Nanocomposite marvels: Miniaturized high bandwidth microstrip patch antenna for X-band applications

Abstract

Zinc aluminate (ZnAl2O4) is widely recognized as a ceramic in high demand across various microwave applications. Furthermore, blending dielectric materials with ZnAl2O4 has demonstrated improvements in its dielectric properties, offering promising potential for advancing microstrip patch antenna technology. This paper presents the fabrication and characterization of a sol-gel composite nanoparticle consisting of titanium dioxide (TiO2) and zinc aluminate (ZnAl2O4) for use in a microstrip patch antenna designed for X-band applications. The composite nanoparticle, with a molecular composition of xTiO2(1-x)ZnAl2O4 where x = 8 %, was investigated using X-ray diffraction (XRD), revealing dominant peaks corresponding to ZnAl2O4 and TiO2 with a calculated crystallite size of 16.9 nm. Fourier transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FESEM), and energy dispersive spectroscopy (EDS) were employed to assess functional groups, morphology, and elemental composition of the nanoparticles. The dielectric properties of the nanoparticles, characterized by a dielectric permittivity of 20.2 and a dielectric loss of 0.19, were measured using an LCR meter. These nanoparticles were utilized to fabricate a prototype patch antenna, exhibiting promising performance in both simulated and measured results. The fabricated patch antenna operated at 8.51/8.49 GHz with a return loss (RL) of − 25.94/−19.97 dB, featuring an enhanced bandwidth of 2.62/2.87 GHz and a voltage standing wave ratio (VSWR) below 2. Additionally, the antenna demonstrated a gain of 2.14, directivity of 3.58, and radiation efficiency of 59.7 %, making it suitable for X-band applications.