Which of the following is a continuous signal that varies smoothly over time?

• Digital signal
• Analog signal
• Pulse signal
• Baseband signal

What does the Nyquist theorem state regarding a noiseless channel?

• The channel bandwidth must be infinite for error-free transmission
• The data rate is twice the bandwidth
• The signal-to-noise ratio determines capacity
• Data rate equals bandwidth

In unipolar encoding, which of the following represents binary 1?

• Zero voltage
• Positive voltage
• Alternating voltage
• Negative voltage

Which line encoding scheme uses a transition at the beginning of each bit period for synchronization?

• NRZ
• Manchester
• AMI
• Bipolar NRZ

Amplitude Modulation (AM) varies which aspect of the carrier signal?

• Frequency
• Amplitude
• Phase
• Period

Which modulation scheme shifts the phase of the carrier signal?

• AM
• FM
• PM
• ASK

Which of the following is a guided medium?

• Air
• Vacuum
• Twisted-pair cable
• Microwave

Which cable type offers the highest bandwidth and is immune to electromagnetic interference?

• Coaxial
• Twisted pair
• Fiber optic
• Shielded twisted pair

Which of the following multiplexing techniques divides the channel by time?

• FDM
• TDM
• WDM
• CDMA

In Frequency Division Multiplexing (FDM), what ensures that signals do not overlap?

• Filters
• Switches
• Modulators
• Amplifiers