Digital compass having a ratiometric bearing processor
US4412387A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 10, 1982 |
| Grant date | Nov 1, 1983 |
| Priority date | — |
| Expiry date | May 10, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C17/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A digital compass including a two-axis earth's magnetic field sensor and a earing processor computes the bearing for local display or transmission from a remote site to a local site for display and/or storage. The bearing processor portion of the digital compass includes an analog-to-digital converter configured for ratiometric measurements to compute the ratio of the x-axis and y-axis signals (smaller divided by the larger) from the aforementioned two-axis earth's magnetic field sensor. A programmable memory unit controlled, inter alia, by the data line outputs of the analog-to-digital converter, contains the arc tangent function for angles from 0.degree. to 90.degree.. The data line outputs from the memory unit defines a quadrant displacement angle in the range of 0.degree. to 90.degree. which is subsequently added to the cardinal point forming the lower boundary in bearing of the host quadrant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.