Quadrature Phase-shift Keying
A. Converts digital data to analog signal
B. The baud rate is twice the bit rate
C. Allows 64 different combinations
D. The phase shifted is 180 degree
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Compare with UTP and COAX
A. UTP is more expensive
B. UTP is more prone to noises
COAX requires more boosts
D. COAX is eayier to install
Compare Optical fibers with copper wires
A. Optical fibers are heavier than copper wires
B. Copper wires can provide higher bandwidth
C. Optical fibers suffer from interference
D. Optical fibers are widely used for backbone networks
For Shannon's Theorem:
A. It does not consider noise on the channel
B. It is more accurate more the Nyquist's Therom
C. it uses signal-to-noise ratio
D. It can only be applied on copper wires
If the baud rate is 1200 symbol per second and Quadrature Phase-shift Keying is used for modulation, please calculate the data rate:
A. 300 bps
B. 600 bps
C. 2400 bps
D. 4800 bps
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