Design of a compact unidirectional antenna for microwave imaging applications

Abstract

The article reports the design and analysis of a compact three-dimensional microstrip antenna with an operating bandwidth from 1.14 GHz-2.53 GHz. The proposed design achieves a directional radiation pattern with 75.75% of impedance bandwidth. The lower frequency range enables proper signal penetration into the human body. The antenna shows the front-to-back ratio around 2.28 dB-4.2 dB and efficiency more than 87%. The overall dimension of the designed antenna is 0.62 × 0.08 × 0.012 λ3, where λ represents the effective wavelength of the smallest frequency in the required band of operation. This antenna can be used for microwave imaging systems for biomedical applications.