distance root mean square (GPS) (drms)

For a better determination of the position accuracy of navigation satellites, the root mean square value, the Distance Root Mean Square (drms), is formed. It is the root mean square value of the deviation of the distance between the correct values and the value determined over several measurements. In the GPS system, two drms values are usually used, which lie in a circle marked with certain deviations and represent 95% of all measured values.