KATE ANDREWS is tutor to two children on a remote sheep station at
Gunnawarra in Queensland. The property covers more than 120 square kilometres
but supports only 3000 sheep and 250 cattle. It鈥檚 a wilderness of mulga shrub,
parched by drought. Thousands of animals have died in the region over the past
18 months, and Kate鈥檚 employers, Jim and Shirley Sullivan, have had to work
hard to keep their losses to a few hundred. To see them through the most
difficult patch last year, Jim shot kangaroos for skins and wild goats for
meat.
The Sullivans鈥� nearest neighbour, another grazier or 鈥渃ockie鈥�, is 10
kilometres away; their local shop and pub, a further 90 kilometres. But the
Sullivans don鈥檛 drink, and Shirley says they rarely use the local shop these
days because 鈥渢he prices are too high鈥�. Instead, they go into town, and that鈥檚
a good two hours鈥� ride northwards in their rugged four-wheel drive. The town
is Charleville, 800 kilometres west of Brisbane, and it is home to just 3500
people. This is outback Australia.
But neither the isolation nor the straitened times prevents the young tutor
from calling her parents at home in Brisbane whenever she wants 鈥� and it鈥檚 got
little to do with her dad being regional general manager for Telstra, the
state-owned telecommunications corporation known nationally as Telecom
Australia. The sheep station, like many other small businesses and homes
across the continent, is linked to the outside world by a suite of
technologies designed to bring telecommunications to the remotest areas of
Australia.
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Connecting Australia鈥檚 remote communities to the automatic
telecommunications network in a way that was both technically feasible and
economically viable has been no mean feat. With 85 per cent of the country鈥檚
18 million people living in urban areas, and two-thirds of them concentrated
in just five cities (Sydney, Melbourne, Brisbane, Perth and Adelaide), fewer
than three million people have well over seven million square kilometres of
inhospitable terrain to themselves. Even these statistics hardly do justice to
the isolation of vast areas of Australia where sometimes population density
doesn鈥檛 even reach one person per 100 square kilometres.
So connecting the outback was a priority. 鈥淲hen you consider this nation鈥檚
vastness and widely dispersed population,鈥� says Doug Campbell, managing
director of Telstra鈥檚 Network and Technology Group, 鈥渆stablishing an effective
communications network to overcome the `tyranny of distance鈥� was far more
important for Australia than putting a man on the Moon was for the US.鈥�
Kate鈥檚 link home begins with a conventional telephone on the sheep station
at Gunnawarra, and a digital radio system outside the back door that transmits
what she says to an automatic exchange at Morven, about 70 kilometres north.
From Morven, microwave radio carries the signal, in digital form, first to
Charleville, about 100 kilometres west, and then back eastwards on one of the
country鈥檚 main microwave links to Roma, about 500 kilometres away. Repeater
stations driven by solar power, boost and retransmit the radioed call every 40
or 50 kilometres along the way. At Roma, the signal joins Australia鈥檚 optical
fibre network, one of the world鈥檚 longest, for its 300-kilometre leg to
Brisbane. Telstra laid this stretch of optical fibre only a few months ago as
part of its programme to replace the country鈥檚 microwave links, both analogue
and digital, which are being swamped by increased traffic. Finally, from a
local suburban exchange, a pair of twisted copper wires completes the
connection to her parents鈥� living room.
What makes Kate鈥檚 1000-kilometre link special is the digital radio
transmission across the remotest stretch of the connection, between Gunnawarra
and Morven. Optical fibre, microwave radio, twisted copper wires and even
coaxial cable in some places are, along with satellites, standard features of
telecommunications networks. But the Digital Radio Concentrator System, or
DRCS, is home-grown, dreamt up in Telstra鈥檚 research laboratories on the
outskirts of Melbourne. Although the system was subsequently developed and
designed jointly with NEC of Japan, it has appeared in other remote regions of
the world only after proving itself in the outback.
Iron wire
Less than ten years ago, telecommunications in the outback consisted of
short-wave radio or lines of galvanised iron wire stripped from the nearest
fence. 鈥淭he better-off might have used copper wire,鈥� recalls David Piltz, one
of Telstra鈥檚 chief engineers. 鈥淚t鈥檚 a better conductor.鈥� But neither system
was private nor reliable. Short-wave radio can be picked up by anyone with a
receiver and, because the signals bounce off the ionosphere, the success of a
call depended on atmospheric conditions. A line of cannibalised fencing, on
the other hand, was often a party line connecting several homesteads, and
conversations conducted along it tended to be faint and crackly. Furthermore,
there was always the risk that aggrieved neighbours would want their fence
wire back. As for upmarket alternatives, it was probably cheaper to launch a
satellite than lay cable, but only subscribers such as mining companies could
afford that. 鈥淣ow there鈥檚 an expectation,鈥� says Piltz. 鈥淔irst they want a
phone. Then a phone that works. Then a phone that works all the time.鈥� He
adds: 鈥淎 telecommunications service is now the norm. But you always
underestimate the demand.鈥�
And demand soared. According to Piltz, the DRCS has shown how isolated
subscribers, typically between 80 and 100 per system over an area of more than
10 000 square kilometres, can enjoy the service they鈥檇 expect if they were
living in the middle of Melbourne. Though for the moment its lines can carry
only half as much data as those in modern urban networks 鈥� 32 not 64 kilobits
per second 鈥� this is enough to convey clear conversations, passable faxes and
computer modem messages at moderate speed, all in private.
Transmission relies on a string of radio masts, up to 100 metres high and
sited at the system鈥檚 exchange and at each of its repeater stations. Close to
the top of each mast, a lightweight radio dish made of aluminium rods and
known as a Grid Pak directs the signal to the next repeater, while an
omnidirectional antenna above radiates it to the surrounding properties. At a
subscriber鈥檚 end, Telstra usually completes the link with a Yagi antenna,
which looks like an old-fashioned TV aerial. 鈥淭he Yagi provides a good line-
of-sight connection,鈥� says Piltz. It also costs only a few hundred dollars.
Occasionally though, Telstra has to fork out A$5000 to provide a
subscriber with a Grid Pak antenna. If, like the Sullivans, you happen to live
and work at the limits of a DRCS, say between 30 and 40 kilometres from the
nearest repeater, there鈥檚 little choice. Their Grid Pak is mounted on an
aluminium mast that rises about 20 metres above the property.
Onto a winner
While it all sounds simple, the system took almost a decade of research to
realise. But Telstra knew it was onto a winner. The company planned for
expansion, and the likelihood of many systems ultimately lying close to one
other, by designing the DRCS as a vast cellular network, with overlapping
cells of different systems operating at slightly different frequencies.
The DRCS network is designed to operate in two frequency bands, one at 500
megahertz across a bandwidth of 30 megahertz, and another at 1500 megahertz,
at the lower end of the microwave range, across a broader bandwidth of 100
megahertz. Personal mobile telephones, which use the 900 megahertz frequency
band, do not seem to present a problem to the expansion of the DRCS network.
That is lucky because Australians have taken to mobile phones with great
enthusiasm 鈥� 1 in 15 of the population have one, against about 1 in 20 in
Britain and 1 in 12 the US, where the first mobile phone was sold to the
American public in 1983, three years before the Australian service began.
Despite all the planning and clever electronics, however, the demand for
telecommunications in the outback has far exceeded Telstra鈥檚 wildest dreams
and, increasingly, subscribers of the DRCS network are getting the engaged
tone. Compared to optical fibre, which at the top of the range can bring as
many as 480 subscribers their own dedicated line capable of transmitting 64
kilobits per second, subscribers to an individual DRCS must share just 15
lines, each with a capacity of 32 kilobits per second.
The congestion, argues Andrews, results from assuming that subscribers in
the outback would be mostly residential rather than business users. 鈥淭hey are
not,鈥� he says. 鈥淭hey are all businesses.鈥� Most of them work locally during the
day, and then begin to use their telephones at around the same time in the
evening, after about five or six o鈥檆lock.
Telstra鈥檚 head office in Melbourne is now trying to catch up. The most
heavily congested systems in the outback are being upgraded, and to cope with
a 鈥渉uge customer demand鈥� in northern Australia, it has just formulated a
development plan that is expected to cost A$110 million over the next
five years. The plan links 1200 new subscribers to the national network and
upgrades existing connections across a vast arc of territory bounded broadly
by lines linking Alice Springs, in the centre of the country, with Broome, on
the north coast of Western Australia, and Cape York, at the northernmost tip
of Queensland.
Telstra estimates that the average cost of providing a DRCS service is
around A$20 000 per customer, with erection of the masts for the
repeater stations the most expensive single item. That鈥檚 not cheap, but a lot
less than the estimated A$50 000 per customer that it would have been
if satellites had been used instead. Nevertheless, costs soared above the
average in the more sparsely populated areas of Western Australia and the
Northern Territory. The longest link, which uses ten repeaters across a
stretch of bush east of Alice Springs, connected just three homes when it was
installed about three years ago, recalls Andrews. 鈥淎nd that worked out at
A$50 000 per customer.鈥� Not surprisingly perhaps, the connection fee is
high, but not as high as some hardened critics of telecommunications charges
might expect; it is set at a maximum of A$1500.
The fee will remain unchanged as Telstra upgrades and expands the DRCS
network, which has grown over the past nine years to about 180 systems serving
around 10 000 customers. 鈥淲e鈥檙e trying to build on the infrastructure we鈥檝e
got,鈥� says Piltz. Alternately, in areas that it hasn鈥檛 already linked into the
telecommunications network or where it decides to 鈥渙verlay鈥� existing DRCS
systems, Telstra will install a new version of the digital concentrator
system. The latest technology is the High Capacity Radio Concentrator System
(HCRCS), which is made by Philips-TRT of France. Carrying four times as much
information as the DRCS, it provides 30 lines capable of transmitting 64
kilobits per second and yet still conforms to the original broad
specifications of a telecommunications network in the outback: 鈥渕inimum costs,
least complexity鈥�.
Even on the old DRCS, however, getting through to Kate Andrews in
Gunnawarra from London seems straightforward enough. Just 5 seconds after
dialling the last digit of her number, the telephone is ringing at the sheep
station. Kate isn鈥檛 around it turns out, and it鈥檚 Shirley Sullivan on the
line. She鈥檚 as astounded to be connected to someone in a basement flat in
north London as her caller is to be linked to the outback. 鈥淚鈥檝e never spoken
to London before.鈥�
So what鈥檚 the service like? 鈥淲e鈥檝e never had any problems,鈥� she says. 鈥淵ou
can always pick up the phone and get through. It鈥檚 the other end that鈥檚 the
problem 鈥� they鈥檒l be engaged.鈥� Is it an improvement? 鈥淥h yes. Before, it was
a party line system and you had to yell down the line. And they had to yell
back at you. And most of time you couldn鈥檛 understand what they were saying.鈥�
Shirley鈥檚 voice is crystal clear, and she doesn鈥檛 seem to be yelling.
Tales of crocodiles and lightning
鈥淎SK him about the crocidiles,鈥� they said, 鈥渁nd that telecoms guy who got
in too deep.鈥� John Andrews, Telstra鈥檚 man in Brisbane, has a reputation back
in the corporation鈥檚 head office in Melbourne for spinning a good yarn. So he
does.
鈥淐rocs are a bit of a problem,鈥� said Andrews. 鈥淭hey鈥檙e becoming extinct,
and the government has banned shooting them.鈥� But it鈥檚 not crocodile
extinction that is the problem for the gangs of workers he has out maintaining
lines and laying new ones in northern Queensland.
It all happened almost a year ago, he says, during the last wet season. The
bitumen road finishes at Cooktown, about 160 kilometres north of Cairns, and
further travel becomes impossible in the rain. 鈥淭hen the ferry broke down, and
he decided to swim,鈥� recalls Andrews. 鈥淚 don鈥檛 know if they even found bits of
him 鈥� you do need to be careful.鈥�
The victim had been a contract worker, engaged to clear undergrowth from
around the bases of the repeater stations, which boost and retransmit radioed
signals. 鈥淪ince he got eaten, we haven鈥檛 been able to find anyone else to do
the job.鈥�
Andrews has been with Telstra, and its predecessors, the Postmaster
General鈥檚 Department and Telecom Australia, all his working life. The
corporation even sponsored him through his electrical engineering course at
the University of Queensland in the late 1950s. 鈥淭hey were offering the most,
six pounds a week, against three pounds 10 shillings.鈥�
Over nearly four decades, he鈥檚 witnessed an extraordinary expansion in the
national network, and its development from one dominated by manual exchanges
and crackly transmissions to a reliable, automated service that boasts of
providing more optical fibre per head of population than any other in the
world. More recently, he鈥檚 watched the avuncular state-owned corporation he鈥檚
grown up with make swingeing cuts in its workforce in an effort to confront
deregulation of the service and the challenge of competition.
But some things never change, among them the problems that the network
faces from Australia鈥檚 natural environment. Nylon sheath now protects cables
against the termites, says Andrews, but 鈥渞ats have got bigger teeth 鈥� and
there are millions of them in Queensland and New South Wales鈥�. So new cables
are laid deeper in the ground, down to 1.2 metres, but that doesn鈥檛 always
work. During a drought two years ago, he recalls, wide cracks opened up in the
鈥渂lack soil country鈥� and went down nearly 10 metres. 鈥淭he rats made their
homes in the cracks, and were chewing up cable every day.鈥� Telstra is now
experimenting with tougher sheaths.
And lightning remains a problem. There are 15 million lightning strikes a
year in Australia, each discharging between 50 million and 500 million volts,
and dissipating enough energy on average to keep a 40-watt bulb burning for a
year. When copper cables are hit, they are destroyed. But there are fewer
metal conductors on the network these days, as optical fibre takes over. The
trouble now is that when you bury the fibre in a trench, the corporation鈥檚
metal detectors can鈥檛 find it again to repair. So Telstra has tried to
compensate by laying metal marker tape along the surface. Lightning strikes
are indiscriminate and unsparing, however, Telstra tried 鈥渕arker posts鈥�, which
are supposed to indicate the route of a subterranean fibre every 200 metres or
so. 鈥淏ut the posts don鈥檛 go in the right place, or people pinch them for
building a barbecue, or for boiling the billy on,鈥� says Andrews.
Concrete posts would be heavy enough to dissuade thieves, but they鈥檙e too
much trouble for Telstra too. And as for plastic, 鈥淐attle like scratching
their backsides on it,鈥� observes Andrews enigmatically. 鈥淭here鈥檚 no answer to
it yet.鈥�