Analog Communications Mock Test 1

10%

Question 1 of 10

1. Calculate power in each sideband, if power of carrier wave is 176W and there is 60% modulation in amplitude modulated signal?

13.36W

67W

52W

15.84W

Question 1 of 10

Question 2 of 10

2. What do you understand by high level AM?

No need to boost the carrier and modulating signal

Modulation is done at high power of carrier and modulating signal

Output power is low

Modulation is done at low power of carrier and modulating signal

Question 2 of 10

Question 3 of 10

3. Which devices did we use for AM Demodulation?

Only quadrature detector

Ratio detector and Slope detector

Envelope detector and Square law demodulator

PLL detector and Foster-Seeley discriminator

Question 3 of 10

Question 4 of 10

4. An AM signal is represented by x(t) = (30 + 2Sin(700πt)) Cos(2πt x 10²t)V. Find the total power of amplitude modulated wave?

453W

789W

451W

675W

Question 4 of 10

Question 5 of 10

5. A modem is classified as low if speed of data rate is ________

upto 500bps

upto 400bps

upto 200bps

upto 600bps

Question 5 of 10

Question 6 of 10

6. What is the role of the transmitter in the communication system?

to produce radio waves to transmit data

to convert one form of energy into other

to decode a signal to be transmitted

to detect and amplify information signal from the carrier

Question 6 of 10

Question 7 of 10

7. The minimum height of antenna required for transmission in terms of ʎ is ________

^ʎ⁄₄

^3ʎ⁄₂

2ʎ

Question 7 of 10

Question 8 of 10

8. AM broadcast station transmits modulating frequency upto 6KHz. If transmitting frequency is 810KHz, then maximum and lower sidebands are ________

822KHz and 816KHz

916KHz and 904KHz

816KHz and 804KHz

826KHz and 804KHz

Question 8 of 10

Question 9 of 10

9. Process of recovering information signal from received carrier is known as ________

Selectivity

Demodulation

Fidelity

Sensitivity

Question 9 of 10

Question 10 of 10

10. Frequency components of an AM wave are?

Carrier frequency (ω_c) with amplitude A

Lower side band (ω_c + ω_m) having amplitude ^mA⁄₂

Carrier frequency (ω_c/2) with amplitude A

Upper side band (ω_c - ω_m) having amplitude ^mA⁄₂

Question 10 of 10