Wireless Networks: How Do They Work?

February 22, 2010

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.

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). 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.” 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.

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. Because of industry compliance with these standards, wireless networking is both easy to use and affordable today.