Wireless Communication Methods

Infrared Communications
It is found in remote controls for televisions, DVD players and most other entertainment devices.
The key component of an infrared system is an infrared LED (Light Emitting Diode) to emit the light and a photo-diode in the television or equipment to receive the light.
A digital code within the controller switches the light on and off, this is then picked up as a digital code at the other end. The communication standard is called 'IrDA' short for Infrared Digital Association and it allows wire-less communication between Mouse, keyboard, joysticks, gamepads etc.

Advantages	Disadvantages
Inexpensive compared to other technologies	Only works line-of-sight
Works over a moderate bandwidth 115 kbps	Short range - a few metres
Works well over a short distance	Low bandwidth

Laser Communication Methods

This method uses high power laser beams to transmit light signals.

Uses:

• Campus wide communication
• Emergency data links (disaster relief etc)
• Outdoor events requiring high speed data feeds
• Building - to - Building communication
• Satellite to Satellite communication
• Backup network in case main cabled network fails

Advantages	Disadvantages
Wide bandwidth compared to infrared	Affected by weather
Can be set up quickly (compared to laying cable)	Requires line-of-sight to work

Bluetooth

Bluetooth is a type of short range radio communication and networking protocol combined.

It was developed so devices close to one another could exchange data.

Uses: 

• Hands-free mobile telephone calls
• Short range communication such as a PC and a nearby bluetooth enabled printer
• Transferring files, contact details and calendar appointments between devices
• Connection to measurement devices, medical equipment, GPS receivers, bar code scanners
• Connection to industrial and medical sensors

Wireless Communication

This form of communication makes use of radio waves in order to transmit and receive information.

Uses: 

• Connecting to an organisation's Local Area Network
• Connecting to the Internet through a hotspot
• Smartphones and PDA connecting to the internet
• Wirelessly downloading electronic books into a reader
• Wirelessly streaming music throughout a home
• Wi-Fi enabled printers
• Games consoles to connect to the Internet

Advantages	Disadvantages
No need for physical cables	Slower than cabled networks e.g. 54 Mbps compared to the 1000 Gbps that Gigabit Ethernet offers
The laptop or device can work anywhere within range of a WAP	Requires a Wireless Access Point (WAP) to be present
Can work through walls and on different floors as long as the radio signal is not too weak	Requires encryption to ensure data privacy
Smartphones can roam the Internet through the home network without incurring expensive 3G charges	It can only support a limited number of simultaneous connections so not so good as a company-wide LAN
Sufficient bandwidth for most Internet use although streaming video is more of a challenge_blue	Performance depends on the structure of the building and any obstacles there may be weakening the radio signal
Wi-Fi certified devices are guaranteed to be compatible