Active polyphase filters
US4723318A · kind A · utility
46Cited by
3References
10Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 16, 1985 |
| Grant date | Feb 2, 1988 |
| Priority date | — |
| Expiry date | Dec 16, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2011/0494
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An active polyphase filter arrangement in which asymmetric poles and zeros are obtained using feedback. In implementing the active polyphase filter arrangement there is provided a feedforward path comprising a first polyphase filter and a feedback path comprising a second polyphase filter. Both filters are preferably two phase filters. In operating the polyphase filter arrangement the loop gain at the unwanted "image" frequency can either be made much greater than unity thereby making the feed forward path insensitive to mismatching or be made much less than unity thereby making the feedback path insensitive to mismatching.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.