Abstract: Aiming at the problem of microwave heating uniformity, we designed a new curved slot waveguide heating structure based on the theory of slot array antenna. The results show that the design improves the electric field uniformity inside the heating cavity through random superposition of the electric fields radiated by multiple slots. The curved surface structure design makes it easier to conformally align with the cylindrical heating cavity, while reducing the volume of the entire microwave heater. After heating the rubber with a thickness of 5 mm for 20 s, the temperature difference coefficient （COV） reaches 0.56, which is 60% higher than the traditional box type microwave heating device with the same power density, and the uniformity is better improved.

Key words: curved waveguide, slot array, Taylor distribution, microwave heating