Two-channel A/D
Page 15 and 16: Digital input signals Digital outpu
Page 17 and 18: Power ZAV 280/4 has individual powe
Page 19 and 20: Wavelength Division Multiplexing fo
Page 21 and 22: 172 Subscriber side BP-890 Controll
Page 23 and 24: Fig. 8 Transmission characteristics
Page 25 and 26: Most computer cabinets are 19" wide
Page 27 and 28: 178 Fig. 5 Modems in Series 7 Modem
Page 29 and 30: Computer Aided Production of Plasti
Page 31 and 32: Fig. 4 Product geometry displayed o
Page 33 and 34: Rectifier for Mobile Telephone Syst
Page 35 and 36: I OR | OFU OS I CMUP HlsHi W±±±h
Page 37 and 38: 188 Fig. 6 The rectifier with the o
Page 39 and 40: Fig. 9 Rectifier BMJ A01 001 with t
Page 41 and 42: The Renewal of the London Undergrou
Page 43 and 44: 194 Rickmansworth, and the Loughton
Page 45 and 46: 196 Fig. 5 Optical fibre cable rout
Page 47 and 48: 198 In planning the optical fibre n
Page 49 and 50: Fig. 9 The digital telephone DIAVOX
Page 51 and 52: 202 Fig. 11 Transmission equipment
Page 53 and 54: 204 Fig. 2 Automatic testing of mul
Page 55 and 56: 206 Relative occurrence for F Fig.
Page 57 and 58:
Fig. 5 Field testing of a 140 Mbit/
Page 59 and 60:
210 Fig. 7 The system down time as
Page 61 and 62:
MTBF (years) Equipment 2-5 Transmul
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