VREDNOTENJE PONOVLJIVOSTI OPAZOVANJ RTK GPS Z ANALIZO VARIANCE
EVALUATING THE REPEATABILITY OF RTK GPS MEASUREMENTS USING ANALYSIS OF VARIANCE

Atunç Pirti

DOI: 10.15292/geodetski-vestnik.2012.03.427-442

 

Izvleček:

Namen raziskave je oceniti ponovljivost RTK-metode GPS-opazovanj v odvisnosti od različne geometrije razporeditve satelitov in z uporabo različnih referenčnih postaj. Uporabili smo metodo enosmerne analize variance (ANOVA), ki omogoča učinkovito primerjavo spremenljivosti podobnih meritev. RTK-metodo GPS-opazovanj smo opravili z več referenčnimi postajami, saj je tako mogoče doseči homogeno natančnost v celotni mreži. Prav tako je natančnost manj odvisna od oddaljenosti izmeritvenih točk od referenčne postaje. Tako sta omogočeni visoka zanesljivost in dostopnost opazovanj, saj lahko eno referenčno postajo ob morebitnem izpadu nadomestimo z drugo, kar je velika prednost pred uporabo samo ene referenčne postaje. Z metodo ANOVA lahko učinkovito preverimo kakovost popravkov, ki jih ustvarijo posamezne referenčne postaje.

Ključne besede: RTK GPS, natančnost, ponovljivost, ANOVA

 

Abstract:

The purpose of this study is to evaluate the repeatability of RTK GPS method under varying satellite configurations by using different reference points. Furthermore, we conducted one way Analysis of Variance (ANOVA), which is a powerful tool for comparing the variability of related types of measurements. Multi-reference station is a well–known approach in RTK GPS. Using multi-reference points is an effective way to achieve consistent accuracy in the whole net by making errors less distance dependent on the reference stations. It is possible to achieve high reliability and availability by using multi-reference stations. If one station goes down or starts to provide suspicious values, it is possible to compensate the situation with other stations, while this is not possible when a single reference station fails. Here we present ANOVA which is an effective method to check the quality of corrections generated from each reference station.

Keywords: RTK GPS, Accuracy, Repeatability, ANOVA

 

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