A Novel Efficient Wirelessly Powered Biotelemetric Endovascular Aortic Stent Antenna System

Abstract

For the treatment of abdominal aortic aneurysm (AAA), this article presents a wirelessly powered stent antenna system for endovascular aneurysm repair (EVAR) comprising an in-body biotelemetric stent receiver (Rx) and off-body wireless power transmitter (Tx), operating at the industrial, scientific, and medical (ISM) bands (868, 915, and 2450 MHz). The Rx stent is composed of a single metallic wire in a serpentine-shaped helix aiding in the mechanical stretchability and random distribution of currents on the stent-struts. The simulated properties of the EVAR stent system were validated through measurements performed on a 3-D printed AAA model placed in a minced pork and a saline-filled ASTM phantom. The wireless power-reception capability and better antenna characteristics of the proposed stent system, such as omnidirectional radiation pattern, high gain, and perfect impedance matching, are among its key benefits in addition to EVAR application. The EVAR stent offers multiband coverage (720–1190 MHz, 2050–2560 MHz) and peak gains of -12.1, -11.7, and -22.4 dBi at the respective ISM bands, with a wireless power transmission efficiency up to 4% at 10 cm and 1.6% at 15 cm Tx–Rx separation. The rectifier exhibited a peak efficiency of 85% at an input power of 15 dBm. A link budget analysis demonstrated the stent’s biotelemetric capabilities. The proposed EVAR stent exhibited a good agreement between the simulation and measured results, thereby serving as a first validation of wirelessly powered EVAR stent antenna.