Method and apparatus for reducing microwave oscillator output noise
US5036299A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 1990 |
| Grant date | Jul 30, 1991 |
| Priority date | — |
| Expiry date | Jun 22, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B2202/076
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Microwave oscilltors incorporate r.f. feedback with carrier suppression to reduce phase noise. In a direct feedback oscillator arrngement a circulator is interposed between the r.f. amplifier and the high-Q resonator. The amplifier output is applied to the slightly over-coupled input port of the resonator so that the resultant net return signal is the vectorial difference between the signals emitted and reflected from the resonator. The gain of the r.f. amplifier is chosen to regenerate the forward signal from the net return signal. In a STALO-type arrangement, the resonator is critically coupled and an r.f. amplifier added to the path of the net return signal. The sensitivity of the STALO-type feedback loop is thereby enhanced while added amplifier noise is minimized by the superposition of the signals emitted by and reflected from the resonator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.