Thermal Imaging for Power Density Measurement of Microwave Fields

This book concentrates on Lock-in infrared (IR) thermography for finding power distribution of electromagnetic waves on plane surfaces. The electromagnetic radiations emanating from a microwave source are made to fall on a thin absorption screen. These waves are amplitude modulated. The waves falling on the screen result in temperature rise of the screen. Thermal images of the screen are taken by an IR camera at some fixed frame rate and hence a thermal movie is recorded. Amplitude images of the thermal movie determine the power pattern of these waves at the screen location. Power distribution of various patch antennas over plane surfaces was determined using this technique.