Measurement and visualization of radio waves incident on thin metamaterial absorber

A thin metamaterial absorber is used as a sensor array to measure the 2-d power and phase distributions of radio waves incident on the surface of the absorber. Lumped resistors inserted between the surface patches on a mushroom-type metasurface are used to absorb the incident wave at the resonance frequency. As the voltage induced on each resistor is proportional to the electric field component along it, the amplitude (power) and phase distributions of the incident wave are obtained and visualized as 2-d images by monitoring the individual voltages on the 2-d array of resistors.