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There is a great deal of information related to VSATs on this site which can
make it a little confusing. To simplify matters, this page offers a little
more detailed navigation.
The
VSAT Report is based on primary research by COMSYS involving site
visits and interviews with companies from Australia to Argentina and from
Pakistan to Peru. This makes the information which we provide second
to none. In addition, we are constantly working in the VSAT industry and
are involved in acquisition evaluation, prospect valuation, forecasts,
opportunity identification, diversification and statistical analysis. All
this helps us provide unique, high quality advice and information.
First, have a look at the FAQ, just to get started.
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is extremely active in all areas of the VSAT business, not only are
we a Founder Member of the Global VSAT Forum, we were the prime initiator
of its formation. To find out more about VSATs, the industry and our role
in it, click the icon. There is information on the Global VSAT Forum as well
as downloads to articles we have written on the VSAT business for various publications
over the past few years.
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Frequently Asked Questions - What would you like to know about VSAT systems?
- What do you mean by a VSAT?
- VSAT stands for Very Small Aperture
Terminal - its a catchy acronym and as such its been adopted by all and
sundry for every type of satellite product from small components of a
system to complete systems. Because the term really hinges around the
small size of the antenna it has been used to describe both one-way and
interactive systems. Specifically, we in the industry, isolate
television broadcast receivers because counting these as well would
simply distort the numbers in the marketplace, but data, audio and, to
some extent, voice systems are included. Generally, these systems
operate in the Ku-band and C-band frequencies. As a rule of thumb C-band
(which suffers less from rain attenuation, but requires larger antennas)
is used in Asia, Africa and Latin America whilst Ku-band (which can use
smaller antennas, but suffers from rain fade in a monsoon-like downpour)
is used in Europe and North America. Typically, interactive Ku-band
antenna sizes range from 75 centimetres to 1.8 metres and C-band from
1.8 metres to 2.4 metres. One way systems can use antennas as small as
45 centimetres.
- What about one-way systems?
- One-way or broadcast systems rely on a
transmitting station which transmits one or more carriers to the
satellite which re-broadcasts the signal over its coverage area. All
receive-only VSATs under the satellite footprint can then receive the
signal or the user/operator is able to define groups of VSATs from one
to all on the network. Broadcast systems are used for data and audio.
The most popular application for data is the transmission of financial
feeds - Reuters, Telerate and KnightRidder are good examples of
companies with large data broadcasting networks - however, there are
many other uses, such as software downloads, file transfers,
transmission of press agency news items (with pictures) and the
broadcast of paging messages for terrestrial transmission to the pagers
themselves.
- So what is an interactive VSAT?
- Interactive VSAT systems come in two
main network topologies - star and mesh. The former tends to be based
either on a shared access scheme (TDM/TDMA), which is designed to
support transactional processing applications, broadband internet access or,
for intensive use, on a dedicated link
(the satellite equivalent to a leased line). The latter sometimes uses
an access scheme whereby links are set-up and torn-down on request to establish a direct
link between two sites on a demand assigned basis. DAMA can be used in a
mesh or star configuration with mesh systems
initially designed to support corporate and public network
telephony links. The past ten years have seen them increasingly used to serve high data rate
services, such as file downloads, at rates typically ranging between 64 kbps
and 2 Mbps, although much greater rates are possible with larger
antennas.
- This industry is full of acronyms -
what do they mean?
- This gets complicated, but
here is an extensive list of acronyms, terms,
abbreviations and data rates for your reference. Like any
other industry, it seems as though you will never be able to understand,
but its not that bad and it doesn't take long to get the basics.
- What about statistics?
- The VSAT market has been going since
the early 1980s and the launch of the first one-way VSAT system by
Equatorial of California. Towards 1985 the first interactive star
systems began to be seen and it wasn't until 1989 that the first mesh
telephony products were really sold. COMSYS is recognised as the leader
in tracking the size and trends of the market.
- What does a network look like?
- VSAT networks come in various shapes
and sizes ranging from star data system users with one site connected to
an operator's shared hub to many thousands based on a dedicated facility
located at their own site. Mesh systems have traditionally been somewhat
smaller in size than star systems - 5 to 30 sites used to be a good rule
of thumb - but the average size of orders has risen as prices have come
down and some rural telephony networks now comprise as many as several
hundred or even thousands of sites. This is what
they look like. By the way, this link contains some large-ish
(30k) graphics.
- What kind of companies use VSAT
systems?
- You name it really, car dealerships,
gas stations, lottery systems, banks, insurance companies, drug stores,
general stores, supermarkets, healthcare companies, manufacturers,
couriers, hotel chains, car rental businesses, food manufacturers, heavy
industries, mines, electrical utilities, oil and gas pipelines, energy
production and exploration, timber companies, plantations, maritime
shipping fleets, various
government departments and agencies ....... any others you can think of,
just add to the list. Click here to see
some examples of both major and minor networks from all over the world.
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