Title:
LADDER-TYPE CERAMIC FILTER
Document Type and Number:
Japanese Patent JP2001285022
Kind Code:
A
Abstract:
To provide at a low price a ladder type ceramic filter which suppresses spurious signal by using a small number of kinds of resonators.
The subordinate resonance frequencies of resonators S1 to S4 which are arranged at serial branches are made different in position from one another by varying the depths of slits formed in the center parts of four sides of the resonators. Thus, the high-order subordinate resonance frequencies are dispersed, so that spurious signals can be suppressed.
Inventors:
MIZUNO ETSUKO
Application Number:
JP2000094160A
Publication Date:
October 12, 2001
Filing Date:
March 30, 2000
Export Citation:
Assignee:
NGK SPARK PLUG CO
International Classes:
H03H9/58; H03H9/17; (IPC1-7): H03H9/58; H03H9/17
Attorney, Agent or Firm:
Matsuura Kitao
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