Calculation of bandwidth in FM using Carson’s rule
Q. What is the required bandwidth according to the Carson’s rule, when a 100 MHz carrier is modulated with a sinusoidal signal at 1KHz, the maximum frequency deviation being 50 KHz.- Published on 14 Oct 15a. 1 KHz
b. 50 KHz
c. 102 KHz
d. 150 KHz
ANSWER: 102 KHz
According to Carson’s rule, bandwidth of FM is given by 2(Δf+ fm) where Δf is the deviation in frequency and fm is the frequency of sinusoidal signal. The required bandwidth is therefore calculated as
2 * (50KHz + 1KHz)
= 2 * 51 KHz
= 102 KHz