Compact Slot Microstrip Patch Antenna Loaded with Open Metal Cavity for Microwave Hyperthermia

Cancer is a significant disease that often results in severe side effects from traditional treatments. Microwave hyperthermia has emerged as a minimally invasive, highly effective, and low-toxicity treatment option that has gained widespread use in recent years. The primary objective of this study is to develop and assess a miniaturized slit patch antenna designed to operate at 2450 MHz for hyperthermia therapy. The octagonal antenna patch features four symmetrical slots to reduce its size, enhance directional radiation, and improve focusing and penetration depth. Additionally, a metal cavity is incorporated at the top of the antenna to create a gap between the antenna and the skin, allowing for skin heat dissipation, improved impedance matching, reduced outgoing radiation, and enhanced directional radiation. The performance of the antenna is assessed based on specific absorption rate (SAR), penetration depth (PD), and effective field size (EFS). Subsequently, the antenna is fabricated and tested in pork tissue, with the measured results demonstrating good agreement with the simulated outcomes.