Programmable SAW filter module
US7750752B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 13, 2007 |
| Grant date | Jul 6, 2010 |
| Priority date | — |
| Expiry date | Oct 6, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/6403
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Programmable SAW filter module are provided to overcome undesirable drawbacks, limitations and shortcomings associated with “in-line” SAW filters, such as insertion loss, propagation loss and strong signal capture effects. The programmable SAW filter modules remove the SAW structure from the primary signal path, adding signal gain to drive the splitter and using the SAW portion of the circuit as a programmable impedance element. The programmable SAW filter module includes an amplifier, an impedance, a surface acoustic wave propagation element, a splitter, input and output IDT electrodes, input and output interdigitated transducers, means for gain control and a combiner to combine or sum the signals received from the output IDT electrodes and form an output signal. The input and output IDT's are fully integrated circuits comprising the power splitter and power combiner functions, the phase shift, and gain functions. The embodiments include an amplifier and impedance preceding the input splitter, the amplifier preceding the input splitter with the impedance connected to the combiner, and placing programmable SAW devices in both branches of the circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.