A microwave system is similar to the general working principles of communication system The data received from another device. Then the process to convert the data to be radio and sent to the receiver.(usually the frequency about 300MHz-100GHz) depends on the Central Committee oversight (FC: Business CommunicationThe Federal Communication Commission), which is like a radio station. To ask permission to use the frequency. In order not to disturb the other signals such as communication with the aircraft and microwave system. Etc.
.In the radio frequency used, starting from the 300 kHz up. If from 30 Mega hertz to 300 Mega Hertz is called. She F V (VHF) from 300 Mega hertz to 30 Giga Hertz is called Yu Hesh f (UHF)
.System VHF (Very High Frequency)
.The system is a system VHF spectrum used in radio and television broadcasting business, communication distance of near frequency 30 - 300 MHz. The first system used in the television signal. 4 Bang Khun Prom send a signal.Signals from the ground station (Terestrial Station) go far, hundreds of kilometers. Receiver with antenna of general, the system is open to the public, or called TV (Free TV), such as channel, 3,, and 5 7 9 11
system UHF (Ultra High Frequency)
.UHF system is a system that is found with the ITV including aviation, communication and other communication distance with the signal in the frequency range of Analog 300 MHz. Due to 3 GHz signals have very high frequency. That could signal distance.The receiver can use common antenna.
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