

MCQOPTIONS
Saved Bookmarks
This section includes 23 Mcqs, each offering curated multiple-choice questions to sharpen your Wireless Mobile Communications knowledge and support exam preparation. Choose a topic below to get started.
1. |
Which of the following is not a detection technique used for detection of π/4 QPSK signals? |
A. | Baseband differential detection |
B. | IF differential detection |
C. | FM discriminator detection |
D. | Envelope detection |
Answer» E. | |
2. |
QPSK provides twice the bandwidth efficiency and _______ energy efficiency as compared to BPSK. |
A. | Twice |
B. | Half |
C. | Same |
D. | Four times |
Answer» D. Four times | |
3. |
QPSK has ________ the bandwidth efficiency of BPSK. |
A. | Twice |
B. | Same |
C. | Half |
D. | Four times |
Answer» B. Same | |
4. |
The energy efficiency of DPSK is _________ to coherent PSK. |
A. | Superior |
B. | Same |
C. | Zero |
D. | Inferior |
Answer» E. | |
5. |
In DPSK system, input signal is differentially encoded and then modulated using a ________ modulator. |
A. | Amplitude |
B. | Frequency |
C. | BPSK |
D. | QPSK |
Answer» D. QPSK | |
6. |
By applying cos(2πft), BPSK signal is equivalent to ________ |
A. | Double sideband suppressed carrier amplitude modulated waveform |
B. | Single sideband suppressed carrier amplitude modulated waveform |
C. | Frequency modulated waveform |
D. | SSB amplitude waveform |
Answer» B. Single sideband suppressed carrier amplitude modulated waveform | |
7. |
In BPSK, the ________ of constant amplitude carrier signal is switched between two values according to the two possible values. |
A. | Amplitude |
B. | Phase |
C. | Frequency |
D. | Angle |
Answer» C. Frequency | |
8. |
In linear modulation technique __________ of transmitted signal varies linearly with modulating digital signal. |
A. | Amplitude |
B. | Frequency |
C. | Phase |
D. | Angle |
Answer» B. Frequency | |
9. |
THE_ENERGY_EFFICIENCY_OF_DPSK_IS________TO_COHERENT_PSK.?$ |
A. | Superior |
B. | Same |
C. | Zero |
D. | Inferior |
Answer» E. | |
10. |
QPSK provides twice the bandwidth efficiency and ____ energy efficiency as compared to BPSK.$ |
A. | Twice |
B. | Half |
C. | Same |
D. | Four times |
Answer» D. Four times | |
11. |
QPSK has _____ the bandwidth efficiency of BPSK.$ |
A. | Twice |
B. | Same |
C. | Half |
D. | Four times |
Answer» B. Same | |
12. |
Which of the following is not a detection technique used for detection of π/4 QPSK signals?$ |
A. | Baseband differential detection |
B. | IF differential detection |
C. | FM discriminator detection |
D. | Envelope detection |
Answer» E. | |
13. |
QPSK signals perform better than OQPSK in the presence of phase jitter. State whether True or False. |
A. | True |
B. | False |
Answer» C. | |
14. |
The bandwidth of OQPSK is _______ to QPSK. |
A. | Identical |
B. | Twice |
C. | Half |
D. | Four times |
Answer» B. Twice | |
15. |
What is the full form of OQPSK? |
A. | Optical Quadrature Phase Shift Keying |
B. | Orthogonal Quadrature Pulse Shift Keying |
C. | Orthogonal Quadrature Phase Shift Keying |
D. | Offset Quadrature Phase Shift Keying |
Answer» E. | |
16. |
In DPSK system, input signal is differentially encoded and then modulated using a _____ modulato? |
A. | Amplitude |
B. | Frequency |
C. | BPSK |
D. | QPSK |
Answer» D. QPSK | |
17. |
DPSK uses coherent form of PSK. State whether True or False. |
A. | True |
B. | False |
Answer» C. | |
18. |
BPSK uses non-coherent demodulator. State whether True or False. |
A. | True |
B. | False |
Answer» C. | |
19. |
By applying cos(2πft), BPSK signal is equivalent to ________$ |
A. | Double sideband suppressed carrier amplitude modulated waveform |
B. | Single sideband suppressed carrier amplitude modulated waveform |
C. | Frequency modulated waveform |
D. | SSB amplitude waveform |
Answer» B. Single sideband suppressed carrier amplitude modulated waveform | |
20. |
In BPSK, the _____ of constant amplitude carrier signal is switched between two values according to the two possible values. |
A. | Amplitude |
B. | Phase |
C. | Frequency |
D. | Angle |
Answer» C. Frequency | |
21. |
Which of the following is not a linear modulation technique? |
A. | OQPSK |
B. | π/4 QPSK |
C. | FSK |
D. | BPSK |
Answer» D. BPSK | |
22. |
Linear modulation techniques are not bandwidth efficient. State whether True or False. |
A. | True |
B. | False |
Answer» C. | |
23. |
In linear modulation technique, ______ of transmitted signal varies linearly with modulating digital signal. |
A. | Amplitude |
B. | Frequency |
C. | Phase |
D. | Angle |
Answer» B. Frequency | |