Principles Of Communication

Question 1

What is the formula for calculating the bandwidth of a communication channel?

Answer 1

Bandwidth = Highest Frequency - Lowest Frequency

Question 2

True or False: The Nyquist theorem states that the maximum data rate of a channel is determined by its bandwidth and the signal-to-noise ratio.

Answer 2

False

Question 3

Fill in the blank: The formula for the signal-to-noise ratio (SNR) is __________.

Answer 3

SNR = 10 * log10(Psignal / Pnoise)

Question 4

What does the term ‘modulation’ refer to in communication systems?

Answer 4

Modulation refers to the process of varying a carrier signal in order to transmit information.

Question 5

What is the formula for calculating the maximum data rate using Shannon’s theorem?

Answer 5

C = B * log2(1 + S/N)

Question 6

True or False: Amplitude modulation (AM) varies the amplitude of the carrier wave to convey information.

Answer 6

True

Question 7

What is the purpose of a filter in a communication system?

Answer 7

To remove unwanted frequencies and allow desired signals to pass through.

Question 8

What is the formula for calculating the power of a signal?

Answer 8

Power = Voltage^2 / Resistance

Question 9

Multiple Choice: Which of the following is a type of digital modulation? A) Frequency Modulation B) Amplitude Modulation C) Phase Shift Keying D) All of the above

Answer 9

C) Phase Shift Keying

Question 10

Fill in the blank: The formula for the bit error rate (BER) is __________.

Answer 10

BER = Number of Bit Errors / Total Number of Transmitted Bits

Question 11

What is the function of a transmitter in a communication system?

Answer 11

To convert information into a signal suitable for transmission.

Question 12

What is the formula for calculating the effective radiated power (ERP)?

Answer 12

ERP = Transmitter Power * Antenna Gain

Question 13

True or False: Frequency division multiplexing (FDM) allows multiple signals to be transmitted simultaneously over the same channel.

Answer 13

True

Question 14

What is the formula for calculating the delay spread in a multipath communication channel?

Answer 14

Delay Spread = Tm - To

Question 15

Multiple Choice: Which of the following factors does NOT affect the performance of a communication system? A) Noise B) Bandwidth C) Distance D) Color of the equipment

Answer 15

D) Color of the equipment

Question 16

What is the formula for calculating the voltage gain in a circuit?

Answer 16

Voltage Gain = Vout / Vin

Question 17

Fill in the blank: The formula for calculating the total noise power in a system is __________.

Answer 17

N_total = kTB

Question 18

What is the definition of ‘modulation index’ in frequency modulation?

Answer 18

Modulation index is the ratio of the frequency deviation to the modulating frequency.

Question 19

True or False: Digital signals can take on a continuous range of values.

Answer 19

False

Question 20

What is the formula for calculating the rise time of a signal?

Answer 20

Rise Time = 0.35 / Bandwidth

Question 21

What does ‘QAM’ stand for in digital communication?

Answer 21

Quadrature Amplitude Modulation

Question 22

Fill in the blank: The formula for calculating the channel capacity is __________.

Answer 22

C = B * log2(1 + S/N)

Question 23

What is the purpose of error correction in communication systems?

Answer 23

To detect and correct errors that occur during data transmission.

Question 24

Multiple Choice: Which modulation technique is typically used for video transmission? A) AM B) FM C) QAM D) All of the above

Answer 24

D) All of the above

Question 25

What is the formula for calculating the noise figure (NF) of a system?

Answer 25

NF = (S/N input) / (S/N output)