High frequency narrow-band multi-mode filter
USRE33957E · kind E · reissue
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1986 |
| Grant date | Jun 9, 1992 |
| Priority date | — |
| Expiry date | Apr 8, 2006 |
Classification
- Technology area (CPC —)General
Abstract
A high frequency narrow-band pass multi-mode filter in constructed in such manner that SAW of SSBW resonators are closely disposed to each other on a single piezoelectric substrate to generate different vibration modes of different resonance frequencies, conditions that the resonators are acoustically coupled to each other to cause these vibration modes, are experimentally found, and the above conditions are satisfied by the filter. In order to reduce the ohmic loss of a very narrow common bus bar, the number of strip pairs of electrode in both interdigital transducers (hereinafter referred to as IDT) is minimized and instead reflectors are provided on the both sides TDTs to compensate for the reduction of its Q value. A part of the bus bar for the IDT electrodes is formed integral with some or all of gratings of the reflectors, whereby the connecting positions of the grating electrodes with respect to lead terminals can be positioned with a high freedom.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.