Wi-Fi Technology And
Radio Frequency Bands Explained
Wireless communications in the 802.11 arena has been taking the world by storm over the last decade.
One of the great things about Wi-Fi is that it operates in the unlicensed radio spectrum, and is available for anyone.
We’re going to be learning what is wifi technology by talking about wireless standards, wifi range and the RF wifi channels which it can operate on.
WHNME will teach you how it all works, so you have a great knowledge and understanding when trying to troubleshoot your wireless home network.
Since wireless technology is embedded into wireless devices used in transmitting and receiving radio signals based on 802.11 wireless standards, we’ll need to cover those topics individually so you can follow the path from source to destination.
- How Does WiFi Work
- WiFi Devices
- WiFi Range Extender
- Wireless Signal Booster
- Upgrading Internal WiFi Modules
- Build A Homemade WiFi Antenna
WHNME will teach you all about this free and unlicensed area of the radio spectrum, staring with a brief history of how it began and who sets the guidelines for its use.
The question ” what is wifi ” has only been around since the mid 1980’s when the FCC decided to open several bands of the wireless radio spectrum for public use.
Wireless devices in the 2.4GHz and 5GHz frequency bands can broadcast wireless signals without the need of a government license as long as they use a technology called “spread spectrum” while in operation.
After several years an organization called IEEE which stands for The Institute of Electrical and Electronics Engineers emerged and formed a set of standards for implementing wireless communications known today as the 802.11 wireless family based on a set of protocols.
We’re going cover each wifi technology standard by the date they were released, what frequency ranges they operate in, and the data transfer rates that can be expected when applied to a “real world” application.
802.11 Wireless Standards:
02.11a and 802.11b (Released in September 1999)
These two wifi technology standard protocols were released at the same time, but have two very distinct operating features.
802.11a operates on the 5GHz band mostly on the 5.15GHz – 5.25GHz range for indoor use. There are also 3 more ranges 5.25GHz – 5.35GHz, 5.47GHz – 5.725GHz and 5.725GHz – 5.825GHz, however these ranges have several operating rules for their use that we won’t cover here.
The maximum data transfer rate is stated at 54Mbps, but real world speeds have proven closer to 20Mpbs.
802.11b operates on the 2.4GHz band between the 2.412 GHz – 2.484GHz range, and has realistic network speeds around 11Mpbs.
802.11g (Released in June 2003)
This wifi technology uses the 2.4GHz frequency range of 802.11b while capitalizing on the OFDM transmission method of 802.11a that allows data to be divided into several parallel streams to achieve data rates up to 54Mbps, but averages about 20Mbps in real world.
802.11n (Amended in October 2009)
This protocol as of now is still not finalized by IEEE and is still being updated with new amendments to the original draft, which is why its referred to as the “Draft-N” standard.
However, wireless networking equipment manufactured to its specifications is shipping to consumers all around the world, at this very moment.
802.11n operates on both 2.4GHz and 5GHz frequency bands creating a new wifi technology called “dual band” which gives it greater flexibility, and faster data transfer rates up to 600Mpbs using its multiple-input multiple-output antenna technology referred to as MIMO.
The 802.11b/g – 2.4GHz frequency band ranges from 2.412 to 2.484GHz, and is divided into 14 wifi channels 22MHz wide, and spaced 5MHz apart creating wifi channel overlaps.
In the United States due to an overwhelming usage of electronic devices on the 2.4GHz frequency range, there are only three non-overlapping channels which are usable by U.S. regulations.
For the 2.4GHz band wifi channels 1, 6, and 11 are the best channels to use. Wifi channels 12 and 13 are not allowed in Northern America due to government restrictions.
Try to avoid operating electronics in the 2.4GHz within 3 meters of your wireless router. Devices which may interfere with your wireless signals broadcasting in this range include microwave ovens, baby monitors and cordless phones. Try using a DECT 6.0 cordless phone which operates on the 1.9GHz frequency band.
For the 5GHz band the best wifi channels are 36, 40, 44, and 48 indoors and 149, 153, 157 and 161 for outdoors.
The 802.11a Wireless Router Range with WiFi technology has an approximate indoor wifi range of 115ft, and 390ft outdoors in best weather conditions.
Wireless 802.11b/g wifi technology can travel 125ft indoors and can reach out to 460ft outdoors with a clear line of sight.
The 802.11n wifi technology signals have greater range due the advanced MIMO antenna technology allowing it to penetrate indoors up to 230ft and extend outdoors to a wifi range of 820ft in the best working environment.
|Network Standard||Frequency Range||Bandwidth||MIMO Streams||Indoor Range||Outdoor Range|
For best performance results when using a Dual Band router, try connecting all your high bandwidth intensive equipment for streaming video and music in your entertainment area on the 5GHz band, and have all your computers connecting at distant wifi range to the 2.4GHz band for accessing email and html pages.
The 2.4GHz wifi range travels farther through walls and solid objects because of its bigger wavelength allowing it to connect with wireless enabled devices at greater distances, however it operates on the same frequency as common household electronics causing interference.
The 5GHz signal wifi range is a much shorter, because it has a hard time passing through walls and objects; however this frequency range is not used by many electronic devices making it free from most electronic interference’s.
That’s it! We hope you now have a better understanding of what is wifi and how wifi technology works in your wireless home network environment.