Optically controlled millimeter wave antenna

We have developed an optically-controlled, millimeter wave (MMW) scanning antenna. A computer controlled light source photo-injects a spatially varying plasma into a photoconducting wafer. The light-modified wafer forms MMW beams from 20 to 100 GHz and scans them /spl plusmn/30/spl deg/ in two-dimensions. Beam scan rates are greater than 1000 beams per second with excellent beam control in software. Scanning antennas based on this approach promise to be fast, inexpensive, and easily controlled.