Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around 20 kHz to around 300 GHz. This is roughly between the upper limit of audio frequencies and the lower limit of infrared frequencies; these are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves. Different sources specify different upper and lower bounds for the frequency range.
There is only one electromagnetic spectrum, but by using different carrier frequencies, numerous RF devices can coexist. The world of RF is a world of frequencies. This is true within a single system or even a single PCB, considering that one RF design may involve signals in multiple frequency ranges. But at this point we want to look at the broad context in which a particular RF system exists; the name we give to this concept is “the electromagnetic spectrum.”Read More