Dielectric loaded Yagi fed dual band pyramidal horn antenna for breast hyperthermia treatment

This paper introduces the detailed design and experimental demonstration of a narrow beamwidth and low side lobe level pyramidal horn antenna based on placing a ten directors Yagi array as an exciter instead of simple monopole antenna. Teflon rectangular parallelepiped is used as a dielectric material where Yagi array is placed for horn feeding purpose. Directors' length, position, separation, and their number are chosen carefully to obtain a high gain, suitable 3 dB beamwidth, and suitable side lobe level as compared to conventional one. The proposed pyramidal horn antenna achieves a simulated gain, 3 dB beamwidth, and side lobe level of 13.8 dBi, 37.4 degrees, and -26.3 dB at 4.86 GHz, respectively. The proposed antenna is mainly designed for breast cancer hyperthermia therapy where narrow beamwidth, low side lobe level, and high gain are essentially requisites. For verification purpose, the proposed antenna irradiate a breast phantom for 10 minutes and with 2 watt at its input port. The breast phantom temperature is elevated 4 degrees above normal temperature. These results candidates the proposed antenna for breast cancer hyperthermia treatment.