Satellite Communications

Satellite Communications

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Description of Satellite Communications

Some of the main reasons for using satellite communications a your main method for connecting are:

  • you are too far from the terrestrial infrastructure (no alternative supply) - in the mountains/ jungles, and islated islands of the world or maybe just the suburbs of a major city.
  • you need more speed that the other available alternatives.
  • it might even be cheaper (though not often)

Terrestrial infrastructure may be good, but in many countries, incumbant telecommunications companies control access and prices ae still very high. Other countries have reasonable bandwidth within the country, but very poor capacity to the outside world. (At the end of 2002, only six of the 54 countries in Africa had more international bandwidth than the average American home has now! - Source: Telegeography.com)

 

Satellite Phones

Used for phone calls as well as email. Way to expensive for web surfing.

BGAN / RBGAN

Light, mobile data terminals. Affordable to buy, expensive to run!

The original incarnation was as RBGAN (Regional Broadband Global Area Network), operated by Inmarsat in cooperation with Thuraya, and covering 99 countries from west Europe through to China and the Actic circle down to about Northern Kenya.

RBGANs are about the size and weight of a laptop, and provide up to 144kbps connectivity from anywhere within the coverage area (with a clear view to the satellite). With data costs running about 7-9/Mb, it is fine for text-only email and IM, but not great for surfing or iTunes downloads unless you have a huge budget.

The units run off a Lithium-ion battery, car or mains electrical adapter and can connect to computers by Ethernet, USB or Bluetooth. There are drivers fro Windows and Mac OSX.

Recently the coverage area has expanded and will soon be global. New equipment will support up to 432kbps data speed. Latest info can be found at http://broadband.inmarsat.com/.

This technology certainly has its place, especially in disaster response, where it can be deployed very quickly almost anywhere. Despite its significant running costs, it can also be easily justified in certain conditions. I heard one organization spent $18,000 in one month sending high quality photos back to HQ from a disaster scene, and rasied several million dollars for ongoing program support as a result.

If you want to know more, you could contact Mike Bizub at Bizub Communications ( http://www.bizubcomm.com ) They have helped out a lot of missions and humanitarian organizations.

1-way Satellite Broadband Internet

Satellite down link, phone uplink via ISP.

 

2-way Satellite Broadband Internet

VSAT satellite

VSAT stands for Very Small Aperture Terminals, and is generally used to refer to dish antennas with a diameter of less than 3m, whereas in the early days of satellite communications, dishes of 30m or more were common.

VSAT systems generally use geostationary satellites which are located at 2-3 degree intervals about 22,000 miles above the equator.

There are two main frequency bands used for commercial VSAT services : Ku band and C band. In broad ters, Ku can make do with smaller dishes (typically 1.2-1.8m), is normally availabe in high population density areas, but can lose signal during heavy rain. C band generally has wider availability, needs largr dishes (1.8m-2.4m commonly) but it impervious to heavy rain.

VSATs can be deployed in a fixed position, or on a stabilized platform on board ships (e.g. Mercy Ships / O.M.) or vehicles.

VSAT systems are very scalable. You can get a bandwidth package that will be fine for a couple of people in a small mission station, or you can run a small nation using VSAT. (All telecomms for the island nation of Tonga are via VSAT, controlled out of Long Island, NY. That's all phones, faxes, Internet, cell phones, etc.)

Buying VSAT services is definitely something that you need to take time over. It is NOT like buying a DSL connection at home. The common three questions we hear are: how much is the equipment?, how fast is it? and how much does it cost per month? You need to know much more and ask many more questions, or else you are likely to get a cheap solution that doesn't perform. There are some documents you can download from http://www.drasticom.org/resources.htm which should help you get an appreciation of some of the things you should consider. This is not meant to be "sales literature," but educational information. If you think it is biased, listen to some other suppliers too. At least you might ask some better questions before you buy!

Amateur Radio Satellites

How is Satellite Communications used in Missions?

You can use a fast satellite internet connection for anything you can use any other fast connection for...

  • Communication , coordination and collaboration with colleagues worldwide.
    • Email, browsing, IM
    • Voice over IP, video conferencing (from skype through to professional h323 polycomm etc.)
    • Podcasting, blogging
    • music and video downloads
  • Remote control and support of desktops and servers
  • Distance Education
  • Telemedicine
  • Evangelism
  • Discipleship / Mentoring
  • Economic development and business

Etc

Issues with Satellite Communications

VSAT usage is generally licensed within in country, and the ease with which licenses can be obtained varies greatly. Unfortunately, many developing countries still see VSAT as a cash cow. While their politicians are off at conferences complaining about the effects of the Digital Divide on their economies, their Telecoms licensing people are busy extracting unreal licesning costs from anyone willing to pay.

Some countries offer helpful discounts to NGOs, or even allow free licenses. One country charges $42,000 a year for its licenses!

Different implementations and solutions using Satellite Communications

 

Original page: http://www.missiontech.info/wiki/Satellite_Communications
from the MissionTech Wiki created by the International Conference on Computers and Missions

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