Frequency tunable microstrip patch antenna using RF MEMS technology


Erdıl E., Topallı K., Unlu M., Cıvı O. A., Akin T.

IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, vol.55, pp.1193-1196, 2007 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 55
  • Publication Date: 2007
  • Doi Number: 10.1109/tap.2007.893426
  • Journal Name: IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1193-1196
  • Keywords: microelectromechanical system (MEMS), microstrip antennas, microwave, reconfigurable architectures
  • Middle East Technical University Affiliated: Yes

Abstract

A novel reconfigurable microstrip patch antenna is presented that is monolithically integrated with RF microelectromechanical systems (MEMS) capacitors for tuning the resonant frequency. Reconfigurability of the operating frequency of the microstrip patch antenna is achieved by loading it with a coplanar waveguide (CPW) stub on which variable MEMS capacitors are placed periodically. MEMS capacitors are implemented with surface micromachining technology, where a 1-mu m thick aluminum structural layer is placed on a glass substrate with a capacitive gap of 1.5 mu m MEMS capacitors are electrostatically actuated with a low tuning voltage in the range of 0-11.9 V. The antenna resonant frequency can continuously be shifted from 16.05 GHz down to 15.75 GHz as the actuation voltage is increased from 0 to 11.9 V. These measurement results are in good agreement with the simulation results obtained with Ansoft HFSS. The radiation pattern is not affected from the bias voltage. This is the first monolithic frequency tunable microstrip patch antenna where a CPW stub loaded with MEMS capacitors is used as a variable load operating at low do voltages.