Dielectric filter, dielectric duplexer, and communication device

摘要

A low-profile dielectric filter includes a dielectric substrate having an opening that extends from a top to a bottom surface of the substrate. A bottom electrode is bonded to the bottom surface of the dielectric substrate, covering the opening to define a depression. Dielectric resonators are mounted in the depression, the bottom electrode serving as a weight-bearing support surface for the dielectric resonators. A plurality of electric devices, such as a resistor, a diode and an air-core coil, are mounted to the dielectric substrate, and a top electrode is mounted to the top surface of the dielectric substrate. The top electrode connects the dielectric resonators and the electric devices. A cover is placed so as to cover the area in which the resonators are mounted.