This lecture covers Orthogonal Frequency Division Multiplexing (OFDM), a key technology used in high throughput mobile networks like 4G, 5G, and WiFi. It explains how OFDM simplifies channel estimation, the use of multiple sub-carrier frequencies, and the implementation of cyclic prefixes for preserving orthogonality. The lecture also delves into CFO estimation and correction, channel estimation using preambles, and the significance of guard bands in OFDM systems.