The Friis Transmission Equation

The Friis Transmission Equation describes how well a radio signal travels from a transmitter to a receiver in free space. It predicts the received power based on the transmitted power, the distance between the antennas, and their sizes (or gains). Essentially, it shows that as distance increases, the signal weakens (reduces in power), and larger, more focused antennas can improve reception. This equation helps engineers design communication systems by understanding how signals diminish over space and how to optimize hardware for clearer, stronger wireless connections.