Design of dual-band implantable antenna for intra-oral tongue drive system

Intra-oral tongue drive system(ITDS) is an assistive technology that can help patients who have lost their ability of independent life. To meet the working requirements of the ITDS and to provide good wireless communication capability, an implantable antenna with dual-band, flexible, broadband and miniaturized characteristics is proposed. Considering the computational time and the feasibility of the design scheme, the antenna is designed in a single-layer human muscle model. Then a multi-layered human oral cavity model is used to verify the performance of the antenna in the ITDS. The compact structure of the antenna is achieved by the curved flow structure and defective ground structure; and with help of the feed point position, the dual-band and broadband characteristics of the antenna are realized. Furthermore, to avoid the direct contact between the antenna and human body and improve the safety, a protective layer is introduced by coating the same material as the dielectric substrate on the upper and lower surfaces of the antenna. After simulation and calculation, the antenna sample is fabricated and measured in the fresh mince pork and simulation fluid. The results show that the antenna can work stabely in 0.433 GHz and 2.45 GHz bands. In addition, the impedance bandwidth reaches 78.2% and 34.2%, the size is only 10 mm×10 mm×0.35 mm, while the antenna exhibits a low specific absorption rate value. The remote field data transmission capability is tested and the results indicate that the antenna has good far-field transmission capability, which can meet the application requirements of the ITDS.