High-Power RF/Microwave Systems in Medical and Agricultural Applications

Duke, NCSU and UGA are working on a novel approach to replace pesticides targeting plant-parasitic nematodes (PPN) with an effective, safe and eco-friendly soil sterilization. PPN are thermally eradicated (>56°C) by transmitting down 1–2 feet below a directional antenna transmitting penetrating ElectroMagnetic (EM) waves (915MHz). During Phase 1, in planting bed-mimicking lab experiments, we proved that 915MHz EM energy thermally destroys deep-seated infectious PPN J2 in minutes, thus allowing next-day planting. The initial small field trial indicated weed eradication, potentially improved yield and no phytotoxicity. Together with a specifically designed lensing antenna, the groundbreaking approach relies on solid-state amplifier technology to replace fragile, bulky and high voltage magnetrons. While the initial work has been performed with LDMOS technology, next generation sources for this application are based on GaN on SiC in long-pulse high power (several kW per pallet). The same approach can also be used for medical applications, especially thermal therapies (ablation and hyperthermia) and novel imaging approaches (thermoacoustic). We will present several exciting new applications were GaN on SiC can dramatically impact agricultural and medical fields.