Design of a wideband Unidirectional Antenna for Microwave Head Imaging System

Head imaging system requires the antenna with low profile structure having directional radiation pattern and lower operating frequency range. The essential features like wide bandwidth, reduced dimension, and unidirectional radiation characterize the microwave imaging (MI) systems for biomedical applications. The article reports the design of a compact microstrip antenna and analysis with an operating frequency from 2.46 GHz-3.30 GHz. The lower frequency range satisfies the requirement of proper signal penetration into the human head. The antenna provides the radiation efficiency more than 84% The proposed design covers 29.16% of fractional bandwidth with considerable radiation characteristics. The dimension of the designed antenna is 0. 58 lambda. x 0.49 lambda x 0.12 lambda, where lambda represents the wavelength of the smallest frequency in the required band of operation. This antenna shows stable gain and good radiation efficiency that can be used for biomedical applications in microwave imaging (MI) systems.