Satellite Phones
TfourL
It seems a very long time since the days of the 'Sputnik'! Today
satellite systems provide both voice and data communication for areas
of the world where there are no alternatives. Satelite telephones help
us to keep in touch when we fly or take a cruise. It also helps us to
keep track and stay in contact with those brave individuals who test
the boundaries of endurance and skill. We can follow their routes,
talk to them and receive photographs and video from wherever they are
and make sure someone is ready to help when things don't go according
to plan.
How do satellite telephones work? signals are sent from the satelite
phone, through an antenna to a network of satellites in orbit then
back to a ground station and a conventional phone network. Sounds good
doesn't it? Unfortunately good communication relies on an unobstructed
path from antenna to satellite. Bad weather can disrupt the signal
too. Signal link quality is generally much better outdoors but if you
are on a boat or in a plane an external antenna may be required.
At the time of writing there are five main satellite phone service
providers. Global Star and Iridium are the largest. They offer a
variety of options for both businesses and the average user. Iridium
is probably the best known for a variety of reasons. The company has
66 operational low-earth-orbit satellites with 13 spare satellites.
The satellites are in orbits about 485 miles above the Earth's
surface. The company supply to an extensive variety of markets which
include mining, construction, leisure, government and maritime. They
also provide equipment to the military and to rescue and disaster
relief organisations. Companies tend to sell their services through a
collection of service partners, value-added resellers and
manufacturers.
Satellite phones are used regularly by the military, shipping and
airlines. They also play an important part in disaster zones.
Charitable organisations use them to discover what help is needed as
soon as possible when landline phones and cell networks aren't
working. Tracking the signal can help guide helicopters into the most
affected and even isolated areas to deliver aid quickly.
Satellite phones are also being used in the fight against terrorism.
To protect the Alaskan pipeline where it is vulnerable, trucks passing
close by are fitted with satellite phones. If the truck is hijacked a
signal is sent via the network and the vehicle can be disabled
immediately.
Satellite phones are still a very expensive option. It is more
expensive than most cell phone calls. As the technology improves and
becomes more widely used, the prices should begin to drop just like
all useful technology does eventualy. At the moment Iridium state that
the cost of a satellite phone call is comparable to the cost of an
international roaming call. To improve public perception and possibly
build the consumer market the industry is fund raising in Washington
state to provide satellite phones and airtime free of charge to US
National Guard soldiers serving in Iraq.
About the Author
Steve is a software engineer and owner of http://www.satellite-phone.thecatcollar.com
source: www.goarticles.com