Friis' Formula: Antenna Gain and Power Density

This lecture covers the Friis' formula, which calculates the power density radiated by an isotropic source and a real antenna. It explains how to determine the received power at different distances and the relationship between antenna gain and effective aperture. The lecture also delves into Radio Detection and Ranging (RADAR), discussing equivalent RADAR surfaces, resonances, and different regions. It explores Pulse RADAR, Chirp RADAR, and Doppler RADAR, detailing frequency sweeps, mixers, amplifiers, filters, and loudspeakers. Practical examples are provided, such as calculating frequency shifts in cell phones based on vehicle velocity.