Influence on the ear-to-ear link loss from heterogeneous head phantom variations

We have investigated the detuning of the antennas and the ear-to-ear link loss for the in-the-ear (ITE) binaural hearing aids considering the different heterogeneous human phantoms through FDTD simulations. It was found that the resonance frequency shifts differently for different phantoms and between the ears within the same phantom. The ear-to-ear link loss between the antennas for the homogeneous SAM phantom has been compared with a heterogeneous phantom and was found to be 30 dB lower, indicating the presence of a lossless shell and the absence of a pinna in the SAM phantom underestimate the link loss as compared with a realistic phantom.