Dual-band Microstrip Patch Antenna for Fully-Wireless Smart Stent

Cardiovascular diseases (CVDs) remain the dominant cause of mortality globally and are of an increasing trend. Generally, coronary stent placement is a pervasive treatment to combat CVDs. However, the cardiovascular stent employed as the passive expanded support in the blocked artery frequently introduce a postoperative complication called in-stent restenosis. The innovative self-reported stents integrated with biosensors can offer effective diagnosis and treatment of in-stent restenosis. In addition, the use of biotelemetry is essential in the interaction with physiological signals in the vessel's lumen, ensuring continuous monitoring of internal conditions within a vessel. This paper presents two compact dual-band microstrip antennas with encapsulation and without encapsulation that can implement power and data transmission. In particular, the 1.4 GHz Wireless Medical Telemetry Service (WMTS) band and 2.45 GHz Industrial Scientific and Medical (ISM) band have been allocated for wireless power transfer and biotelemetry, respectively. The proposed stent antennas employ meander slots on the radiating patch, which can achieve an ultra-small volume of 5 × 5 × 0.64 mm3. Moreover, the antenna configurations, reflection coefficient values, and surface current distribution plots are compared between the encapsulated and unencapsulated antennas.