Microwave sensor array based on split ring resonators for tumor detection and localization

A microwave sensor array for tumor detection and localization was designed and fabricated on an FR-4 substrate. The sensor consists of three square-shaped split-ring resonators coupled to a microstrip feeding line. Each sensing cell produces a stopband in the transmission spectrum of the device. The sensing cells are mutually decoupled, so that the deposition of the sample on one of the cells induces shift of resonant frequency of only that cell, thereby enabling spatial resolution. The sensing performance was experimentally verified with the samples of animal tissues in an ex vivo setting. Pork fat and lean tissues were used for preparing the samples, since the dielectric contrast between them roughly corresponds to the contrast between healthy and tumorous tissue. Experimental results suggest that the designed sensor can be effectively used for tumor detection and localization.