Scalp-Implantable Antenna Systems for Intracranial Pressure Monitoring

Abstract

This communication proposes miniaturized implantable antenna systems for biomedical applications, specifically for scalp implantation. The proposed designs exhibit dual-band characteristics on the industrial, scientific, and medical bands (i.e., 915 and 2450 MHz) with small volumes: 344 mm(3) (System A) and 406 mm(3) (System B). Each system is integrated with the microelectronic components and a battery. The key feature of the proposed implantable antenna is its small volume (8 x 6 x 0.5 = 24 mm(3)) with a slotless and a vialess ground plane, thereby reducing design complexity. Moreover, the structure exhibits satisfactory peak gain values of -28.5 and -22.8 dBi at a lower and higher resonant band, respectively. Simulations using the finite-element method and finite-difference time domain are performed to evaluate the implantable systems. For validation, measurements are carried out in a saline solution. The antenna offers a good agreement between the measured and simulation results. In addition, a link budget is calculated to analyze the data transmission range.