Communication satellites power our insatiable appetite for data on the go and can connect people in different locations anywhere on Earth, with voice, image, video and broadband internet.
Today, over 1.4 billion smartphones are in use. This equates to one in every five people on our planet accessing ‘apps’ and data on the move. If we add TV, radio and the internet, then telecommunications are as integral to our daily lives as access to fuel and water.
They link ships crossing the oceans, provide communications for aircraft, connect people in remote areas not serviced by cellular or fibre optic networks, and enable disaster response teams to keep in touch when ground-level infrastructure has collapsed.
HOW COMMUNICATION SATELLITES WORK
Communication satellites can connect people in different locations anywhere on Earth.
Communication satellites are essentially relays, allowing information to be passed around the globe via space in a number of ways.
They use 3 types of orbit: GEO, LEO & HEO.
Only three GEO satellites are needed to provide coverage to most of the Earth, the exception being the poles. Once an antenna is pointed at a GEO satellite, a constant connection can be established, making them perfect for streaming data.
(Low Earth Orbit)
LEO satellite constellations can provide continue cover to one location. They are usually multiple satellites moving in and out of sight of a given position at any time.
(High Elliptical Orbit)
HEO satellites can be used to provide constant signal to areas where GEO satellites are unable. They have slow speed at the top of the orbit meaning they can provide coverage to one location for long periods of time.
WHAT KIND OF DATA DOES IT SEND?
The types of data that can be sent via satellite include:
Data transfer rates currently range from 15kbps to 10mbps, though in the future we will see transfer rates around the 30mbps mark, closer to what we are used to for traditional web browsing. Some providers now offer pay monthly tariffs rather than per kb rates, that may be cheaper for constant or heavy data applications.
HOW MUCH DOES IT COST TO SEND DATA?
Sending voice data, images and streaming video all adds up, especially for mobile services. Example costs for mobile services:
- Voice call = typically £0.75/min
- Word document (100kb) = £0.40p
- Image (1mb) = £4.00
- 1 minute video (20mb) = £80.00
Costs for fixed services e.g. satellite TV are much cheaper.
The cost of antennas can range from about £200-£11,000 depending on the size, power and service provider.
WHAT IS A HANDOVER?
When using a constellation to transfer data, there is a point at which a “handover” must occur between two satellites. This can be troublesome for data applications that require a constant connection, such as video streaming. Different transmission types will suit different data types, depending on the service required.
COMMS APPLICATION EXAMPLE
Access to immediate healthcare advice for people who work in remote areas or who have restricted mobility is often of poor quality and coverage.
The Satellite Solution
Whilst the maritime sector has been an early adopter, governments and the land-based medical profession are exploring the potential for telemedicine using satellite telecommunications technology.