Comb-line type band-pass filter

Abstract

Abstract PURPOSE:To facilitate easy design and production and at the same time to realize miniturization of overall structure for the titled band-pass filter by using the magnetic field coupling for connection between stages and at the same time distributing resonators in a U-shape. CONSTITUTION:A partition wall 2 made of a conductor is provided to a case 1 which is served in common as an external conductor of a resonator, and a dielectric 3 is filled into the housing 1. Plural hole gaps 41-4n are distributed in a U-shape to the dielectric 3, and internal conductors 51-5n which form a resonator are provided to the inner walls of gaps 41-4n respectively. In addition, an external conductor 6 is provided on the outer surface of the dielectric 3 excluding its open surface. Then input/output coupling elements 90 and 9n+1 are set opposite to conductors 51 and 5n of the first and last stages respectively. In such a way, the magnetic field coupling is applied for connection between stages. Thus eliminates a change of the inter-stage coupling coefficient which is due to a change of dielectric constant even with use of a dielectric resonator. Thus, the design and production of a BPF are facilitated. Furthermore the overall structure of the BPF can be miniaturized owing to a U-shaped distribution of resonators.

Inventors

• 👤 Hiroshi Hatanaka
• 👤 博 畠中

Bibliographic Details