Have you ever wondered how the many satellites in the sky work and track your mobile phones? What about the history of how they came about?
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- Technology explained: How satellites work step by step
- The History of How Satellites Began to be Used For Mobile Phones
Satellites play an incredibly important role in providing the means by which we communicate in the modern world. They are the instrumental technology used to ensure we receive coverage for mobile phones wherever we are in the world and at any time we need to make a call or transmit information.
Since their inception, satellites have progressed in a way that has allowed enormous leaps in the technological development of mobile phones and have played a vital part in creating the current generation of smartphones and many of the features we take for granted today.
Without them, we wouldn’t be able to browse the internet on our phones, send picture messages or make long distance phone calls – they will certainly continue to play an important role in future developments. To help give you a better understanding of mobile communication networks, we have compiled this guide on how satellites work.
Technology explained: How satellites work step by step
The process of transmitting data and information via satellites begins on Earth, with any device capable of transmitting radio signals to satellites. These are known as ‘Earth stations’ (image above) and they send the radio signals up to the satellites through the use of antenna.
Technically, you can relay a signal off any object in space, such as the Moon, but to do this you would need an incredibly strong signal. In order to minimize the power necessary to send a signal successfully, satellites have been put into orbit in various networks. These satellites are sent the signal, known as an ‘uplink,’ and then return a signal, known as the ‘downlink.’
Once the satellite Uplink signal is received
Once the radio signal reaches the satellite, it can be bounced off and sent back down to another Earth station in another location. However, modern satellites no longer just bounce back signals, but amplify them, making the signal stronger than it was when received by the satellite. Usually, the satellite will also convert the radio signal from one frequency to another. This prevents the uplink and downlink signals being confused.
In this way, satellites facilitate communication across vast distances that would otherwise be impossible. When arranged in networks, satellites also have the capability to relay signals to each other, expanding the amount of coverage possible by using satellites positioned above every part of the globe.
Each Earth station will often also perform a variety of specialised functions that are necessary to control the satellites or provide services. For instance, some will deliver visual or audio signals to the satellite, which are then beamed across the globe to those watching or listening to digital devices. On the other hand, downlink Earth stations can be used to allow satellites to connect to the internet; they are often called ‘hub’ or ‘gateway’ stations.
Spot beam satellite footprints
The area serviced by any particular satellite is commonly known as the satellite’s footprint and is determined by the range and strength of the signal it can provide. Modern satellites now have the capability to shape their footprint, limiting the area which receives its signal. One of the main ways in which they do this is through the use of ‘spot beams.’ Spot beams concentrate the power of a signal, usually through a high-gain antenna, so that the footprint is reduced in size and scope. This technology is used to transmit region-specific content, such as local news, to areas that need it.
On a last note, ever wonder how satellites track your location? Well they do it through triangulation of your location from 3 antenna using GPS as seen below!
The History of How Satellites Began to be Used For Mobile Phones
In August 1964 INTELSET (the International Telecommunications Satellite Organisation), an inter-governmental organisation, was set up with a charter to design, construct, establish and maintain the operation of a global commercial communications system. It was a partnership between 11 nations and their first satellite, Intelsat I (or the Early Bird as it was otherwise known), was put into geostationary orbit in 1965. By 2001, INTELSAT contained over 100 members and provided services to over 600 Earth stations in more than 149 countries. However in 2001, under pressure from private satellite company lobbyists, the U.S. government moved to privatise the company. It now operates under the name Intelsat Ltd. and continues to provide satellite service around the world.
But obviously it didn’t stop there. The Intersputnik International Organisation of Space Communications, otherwise known as Intersputnik, was founded in 1971, as a response to INTELSAT. It was created in Moscow by the Soviet Union and eight other former socialist stats – to develop and promote the common use of communication satellites.
That’s when things finally started going in a mobile direction. Marisat satellites were then the first mobile communications satellites in operation, and provided service to ships and boats around the world. They gave permission to the U.S. Navy and other commercial ventures to utilise their satellites in any of the main oceanic regions.
These are three of the most important satellite networks in the history of the technology. As you can see, most organisations attempting to put satellites into orbit and create a global communications network started out as inter-governmental projects. However as the economy, politics and culture has changed over the last few decades, the satellite industry has become more and more privatised and companies, rather than governmental organisations, now own most of the world’s satellite communication networks. One thing we can be sure of is that satellites will be an integral part of any new communication technology emerging in the near future.