Low phase noise agile up converter
US5038404A · kind A · utility
43Cited by
5References
16Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 1, 1989 |
| Grant date | Aug 6, 1991 |
| Priority date | — |
| Expiry date | Sep 1, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/16
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The converter has two mixer stages each including a phase locked loop with an oscillator controlled by a phase comparator. The frequency reference to both stages is provided by a single master reference. The frequency of the oscillator in the first stage is offset to accommodate the three different broadcast frequency conventions. A high frequency reference permits the second stage to compensate for noise kilohertz away from the carrier. A local oscillator output which is also phase locked to the master reference is provided for an external video modulator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.