Loop system capable of auto-calibrating oscillating frequency range and related method
US7486146B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 27, 2007 |
| Grant date | Feb 3, 2009 |
| Priority date | — |
| Expiry date | Oct 7, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S331/02
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A loop system capable of auto-calibrating an oscillating frequency range includes a frequency error detector, a voltage controlled oscillator (VCO), a voltage input unit, and a switch. The frequency error detector includes a rotational frequency detector, a state machine, and an up-down counter. The rotational frequency detector is used for comparing the reference frequency and the feedback frequency. The state machine is used for determining an auto-calibration state. The up-down counter is used for generating the second control signal or the coarse-lock-state signal. The VCO is used for selecting to operate at one of a plurality of frequency operating curves so as to generate an oscillating signal. The voltage input unit is used for providing a fixed voltage to the VCO. The switch is used for switching the VCO to couple to the voltage input unit or to couple to a fine frequency tuner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.