____ modulation, which is commonly employed in contemporary modems, uses each signal change to represent 4 bits.
a. Quadrature amplitude
b. Quadrature frequency
c. Quadrature noise
d. Quadrature phase
Answer: A
____ modulation, which is commonly employed in contemporary modems, uses each signal change to represent 4 bits.
a. Quadrature amplitude
b. Quadrature frequency
c. Quadrature noise
d. Quadrature phase