Digitally Reconfigurable Metasurface Array for a Multipath Based Wireless Link With Media-Based Modulation

Electromagnetic (EM) windows with a digitally reconfigurable metasurface (DRM) are proposed to experimentally demonstrate a multipath based communication technique known as media-based modulation (MBM). In MBM, the magnitude and phase of a transmitted tone from a single RF chain are modulated in space using different switching combinations of DRM. After transmission, superposition of various multipath components helps diversifying the transmitted symbols across the constellation leading to an improved signal-to-noise ratio (SNR), bandwidth, and energy-efficient multiuser system with enhanced security, reduced outage probability in a slow fade channel, and possibility of achieving capacity of a Gaussian channel. Prototype of an $8\times $ 8 array of the DRM unit cells with p-i-n diodes for switching and its hardware interface are developed to perform experiments under different scattering environments. Constellations, bit-error-rate (BER) responses, and statistical distributions of the received symbols with the measured data establish the above characteristic features of a wireless link using MBM. A scheme for the data transmission with DRM is also discussed.