A reconfigurable miniaturized planar inverted‐F antenna with integrated BaSrTiO₃ capacitor

Abstract

In this letter, a wide‐tuning range planar inverted‐F antenna (PIFA) of 17 × 10 mm2 dimension printed on a Rogers duroid RT5880 substrate is presented. The printed circuit board (PCB) dimensions are 1 × 60 mm2. First, the antenna is simulated with a localized capacitor and the effect of the capacitor losses on the antenna efficiency is studied. Then, the antenna is simulated with an integrated BaSrTiO3 (BST) tunable capacitor. The obtained results are in very good agreement with those obtained with localized elements. Finally, the BST thin film capacitor is fabricated and mounted on the antenna. The experimental results show a capacitor tunability of 56.7% at a bias voltage of 35 V, leading to an antenna agility of 42.2%.

Low-Temperature Dielectric Response of Strontium Titanate Thin Films Manipulated by Zn Doping

“…Dielectric thin films are widely used in modern technology and engineering with the aim of decreasing the size and weight of electronic or communications devices, although the physical phenomena in films are much more complicated to study and to understand than the behaviour of bulk materials. In particular, ferroelectric-related films with DC electric field dependent dielectric permittivity are used to develop frequency-agile electronic devices such as varactors, microwave filters, resonators, voltage-controlled oscillators, and phase shifters, besides passive components [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. For these applications, in addition to the high tunability of dielectric permittivity, the films should have low loss and reduced permittivity values [15][16][17].…”

“…Since the tunability of a ferroelectric material is maximized near its Curie point, incipient ferroelectrics such as SrTiO 3 (ST) are useful at cryogenic temperatures (T), whereas regular ferroelectrics such as BaTiO 3 are more suitable above room T [2,15]. Solid solutions of these materials are mainly used for near-room-T applications [4,5,[9][10][11][12][13]16,18].…”

Characterization and Performance Analysis of BST-Based Ferroelectric Varactors in the Millimeter-Wave Domain

“…[2]. In particular, ferroelectric materials, which have the capability to modify their dielectric constant under a continuous electric field [3], are of great interest in the development of tunable capacitors, which are the basic elements of many reconfigurable devices such as phase shifters [4,5], filters [6], or reconfigurable antennas [7][8][9][10]. Moreover, ferroelectrics offer better power handling capabilities than semi-conductors, which suffer from nonlinearity, a better response time than micro-electro-mechanical devices (MEMS), and a low power consumption [11].…”