Optimal gain of implanted huygens source antenna and effect of encapsulation material

Implanted antennas are essential components of implanted medical devices. However, their gain and efficiency are significantly constrained by the lossy nature of biological tissue. Huygens source antennas, which combine fundamental TE and TM modes, are promising candidates for implanted applications, as the TE10 and TM10 modes exhibit relatively low near-field losses. Due to the differing loss characteristics of the TE10 and TM10 modes, the optimal gain and power distribution between these modes in an implanted scenario differ from those in free space. In this paper, we study the theoretical optimal gain of implanted Huygens source and the corresponding optimal power distribution. The theory is examined with ideal source simulation in Altair Feko. Additionally, the emergence of novel materials has further accelerated the development of implanted medical devices. In this context, this paper also provides a detailed study on the impact of encapsulation materials on the optimal gain of implanted Huygens source antennas.