Longitudinally coupled double mode surface wave resonators
US5835990A · kind A · utility
38Cited by
13References
41Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1996 |
| Grant date | Nov 10, 1998 |
| Priority date | — |
| Expiry date | Jun 6, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/6463
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A longitudinally coupled double mode surface wave resonator comprises two reflectors, two lateral IDTs (inter-digital transducers), and a centre IDT arranged on a surface of a piezoelectric substrate, for coupling surface waves longitudinally between the IDTs. The two lateral IDTs operate with opposite signal phases by virtue of opposite connections, opposite polarities, or oppositely phased spacings from the centre IDT. Alternatively, or in addition, the centre IDT is divided into two oppositely phased halves. A filter comprising one or more resonators can replace both a filter and a balun in a radio frequency circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.