Switchable frequency bands microstrip antennas

Novel microstrip antennas with reconfigurable resonant frequency capability are proposed. The antennas consist of two radiating rectangular patches, connected by thin metallic strip incorporating a PIN diode in between. By controlling the PIN diode bias voltage, the antenna can be switched between two different frequencies. Both simulation and experimental results indicate that without any additional matching elements, the proposed antennas demonstrates very good input match at all the resonant frequencies.