Broad band frequency synthesizer for quick frequency retuning
US5140284A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 1991 |
| Grant date | Aug 18, 1992 |
| Priority date | — |
| Expiry date | Feb 20, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/183
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In a frequency synthesizer of the type having a phase locked loop, a variable frequency divider is coupled to the output of the phase locked loop and a variable divider for dividing a reference signal is coupled to a frequency source for the frequency synthesizer. The phase lock loop also includes a variable divider for dividing the signal fed back from a voltage controlled oscillator to a phase detector. The division numbers or divisors of the variable frequency dividers are controlled such that a predetermined relationship exists among the frequency dividers. The frequency synthesizer is capable of switching reference frequencies without causing phase jumps. The reference frequency is selected depending upon the choice of a division number for the frequency divider coupled to the output of the frequency synthesizer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.