Bihar engineering university ECE Question paper. Digital communication question paper solution. BEU previous year question electrical and electronic branch. Digital communication solution 2022.
a) Describe the non-coherent detection of M-ary FSK signal.
(b) What are the differences between analog and digital modulation techniques?
(c) Draw block diagram of non-coherent detection of quaternary FSK signal.
(d) Draw equivalent representation of PSK in terms of two ASK systems.
(e) What is signal space?
(f) What are baseband signalling and pass- band signalling?
(g). Differentiate between wide sense stationary and strict sense stationary random processes.
(h) How is source coding different from channel coding?
((i) Discuss BPSK modulator.
(j) What is the difference between DPCM and DM?
BEU PYQ SOLUTION pdf is provided below
2(a) Discuss differential pulse code modulation (DPCM) with the help of neat sketches of modulation and demodulation.
3 (a) Explain the basic principle of M-ary PSK signalling and M-ary PSK signalling for data transmission over bandpass channel. Determine the probability of error of a QPSK receiver in the presence of a channel noise. Mention the advantages of QPSK signalling and MSK signalling.
(b) Explain the importance of companding technique.
- (a) Explain the role of equalizer in communication system.
(b) Binary data is to be transmitted over a microwave channel at a rate of 30 bits/sec. Assuming the channel noise to be white Gaussian with a PSD n/2-10-14 watt/Hz. Find the power and bandwidth requirements 4-phase PSK and 16-tone FSK signalling schemes to maintain an error probability of 10. of
- (a) Compare the average power requirements of binary non-coherent ASK, coherent PSK, DPSK and non-coherent FSK signalling schemes operating at a data rate of 1000 bits/sec over a bandpass channel having bandwidth of 3000 Hz, a n/2-10-10 watt/Hz and P-10-5.
(b)Write the advantages and disadvantages of digital communication system.
6. (a) How are FSK modulation and demodulation done? Explain using block diagrams of modulation and demodulation.
(b) A high frequency transmitter used in a binary communication system is peak power limited to 1 kW. The power loss in the channel is 60 dB and the noise power at the receiver input (nr) is 10 watt. Assuming maximum signalling rate and equiprobable message bits, find P, for non-coherent ASK and coherent PSK signalling schemes.
7. (a) A matched filter has the frequency responseHU- 1-e-120/7Determine the impulse response h(t) corresponding to Hif)
(ii) Determine the signal waveform to which the filter characteristic is matched.
b) Explain Inter Symbol Interference (ISI). Discuss its causes and techniques to reduce it.
8. (a) Draw spectrum and calculate transmission bandwidth of a standard BPSK signal. Consider bit period equal to 0-1 msec and a carrier frequency of 100 kHz. Carrier is sinusoidal.
(b) Two quadrature carriers cos2x/, and sin 2nft are used to transmit digital information through an AWGN channel at two different data rates, 10 kbps and 100 kbps. Determine the relative amplitudes of the signals for the two carriers so that /No for the two channels is identical.
9. Write short notes on the following: 7 2
(a) Delta modulation
(b) Fading and its reduction in wireless digital communication.
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BEU Digital Communication2022 PYQ SOLUTION => Download
BEU Digital Communication 2022 question paper ==> Download