Microwave system use very high frequency radio signals to transmit data through space (wireless communication). Transmitter and receiver of a microwave system mounted on very high towers, and should be travel almost straight line (should be line of sight). This may not be possible for very long distance transmission . Moreover, signal become weaker after traveling certain distance and require power amplification. Microwave system uses repeater at interval of about 25 to 30 km in between transmitting and receiving station. It is placed on tall building to avoid obstacles. It can support 250,000 voice channels simultaneously. It's installation charge is high.
It is of two types :
i) Terrestrial Microwave : A Ground stations that receives microwave signal, amplifies them and pass them on to another station are known as terrestrial microwave station. The distance between stations is between 25 to 30 miles. Parabolic antennas are used to transmit and receive to each other.
ii) Satellite Microwave : Satellite transmission : A satellite is an object build and placed by human in Earth orbit. It is a specialized wireless receiver/transmitter that is launched by a rocks and placed in the orbit around the earth. There are hundreds of satellites currently in operation. They are used for such diverse purpose as weather forecasting., television broadcast, amateur radio communication, internet communication. Hundreds of satellites are now in orbit to handle international and domestic data, and video communication needs.
No comments:
Post a Comment
If you have any doubt, let me know...