Technologies currently hold a predominant position in national and international politics. They are the object of an important investment effort and of a voluntary management. They appear today as one of the fundamental component of any strategy capable of furthering the mastery of the future of our countries. The complexity of the system which will be implemented on the basis of these technologies, particularly of the communication system , does not prevent the risk of enslavement of one country by another.Therefore, in the long run, there is a risk of a destabilisation of the world system. Only a strategy of international cooperation on new technologies and their implications can truly prevent such a risk. France has affirmed its willigness to cooperate with the countries joined at the summit of Versailles and has affirmed its desire to encourage the growth of individual cultures including those of the Southern countries.
1 - the main stakes
2 - some foreign analyses
3 - the convergence of needs and networks
4 - broadband cable networks : how they contribue to social integration
5 - where are those interactive services ?
6 - what is at stake for residential subscribers
7 - what is at stake for business and institutionnal users
8 - what is at stake for the producers of audiovisual materials
9 - what is at stake for the telecommunications companies
"Bandwidth on a metropolitan CATV cable plant is a resource that may be compared today with the crude oil beneath the Arabian desert at the turn of the century. It will provide a radically new two-way communications medium for homes and businesses, and it will change not only the way we communicate but possibly even the way we live." This prediction was made last year by William Zachman, vice president of research for International Data Corp. If Zachman is right, and our research tends to indicate he is, then fiberoptics will become the transmission medium that will facilitate two-way broadband communication. However, many of the multiple system CATV operators in the U.S. as well as many of the manufacturers of fiberoptic waveguide and cable believe that interactive video systems are not really very important. They are wrong. Broadband fiberoptic systems have just begun to impact the U.S. communications market. And within 5 years, tremendous changes will occur not only with regard to growth, but with regard to the supplier industry structure. Interactive, switched, video systems in the U.S. go back to the early 1960s, and the experiments at Bell Laboratories with what was then called Picturephone. This was com-pressed video transmission via telephone lines from one subscriber to another. Field trials were conducted in several U.S. cities for a period of years. But the commercial response to Picturephone at that time was so lacking that AT&T discontinued the trials and the work. But that is changing. Part of the reason for the change is due to the changing communication needs of the U.S. and of the world: the increase in the amount of information used by large numbers of people, the concurrent rise in the use of computers, the digitization of communications media, the rise in the level of experience with electronic communications, and perhaps most importantly the convergence of audio, data, image and video communications. There are technological reasons for the slow implementation of broadband fiberoptic systems. Installations have been hampered by multi-mode optical waveguide capable of transmitting only four or five channels using digital PCM. And the cost of fiberoptic systems which require transceivers for each fiber is still higher than coaxial systems. But this, too, is changing. True, coaxial cable will remain the dominant transmission medium for the U.S. CATV industry over the next 10 years. But fiberoptic systems will increasingly penetrate that market. The U.S. CATV cable market is growing at a rapid rate from $250 million in 1981 to nearly $700 million in the early 1990s. Plant mileage will grow from 234,000 km installed in 1982 to 360,000 km installed by the late 1980s. The market is not only growing, but it is also undergoing a segmentation that includes CATV, local area networks, and telecommunications. This segmentation insures a long period of maturity and profits for the supplier industry structure.
I come before you today in this auspicious setting as the chairman of the board of a laser manufacturing company, and therefore I will, of course, address myself to the subject of lasers, per se, in the course of this presentation. But I must also offer to you my additional qualifications, namely the fact that I serve, too, as the chairman of a company called BroadBand Communications, because it is those very words -- broadband communications -- which more adequately describe the real subject at hand.
In September 1979, the French Administration decided the launching of the city of Biarritz wiring with optical fiber cables. Following the engineering study, the project has been designed in order to be able to connect 5000 subscribers in the final step. During the initial phase, 1500 subscribers will start to be connected in autumn 1983, around one main center and two secondary centers.
Following experience gained with the Fibrevision cable TV trial at Milton Keynes the implementation of a large scale multi-star wideband local network is being investigated by British Telecom. An update on the Fibrevision trial is given followed by an outline description of a future multi-star wideband network.
In Japan, fiber-optic transmission systems were in the experimental stages in the early 1970's. By the end of the decade, the technology had entered the era of practical use in various fields. Today, there is a dramatic increase in the number of optical fiber transmission systems installed in Japan each year. From 1977 through 1982, each year has witnessed the installation of more than 50 new systems. By late 1982, more than 500 systems were in use across the country. At the present stage of development, the major users of optical fiber transmission systems are: the electric power industry with 116 systems; the steel making industry with 70 systems; railroads and highways with 56 systems; building management and office automation systems with 27 systems; the public sector including CATV with 24 systems. Following an overview of the current status of optical fiber transmission systems in Japan, future developments and possible new applications will be discussed.
After a short description of previous optical fiber tests within the city area of Berlin (West) the reasoning that led Deutsche Bundespost to the concept of the BIGFON systems test is explained. The requirements for and the basic architecture of a local broadband network are dealt with in some detail. The scope of solutions offered by the six BIGFON contractors is demonstrated by means of block diagrams of two rather different designs. Some information on the present status of the BIGFON project is given; in closing, questions of cost, introduction procedure and need for further research are discussed as well as the problem of broadband long distance connections.
An advanced Bell Laboratories and Western Electric designed electronic information retrieval system utilizing the latest Information Age technologies, and a fiber optic transmission system is featured at the Walt Disney World Resort's newest theme park - The Experimental Prototype Community of Tomorrow (EPCOT Center). The project is an interactive audio, video and text information system that is deployed at key locations within the park. The touch sensitive terminals utilizing the ARIEL (Automatic Retrieval of Information Electronically) System is interconnected by a Western Electric designed and manufactured lightwave transmission system.
The fast increasing demand for domestic or professional information and communications services, plus the availability of new technologies (fiber optics, satellites), are already enabling the creation of high performance, expandable networks.
Optical wavelength division multiplexing (WDM) systems, with signals transmitted on different wavelengths through a single fiber, can have increased information capacity and fault isolation properties over single wavelength optical systems. This paper describes a typical WDM system. Also, a state-of-the-art survey of optical multimode components which could be used to implement the system is made. The components to be surveyed are sources, multiplexers, and detectors. Emphasis is given to the demultiplexer techniques which are the major developmental components in the WDM system.
Feasibilities will be discussed which will be offered by the use of fiber optics as solid state dosimeters. By the combination of properties of solid state dosimeters and the specific advantages of the optical communication technique, these sensor systems are introduced to new areas of applications. Since there is no long-term experience these sen-sor types will be applied to those environments where conventional types fail ( high tempe-rature, high humidity extreme fluctuations of dose range, smalles available sensor volume, adverse environments ). The proposed applications, used as examples, will be discussed.
This paper discusses the particular use of phosphors and optical fibers called Fluoropticm Thermometry. The principles of operation and the particular characteristics which open new application areas to thermometry are reviewed. Several representative applications are discussed including: medical hyperthermia, high voltage electric power, industrial rf heating, nuclear magnetic resonance, and electronic fabrication such as sputtering, ion implantation and plasma etching. New extensions of the technology via improvements in fiber characteristics, and the next generation of multi-probe systems are also discussed.
Fiber optic couplers have been developed specially for nuclear chemical spectrophotometric applications. Coupling devices are described for TELEPHOT® industrial photometers and different commercial spectrophotometers, as well as the probes and measurement cells employed. The value of optical multiplexing is discussed for the time-sharing assignment of instruments to several work stations. Non-nuclear applications in medical analysis are also mentioned, together with the possibilities offered by these devices for uses other than spectrophotometry.
Fiber optic couplers have been developed specially for nuclear chemical spectrophoto-metric applications. Coupling devices are described for TELEPHOT industrial photometers and different commercial spectrophotometer, as well as the probes and measurement cells employed. The value of optical multiplexing is discussed for the time-sharing assignement of measurement instrument to several work stations. Non nuclear applications in medical analysis are also mentioned, together with the possibilities offered by these devices for uses other than spectrophotometry.
This study arose from the needs of fundamental particle physics research. Some of the detectors we use work via the production of light, usually detected by photomultipliers. These are the fastest physical detectors amongst which are those using the light emission properties of certain bodies on the passage of a charged particle.
The application of large diameter plastic-clad silica (PCS) fibers inside a seven MV electrostatic accelerator is described. Voltage gradients along the fibers exceed 1.5 MV/m in this application. The fibers are employed in serial digital data links for a control system installed in the high-volt.ge terminal of the accelerator. The use of electronics, I-R components and fibers in this extremely hostile environment will be discussed. Several other applications of these large diameter fibers are also mentioned.
Remote sensing data obtained from satellites such as LANDSAT 1 and 2 have prove° to be very useful for earth resources management. However, efficient interpretation and effective utilisation of data can ue achieved only with the support of the ancillary data obtained under 'in situ' conditions. For this, a number of spectro-rauiumeters ranging from simple band to continuous data recording systems are used. But oue to the instrumentation limitations, these can be used only in limited areas. In the present paper, a continuous spectral signature collecting system using all fibre optical system is describeo. It is seen that such an instrument can be used for recording data from objects ranging from 2 sq.mm. to 2 sq.m. and in the range from 0.4 to 1.1 microns with variable spectral resolutions. besides, the spectral signature collection, this all fibre optic radiometer finds extensive applications in other biomeuical and physical sciences.
There is considerable growth world-wide in the use of fibre optics in industry and commerce. One of the main reasons given by users so far for installing fibre optic systems is the complete freedom from electrical interference and resulting data integrity. The reliability of fibre optics has now been established by the telecommunication networks, but there is still conservatism amonast some potential industrial users. It is mainly the larger organisations in process control and users of large data processing organisations that are taking up fibre optics enthusiastically. The systems are now competitive with alternative systems and there is a large number of suppliers of components and subsystems world-wide. Integrated circuit signal processing is now being incorporated into transmitter and receiver housings and complete fibre optic local area networks are beginning to challenge brand name copper systems Lack of standards at present however, may present some difficulties for the potential user wishing to fabricate his own system. In the future, the development of integrated optic components will add another dimension to fibre optics in switching and signal processing and fibre optic sensors will challenge traditional transducers- The continued growth of fibre optics in industry and commerce seems well assured.
The optical triggering of a power switch formed by a set of thyristors connected in series has been realized by the flash of a lamp. The flash is guided through optical fibers towards interface triggering cards of the thyristor gates. A systematic control of the gate pulse amplitudes is operated by a threshold device in the triggering cards. A second fiber optical link connects this card to a control logic unit having a sound alarm. This fiber optical triggering system provides a new solution to the problem of triggering a set of high power thyristors. This system was developed for the generator circuit of our pulsed magnet delivering 40 teslas.
The IEEE 488 (or IEC 625) interface standard for programmable instrumentation is used widely, all over the world, in laboratories and manufacturing pants. The main limitation of this data bus system is distance : the maximum cabling distance is 20 meters or 2 meters per instrument, whichever is less. Fiber optics can help us getting rid of this serious distance limitation problem. DATEABUS 488 is a ring shaped physical local area network, which is totally transparent to the IEEE 488 protocol. It uses optically bypassed, fail-safe, transceivers (Servotaps), for high reliability. Maximum distance between stations is one kilometer. Maximum data rate is 140 kilobyte per second. The number of stations can be higher than 100, but addresses are limited to 31 by the protocol. The noise immunity inherent to optical fiber precludes any deterioration of bit-error-rate.
A very broad spectrum of technical literature has reported the activities and achievements in the field of fibre optics over the past ten years. The output in the past two years has been immense. Most of the reporting has been related to the world-wide achievements in optical transmission of data in public telephone networks. However, the less spectacular progress in commerce/industry has received significant exposure in the same period. The classical properties of optical fibres are being married to electronic circuitry to provide precision mark sensing in high speed processing equipment.
In recent years, tremendous interest has been evoked in the development of fibre optic inertial systems. Apart from this, the optical fibre systems are proving their might in the areas of monitoring of the environmental parameters. In addition to this, optical fibre systems find extensive applications in satellite and rocket based systems. In this paper, the highlights of these new technologies have been presented with special emphasis on communication aspects between satellite check-out and data reception communication links between ground station and tracking antenna. Also, few other possible applications of fibre based instrumentation onâ€"board satellites are dealt with.
Single-mode, polarization-dispersionless optical fibre transmission is a next step to broadband coherent systems /transmission of information, optical data bus and telemetry/. Various fibres for coherent systems have been lately tried 1-3. The problem of coherent optical transmission is a subject of extensive research.
We show that several independant multiplexers can be grouped together in the same optical component. The multiplexing function is completed by a simple common optical element. These components called shared optical function components allow the reducing of the wavelength multiplexing cost.
Since the introduction of optical wave guide as a transmission medium, coupling of the optical fibres has become an important part of it for every connection to be made, losses will occur and influence the quality of the system. Even permanent splices require a low loss coupling.
The low attenuation and wide pass band of optical fibers was put to good use in the manufacture of a cablelinking a color camera to its control box, located in a studio or broadcasting van, several miles distant.