Glitch filter for distance measuring interferometry
US6975406B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 2, 2002 |
| Grant date | Dec 13, 2005 |
| Priority date | — |
| Expiry date | Oct 11, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2290/70
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus used to reduce glitches in measurements made by an accumulation of phase changes over a range greater than 2π. Embodiments of the invention feature the use of a glitch filter that receives a phase input indicating a position value. The glitch filter reduces glitches by using a feedback term that has been reduced modulo 2π.The method includes measuring a plurality of values of a measurement signal, determining a current position value based on each of the plurality of measured values, wherein determining includes determining a delta value based on a current measured value and a previous position value, wherein the delta value is reduced modulo 2π to a range of ±π, and determining the current position value based on the determined delta value, and outputting at least one of the determined current position value and a velocity value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.