Frequency Division Multiple Access (FDMA)
Wednesday, December 23rd, 2009FDMA has been the most frequently used technique primarily because it is the simplest to implement. With FDMA, each earth terminal accessing a satellite merely transmits on a different frequency. The available bandwidth is subdivided into smaller frequency bands, or subchannels, in which each subchannel is assigned to a specific user.
Polar Orbit
Saturday, September 12th, 2009A polar orbit is any orbit, which has an inclination of or very close to 90 degrees. A satellite in a polar orbit passes over (or very close to) the north and south poles on every pass.
Geosynchronous Orbit
Saturday, August 29th, 2009In a geosynchronous orbit, a satellite’s motion is synchronized with an area of the earth below it and centered on the equator. The satellite completes an orbit in the same 24-hour period as the earth’s rotation. From the earth, such a satellite appears to be stationary in the sky.
A satellite with this orbit is considered to be in a high altitude orbit at approximately 13,000 to 23,000 miles above the surface of the earth. A geosynchronous orbit is said to be inclined when the plane of the satellite’s orbit is at an angle to the plane of the earth’s equator. For inclinations other than zero degrees, a geosynchronous satellites ground trace will be a figure eight straddling the equator.
Molniya Orbit
Saturday, August 15th, 2009The Molniya orbit is a high elliptical type of orbit first used by Russia. A satellite in such an orbit is semi- synchronous, spending about six to eight hours of every 24 hours over a particular region of the earth. This is ideal for communications satellites used to provide coverage in the extreme northern latitudes where access to geostationary satellites can be difficult. There are systems of other satellites in Molniya orbits in which ground systems switch among three or four such satellites in order to receive continuous coverage.
Top 10 Questions to Ask Your Satellite Internet Service Provider
Monday, October 13th, 2008Author: Bob Exum
If you are a corporation in search of disaster recovery networking solutions, a first responder who may need connectivity from anywhere at any time, or you simply need broadband internet connectivity from remote locations you have probably considered that satellite may be your only reliable option. In the midst of a disaster many businesses and first responders may find themselves without communications of any kind due to the loss of terrestrial infrastructures, or the lack of it ever existing in the first place.
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