Chapter 25: Wi-Fi (IEEE 802.11)

Learning Objectives

• Describe the IEEE 802.11 OFDM physical layer across generations (a/g/n/ac/ax/be), including subcarrier spacing, FFT sizes, guard intervals, MCS tables, and channel bonding mechanisms
• Analyse the CSMA/CA MAC protocol including DCF, EDCA, RTS/CTS handshake, and the hidden/exposed node problems with their mitigation strategies
• Derive the saturation throughput of 802.11 DCF using the Bianchi Markov chain model and identify the key parameters affecting performance
• Explain 802.11ax (Wi-Fi 6) innovations including OFDMA resource unit allocation, uplink MU-MIMO, target wake time (TWT), BSS coloring, and 1024-QAM
• Describe 802.11be (Wi-Fi 7) features including 4096-QAM, 320 MHz channels, multi-link operation, and their throughput implications
• Compare Wi-Fi generations quantitatively in terms of peak throughput, spectral efficiency, latency, and dense deployment performance