Electronic compass
US5924212A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 6, 1997 |
| Grant date | Jul 20, 1999 |
| Priority date | — |
| Expiry date | Oct 6, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An electronic compass includes at least two coil assemblies. Each coil assembly has a magnetic axis which is oriented at a known angle to that of the other coil. Each coil assembly has a pair of substantially identical coils having magnetic axes that are parallel in a reverse sense. The compass further includes an oscillator which oscillates at a frequency which is dependent upon the inductances of the coils. A current source causes current to flow in the coils and a switch alternately couples the current source to each of the coils of the coil assemblies. A processor analyzes the frequencies of oscillation of the oscillator when each of the coil assemblies is coupled to the current source in order to compute geographic orientation based upon the analysis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.