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What is the main advantage of Biphase encoding?

• Requires less bandwidth than NRZ encoding

• Has significant DC components

• Can be synchronized

• Suitable for long-distance applications

In Manchester encoding, how is the bit '0' typically represented?

• Transition from low to high in the middle of the bit

• Constant high signal throughout the bit

• Transition from high to low in the middle of the bit

• No changes at all

What is the purpose of the mid-bit transition in Differential Manchester encoding?

• To transmit data

• To reduce bandwidth requirements

• For timing purposes only

• To reduce noise interference

Which scrambling technique replaces a string of eight zeros with a code violation to improve long-distance signaling?

• HDB3

• AMI

• B8ZS

• Manchester

What is a common application of Amplitude-Shift Keying (ASK)?

• High-frequency radio signal transmission

• Token ring LANs

• Fiber optic systems (Intensity Modulation)

• Long-distance twisted pair cables

Which digital modulation technique is often described as 'insensitive to degradation from noise' because the information is sent in its phase?

• ASK

• FSK

• PSK

• QAM

In M-FSK, how does the required bandwidth change when the value of M (the number of frequencies) increases?

• decreases

• remains constant

• increases

• is zero

What is the purpose of Gray coding in QPSK (4-PSK)?

• To increase the total energy of the signal

• To reduce the number of phases required

• To reduce bit errors when symbol errors occur

• To simplify the timing mechanism

Consider a situation where NRZ (Non-Return-to-Zero) encoding requires a Baud rate of 10 ksymbols/second. If Biphase encoding is used for the same data rate, what will be the maximum Baud rate required for the Biphase signal?

• 5 ksymbols/second

• 10 ksymbols/second

• 20 ksymbols/second

• 40 ksymbols/second

An engineer is designing a wireless communication system where the size of the antenna must be at least 1/10 of the wavelength. If the system operates at a frequency of 300 MHz, what is the minimum required size of the antenna (in meters)? (The speed of light in a vacuum c = 3×10^8 m/s)

• 0.01 meters

• 0.1 meters

• 1 meter

• 10 meters