Week 2

A full duplex communications system can communicate in both directions but only in one direction at any one time.

• True

• False

The shown system is full duplex.

• True

• False

A multiplexer changes the flow of the signal from parallel to series. True or False?

• True

• False

Pulse Modulation is _______.

• A method of varying the amplitude, frequency, or phase of a pulse train.

• A technique used to increase the bandwidth of a signal.

• A process of converting analog signals to digital signals.

• A method of reducing noise in communication systems.

The monitored triplex redundancy system in aircrafts can survive _______.

• Failure of one component

• Failure of two components

• Complete system failure

• No failure

A voice signal has frequencies between 5 kHz and 20 kHz. What is the bandwidth of this signal?

• 15 kHz

• 25 kHz

• 10 kHz

• 20 kHz

A voice signal has frequencies between 5 kHz and 25 kHz. What is the bandwidth of the AM modulated signal of 30 MHz?

• 20 kHz

• 30 kHz

• 25 kHz

• 5 kHz

Calculate the modulation index of the AM signal if H = 6V and h = 1.5V.

• 0.25

• 0.5

• 1.0

• 2.0

Calculate 'm' of the AM signal if the peak to peak amplitude of the carrier signal is 10V and V_B rms is 2.

• 0.2

• 0.4

• 0.6

• 0.8

A voice signal contains frequencies 750 Hz and 1.5 KHz modulated with a carrier of 15 MHz. Find the bandwidth of the SSB.

• 750 Hz

• 1.5 KHz

• 2.25 KHz

• 15 MHz