Microstrip Patch Antenna Linear Arrays for Brain Tumor Detection

An EBG is designed at the ground plane of a pentagon microstrip patch antenna for detecting brain tumors. Two circular EBG types have been introduced. The first type is a rectangular lattice of holes which produced an increase in S₁₁ by 19% at the same resonance frequency which is 3.9 GHz with and without tumor. The second one is a squared lattice of holes that presented an increase of 27 % in S₁₁. It also provides a 2.9% shift in the resonant frequency at -10 dB on a head phantom with a brain tumor compared to without a tumor. The electric field, magnetic field, and current density are calculated in each type of EBG. A remarkable difference has been observed between with and without tumor especially on the squared lattice. One-, two-and four- elements linear antenna arrays are designed to be put at a 10-mm distance from the head phantom. The purpose of antenna arrays is to provide sufficient energy to penetrate human tissues. The directivity was increased as 6.65 dB, 8.5 dB, and 12 dB in one element, two elements, and four elements respectively. The S₁₁ is calculated for each antenna on a head phantom with and without tumor. The S₁₁ values are increased by 1.05dB, 2.73dB, and 4dB for the three cases respectively. Finally, the E and H fields, current density and specific absorption rate SAR are also calculated.