| COMMUNICATION SIGNAL AND SYSTEM |
| PAPER NO. 4 |
 |
 |
 |
|
| PUT ON: Dec, 2K1 |
|
EC-202 COMMUNICATION SIGNAL AND SYSTEM (B.Tech 4th Semester,1202) Time : 3 Hours Maximum Marks : 60 NOTE:- This paper consist of Three Sections. Section A is compulsory. Do any Four questions from Section B and any two questions from Section C Section-A Marks : 20 1(a) Define Gausian Noise. (b) Define Noise Temperature. (c) Define Noise equilent Bandwidth. (d) What is Brust Noise ? (e) What is Matched Filter? (f) What is Conditional Probability? (g) Define a Random Process. (h) What is the Utility of Statistical Average? (i) What is Spectral Density? (j) Fourier Transform representation of a periodic signals. Section-B Marks:5 Each 2. Find the frequency spectrum of single pulse of V volts and T seconds wide using Fourier Transform. 3. Prove the sampling theorm for uneven sampling (i.e. sampling time not constant) that original information is still recoverable. 4. A discrete memoryless noisy symmetric channel is to transmit binary data. If p is the probability of error, then find conditional probabilties of error and probability of receiving 0 or 1 correctly. 5. What are various sources of noise in amplifiers? Explain three of them. What is noise temperature? 6. Show that mean square value of output of a linear bandpass filter(time invariant) existed by a stationary process is given by integral overall frequencies of power spectral density of input random process multiplied by squared magnitude of transfer function of the filter. Section-C Marks : 10 Each 7. (a) A signal x(t) = 3 sin 100t is applied to the filter with H(f) = 5 e-π(5t)2. Find G[x(f)], G[y(f)] and y(bar)2x(bar)2 (b) Define noise factor and signal to noise ratio for a random process. How can these be practally measured ? 8.(a) What is an ergodic process> How is it different from stationary process ? Give examples to illustrate. (b) What is matched filter? Derive an expression for probability of error for binary transmission. 9. (a) Find Fourier Transform for x(t) = e-at sin wot u(t). (b) How is impulse response of a system derived ? Discuss the computation of stop response from impulse response. |
| <<PREVIOUS 1 2 3 4 |