solution for analog communication for analog communication may 2016 index q.1) a) . 2 b) . 2 c) ....
Post on 24-Mar-2018
214 Views
Preview:
TRANSCRIPT
Mumbai University EXTC (Semester -V)
1 |www.brainheaters.in
Solution for Analog Communication
May 2016
Index
Q.1)
a) …………………………………………………………………………. 2
b) …………………………………………………………………………. 2
c) …………………………………………………………………………. 3-4
d) …………………………………………………………………………. 5
Q.2)
a) …………………………………………………………………………. 6-7
b) …………………………………………………………………………. 8-9
Q.3)
a) …………………………………………………………………………. 10-14
b) …………………………………………………………………………. 15-16
Q.4)
a) …………………………………………………………………………. 17-18
b) …………………………………………………………………………. 19-21
Q.5)
a) …………………………………………………………………………. 22-23
b) …………………………………………………………………………. 24-25
Q.6)
a) …………………………………………………………………………. 25-26
b) …………………………………………………………………………. 26-28
c) …………………………………………………………………………. 28-30
d) …………………………………………………………………………. 31
e) …………………………………………………………………………. 32-33
Mumbai University EXTC (Semester -V)
2 |www.brainheaters.in
Q1) (a) Why IF is selected as 455 KHz in AM? Solution:
(b) Distinguish between narrow band FM and wideband FM. Solution:
Mumbai University EXTC (Semester -V)
3 |www.brainheaters.in
(c) What are the causes of fold over distortion? How it can be prevented?
Solution:
Mumbai University EXTC (Semester -V)
4 |www.brainheaters.in
(d) Explain double spotting with reference to radio receiver. Solution:
Mumbai University EXTC (Semester -V)
5 |www.brainheaters.in
(e) Define noise figure and signal to noise ratio. Solution:
Q2)
Mumbai University EXTC (Semester -V)
6 |www.brainheaters.in
(a) One input to AM modulation is 500 KHz carries with an amplitude of 20 Vp.The second input is 10 KHz modulation signal that is of sufficient amplitude to cause in o/p wave of ± 7.5 Vp .Determine.
(i) Upper and Lower side frequency. (ii) Expression for modulated wave. (iii) Draw o/p spectrum. (iv) Modulation co-efficient and prevent modulation. (v) Total transmitted power.
Solution:
Mumbai University EXTC (Semester -V)
7 |www.brainheaters.in
Mumbai University EXTC (Semester -V)
8 |www.brainheaters.in
(b) Explain practical diode detector with delayed AGC. Solution:
Mumbai University EXTC (Semester -V)
9 |www.brainheaters.in
Q3) (a) Explain indirect method of FM generation.
Solution:
Mumbai University EXTC (Semester -V)
10 |www.brainheaters.in
Mumbai University EXTC (Semester -V)
11 |www.brainheaters.in
Mumbai University EXTC (Semester -V)
12 |www.brainheaters.in
Mumbai University EXTC (Semester -V)
13 |www.brainheaters.in
Part 4: Use of frequency Multipliers Mixer and Amplifier: The FM signal produced at the output of phase modulator has a low carrier frequency and low modulation index. They are increased to an adequately high value with help of frequency multipliers and mixer. The power level is raised to the desired level by the amplifier.
Mumbai University EXTC (Semester -V)
14 |www.brainheaters.in
(b) Explain ratio detector in detail with suitable diagram. Solution:
Mumbai University EXTC (Semester -V)
15 |www.brainheaters.in
Mumbai University EXTC (Semester -V)
16 |www.brainheaters.in
Q4) (a) Explain independent sideband technique in detail.
Mumbai University EXTC (Semester -V)
17 |www.brainheaters.in
(b) Explain Super Heterodyne radio receiver in detail with block diagram. Solution:
Operation :-
Mumbai University EXTC (Semester -V)
18 |www.brainheaters.in
In order to maintain a constant difference between the local oscillator frequency and the incoming frequency, ganged tuning is used .This is simultaneous tuning of RF amplifier, mixer and local oscillator and it is achieved by using ganged tuning capacitors
Mumbai University EXTC (Semester -V)
19 |www.brainheaters.in
Q5)
Mumbai University EXTC (Semester -V)
20 |www.brainheaters.in
(a) Explain block diagram of adaptive delta modulator with waveform. Solution:
As shown in Fig due to variable step size, the slope overload error is
reduced. But quantization error is increased. Due to the adjustable step size, the slope overload problem is solved. Hence ADM system has a low bit rate than the PCM system. Therefore the BW required is also less than a comparable PCM system.
Mumbai University EXTC (Semester -V)
21 |www.brainheaters.in
Mumbai University EXTC (Semester -V)
22 |www.brainheaters.in
(b) State and prove sampling theorem for pass band signal. Solution:
Mumbai University EXTC (Semester -V)
23 |www.brainheaters.in
Q6)Write short note on any four of the following. (a) PLL FM demodulator. Solution:
Mumbai University EXTC (Semester -V)
24 |www.brainheaters.in
(b) Quadrature Amplitude Modulation. Solution:
Mumbai University EXTC (Semester -V)
25 |www.brainheaters.in
Mumbai University EXTC (Semester -V)
26 |www.brainheaters.in
(c) TDM and FDM. Solution:
Mumbai University EXTC (Semester -V)
27 |www.brainheaters.in
TDM :-
Mumbai University EXTC (Semester -V)
28 |www.brainheaters.in
(d) Companding Solution:
Mumbai University EXTC (Semester -V)
29 |www.brainheaters.in
(e) Aliasing error and aperture effect.
Solution:
Mumbai University EXTC (Semester -V)
30 |www.brainheaters.in
top related