1. PRIYADARSHNI

2. •Held By
Priya
Darshni

3. 1.FIBER OPTICS
2. SATELLITE N/W
2. SATELLITE N/W
4.LOGICS BEHIND .
LaTST(BTOOTH AND INFRA).

8. Multiplication of two sine waves with different
k
8

9. g ( t )  01100010
 0 ,0  t  1

1,1  t  3


g ( t )   0 ,3  t  6
 1, 6  t  7

 0 ,7  t  8

8
an 
2
T


1
4
 3 sin(  nt / 4 ) dt  7 sin(  nt / 4 ) dt 
6
 1




1
4
[  4 /(  n ) cos(  nt / 4 ) |t 1   4 /(  n ) cos(  nt / 4 ) |t  6 ]
g ( t ) sin( 2 nft ) dt
0
3
7
  4 /(  n )[cos( 3 n / 4 )  cos(  n / 4 )  cos( 7  n / 4 )  cos( 6 n / 4 )]
9

10. a n  1 /(  n )[cos(  n / 4 )  cos( 3 n / 4 )  cos( 6 n / 4 )  cos( 7  n / 4 )]
bn 

2

T
8
1
3
0
4

1
7
[  cos 9 nt / 4 ) dt 

[ sin(  nt / 4 ) |
4
n
1
4

g ( t ) cos( 2 nft ) dt
1
n
4
n
3
t 1

cos(  n / 4 ) dt ]
6
sin(  nt / 4 ) | ]
7
t6
[sin( 3 n / 4 )  sin(  n / 4 )  sin( 7  n / 4 )  sin( 6 n / 4 )]
10

11. c 
2
T

8
g ( t ) dt
0
2  3

1 dt 

1
8 

1
4
 3 

7
6
1 dt 


3
4
Note: The maximum value of sin(x) and cos(x) is
1 and the minimum value is -1. The maximum
and minimum values of cos(x1) - cos(x2) + cos(x3) cos(x4) and sin(x1) - sin(x2) + sin(x3) - sin(x4) are 4
and -4, respectively. Hence,an and bn converge to
zero when n becomes infinite.
11

12. A binary signal and its rms Fourier amplitudes.
amplitude
1
0 1 1 0 0
0 1 0
0.5
0.25
0
1 2
3
4
5
6
7
8
9 10 11 12 13 14 15
Successive approximations to the original signal
1
1 harmonic
0
1
Time
Harmonic number
12

13. Successive approximations to the original signal
1
2 harmonies
0
1
2
1
4 harmonies
0
1
2
3
4
1
8 harmonies
0
1
Time
2
3
4 5 6
7
8
Harmonic number
13

14. Typical circuit route for a medium-distance
call.
14

15. A Two-antenna
satellite (a)
15

16. • The PSTN (Public Switched Telephone Network) is the world's
collection of interconnected voice-oriented public telephone
networks. It's also referred to as the POTS (Plain Old Telephone
Service).
(a) Fully-interconnected network.
(b) Centralized switch.
(c) Two-level hierarchy.
16

17. (a) Circuit switching (b) Message switching (c) Packet switching
17

18. (a) Circuit switching.
(b) Packet switching.
18

19. 

Defines the Interface Between the Host (DTE)
and the Carrier's Equipment (DCE)
X.25 Has 3 Layers:




Physical (X.21 and X.21 bis)
Frame
Packet
Will Look at Digital Interface (X.21). 15 pins
19

20. 
RS-232C

RS-449/442-A/423-
A

X.21 (15 pins)
20

21. Signal lines used in X.21
T (Transport)
C (Control)
R (Receive)
I (Indication
DTE
DCE
S (Signal, i.e. bit timing)
B (Byte timing) optional
Ga (DTE common return)
G (Ground)
21