Abstract
•A wideband W-shaped slot-loaded solid U-shaped rectangular patch antenna is presented.•A low-cost 1.6 mm-thick FR4 microwave substrate is used.•Achieved a wide operating band of 1.54 to 2.75 GHz (56.41%) with good gain, and efficiency.•A small group delay of lower than 1.5 ns and a high-fidelity factor above 80% is achieved.•A low SAR value of 0.26 W/kg (for 10g SAR) is achieved over the operating band.•A near field directivity (NFD) >77% is achieved.•Antenna sensitivity in a realistic head model is carried out using an array and found suitable for the malignant tissue detection system.
This paper describes a wideband W-shaped slot-loaded solid U-shaped rectangular patch antenna for a microwave-based head imaging application. The proposed antenna comprises a W-shaped slot-loaded solid U-shaped radiating patch and a slotted partial ground. Slots have been used to enhance efficiency, current distribution, gain, and other antenna performances. At its first resonance frequency of 1.6 GHz, the optimized electrical dimension is 0.197λ × 0.298λ × 0.085λ. The antenna is printed on a low-cost 1.6 mm-thick FR4 substrate. The antenna feeds with a 50 Ω transmission line. The assessed findings demonstrated that the stated prototype has a 1.12 GHz (1.40 - 2.52 GHz) bandwidth along with omnidirectional radiation properties. The prototype achieved a maximum gain of 3.5 dBi at 2.44 GHz and provided a maximum radiation efficiency of 95% with stable radiation characteristics. The face-to-face alignment fidelity factor (FF) is also determined to evaluate time-domain responses above 80%. Near field directivity (NFD) is also analyzed with a head model to ensure near field radiation characteristics. The SAR value reaches a < 0.3 W/kg limit over the active bandwidth. Finally, in a CST simulation platform, an array configuration with nine antenna elements is deployed in a circular arrangement around the head phantom to collect the scattered data for tumor object characterization.
A U-shaped patch antenna is proposed for a microwave-based malignant tissue detection system. The designed antenna comprises a W-shaped slot-loaded solid U-shaped rectangular patch and a partial slotted ground and possesses an electrical dimension of 0.197λ × 0.298λ × 0.085λ. The measurement revealed that the fabricated antenna achieved an operating bandwidth of 1.12 GHz (1.40 - 2.52 GHz) with good gain, efficiency, and omnidirectional radiation properties. The designed antenna also realized a more than 80% fidelity factor, a SAR value of less than 0.3 W/kg. Finally, a nine-element array of the designed antenna is used in the malignant tumor detection system, proving its suitability in wideband imaging applications. [Display omitted]