This book offers an introduction to existing and soon to be released satellite communication technologies and services. It covers how satellite systems are changing, growth in key satellite markets, key technologies that are used in satellite systems, commercial satellite systems, and provides information on the leading services and their costs for satellite communication.

Each type of satellite system and its technologies have unique advantages and limitations, which offer important economic and technical more....

Sample Diagrams

There are 19 explanatory diagrams in this book

Low Earth Orbit (LEO) System

This Figure shows a LEO satellite system. In this diagram, a portable satellite telephone is communicating with a landline telephone. The satellite telephone communicates with the closest LEO satellite. Because LEO satellites fly very close to the surface of the earth, they go across the visible horizon in approximately 10 minutes in reference to a mobile satellite customer's location. When the first satellite moves out to the horizon, another LEO satellite becomes available to continue the call. However, robust network communications need to be in place to maintain calls (especially data transmission) within this period. Some systems will use satellite diversity to allow talking through more than one satellite at a time, avoiding call "dropouts" from signal blockage.

Global Positioning System Operation

This figure shows a global positioning satellite (GPS) system. This diagram shows how a GPS receive receives and compares the signals from orbiting GPS satellites to determine its geographic position. Using the precise timing signal based on a very accurate clock, the GPS receiver compares these signals from 3 or 4 satellites. Each satellite transmits its exact location along with a timed reference signal. The GPS receiver can use these signals to determine its distance from each of the satellites. Once the position and distance of each satellite is known, the GPS receiver can calculate the position where all these distances cross at the same point. This is the location. This information can be displayed in latitude and longitude form or a computer device can use this information to display the position on a map on a computer display.

Multibeam Satellite Operation

This figure shows a satellite system that uses spatial division multiple access (SDMA) technology. In this example, a single satellite contains several directional antennas. Some of these antennas use the same frequency. This allows a single satellite to simultaneously communicate to two different satellite receivers that operate on the same frequency. Usually beams that are separated by more than two or three half-power beamwidths can use the same frequencies, as shown in the figure.

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