Wideband unidirectional antenna for head imaging system

Antennas with wideband performance, compact size and directional radiation are required in microwave imaging and monitoring systems for medical applications. An antenna with a low profile structure along the direction of radiation and 50Ω port impedance are two other requirements in head imaging. To address these issues, a wideband low-profile compact antenna is proposed in this paper. The antenna mainly consists of two printed slabs of substrates that are separated by a properly designed cavity. The printed slabs are connected by two copper walls. The design flow of the antenna is described briefly with a description of various parameters. The antenna covers 48% fractional bandwidth with a stable gain, good radiation efficiency and well directional radiation characteristics.