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COMMUNICATIONS 445

Telesat was incorporated in 1969 to establish Teleglobe Canada provides interconnection with and operate a domestic system to supplement international submarine cable and communications the terrestrial microwave systems. In 1972 Telesat satellite networks linking Canada with countries Canada launched Anik Al, the worid's first commer­ outside . These international gateways cial domestic , into geosta­ or switching centres are in Montreal, Toronto and tionary orbit around the earth. Anik A2 was launched Vancouver. In Nova Scotia, Teleglobe operates an in 1973 and Anik A3 in 1975, to ensure reliable earth station which ties Canada into the international service and to keep pace with potential additional satellite communications system. requirements. Each of these had 12 channels Roughly 44% of Teleglobe's total circuits were for in the 6/4 Gigahertz (GHz) frequency range. satellite communications in 1981, and 56% tied These satellites, locked in Canada into the international submarine cable about 35 900 km above the equator, were compara­ network. It was expected that nine international ble to enormous microwave towers. Signals sent to communications satellites would be launched them could be relayed anywhere in Canada, and between 1980 and 1984. Meanwhile, Teleglobe has especially to areas too remote for economical service been party to international planning for use of fibre by terrestrial networks. optics technology in submarine calsles, and for the Initial commercial service to Telesat customers construction of new submarine cables to cross the began in January 1973 through a network of earth Pacific and Atiantic oceans. stations — facilities for picking up satellite signals Teleglobe collaborates with and also sending signals to satellites — strategically administrations in other countries and a variety of located throughout Canada. There are now hundreds international bodies to maintain and operate this of earth stations. Under federal regulations they can sophisticated globe-girdling international network. be owned not only by Telesat Canada but also by educational-TV networks, other telecommunications carriers and cable systems. 14.3 Telecommunications services Telesat Canada launched Anik B, the worid's first Telegraph services have given way to newer record commercial dual-band satellite in December 1978. communications services such as and a Like the Anik A satellites, Anik B has 12 channels in teletypewriter exchange service (TWX). From 1974 the 6/4 Gigahertz (GHz) band to replace some ofthe to 1979, the number of telegrams handled by CNCP Anik A capacity. The new satellite also operated six declined, although the telegraph still served people channels in the 14/12 GHz band, where a higher- who did not use telex or TWX. Many local telegraph power beam could be used because of the lack of offices were closed in favour of toll-free telephone terrestrial communications services using this service to the nearest area telegraph office. Newer frequency. DOC began using four of the higher- services included data communications, facsimile frequency channels in early 1979 to continue and various message services. Then videotex exploration and development of new satellite technology promised to add a new dimension to communications services using techniques developed communications in homes and offices. The new with its Hermes satellite. The 14/12 GHz band was information technologies have enabled Canadian used commercially for the first time in bringing carriers and federal agencies to provide an increasing French-language TV programming to several range of telecomunications services to remote communities in in September 1980. northern communities while linking domestic services with more countries around the world. When Anik Al and Anik A2 reached the end of their seven-year design life, they were still capable of 14.3.1 Voice communications — telephony limited use. But demand for 6/4 GHz satellite Meanwhile, Canadians have been using a growing channels to distribute radio and services number of telephones (Table 14.3). Despite the rose in 1981 at the same time as the number of increase from 13.2 million to 16.8 million telephones, channels decreased because these two Anik A the number of telephone companies fell from 850 in satellites had exceeded their lifespan. In response to 1975 to 120 in 1982. Each telephone company was this shortage, Telesat Canada launched Anik CI and responsible for integrating its facilities with those of Anik Dl in 1982. Three Anik C-series satellites were all the others. Collectively, the nine largest Canadian planned, each with 16 channels in the 14/12 GHz telephone companies, which controlled about 95% of band, to provide heavy route message service, possible the telephones, operated the two TCTS microwave business services and other new services, including TV networks and all had access to Telesat Canada's distribution. Two Anik D satellites, each with 24 satellite system for transmission of long-distance channels in the 6/4 GHz band, were also intended to calls. replace and supplement the Anik A capability. For a basic monthly charge, telephone users Canadian telecommunications networks inter­ can place as many calls as they wish in a defined area connect with networks to reach the rest and talk as long as they like. With the expansion of of North America. major cities and the merging of small towns into