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Advantages of Satellite Communication

Satellite communication is a system whereby large volumes of data can be transmitted or “uplinked” from a transmitting station to a satellite positioned in geostationary orbit 36,000 km above the equator, then “downlinked” in a single transmission to multiple receiving stations on Earth. It is the ideal option for transmitting a large volume of data to myriad destinations instantly.

Communication using satellites offers a number of advantages: wide-area multicasting, flexibility and high data capacity. This form of communication also offers the added advantage of “disaster tolerance,” since it can ensure a communication network even after a natural disaster.

Wide-area multicasting

The benefits of being able to broadcast to multiple targets spread over a wide area are evident when transmitting a large volume of data simultaneously from one location to innumerable receiving stations (“n” in the figure below).

･Transmitting station Sends data to the satellite via proprietary transmission equipment or transmission facilities of a telecom carrier’s satellite division. ･Satellite Amplifies the data signal sent from the transmitting station and sends it back to the receiving station. ･Receiving station Receives data from the satellite.

Broadly speaking, there are two different ways in which satellite communications can be used for data broadcasting. One is “real-time broadcasting,” whereby data is broadcast all at once, as described above. The other is “storage-based broadcasting.” “Real-time broadcasting” is when live coverage of an event or similar data sent from the transmitting station is viewed on a terminal such as a television or PC as soon as it arrives at the receiving station. “Storage-based broadcasting” is when the data sent from the transmitting station is stored on a server at the receiving station to be accessed by users as and when required.

Flexibility

Use of a vehicle-mounted or mobile receiving station enables a communication link to be set up quickly in any location. Satellites offer an easy means of communication in places where landlines cannot easily be installed, in mountainous areas, and in other places beyond the reach of regular wireless communication signals. Satellite-based communication is also ideally suited to mobile communications utilizing aircrafts and ships.

Disaster tolerance

Communications satellites offer the additional benefit of being highly resistant to the impact of natural disasters on the ground such as earthquakes or tsunamis. They ensure a stable communications link that connects reliably even during a disaster.

High data capacity