Frequency-Tunable High-Power Mesoband Microwave Radiator

This paper presents a frequency-tunable high-power mesoband microwave radiator that uses a switched quarter-wavelength oscillator and a patch antenna. The oscillator is charged and then switched by an annular electrode between the inner and outer conductors. The length of the oscillator is adjustable by moving the electrode in order to generate different frequency resonances. A coupler with a quasi-constant coupling coefficient was employed to output a high-power mesoband microwave. A novel high-power wideband patch antenna with a bandwidth of 64% and a maximum gain of 8.1 dB was used to radiate the generated mesoband microwave. The experimental results of the radiation factor were as high as 182 kV at 333 MHz, and the measured center frequency of the radiated mesoband microwaves ranged from 227 to 345 MHz.