Frequency synthesizer of the phase lock loop type
US4024464A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 1975 |
| Grant date | May 17, 1977 |
| Priority date | — |
| Expiry date | Nov 19, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L2207/04
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A frequency synthesizer of the phase lock loop type including a reference frequency source, a voltage-controlled oscillator and a frequency divider connected to the oscillator output to divide the output frequency by a selectively-variable integer N. The outputs of the frequency divider and the reference frequency source are applied to a phase comparator which has an output connected to a filter. The filter output is applied through a multiplier, having a multiplication factor n proportional to N, to the input of the voltage controlled oscillator. The frequency divider and the multiplier are controlled by the same control means in order to keep the loop gain constant, irrespective of the amount of change in N.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.