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Dashboarding
with Globalstar
by
Mark Sedenquist
The
other day I received e-mail from an English tourist who berated
me for failing to deliver the simple answer he was sure existed.
How was he was going to connect to the Internet using a laptop
computer while he was parked in a campground in Yellowstone
National Park? He was quite incensed that nobody, including
the Road Wirer would give him a guaranteed way to check his
investment portfolio as he traveled around the country. Well,
after nearly seven years of daily attempts to connect to the
Internet in wireless dashboarding mode, I can say only this
with confidence-- we are getting closer.
In
recent Road Wirer columns I have mentioned some of the pending
systems that will be using existing Geostationary Earth Orbit
(GEO) satellite constellations. GEO satellites present two
primary problems for use by dashboarders. First, the distance
of approximately 22,000 miles from earth requires a fairly
powerful phone, and the distance that the RF signal must travel
causes a noticeable delay for voice communication. Second,
there are problems aligning the mobile receiver with sufficient
accuracy to enable the system to work properly. Medium Earth
Orbit (MEO) systems are much closer at around 6,200 miles,
but it is the Low Earth Orbit (LEO) constellations that are
likely to offer the best solution to dashboarders. Globalstar
is a 48 LEO satellite constellation that operates about 913
miles above the earth. Globalstar is not the final solution
that dashboarders have been waiting for, but within two months
it should be ready to give you sufficient service to download
your e-mail and perform limited web surfing from just about
anyplace in North America.
Last
May, Laura Malter from Qualcomm provided us with the use of
a GSP-1600
Portable Tri-Mode Satellite phone for five weeks of field
tests. Our testing regimen was designed to demonstrate how
the Globalstar system can be used by dashboarders working
on the road. The first test evoked near euphoria. I reached
the RoadTrip America website in a canyon near Julian, California,
a remote spot not far from an abandoned gold mine.
The
GSP-1600 is designed to look for the availability of CDMA digital
signals (IS-95) first, move to analog AMPS (IS-41) and then to Globalstar
(G*) to secure the required connection. For the most part I used
the GSP-1600 in satellite mode only during the test trials, since
I was primarily interested in the system's capability to send two-way
data. At the time of the trials, I did not use the bandwidth
meter that I now employ when I review hardware. The indicator
I used was the time required to send files representative of the
type and size that many dashboarders hope to send on a daily basis
from the road. These files included a 273K JPG file and a 13K text
file. I also used AOL and the AOL FTP program and sent both sets
of files via analog (AT&T) and Globalstar. Due to a hardware
problem, we used the Pentium 75 laptop instead of using the faster
processing speed of the 466MHz IBM laptop. The antenna connection
was the standard G* external mount and a high-gain cellular for
the analog tests.
Generally,
the log-on sequence (15 to 45 seconds) and the transmission
of the smaller text file (13 to 28 seconds) was nearly three
times faster when we used the G* network. But a near-magical
difference was observed while sending the larger JPG file.
Analog transmission averaged about 25 minutes and the G* was
about 6 minutes. As many of you know, managing to remain connected
for a full 25 minutes of analog time is a darned hard thing
to accomplish in most areas of the country. Plus the added
benefit of being able to use the packet transfer protocol
allowed the system to pick-up the data stream in the appropriate
segments when the connection was momentarily lost.
GlobalStar
is quoting real-time thru-put of 7.7K to 9.6K, which seems
pretty consistent with our own findings. These transmission
rates, although faster than analog, are considerably slower
than the 64K speed currently available from Immarsat, and
much slower than the 400 K up-leg and 1.5M down-stream rates
that are being quoted by other satellite contenders. I wish
I could write, "It works today," but… it isn't quite
ready for prime time use. The best estimate is that packet
data service should be ready for rollout by November. Costs
of the airtime use and the equipment are another issue that
has yet to be fully resolved. It is probable that the car
kit version of the Tri-Mode GSP-1600 should be available for
approximately $1700. This figure includes a $500 rebate on
the transceiver and the commitment of a 24-month service plan.
Pricing
air-time use is very problematic now, since each of the service
providers linked by the G* network will set their own rates.
It is likely that a minute of packet data usage will be similar
to minutes currently charged for voice service. For the Road
Wirer, a typical month of 1000 minutes should cost around
$1 per minute. Since we have paid as much as $3.50 a minute
in analog roaming situations, G* is definitely going to be
a vital and appreciated part of the connection solution that
we have been seeking. I will provide an update on the pricing
information when the G* packet data service is launched in
a few weeks.
The
Globalstar system that I tested did not work 100% of the time,
but it did allow me to update pages on the RoadTrip America
website in very scenic off-road locations with a minimum of
tinkering. When it worked, it worked flawlessly, which means
we are all several important steps closer to our dashboarding
grail. Those in the know can appreciate the progress being
made by companies like GlobalStar. In the meantime, it won't
be long before I receive another strident message from someone
who's sure such connections have been available for decades!
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