Design of wideband slotted Vivaldi antenna for lung tumour monitoring

The presented work reports the design and investigation of a small-sized, wideband (WB), slotted semicircular Vivaldi antenna for lung tumour detection and sensing. To achieve a wideband response, the concept of the travelling waves of a spiral antenna is utilized, and hence, the semicircular slots are introduced on the edges opposite to the curvature of the Vivaldi antenna. The application and significance of the proposed WB antenna as a sensor for the diagnosis of tumours inside the lung tissue have been investigated. During simulation, the voxel model is used to simulate tumours of different sizes. For each size variation, we have achieved a distinguished reflection coefficient response. The antenna measurement is carried out by placing it over the lungs of the human body. The developed antenna provides 108% S11 bandwidth with various resonant frequencies, which are 1.05, 1.48, 1.98, 2.5, and 2.91 GHz, with a maximum gain of 5 dBi.