What is RF Signal ?
A Radio Frequency signal is an electromagnetic wave that carries information over the air from one point to another.
RF signals starts as an electrical Alternating Current (AC), generated by a transmitter. This AC signal travels through the copper conductor and radiates out of an antenna in the form of electromagnetic wave.
What we see in the below diagram, is how a room would look if we were to have lot of devices emitting RF signals. These are waveforms commonly known as Sine Wave.
RF Spectrum ranges from 3 KHz to 300 GHz.
|1||VLF – Very Low Frequency||3 KHz – 30 KHz||100 km – 10 km|
|2||LF – Low Frequency||30 KHz – 300 KHz||10 km – 1 km|
|3||MF – Medium Frequency||300 KHz – 3 MHz||1 km – 100 m|
|4||HF – High Frequency||3 MHz – 30 MHz||100 m – 10 m|
|5||VHF – Very High Frequency||30 MHz – 300 MHz||10 m – 1 m|
|6||UHF – Ultra High Frequency||300 MHz – 3 GHz||1 m – 100 mm|
|7||SHF – Super High Frequency||3 GHz – 30 GHz||100 mm – 10 mm|
|8||EHF – Extremely High Frequency||30 GHz – 300 GHz||10 mm – 1 mm|
Below diagram would clearly show us how the wave pattern looks with respect to the distance it travels over the air.