Method for noise reduction in a phase locked loop and a device having noise reduction capabilities
US7880516B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 2005 |
| Grant date | Feb 1, 2011 |
| Priority date | — |
| Expiry date | Apr 12, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/1976
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A method for reducing noise in a device that includes at least one phase locked loop (PLL), the method includes: adjusting at least one adjustable component of a PLL such as to determine a time shift; modulating a frequency divider such as to generate a modulation noise within a modulation noise period and to provide a frequency divided signal; introducing the time shift between the modulation noise period and a measurement period; and measuring during a measurement period a difference between a reference signal and the frequency divided signal. A device that includes a phased locked loop. The phase locked loop (PLL) includes: a frequency divider, adapted to receive an output signal from a controlled oscillator and to provide a divided frequency signal; a modulator, adapted to affect at least one frequency division characteristic and to introduce a modulation noise during a modulation noise period, a phase detector, adapted to measure, during a measurement period, a difference between a reference signal and the frequency divided signal; and an adjustable delay unit adapted to affect an adjustable time shift between the modulation period and the measurement period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.