Wi-Fi is a local wireless network technology that helps us connect laptops, PCs and other network ready devices. Wi-Fi generally uses either the 2.4 GHz or the 5 GHz radio band. Every year millions of Wi-Fi devices are sold in the entire world.
Some consider that Wi-Fi was born back in 1985, when the US opened up several wireless frequencies that could be used without purchasing any license. The term Wi-Fi was first used commercially back in August 1999, Interbrand Corporation being the name behind it. However, it seems that Wi-Fi’s roots go back to 1970, when the University of Hawaii created the very first wireless network, allowing the people living on the Hawaiian Islands to communicate much faster.
In 1991 the Institute of Electrical and Electronics Engineers started to standardize the various WLAN technologies, and 6 years later the first standard appeared – the 802.11 technology. This standard would have been too slow for most of our usage scenarios, but the good news is that the devices using this standard are no longer manufactured or used.
Eight years later, the Wi-Fi technology was finally introduced to large audiences, although the speed of the network wasn’t that big. Still, there were very few mobile phones and very few laptops, so there wasn’t a need for higher wireless network speeds. A new standard, the 802.11b was created later on, supporting a bandwidth of up to 11 Mbps, which was similar with the speed of the Ethernet technology at that time. The “b” technology had a lower price and a decent range, so Wi-Fi took off.
Four years later there were many Wi-Fi based mobile devices, and they were being used for both personal and business reasons. The 802.11g standard was then approved; the technology delivered up to 54 Mbps, using the 2.4 GHz band. It was much faster and, due to the regulated frequencies, there was a low rate of interference with other devices.
Later on, with the introduction of the first smartphones, a new Wi-Fi standard was launched by the Institute of Electrical and Electronics Engineers – the 802.11n standard. The letter “n” meant faster speeds, along with a dual frequency transmission: 2.4 GHz and 5 GHz. The technology uses multiple wireless signals and antennas, and this is called the MIMO (multiple input, multiple output) technology.
The advantages of 802.11n were faster speed, better signals, less interference. It is true that the routers were more expensive, and since the signal was stronger, there was a risk of interfering with other similar devices in the area. According to Data Alliance Wireless Network Gear, the modern Wi-Fi networks that utilize the 802.11 ac standard can provide a maximum data transfer rate of up to 1.4 Gbps. These days you can easily turn your car into a Wi-Fi hotspot by purchasing an inexpensive dongle, or by simply utilizing your smartphone’s Internet tethering option.
There were some problems as people began to use Wi-Fi more and more. The 2.4 GHz frequency is also being used by home devices like microwave ovens, cell phones, etc, so the 5 GHz frequency was the much sought after solution.
Today, you can buy inexpensive routers that work simultaneously on both frequencies. The 5GHz band is used when a device is in close range; when it is not, the 2.4 GHz signal is used instead. This means that the device can always benefit by having access to the most powerful Wi-Fi signal.
The 2.4GHz band is 100MHz wide, so it can reach 2.5 GHz. It’s a frequency that is also used by microwaves, cordless phones, baby monitors and wireless video cameras, as well as by the Bluetooth communications. The 2,4 GHz band is divided by IEEE into 14 distinct channels. The width of these channels depends on the technology that’s being used by the 802.11 transmitter. Most of these channels have an overlapping frequency space; however, there are three of them which are completely distinct.
The 5GHz band provides more channels, and for this reason there is less interference in this band. More than this, two channels can be joined, leading to the creation of a wider frequency band. And the newest 802.11 ac technology has even made it possible to link even more channels.
Wi-Fi technologies are used to provide Internet access in private homes, business buildings or public spaces, by making use of Wi-Fi hotspots. Wi-Fi is also being used to provide city-wide Internet access.
Several cities around the world have full Internet access, by making use of hotspots. More than that, many universities have decided to provide campus-wide Internet access. Wi-Fi is also being used to connect two computes or more, without the need of an access point. The technology is known as ” Wi-Fi transmission”.