Wireless Wonder Or Broadband Bust?
At first this story seemed like the typical LMDS plain jane,
Though it gets better, and provides some new info.
Here are a few pieces.
JW@KSC
Local Multipoint Distribution Service: Wireless Wonder Or Broadband Bust?
(02/11/98; 1:46 p.m. EST)
By George Leopold and Brian Santo, EE Times
(snip)
"False starts" At First
Companies that intend to compete in the market are
hesitant to promise too much too fast. The big picture
"will not be clear until 1999," said Richard Sfeir,
director of marketing for CommQuest Technologies,
in Encinitas, Calif. "Realistically, 1998 is a year of
definition and positioning, and there will be many false
starts. But next year, we will get a much better picture
of what LMDS is and what it's useful for."
Despite that prediction, CommQuest, a small
developer of satellite and cellular chip sets, is already
defining LMDS products with one partner, whose
experience in antenna arrays would be paired with
CommQuest's expertise in baseband and RF
components.
The pair is working on an LMDS system that will use
Spatial Division Multiple Access technology. The
combination of antenna arrays and SDMA will create
an LMDS system that uses the smallest possible
end-user antennas, Sfeir said.
First products based on the cooperation could
become available before the end of the year. The
company is also developing LMDS products
independent of this partnership.
(snip)
Solutions to get around "rain fade" are also in hand.
Microwaves, instead of continuing to travel when it
rains, interact with raindrops -- they actually heat the
water. This has led engineers to permanently ratchet
up the power for some transmitters to compensate.
Another design calls for antennas with sensors that
detect rain; when it does rain, power is boosted until
the downpour stops.
Subscribers of the one commercial LMDS system
operating in the United States -- CellularVision's in the
Brighton Beach neighborhood of Manhattan -- have
reported on various Usenet groups that their service
comes in well, even during adverse weather
conditions.
After the LMDS spectrum auction, CellularVision may
still be the only service provider catering to residential
customers. HP's Gray said LMDS licensees will
initially target small and medium-sized business in
areas with few propagation problems or restrictions on
antenna heights.
FULL TEXT
techweb.com |
