Wi-Fi operates in the unlicensed radio frequency bands, specifically the 2.4 GHz and 5 GHz bands. These bands are divided into multiple channels, and devices communicate with each other by transmitting and receiving radio signals within these channels.
Modulation:
Wi-Fi signals use a technique called modulation to encode data onto radio waves. The most common modulation schemes are Quadrature Amplitude Modulation (QAM), which varies the amplitude of the signal, and Phase Shift Keying (PSK), which varies the phase.
802.11 Standards:
The IEEE 802.11 family of standards defines the specifications for implementing Wi-Fi. Different versions of the standard, such as 802.11b, 802.11g, 802.11n, 802.11ac, and 802.11ax, specify various aspects of Wi-Fi, including data rates, frequency bands, and channel widths.
Access Points (APs) and Stations:
In a Wi-Fi network, there are two main types of devices: access points (APs) and stations. An access point acts as a central hub that connects wireless devices to a wired network, typically via a router. Stations are the devices, like smartphones, laptops, and tablets, that connect to the access point.
SSID (Service Set Identifier):
Wi-Fi networks are identified by a name called the SSID. When you want to connect to a Wi-Fi network, you select the network by its SSID. Networks with the same SSID can form an Extended Service Set (ESS), allowing devices to roam seamlessly between access points.
Authentication and Encryption:
Wi-Fi networks use security mechanisms like WPA (Wi-Fi Protected Access) and WPA2/WPA3 to authenticate devices and encrypt data. This ensures that unauthorized users cannot access the network and that data transmitted over the network is secure.
Channels and Interference:
Wi-Fi channels are like lanes on a highway, and devices communicate within these channels. However, neighboring Wi-Fi networks, electronic devices, and other sources of interference can impact the quality of the signal. Selecting the right channel and optimizing channel width can help minimize interference.
MIMO (Multiple Input, Multiple Output):
Many modern Wi-Fi standards support MIMO technology, which uses multiple antennas for both the transmitter and receiver. MIMO improves data throughput and signal reliability by transmitting multiple data streams simultaneously.
Beamforming:
Beamforming is a technology that focuses the Wi-Fi signal in the direction of the connected device, improving signal strength and reliability. It is especially beneficial in environments with multiple devices and potential interference.
802.11ax (Wi-Fi 6):
The latest standard, 802.11ax (Wi-Fi 6), introduces improvements in efficiency, capacity, and performance. It employs technologies like Orthogonal Frequency Division Multiple Access (OFDMA) and Target Wake Time (TWT) to enhance the overall Wi-Fi experience.
