Low-cost GPS/GNSS Real Time Kinematic receiver to build a cartographic grid on the ground for an archaeological survey at Piscina Torta (Italy)

The collection of samples and finds for archaeological surveys is traditionally based on the establishment of grids that allow the area under study to be discretized into generally square cells in order to allow a statistical assessment of the highest or lowest concentration of finds. Currently, such grids are implemented in a local coordinate system established by means of total stations or tape measures. We validated the capabilities of a low-cost GPS/GNSS Real Time Kinematic (RTK) receiver to build a grid during the intensive archaeological survey of the Piscina Torta site (Italy), in the framework of the Salt and Power project of the University of Groningen. We also tested not using a local grid but a cartographic grid (WGS84 UTM zone 33 N) and naming the single cells with the coordinates of one of its vertices. This approach is greatly facilitated by the recent availability of inexpensive RTK receivers with few centimetres accuracy, very small in size and weight and with hardware protected enough to be used in the field. This would facilitate the use and exchange of the data (e.g. about the materials collected in the cell) among the scientific community and can be thought of as a proposal for standardization.