- An object in space called a satellite orbits or revolves around a larger object. Satellites can be either natural (like the moon circling the Earth) or ma10nmade (such as the International Space Station orbiting the Earth).
- An artificial satellite is a manufactured object that has been put into orbit using a rocket. Over 3,000 satellites are currently in orbit around the Earth. The purpose of a satellite determines its size, height, and structure.
- The sizes of satellites vary. Some cube satellites are only 10 cm in size. Some communication satellites feature solar panels that extend additional 50 meters past their 7-meter length. The International Space Station is the biggest man-made satellite (ISS). Its main portion is the size of a huge five-bedroom house, but when solar panels are added, it is the size of a rugby field.
- There are several satellites in orbit carrying out a wide range of tasks. Today, satellite technology is a commonplace tool for international communication, navigation, monitoring, surveying, data collection for weather forecasting, and many more uses.
What is satellite Communication?
- Satellite communication is the use of artificial satellites to provide communication links between various points on Earth in telecommunications. Satellite communications are critical components of the global telecommunications system. Around 2,000 artificial satellites in orbit around the Earth relay analog and digital signals carrying voice, video, and data to and from one or more locations around the world.
- On October 4, 1957, the Soviet Union successfully launched the first artificial satellite, Sputnik 1. Sputnik 1 had a diameter of only 58 cm (23 inches) and four antennas that sent low-frequency radio signals at regular intervals. It flew in an elliptical orbit around Earth, taking 96.2 minutes to complete one revolution. It only lasted 22 days before its battery died and was only in orbit for three months, but its launch sparked the start of the space race between the United States and the Soviet Union.
- In both ground wave and sky wave propagation, the maximum hop or station distance is limited to 1500KM. This limitation is overcome by satellite communication. Satellites are used in this method to communicate over long distances that are well beyond the line of sight.
- Because satellites are located at a certain height above the earth, satellite communication is simple between any two earth stations. As a result, it overcomes the limitation of communication between two earth stations caused by the curvature of the Earth.
Working on Satellite Communication
- Communication satellites are similar to space mirrors that help us bounce signals like radio, internet data, and television from one side of the planet to the other. There are three stages involved in explaining how satellite communications work. They are as follows.
- Uplink
- Transponders
- Downlink
- Consider the following signal from a television. The signal from the television broadcast on the other side of the earth is first beamed up to the satellite from the earth’s ground station in the first stage. This is referred to as uplink.
- Transponders such as radio receivers, amplifiers, and transmitters are used in the second stage. These transponders boost the incoming signal and change its frequency without affecting the outgoing signals. The transponders differ depending on the incoming signal sources.
- The data is then sent to the other end of the receiver on Earth via a downlink in the final stage. It is critical to understand that there is usually one uplink and multiple downlinks.
Services provided by Satellite Communication
Satellite communication services can be classified into two categories.
- One-way Satellite Communication
- Two-way Satellite Communication
One-way Satellite Communication
- One-way satellite communication typically occurs between one or more earth stations via the use of a satellite.
- Communication takes place between the first earth satellite’s transmitter and the second earth satellite’s receiver. The signal is only transmitted in one direction. Some examples of common one-way satellite communication include.
- The radio provides position location services.
- Space operations services include tracking.
- Broadcast satellites are used to provide Internet services.
Two-way Satellite Communication
- Information is exchanged between any two earth stations in two-way satellite communication. It is possible to say that there is point-to-point connectivity.
- The signal is sent from the first to the second earth station, resulting in two uplinks and two downlinks between the earth stations and the satellite.
