Tunable Photogenerated Silicon Plasma Monopole Antenna

An experimental investigation into the frequency tuning of a photogenerated silicon plasma monopole antenna is presented. A high resistivity silicon chiplet is mounted on a patterned PCB substrate in which a photoconductive region within the chiplet functions as the radiator element of a monopole antenna. By turning on a sequentially increasing number of optical fibers located underneath the chiplet, the total length of the monopole is increased, tuning its center frequency. The experimental results demonstrate tuning from 50.0 to 21.1 GHz, for a tuning ratio of 2.37 : 1, with good agreement between simulation and measurement. This work demonstrates the exciting potential to make widely tunable antenna elements for reconfigurable plasma antenna array systems.