Multimode Filters.
Abstract
This report describes work on Multi Mode Filters performed from 1 June 1976 to 28 February 1977. The objective of this program is to develop design criteria and establish tradeoffs for the transduction of acoustic bulk waves in crystal stacks, for use in filtering applications. A primary goal of the program is to explore methods of obtaining miniature low-loss acoustic filters using interactions among the three modes in each crystal layer, which depend on the thickness coordinate. This report is concerned with Phase I of this overall Multi Mode Stacked Crystal Filter Program: The detailed requirements of this phase were to consider: (1) Number of crystal plates in the stack. Emphasis is placed on two- and three-plate stacks, exclusive of bonding or coupling layers, relative thicknesses of the plates, and bonds of coupling layers. (2) Materials comprising each crystal plate, bond, or coupling layer. Emphasis is placed on quartz and highly piezoelectric materials, such as lithium niobate. The material parameters used in all of the stacked filter programs are arbitrary; however, most results are illustrated using the material parameters of AT-cut quartz or are illustrated using the material parameters of AT-cut quartz or multiples of them. Results for berlinite are included (Section 2). (3) Number of thickness modes coupled piezoelectrically, in a given plate, to the electrode system. Number of thickness modes, coupled mechanically at the interfaces, for achieving the filter response. Emphasis is placed on one- and two-shear or quasi-shear modes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1977
- Accession Number
- ADA046091
Entities
People
- A. L. Kachelmyer
- C. M. Stearns
- S. W. Tehon
- S. Wanuga
Organizations
- General Electric