Topics:
Satellite
communication is the method of transporting information from one place to
another using a communication satellite in orbit around the Earth. Watching the
NBA basketball every weekend with your friends would have been impossible
without this. A communication satellite is an artificial satellite that
transmits the signal via a transponder by creating a channel between the
transmitter and the receiver located at different locations on the Earth.
Telephone, radio, television, internet, and military applications use satellite communications. Believe it or not, more than 2000 artificial satellites are hurtling around in space right above your heads.
How do Satellite Communications Work?
The communication satellites are similar to the space mirrors that help us in bouncing the signals such as radio, internet data, and television from one side of the earth to another. There are three stages that are involved which explain the working of satellite communications. These are:
- Uplink
- Transponders
- Downlink
Let’s consider an example of signals from a television. In the first stage, the signal from the television broadcast on the other side of the earth is first beamed up to the satellite from the ground station on the earth. This process is known as uplink.
The second stage involves transponders such as radio receivers, amplifiers, and transmitters. These transponders are used for boosting the incoming signal and to change their frequency so that the outgoing signals are not altered. Depending on the incoming signal sources, the transponders vary.
The final stage involves a downlink in which the data is sent to the other end of the receiver on the earth. It is important to understand that usually there is one uplink and multiple downlinks.
The frequency range in satellite communications is between 1 GB and 40 GB. Most of the frequency bands at which they broadcast are not intended for the distribution of television and radio broadcasts but for other purposes: military, naval communications (Inmarsat satellites), meteorology satellites (Eumetsat), and more. All satellites use an uplink and a second (downlink) frequency that lowers the information to consumers on Earth.
Satellite Ground Station
A ground station, Earth station, or Earth terminal is a terrestrial radio station designed for extraplanetary telecommunication with spacecraft or reception of radio waves from astronomical radio sources. Earth stations communicate with spacecraft by transmitting and receiving radio waves in the super-high frequency (SHF) or extremely high frequency (EHF) bands (e.g. microwaves). When a ground station successfully transmits radio waves to a spacecraft (or vice versa), it establishes a telecommunications link. A principal telecommunications device of the ground station is the parabolic antenna.
Specialized satellite Earth stations are used to telecommunicate with satellites — chiefly communications satellites. Other ground stations communicate with crewed space stations or uncrewed space probes. A ground station that primarily receives telemetry data, or that follows space missions, or satellites not in geostationary orbit, is called a ground tracking station, or space tracking station, or simply a tracking station.
The Ella Valley Satellite Station is a satellite relay station. located in the Ella Valley.