Microwave band gap structures (MBG) utilizing fixed defects have received much interest because of their ability to operate as narrow band filters. With the recent interest in reconfigurable wireless devices, the need for electronically controllable narrow band filters is on the rise. By altering the defects in an MBG crystal, the transmission properties of the crystal can be changed. Using this concept, two controllable defect structures have been studied. Microwave band gap crystals utilizing single and dual p-i-n diode defect structures have been simulated, fabricated, and tested. Through the control of the p-i-n diode bias current, the transmission effects caused by the crystal defects can be altered. Experiments demonstrating contrasts of more than 30 dB between the diode-on and diode-off states are presented along with the corresponding finite difference time domain simulation results.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)