EBG-Backed Head Wearable Antenna Array for Transcranial Radio-Frequency Stimulation Applications

A head wearable antenna array embedded on a multilayer substrate to enable unidirectional radiation pattern, broad bandwidth and compact size for trans cranial radiofrequency stimulation is proposed. The top layer consists of
$4\mathrm{x}4$
radiating patches, an EBG array and feeding network while the bottom layer consists of
$4\mathrm{x}4$
MTM reflectors. The EBG array consists of 9-unit cells arranged near the feeding network to reduce the surface waves while the MTM reflectors compel the antenna to radiate towards the broadside thus achieving a unidirectional radiation pattern for the complete structure. A broad impedance bandwidth and compact size are achieved by using the DNG properties of the meta material. The unidirectional pattern along with compact size and broad bandwidth enable the proposed design to be used for transcranial radiof-requency stimulation and other biomedical applications.