As a rule of thumb, often termed as Carson’s Rule, 98% of the signal power in FM is contained within a bandwidth equal to the deviation frequency, plus the modulation frequency-doubled. Carson’s rule: Bandwidth of FM BWFM = 2 [ Δf + fm ].

## What is Carson’s rule for FM bandwidth?

In telecommunication, Carson’s bandwidth rule defines **the approximate bandwidth requirements of communications system components for a carrier signal that is frequency modulated by a continuous or broad spectrum of frequencies** rather than a single frequency.

## What is Carson’s rule formula?

Note 1: The Carson bandwidth rule is expressed by the relation **CBR = 2( f + f _{m})** where CBR is the bandwidth requirement, f is the carrier peak deviation frequency, and f

_{m}is the highest modulating frequency.

## What is the difference between FM and PM?

In FM, the **frequency derivation is proportional to the modulating voltage only**. In PM, the frequency derivation is proportional to the modulating voltage as well as modulating frequency. … Amplitude of FM wave is constant. Amplitude of PM wave is also constant.