Voltage controlled oscillator with frequency and phase control loop
US4156204A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 3, 1976 |
| Grant date | May 22, 1979 |
| Priority date | — |
| Expiry date | Jun 3, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/0807
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The inventive synchronization circuit accepts a reference input signal and produces a signal which is in both phase and frequency lock therewith. The reference signal is quadrature detected via a voltage controlled oscillator signal, a quadrature phase shifter and a pair of mixers. A frequency error signal is generated by processing the mixer outputs through a phase detector and integrator. A phase error signal is produced by extracting and combining the DC components of the signals at the mixer outputs. The frequency and phase error signals are summed to produce a control signal which is fed back to the voltage controlled oscillator, thus causing the oscillator signal to tend to lock in frequency and phase with the input reference signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.