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HOME REVIEWS CONTACT ABOUT January 14,
2010
Mobile Satellite Communications (VSAT)
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My wife and I took a cruise to
Similar systems are now available for land vehicles,
most often trucks and RVs. These systems
are called mobile very small aperture terminal, or VSAT. The most commonly used dishes for mobile VSAT
are 0.74 Meters (About 29 inches) in diameter.
The systems designed for land vehicles are different from the ship borne
system in that they are not designed for use while the vehicle is moving, but for
when the vehicle is parked. The ship
only had a speed of about 20 MPH. There
are currently more than 10,000 land vehicle VSAT systems in use.
The signal with a satellite dish is usually superior
to that found with a "dome" antenna.
The dome systems must be kept clean and must be wiped off after a
snowstorm or rainstorm in order to maintain
good reception. It can be a hassle to frequently climb onto
your vehicle to perform maintenance on the antenna.
HDTV and TV:
It is possible to purchase a system that is capable
of simultaneous Internet communications and Television reception (including
HDTV, MHDTV). HDTV using DirecTV, Dish
Network, Star Choice, or Bell ExpressVu is
available. However, the major networks
(NBC, FOX, ABC, CBS) can be a problem. Because of FCC rules, these signals are
broadcast with spot beams, which will prevent their reception except within a
limited area.
The satellite dish deploys on command, identifies
the current location, and precisely points the dish. It usually takes less than five minutes to
achieve a communications lock, and then the system is capable of high speed
Internet communications.
It works in most of the world, even where cable
Internet and DSL are not available.
However, if you travel in the mountains, the system will not be able to
communicate with the satellite when you are on the north face of the mountain,
or in heavy forest.
Performance:
With a typical user account, downstream speed is
typically 500-800 Kbps. Upstream speed is usually less. The sales literature
says to expect up to 128 Kbps, but 20-30 Kbps is much more typical. With more advanced hardware (F2 or XF2 and
XF3 antennas), and higher monthly cost, 500 Kbps upstream and 2 MBPS downstream
speed is available. Static IP addresses
are also available (extra charge) for virtual private network (VPN)
connections. The system includes the
capability for VoIP (voice).
A mobile satellite system cost about $5000-$5500 for
purchase including installation, and $50-$160 a month for Internet
service. The bandwidth (communication
speed) impacts the price of service.
The hardware is available from several suppliers: C-Com's iNetVu, Ground Control MSS, DTI DirecStar, and the Motosat Datastorm are the main vendors. The satellite service is available from HughesNet (formerly DirecWay) and Starband. Motosat/HughesNet have historically been the most common combination, but that is likely to change.
iNetVu (Ka Band):
C-Com's iNetVu is now
offering a new technology for mobile VSAT.
The iNetVu Ka66 has been designed to take
advantage a new satellite, Telesat
The main advantage of Ka band is that it requires a
smaller dish (26" x 30") to offer very good performance levels. Ka
Band utilizes spot beams, which are more efficient than a traditional Ku
satellite (the technology used by the other mobile VSAT systems). The result is that more users can enjoy a
high level of performance. The service should be able to deliver significant
improvements in performance.
WildBlue provides the communications
service. WildBlue
also offers fixed systems. Hardware costs
and communications service should be significantly less expensive than current
alternatives for similar performance.
Professional Installation Recommended:
The installation of a mobile satellite system requires professional installation. The system is complex, and the wiring of the communications downlink is critical. Also, it is important that the external gear be mounted so that it does not get torn from the vehicle during transport, or more likely since the gear recesses when not used, during a high wind. A wind in excess of 60 MPH can damage a dish when it is not recessed. When recessed, the system is tolerant of highway speeds of less than 100 MPH. In addition, a poorly installed system can interfere with other users, so usually HughesNet will not support a system that has not been professionally commissioned.
Summary:
If you are a telecommuter, with mobile VSAT is
possible to work from just about anywhere.
VSAT can be a powerful and inexpensive method of communicating from
remote areas not supported by cellular networks. Mobile systems can communicate
with bandwidth that cannot be provided over cellular networks.
Being able to use the Internet while remote can be
important. A few years ago, that meant using a dataport
to make a phone call to a dialup Internet Service Provider (ISP).
But now our choices are getting better. WiFi
hotspots are being added, and WiMax will be available in major cities soon.
Cellular services are adding high speed, low cost data access. Other services will undoubtedly be available
in coming years.
But, for now, satellite VSAT is the only way that
will work virtually anywhere.