A MEMS-based electrostatically tunable circular microstrip patch antenna

Abstract

This paper reports a MEMS-based electrostatically tunable circular microstrip patch antenna. This antenna is fabricated using printed circuit processing techniques. The microstrip patch antenna is patterned on the top side of a Kapton polyimide film which is suspended above the ground plane. The resonant frequency of the antenna is tuned electrostatically by applying a dc bias voltage between the patch and the ground plane. The movable patch deflects downward toward the fixed ground plane due to electrostatic force of attraction caused by the applied dc bias voltage. This deflection decreases the air gap thereby increasing the effective permittivity of the antenna. This increase in effective permittivity results in a downward shift in the resonant frequency. The patch is inductively coupled to a coplanar waveguide (CPW) feed line via a slot in the ground plane. A 6 mm diameter circular patch antenna tunable from 16.91 GHz at 0 V to 16.64 GHz at 165 V, a tuning range of 270 MHz, is presented in this paper.

Planar patch antenna with 100‐μm slit for size reduction and dual‐band applications

“…Several techniques for size reduction of patch antenna have been previously reported including: use of high permittivity substrate, modifying the shape of the patch, and use of shorting posts . In addition, there has been considerable interest in the development of tunable antennas because of increasing number of global wireless standards . A tunable antenna provides an alternative to a broadband antenna in which an antenna with a small band width is tuned over a frequency range.…”

A MEMS-based tunable coplanar patch antenna fabricated using PCB processing techniques

“…The operating frequency of the antenna was altered by varying the DC bias applied to the varactor diode(s). With the advent of MEMS technology, there have been considerable research efforts in the development of frequency tunable and reconfigurable (or switchable) antennas using RF MEMS devices [8][9][10][11][12][13][14][15][16][17][18]. In [10], a patch antenna operating at 25 GHz was made tunable over a range of 1.6%, i.e., 400 MHz.…”

“…Recently, Printed Circuit Board (PCB) process compatible MEMS-based frequency tunable and reconfigurable antennas have been reported in [17,18]. The advantages of PCB compatible MEMS technology include low cost, compatibility with organic laminate substrates, ease of integration with surface mount components, suitability for batch fabrication in large panels and high volume manufacturing [19].…”

A microelectromechanical accelerometer fabricated using printed circuit processing techniques

“…Recently, PCB MEMS devices such as microfludic components and systems [5][6][7][8], flow sensors [9], tactile sensors [9], pressure sensors [10], conductivity cell and resistive temperature devices [11], RF MEMS switches [4] and tunable antennas [12] have been demonstrated by various research groups.…”