Wireless Communication

Wireless communication is the transfer of information over a distance without the use of electrical conductors or "wires".The distances involved may be short (a few meters as in television remote control) or very long (thousands or even millions of kilometers for radio communications). When the context is clear the term is often simply shortened to "wireless". Wireless communications is generally a branch of telecommunications.

Wireless communication may be via:

• Radio frequency communication,
• Microwave communication, for example long-range line-of-sight via highly directional antennas, or short-range communication, or
• Infrared (IR) short-range communication, for example from remote controls or via IRDA

Wireless communication spans the spectrum from 9 KHz to 300 GHz.

Applications may involve point-to-point communication, point-to-multipoint communication, broadcasting , cellular networks and other wireless networks.

Common examples of wireless equipment in use today include:

1. Cellular phones and pagers: provide connectivity for portable and mobile applications, both personal and business.
2. Global Positioning System (GPS): allows drivers of cars and trucks, captains of boats and ships, and pilots of aircraft to ascertain their location anywhere on earth.
3. Cordless computer peripherals: the cordless mouse is a common example; keyboards and printers can also be linked to a computer via wireless.
4. Cordless telephone sets: these are limited-range devices, not to be confused with cell phones.
5. Satellite television: allows viewers in almost any location to select from hundreds of channels.

Wireless networking is used to meet a variety of needs. Perhaps the most common use is to connect laptop users who travel from location to location. Another common use is for mobile networks that connect via satellite. A wireless transmission method is a logical choice to network a LAN segment that must frequently change locations.

The uses of wireless technology:

• To span a distance beyond the capabilities of typical cabling,
• To avoid obstacles such as physical structures, EMI, or RFI,
• To provide a backup communications link in case of normal network failure,
• To link portable or temporary workstations,
• To overcome situations where normal cabling is difficult or financially impractical, or
• To remotely connect mobile users or networks.
  

More about Wireless LAN network, Wifi and Bluetooth in the forthcoming posts.