Variable bandwidth filtering and frequency converting system
US4262361A · kind A · utility
39Cited by
6References
8Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 29, 1979 |
| Grant date | Apr 14, 1981 |
| Priority date | — |
| Expiry date | Jun 29, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B21/02
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A system which provides frequency conversion and continuously variable bandwidth control uses fixed filters to which opposite edges of the passband of the signal are applied in inverted frequency relationship. A channel contains the filters and three mixers to which injection signals derived from a single variable frequency oscillator and a fixed oscillator are applied to vary the bandwidth of the system without affecting the center frequency of the signal after processing in the system. The system may be designed to obtain either a variable bandpass or rejection band filtering characteristic.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.