Reference measurement
As a reference measurement in which is metrology and Geodesy determining systematic errors of a method called the parent by measurement on an instrument accuracy occurs, or by localization at a precisely known point.
Reference measurements are often required:
- When calibrating or calibrating measuring instruments, in particular
- in electrical engineering , where measuring devices are subject to a wide range of influences (temperature, etc.)
- for the Global Positioning System (GPS), see also DGPS
- for astro - geodetic measurement methods - see personal equation and instrumental equation