Spatially light modulated reconfigurable photoconductive antenna

摘要

A reconfigurable photoconducting antenna is created on a semiconductor substrate. At equilibrium, the semiconductor is semi-insulating, and therefore appears as a dielectric. Illuminating a region of the substrate results in the generation of free carriers in the substrate and allows the creation of a conductive region (semi-metallic) in the substrate. This conductive region functions as the radiating element of the antenna. Controlling the pattern of the illuminated region directly controls the pattern of the radiating antenna. By using a digital micromirror device (DMD(TM)) to control the pattern of the light, a desired antenna design may be placed on the semiconductor substrate. The pattern can be dynamically adjusted simply by changing the position of the individual mirrors in the DMD(TM) array. The device operates through a standardized digital interface and can be switched between patterns in a period of approximately 20 microseconds. The pattern of the DMD(TM) can therefore be readily and easily controlled through the use of a digital control system.