Investigations of Capacitance Change In Antenna Design for Smart Stent Development

After stents, which are widely used in the treatment of artery blockages, are implanted, the condition of the artery is generally monitored only through additional angiography. In this study, capacitance changes in antenna design were investigated with the aim of developing a smart stent to monitor the artery's condition externally. Considering frequency ranges where electromagnetic waves have deeper penetration into human tissue, various antennas were designed for this application, and the effects of capacitance changes in the 30 MHz to 500 MHz range on the antenna's return loss and inter-antenna coupling were observed. The results of this study demonstrate that frequency shifts caused by the increase in capacitance of a MEMS-based capacitor on thesmart stent, due to increased pressure in a narrowing artery, can be detected. Simulation results showed that as capacitance increases, there is a progressive shift in the antennas' resonance frequencies.