COMPOSITE DIELECTRIC FILTER DEVICE AND COMMUNICATION APPARATUS INCORPORATING THE SAME

摘要

PURPOSE: Composite dielectric filter device is provided to easily improve the isolation characteristics between mutually adjacent filters. CONSTITUTION: A substantially parallelepiped rectangular dielectric block(1) includes seven inner conductor holes(2a-2g) arranged in parallel extending from one face thereof to a face opposed to the face. On each of the inner surfaces of the holes(2a-2g), an inner conductor is formed. In each of the inner conductor holes(2a-2c) and the inner conductor holes(2e-2g), the inner diameter of the hole on one open-face side is large and the inner diameter of the hole on the other open-face side is small to make the hole as a stepped hole. Near each of the open-faces having the large inner diameters, an inner conductor-free portion is formed. The inner conductor-free portion is used as an open-circuited end of each inner conductor. An outer conductor(4) is formed on the six outer faces of the dielectric block(1). One end of the inner conductor formed on the inner surface of each of the inner conductor holes(2a-2c,2e-2g) is short-circuited to the outer conductor(4) on a short-circuited face.