Resonator, filter, communication device and manufacturing method of resonator

The invention provides a resonator, a filter, a communication device and a manufacturing method of the resonator. Specifically, the resonator comprises a dielectric cover plate, a dielectric cylinder and a cavity, and the cavity is provided with an upper end opening. Wherein the cavity comprises a bottom and a side wall, the dielectric cylinder is arranged on the bottom, a blind hole formed in the outer surface of the cavity is formed below the bottom, the position of the blind hole corresponds to the position of the dielectric cylinder, and the height of the dielectric cylinder is not larger than that of the side wall. And then, the dielectric cover plate is arranged on the upper end opening of the cavity to seal the upper end opening so as to form a whole resonator, and the outer surface of the whole resonator is provided with a metallization layer. Experiments prove that compared with the prior art, the Q value is higher under the condition of the same volume of the resonator, and the increase amplitude of