# Modulation and Coding Trade-off MCQ [Free PDF] – Objective Question Answer for Modulation Coding Trade-off Quiz

1. QPSK is a composite of

A. Two BPSK
B. Three BPSK
C. Two FSK
D. Two M-ary PSK

QPSK is effectively a composite of two BPSK signals transmitted on orthogonal components of the carrier.

2. The IF transmission bandwidth of MFSK is

A. M/T
B. T/M
C. 2M/T
D. M/2

In non-coherent orthogonal MFSK modulation, the IF transmission bandwidth is WIF = M/T.

3. The bandwidth efficiency of MFSK is

A. M/log2M
B. log2M/M
C. M/log10M
D. log10M/M

For non-coherent orthogonal MFSK modulation, the bandwidth efficiency is R/W=log2M/M.

4. The bandwidth efficiency increases as M increases.

A. True
B. False

The bandwidth efficiency decreases as M increases.

5. The bandwidth efficiency of QFSK is _______ that of BFSK.

A. Greater than
B. Less than
C. Equal to
D. None of the mentioned

The bandwidth efficiency of QPSK is equal to that of the BFSK.

6. Which modulation is the most efficient one?

A. BPSK
B. BFSK
C. QPSK
D. QAM

Of all the modulation shown, QAM is the most bandwidth-efficient one.

7. The primary communication resource is

A. Transmitted power
C. Efficiency
D. None of the mentioned

The primary communication resources are transmitted power and channel bandwidth.

8. Greater the redundancy lesser is the bandwidth expansion.

A. True
B. False

Within the same block size, the code with greater redundancy requires more bandwidth expansion.

9. Which modulation scheme uses nonlinear transponders?

A. MSK
B. Offset QPSK
C. MSK & Offset QPSK
D. None of the mentioned

Offset QPSK and MSK are two examples of constant envelope modulation schemes that are attractive for systems using non-linear transponders.

10. Which modulation requires more bandwidth?

A. QPSK
B. OQPSK
C. BPSK
D. BFSK