If Canada's radio spectrum was real estate, the country's wireless
phone companies would be scouring the suburbs for a nice plot of
land from which to deliver their new services.
That's because Canada's airwaves are becoming crowded in the
low-frequency ranges, forcing companies and governments to figure
out ways of opening up the long-ignored ultra-high-frequency
bands.
''The ranges used by mobile services are getting very tight,'' says
Peter Minaki, manager of regulatory and technical support for
Toronto-based equipment maker Ericsson Communications Canada. ''As
a result, the {usable} bands have been moved higher and higher.''
Canada's communications companies currently do not face an imminent
shortage of radio spectrum. That's because carriers and equipment
producers have made an art form out of cramming more customers on
to the existing radio spectrum and figuring out how to operate at
higher frequencies.
''There are many tricks in the bag,'' says Al Javed, assistant
vice-president of advanced wireless systems technology for
Northern Telecom Ltd., a Canadian equipment maker based in
Toronto.
In a way, the communication companies are victims of their own
success.
Wireless phone usage is up.
Mobility Canada, the alliance of cellular subsidiaries of the
provincial telephone companies, had slightly more than two million
cellular subscribers by the end of 1996, up almost 33% from 1.5
million users one year earlier.
Canada's other major cellular carrier, Rogers Cantel Mobile
Communications Inc., saw its cellular subscribers jump by 30% last
year to 1.4 million users during the same period.
Canada also has two carriers, Clearnet Communications Inc. and
Microcell Telecommunications Inc., that will sell breast-pocket
personal communication service (PCS) by the end of the year.
The current penetration rate for cellular phones stands at
approximately 10%. With the advent of PCS service, analysts expect
40% of Canadians to be using some type of portable communications
device by 2005. The downside of such strong growth is that
companies are now faced with fast-filling airwaves.
Two decades ago, the main groups using Canada's airwaves were the
military and police forces, along with such commercial operators
as television and AM/FM radio services. By and large, however,
Canada's radio spectrum was as crowded as a nudist beach in
winter.
All that changed in the 1980s.
In that decade, technical improvements allowed users to choose from
a growing number of devices with which to communicate with other
people.
As the number of subscribers for these services increased, however,
companies scrambled to grab slivers of the radio spectrum for
their own use.
''It was akin to the Dutch Tulip frenzy {of the 1630s},'' says
Leslie Taylor, president of PageMart Canada Ltd., the Canadian
subsidiary of PageMart Inc., the sixth-largest paging company in
the U.S.
By the early 1990s, cellular carriers faced imminent overcrowding
on the airwaves in the key Toronto, Montreal and Vancouver
markets.
Luckily, help was on the horizon.
Engineers found a way to digitize communication signals, whether
video, voice or data. Now, these signals could be chopped up and
sent down wires or through the airwaves more efficiently.
As a result, new digital technical standards, such as code division
multiple access (CDMA), now provide increases of between three and
20 times existing cellular capacity.
Besides improving the network's capacity, digitization also changed
the economics of wireless systems.
The larger capacity of these networks allows more users on the
airwaves and cuts the cost of the service.
Also, in the higher frequency bands, a company can sell more
services than in lower ranges. But, in these upper bands,
companies must install more cell sites to cover the same
geographical area, because, at high frequencies, radio waves
travel shorter distances before they degrade.
For example, BCE Mobile Communications Inc. will use approximately
150 cell sites to cover Toronto with its digital PCS network. In
its existing cellular system, the carrier needs only 15 sites.
But, Randall Reynolds, BCE Mobile's senior vice-president of market
and network development, figures running his company's PCS service
is only half as expensive as operating a similar cellular service.
Besides new technology, Ottawa also opened up higher frequency
bandwidth for PCS service. In addition, companies now have an
assortment of new devices to let them place more people on their
networks without seeing signal quality drop.
Redesigning the antennas in the base stations of the cellular and
PCS networks helps. As well, companies now can reduce the radius
of the area these base stations cover.
Both techniques allow wireless carriers to reuse existing radio
channels more often.
*** Infomart-Online *** |
