Benefits Of Comsat System For Australia And New Zealand

Press, Volume CVI, Issue 31318, 14 March 1967, Page 7

Benefits Of Comsat System For Australia And New Zealand

Nov is the time for Australia and New Zealand to begin consideration of the advantages to be gained from a satellite communications system serving the whole Australian and New Zealand area. Already both countries belong to the American-in-spired Comsat Corporation which aims to exploit satel-

lites for international communications. But a regional system, not subject to external control, will be essential to serve our future internal needs. This realisation has already dawned in Canada where moves are afoot to **■ tablish a 75-million dollar domestic communications satellite system (CANSAT) to

handle all of Canada’s message and data traffic as well as coast-to-coast colour TV on several channels. The need for such a system in this part of the world is only slightly less than in Canada. The Canadians fear United States domination of their domestic television service and the problems of communications throughout Canada’s vast territory give satellites a competitive edge that would not apply in small populous countries such as Great Britain or Japan, but certainly applies here. Costs Compared The steadily rising cost of extending telephone, telex, facsimile and data links, to say nothing of television, is in contrast with the falling cost per unit bandwidth of satellite relays. For tenninai-to-terminal distances greater than a few hundred miles the

v* usvvunw W4UO WVUUIU* ieally, subject to two important provisos. One: the high cost per satellite requires it to be shared by many links simultaneously This will not be a problem with the new multiple-access satellite designs now on the drawing board. Two: dose integration with existing terrestrial networks is vital for full benefits and economies to be gained. In other words satellite communications should aid rather than supplant existing services. There is, however, the added advantage that new services become possible; such as unbroken two-way links with commercial aircraft anywhere in the region, nationwide edu cational TV (which could bt in full colour) and perhapi a business system servinj stock exchanges, banking anti commerce. Pessimists Confounded These vistas in the field oi communications have until recently been little more thar dreams. They are now real and have been opened wide by a recent revolution in satellite technology, namely the amazing success of the synchronous orbit satellites such as Syncom and Early Bird. They have confounded the pessimists by proving to be durable and easy to maintain in position. Almost overnight they have superseded the earlier comsats of the Telstar type. According to Mr A. R. Cooper, director of America’s N.B.C. radio and television network, the advantages of synchronous satellite systems have “all at once made obsolete and anachronistic” the use of terrestrial

■ methods for long-distance i communications. i It is not too early for ! studies to commence on a I regional comsat system for Australia and New Zealand. The heart of the system would be two stationary satellites 22,300 miles above the equator at longitude 145 degrees east, which is almost ' over New Guinea. I Three Beams One satellite would be a spare, operating on standby. To make the best use of available power the satellite antenna system should produce three beams, two covering opposite sides of the Australian continent and the third covering both islands of New Zealand. Within the beam area, receiving antennae of 10 to 10 feet diameter would pick up a strong signal from the satellite. Outside the beams larger antennae would be needed. The ground transmitting stations would require antennae 30 feet in diameter. The stationary position of the :

! satellite would not require any of the antennae to be 1 steerable. This fact alone . saves tens of millions of dol- ' lars and enables the cost of ; a complete ground terminal for transmission and reception to be kept under a mil- : lion dollars. A station for - reception only would cost less than 100,000 dollars. Challenge To Industry Much of the equipment, including the satellites, could be built locally and would provide a challenge to our electronics industry. At present Canada has the edge on us because the Defence Research Telecommunications Establishment in Ottawa biiilt the two outstandingly successful Alouette ionosphere satellites. Alouette I is still operating properly after four and a half years in orbit—a record for full operation. Some of the credit for this achievement belongs to a New Zealander, Dr. C. A. Franklin, who designed Aiouette’s magnificent radio transmitter and who is now in charge of the electrical

design of the forthcoming Canadian Isis series of satellites. This simply goes to show that this part of the world can produce men of the calibre needed to establish our own comsat system. Pressure Or. At a rough guess it would seem likely that our countries will begin to lose financially, particularly in the field of colour television, if we do not have our own comsat system operational before 1975. This leaves little time for planning. At present, in North America, five different proposals for domestic satellite television and communication systems have been put forward. The pressure is on and progress will be rapid. We should wait long enough to see the trend of developments then lose no time in setting up a system of our own before we are squeezed out After all, in the three and a half years since Syncom 2 was launched the United States has placed 20 stationary comsats in orbit.