Infrared and radio transmission

Comparison between Infrared and Radio Communications

1. Infrared & Radio Transmission

2. Infrared Transmission Infrared (IR) light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light E mployed in short-range communication among computer peripherals and personal digital assistants and electronic devices

3. Uses infrared light-emitting diodes Receiver uses a silicon photodiode to convert the infrared radiation to an electric current Responds only to the rapidly pulsing signal created by the transmitter, and filters out slowly changing infrared radiation from ambient light Propagation

4. Uses Short Range Communication Indoor use

5. Advantages Simple Circuit Cheap Low Power Consumption No Licenses Needed Higher Security Simple Shielding Portable

6. Disadvantages Works ONLY on Line-of-Sight (LOS) Mode Short Range Blocked by common materials: people, walls, etc Low bandwidth Speed is comparatively slow

7. Examples Remote Control Mobile Phones

8. Radio Transmission Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light

9. Propagation Radio waves travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space Information is carried by systematically changing (modulating) some property of the radiated waves, such as amplitude , frequency , phase , or pulse width

10. Uses Audio Telephony Video Navigation Radar Data (Digital Radio) Radio control

11. Advantages Simple Circuit Cheap No Licenses Needed High Speed/Bandwidth Covers Large Areas (Penetrates through walls)

12. Disadvantages Limited number of free frequency bands Shielding is difficult Interference with other electrical devices Greater Power Consumption Limited Spectrum of Frequency

13. Examples FM Channels Walkie Talkies