Question

There are two baseband message signals m1(t) and m2(t), with bandwidth B1 and B2, respectively. What is the bandwidth of their corresponding QAM

modulated wave?
Select one:
a. max(2B1, 2B2)
b. 2(B1+B2)
c. B1+B2
d. max(B1,B2)

Answer 1

The bandwidth of a QAM-modulated wave for two baseband signals with bandwidths B1 and B2 is double the sum of the individual bandwidths, which is 2(B1+B2).

Step-by-step explanation:

The bandwidth of the corresponding Quadrature Amplitude Modulated (QAM) wave for two baseband message signals m1(t) and m2(t) is found by doubling the sum of their respective bandwidths. In QAM, each signal is modulated onto a carrier wave; one is modulated in-phase, while the other is modulated in quadrature (90 degrees out of phase). This allows two signals to be transmitted over the same frequency band. Therefore, the answer to the question of what the bandwidth of their corresponding QAM-modulated wave is b. 2(B1+B2).