Frequency generator compensated as a function of at least one physical parameter of the environment
US4015208A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 8, 1975 |
| Grant date | Mar 29, 1977 |
| Priority date | — |
| Expiry date | Sep 8, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04G3/022
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A frequency generator comprises a quartz crystal controlled oscillator subjected to at least one variable physical parameter such as temperature and has an arrangement for calibrating the frequency with respect to a standard signal with simultaneous compensation for variations of the physical parameter(s). This arrangement comprises a first set of selectable memories storing values to control the division ratio in a dividing chain. These memories are inscribed in a learning period for a few values of the physical parameter(s); simultaneously, digital values supplied by at least one probe, each value corresponding to a range of values of the parameter, are stored in a second set of memories associated with the probe(s). During operation of the generator, a comparator compares the actual digital value supplied by the probe(s) with the values stored in the second set of memories, to select the corresponding memory of the first set for controlling the division ratio, at least one probe sensitive to a physical parameter of the environment, and means associated with each said probe to form selection signals each selection signal representing various possible values of the parameter consi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.