1. DATA COMMUNICATION
Lecture-11

2. Recap of Lecture 10 The OSI Model Functions of OSI Layers
TCP/IP Protocol Suite

3. Overview of Lecture 11 Signals Analog and Digital
Analog and Digital Data & Signals
Periodic & Aperiodic Signals

4. Signals
Generally, the information is not in a form that can be transmitted over a Link
The binary digits must be converted into a form that Transmission Medium can accept
The data stream of 1s and 0s must be turned into Signals

5. Analog ANALOG CONTINUOUS
Refers to something that is Continuous
CONTINUOUS
A set of specific points of data and all possible points between them

6. Digital DIGITAL DISCRETE
Refers to something that is Discrete
DISCRETE
A set of specific points of data with no points in between

7. Analog and Digital Data
Analog Data
Human Voice
Digital Data
Data stored in the memory of a computer

8. Analog and Digital Signals

9. Periodic and Aperiodic Signals
(Analog or Digital)
Aperiodic

10. Periodic Signals
A signal is called Periodic if it completes a pattern within a measurable time frame called a Period and then repeats that pattern over identical subsequent Periods

11. Periodic Signal Example

12. Aperiodic Signals
An Aperiodic or Non-Periodic signal is the one that changes constantly without exhibiting a pattern or cycle that repeats over time

13. Aperiodic Signals

14. Analog Signals Analog signals can be classified into:
Simple Analog Signal (Sine wave)
Composite Analog Signal

15. Simple Analog Signal (Sine Wave)

16. Simple Analog Signal (Sine Wave)
Sine waves can be fully described:
Amplitude
Period / Frequency
Phase

17. Amplitude

18. Period and Frequency
T= 1 / f OR f=1 / T

19. Units of Period & Frequency
Seconds____Hertz
Milliseconds____Kilohertz
Microseconds____Megahertz
Nanoseconds____Gigahertz
Picoseconds____Terahertz

20. Summary Signals Analog and Digital Analog and Digital Data & Signals
Periodic & Aperiodic Signals
Sine Waves and its Characteristics

21. Suggested Reading
Section 4.1, 4.2, 4.3 “Data Communications and Networking” 2nd Edition by Behrouz A. Forouzan

22. DATA COMMUNICATION
Lecture-11