WiFi is a widely recognised wireless networking technology, allows electronic devices to connect to a local area network primarily through the 2.4 GHz and 5 GHz radio bands. It is based on the IEEE 802.11 family of standards and is used for providing internet access and network connectivity for a variety of devices including computers, smartphones, tablets, smart devices, and more.
The fundamental principle of WiFi involves the use of one or more wireless access points, which acts as the central transmitter and receiver of wireless signals. Devices equipped with WiFi capabilities can connect to the router to access the internet and exchange data with other connected devices. The technology uses radio waves to transmit information across a network, employing a method known as spread-spectrum transmission, which enhances the security and reliability of the data transmitted.
One of the key characteristics of WiFi is its range, which varies depending on the environment and the specific standard used. Typically, WiFi networks cover an area of up to several hundred meters, with the range being influenced by factors such as physical obstructions, signal interference, and the power of the wireless router. The latest 802.11ax standard can reach as far as 400 metres in clear outdoor areas.
WiFi Standards
When WiFi devices are referred to by 802.11g, 802.11n, 802.11ax, etc., they are referred to by their Standard, which can be thought of like a 'generation' or an 'evolution'. The IEEE (Institute of Electrical and Electronics Engineers) develops these standards to ensure interoperability and compatibility among different WiFi devices. Each standard specifies particular technical parameters, including frequency bands, data rates, and modulation techniques.
Name | Alias | Bands | Spatial Streams | Max. Modulation |
---|---|---|---|---|
802.11b | Wi-Fi 1 | 2.4 GHz | 1x1 SISO | DSSS |
802.11a | Wi-Fi 2 | 5 GHz | 1x1 SISO | 64QAM |
802.11g | Wi-Fi 3 | 2.4 GHz | 1x1 SISO | 64QAM |
802.11n | Wi-Fi 4 | 2.4 GHz, 5 GHz | 4x4 MIMO | 64QAM |
802.11ac Wave 1 | Wi-Fi 5 | 5 GHz | 3x3 MIMO | 256QAM |
802.11ac Wave 2 | Wi-Fi 5 | 5 GHz | 4x4 MIMO | 256QAM |
802.11ax WiFi-6 | Wi-Fi 6 | 2.4 GHz, 5 GHz | 8x8 MIMO | 1024QAM |
802.11ax WiFi-6E | Wi-Fi 6E | 2.4 GHz, 5 GHz, 6 GHz | 8x8 MIMO | 1024QAM |
802.11ah | HaLow | 900 MHz | 4x4 MIMO | 256QAM |
802.11ay | WiGig | 61 GHz, 60-80 GHz | 8x8 MIMO | 64QAM |