Communication Course/Printable version

Communication Course

The current, editable version of this book is available in Wikibooks, the open-content textbooks collection, at
https://en.wikibooks.org/wiki/Communication_Course

Permission is granted to copy, distribute, and/or modify this document under the terms of the Creative Commons Attribution-ShareAlike 3.0 License.

Information

Information is a communication term used to describe any of the following entities

• Audible Sound in the frequency range of 2kHz - 20 kHz . Example human animal sound
• Audible Voice in the frequency range of 3kHz - 30 MHz . Example human speech conversation
• Video in the frequency range of 30Hz - 30 GHz . Example Tivi motion picture
• Data in the frequency range of 2kHz - 20 kHz . Example Computer data

Information Processing

Information exists in many wave forms generate from different sources. Before information can be processed by electronic devices information needs to be converted to electronic waves forming a signal. Then signals can be processed by electronic devices to amplify the signal, with the volume controlled by adjusting the amplitude of the signal.

Signal

Electronic Signal

Information exists in many wave forms generated from different sources. Before information can be processed by electronic devices information needs to be converted to electronic wave forms called signals. Then signals can be processed by electronic devices to amplifying the signal, with volume controlled by adjusting the amplitude of the signal.

Types of electronic signals

• Sine wave
• Square wave
• Triangular wave

Signal Processing

Modulation

Sound, voice

Types of Modulation

• Amplitude Modulation (AM)
• Frequency Modulation (FM)
• Phase Modulation (PM)

Transmitting Medium

Wires

Communication signals travel through wire as radiated electromagnetic wave to receiver

Air

Communication signals travel through the air as radiated electromagnetic wave to receiver

Communication Devices

Communication Devices

• Microphone
• Speaker
• Antenna
• Phone
• Radio
• Cassette
• Disc Player

In computer technology field, communication devices may mean such things as sound cards, internet cards, modems and some other examples of computer interfaces.