Microstrip Patch Antenna Populates CPW Stub With MEMS Capacitors

Using radio-frequency microelectromechanical-systems (MEMS) technology, a tunable frequency microstrip patch antenna has been developed. It consists of a patch antenna loaded with a coplanar-waveguide (CPW) loading section, which is attached to the antenna via a microstrip-to-CW transition. To provide reconfigurability in the antenna's resonant frequency, MEMS bridges act as a variable capacitor placed on the CPW stub. The MEMS capacitors are electrostatically actuated with a low tuning voltage in the range of 0 to 11.9 V. As the actuation voltage is increased over that range, the antenna resonant frequency can be continuously shifted from 16.05 GHz down to 15.75 GHz. This patch antenna was developed by Emre Erdil, Kagan Topalli, Mehmet Unlu, Ozlem Aydin Civi, and Tayfun Akin with support from the Middle East Technical University's Microelectronics Facilities. See "Frequency Tunable Microstrip Patch Antenna Using RF MEMS Technology," IEEE Transactions on Antennas and Propagation, April 2007, p. 1193.