Compensated ensemble crystal oscillator for use in a well borehole system
US8340911B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 10, 2006 |
| Grant date | Dec 25, 2012 |
| Priority date | — |
| Expiry date | Jul 25, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04F5/06
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A compensated ensemble crystal oscillator clock system. The clock system includes preferably four quad compensated clocks, a compensated temperature sensor, and software for processing and correcting system response. Physical fabrication of elements of the quad compensated clocks, the compensated temperature sensor and cooperating software minimized drift in frequency of the oscillator clock system in harsh borehole environments encountered while drilling a borehole. The clock system exhibits a frequency stability of 2.8×10−9 or less over a temperature range of from 0° C. to 185° C. The compensated ensemble crystal oscillator clock system is particularly applicable to seismic-while-drilling operations wherein precise downhole measurements of time are required typically over a period of days.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.