Wireless Networks: How Do They Work?

by: Ron King

Wireless networks use radio waves instead of wires to transmit data between computers. Here's how: The Binary Code: 1s and 0s It's well known that computers transmit information digitally, using binary code: ones and zeros. This translates well to radio waves, since those 1s and 0s can be represented by different kinds of beeps. These beeps are so fast that they're outside the hearing range of humans. Morse Code: Dots And Dashes It works like Morse code, which is a way to transmit the alphabet over radio waves using dots (short beeps) and dashes (long beeps). Morse code was used manually for years via telegraph to get information from 1 place to another very quickly. More importantly for this example, though, it is a binary system, just as a computer system is. Wireless networking, then, can be thought of as a Morse code for computers. You plug in a combined radio receiver and transmitter, and the computer is able to send out its equivalent of dots and dashes (bits, in computer-speak) to get your data from here to there. Wavelengths And Frequencies You might wonder how the computer can send and receive data at high speed without becoming garbled nonsense. The key to wireless networking is how it gets around this problem. First, wireless transmissions are sent at very high frequencies, which allows more data to be sent per second. Most wireless connections use a frequency of 2.4 gigahertz (2.4 billion cycles per second) -- a frequency similar to mobile phones and microwave ovens. However, this high frequency produces a wavelength that is very short, which is why wireless networking is effective only over short distances. Wireless networks also use a technique called "frequency hopping." They use dozens of frequencies, and constantly switch among them. This makes wireless networks more immune to interference from other radio signals than if they transmitted on a single frequency. Internet Access Points The final step for a wireless network is to provide internet access for every computer on the network. This is done by a special piece of wireless equipment called an access point. An access point is more expensive than a wireless card for 1 computer, because it contains radios capable of communicating with around 100 computers, sharing internet access among them. Dedicated access points are necessary only for larger networks. With only a few computers, it is possible to use 1 of them as the access point, or to use a wireless router. Industry Standards Wireless equipment from different manufacturers can work together to handle these complex communications because there are standards which guide the production of all wireless devices. These standards are technically called the 802.11. Because of industry compliance with these standards, wireless networking is both easy to use and affordable today. Wireless Is Simple To Use If all this talk of frequencies has you worried -- relax. Wireless networking hardware and software handle all of this automatically, without need for user intervention. Wireless networking, for all its complicated ability, is far simpler to use than you might expect. About the author: Ron King is a full-time researcher, writer, and web developer. Visit http://www.havewireless.comfor more info. Copyright 2005 Ron King. This article may be reprinted if the resource box is left intact. Circulated by Bandoni Media