Satellite Communication

Satellite communication refers to transferring and transporting information from one point to another by utilising a communication satellite revolving in orbit around the Earth. Satellite communication has made things like watching your favourite TV show every weekend with your friends possible. This innovative communication satellite technology can be understood as an artificial satellite that transmits a signal through a transponder. This whole phenomenon is done with the help of a channel created between the transmitter and receivers present at several locations on Earth.

What is Satellite Communication?

Satellite communication is a technology used in telecommunications. It includes using artificial satellites to convey information by forming communication links between different points on Earth. Satellite communication has a vital role in simplifying the global telecommunication system, with approximately 2,000 artificial satellites present in the orbit of Earth. These artificial satellites relay digital and analogue signals that carry voice data and video from different locations globally. 

Components of Satellite Communications

Satellite communication has two crucial components. These two main components of satellite communication are;

The ground assembly

The ground segment consists of several mobiles or fixed reception, ancillary equipment, and transmission.

The space assembly

This consists of the artificial satellite itself.

Traditional artificial satellite communication transmits a signal from the Earth station to an artificial satellite present in orbit. The transmitted signal is then received by satellite, and it amplifies the signal and sends it back to Earth. After receiving the signal on Earth, it is re-amplified using several stations and terminals.

What is a satellite communication system?

A satellite communication system consists of an uplink signal which goes through an input filter. After passing through an input filter, it is sent to an amplifier that amplifies the signal and sends it to the mixer. The mixer separates the amplified signal and the local oscillator signal. This amplified signal is sent to a transponder that encapsulates an input multiplexer, a TWT amplifier, and an output multiplexer. The transporter then sends the signal to a downlink signal received on the other end. 

Requirement of Satellite Communication

There are several ways to communicate and various ways of propagation of waves. However, they have some limitations like ground wave propagation, and skywave propagation can only be done for a certain distance. Ground wave propagation and skywave propagation can cover a maximum distance of 1500 km. This makes up the basic requirement of satellite communication, as it solves the concept of long-distance communication.

Working of Satellite Communication

Now that you have understood the concept of satellite communication. Let’s move to the working of satellite communication and understand how these satellites function as a communication device at such long distances.

The satellites that enable communication resemble the space mirrors that function as bouncing devices to bounce signals such as internet television and radio from one side of the earth to another point on the other side. Satellite communication is done in three stages that explain the functioning of satellite communication. These three stages are:

• Uplink 
• Transponder
• Downlink

Let’s understand the functioning and working of satellite communication with an example of a television signal. 

In the first stage, the television signal broadcasted on the other side of the earth is first sent to the satellite from the stations present on the ground. This process of beating up the signal from the ground station is known as uplinking.

The second stage consists of transponders, including transmitters, amplifiers, and radio receivers. These devices function as a booster for the incoming signal and perform a change in their frequency that eventually prevents the ordering of signals. The transponder varies according to the incoming signal sources.

The third stage involves a downlink device that sends the data to the Earth, where a receiver receives the signal. The important point to understand here is that there is only one uplink device, whereas there can be multiple downlink devices.

Satellite Communication categories

Satellite communication services are divided into two categories, namely;

• Two-way satellite communication services
• One way satellite communication services

The one-way satellite communication generally takes place among multiple or one Earth station. The communication is done with the transmitter present on the Earth satellite and the receiver, which is present on another Earth satellite. As the name suggests, in one way, satellite communication, the transmission of the signal is done in a single direction. Examples of one-way satellite communication are

• Internet services
• Tracking
• Position location services

The two-way satellite communication involves exchanging information between two Earth stations with point-to-point connectivity. Into the satellite communication, the transmitted signal from the first Earth station is done in a manner that involves two uplinks and two download links between the Earth stations and the satellites.

Conclusion

Satellite communication is an innovative method of communication that helps transport information from one point to another using communication satellites present in the orbit of Earth. There are two components of satellite communication, namely the ground segment and space segment, that complete the function of satellite communication. Satellite communication solves various problems of traditional communication with its easy instalment and advantages like the full control of the network to the user.