Monolithic tunable recursive filter
US6121825A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 1998 |
| Grant date | Sep 19, 2000 |
| Priority date | — |
| Expiry date | Jun 5, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H11/04
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In a tunable recursive filter implemented in a microwave monolithic integrated circuit (MMIC), a second-order recursive filter included two first order filters, having first and second transmission lines, respectively, connected in parallel. An amplifying unit having a cascode amplifier is arranged in a forward path shared by the two first-order filters. A combiner receives an input signal and a first and second feedback signals fed back through the first and second transmission lines, respectively, and combines such signals to output a combined signal. The amplifying unit amplifies the combined signal and outputs an amplified signal. A divider divides the amplified signal from the amplifying unit, outputs a first portion of the divided signal, and feeds back a second and third portion of the divided signal through the first and second transmission lines.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.