Simulation of polygon area determination using GPS single frequency code receivers – Case study

Abstract

Spatial data play a significant role in the carrying out many scientific studies and statistical analyses in the field of natural and agricultural sciences. The basic information about the location of the object in space gives the position determined in the geocentric reference system WGS84 (World Geodetic System). In practice, the spatial position of the object is often determined by means of single-frequency satellite receivers. The location of test polygons and measuring points using single-frequency satellite receivers can significantly simplify field research. The use of these types of receivers may, however, cause errors in the development of multiannual research and significantly influence the inference process. This applies in particular to researches that assume a cyclical analysis of the same test field or sampling at the same point. The simulation of the measurement of the surface area of the selected test field with a single-frequency code GPS receiver was performed based on synchronously recorded time series of coordinates of polygon vertices. The Garmin GPSMAP 62st receiver was used. The error of determining the surface area depending on the measurement time on the same polygon vertex was determined. An assessment of the benefits resulting from the application of the averaging of registered positions was also carried out and a method for correction of the shape of the measured polygon was proposed. The analyses carried out showed that increase of the measurement time at the point allows reducing the error of the determined position. The proposed method of correction of the shape of the measured polygon permits an improvement of its geometry and spatial orientation.