197. The bit rate of a digital communication system is 34 M bit/s. The modulation scheme is QPSK. The baud rate of the system is

A. 68 M bit/s

B. 34 M bit/s

C. 17 M bit/s

D. 8.5 M bit/s

198. A TDM link has 20 signal channels and each channel is sampled 8000 times/sec. Each sample is represented by seven binary bits and contains an additional bit for synchronization. The total bit rate for the TDM link is

A. 1180 M bits/sec

B. 1280 K bits/sec

C. 1180 M bits/sec

D. 1280 M bits/sec

199. In a certain '12 channel TDM' system, it is found that channel No. 3 andchannel No. 8 are connected to thesame input signal. This technique

A. wastes thechannel capacity

B. takes care of different sampling rates

C. is required whendifferent bandwidth signals are to be transmitted

D. reduces noise

200. If carrier moudlated by a digital bit stream had one of the possible phases of 0, 90, 180 and 270 degrees, then the modulation is called

A. BPSK

B.QPSK

C. QAM

D.MSK

201. A TDM link has 20 signal channels and each channel issampled 8000 times/sec. Each sample is represented by seven binary bits and contains an additional bit for synchronization. The total bit rate for theTDM link is

A. 1.18 k bits/sec

B. 1.28 k bits/sec

C. 1.128 M bits/sec

D. 1.28 M bits/sec

202. A comparison of frequency division and time division multiplexing systems shows that

A. FDM requires a lower bandwidth, but TDM has greater noise immunity

B. FDM has greater noise immunity and requires lower bandwidth than TDM

C.FDM requires channel synchronisation, while TDM has greater noise immunity

D.FDM requires more multiplexing while TDM requires band pass filter

203. The ramp signal m(t) = at is applied to a delta modulator with sampling period T, step size 8. Slope overload distortion would occur if

A. 8

B.8>a

C. < aT

D. > aT

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