Investigation of dielectric activities on ceramic material with frequency variation in microwave application for antenna
摘要
In this research, the influence of sintering behavior on the electronic and electrical properties of alumina–silica ceramic porcelain compositions was investigated over a broad frequency range from 20 Hz to 20 GHz. Additionally, simulation studies of the proposed cylindrical dielectric resonator antenna (CDRA) were conducted using ANSYS High Frequency Structure Simulator (HFSS) to evaluate its suitability for wideband microwave applications. Different samples were prepared using varying concentrations of Alumina (Al2O3) from 45 to 25 wt% by replacing with Silica (SiO2) content from 0 to 20 wt% in the base composition. The green ceramic powders were shaped into pellets using a uniaxial pressing method under a pressure of 160 MPa, followed by sintering at 1350 °C with a heating rate of 5 °C/min and a soaking time of 2 h. The dielectric properties and loss characteristics of the sintered samples were systematically examined as the functions of both frequency and temperature. The X3 composition, containing 10 wt% silica and 35 wt% alumina, sintered at 1350 °C, exhibited a dielectric constant of 5.75 with a low dielectric loss of 0.03 within the 2–20 GHz frequency range at room temperature. Under temperature variations from 30 to 190 °C, the same composition demonstrated dielectric constant values ranging from 5.4 to 5.8 and dielectric loss values between 0.03 and 0.10 at 6 GHz. The antenna simulation study is conducted using Ansoft’s HFSS software. A fabricated composite material (X3) is used for the DRA design, with the Roger FR4 substrate, which increases the antenna’s bandwidth by 101% through simulation. It provides a sharps resonant frequency of 7.57 GHz within the operating bandwidth (3.2–10.9 GHz), corresponding to a minimum input reflection coefficient of − 44.01 dB. The broadside radiation pattern of the antenna is transformed into a directive radiation pattern with a reduced beam width. The resultant composition X3 provides the best results as a physico-mechanical high-strength material and also provides the better electronic properties as a dielectric value for microwave applications.