Magnetic compensation circuit and method for compensating the output of a magnetic sensor, responding to changes in a first magnetic field
US9389281B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 2013 |
| Grant date | Jul 12, 2016 |
| Priority date | — |
| Expiry date | Oct 6, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/025
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A solution for compensating a magnetic field sensor to permit detection of a small magnetic field in the presence of a large magnetic field is disclosed. A magnetic field sensor detects the magnetic field which produces an analog signal then encoded by an analog to digital converter (ADC) into a digital stream. A controller operating on the digital stream incorporates additional sensor data to create a compensation signal which is sent to a digital to analog (DAC) converter. This compensation signal then modifies the output of the magnetic field sensor before entering the ADC. Compensation is software controlled, and is thus adaptable to numerous conditions requiring compensation. Apart from being easily tunable, the compensation may respond dynamically to changing conditions. The invention has particular application to airborne electromagnetic surveying where small fields scattered from the Earth are measured in the presence of a large transmitted field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.