Question

In MFSK, R/W

(a) Increases with increase in M

(b) Increases with decrease in M

(c) Decreases with increase in M

(d) Is not dependent on M

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I'm obligated to ask this question of Evaluating Digital Communication System and Allocation of Communication Resources topic in division Modulation and Coding Trade-off of Digital Communications

Answer 1

Right answer is (c) Decreases with increase in M

The explanation: In MFSK, the denominator increases faster as the numerator when M increases. Thus R/W decreases with increase in M.