Applications of Low-Cost GNSS Receivers for Positioning and Remote Sensing
- U-Blox M8T receiver (left) connected with Raspberry PI 3 Model B computer (right) in their cases.
- © Antonoglou (GFZ)
Nikolaos Antonoglou (Sucessful
finalization July 2018)
A U-Blox M8T Global Navigation Satellite System (GNSS) receiver and
a Raspberry Pi 3 board computer were used in order to construct a
low-cost GNSS data recorder. The goal of this procedure is to show
that the construction of this device is straightforward and it does
not require extended knowledge about electronics and programming. All
materials used for the construction are simple and cheap. The control
of the data recorder can be done by any smartphone.
Additionally, three different applications of these low-cost GNSS receivers were demonstrated through practical experiments. The first and the second experiment examine the accuracy of the positioning solutions of low-cost receivers in post-processing mode. The receiver was operated in dynamic mode and was attached to a bicycle and a unmanned aerial vehicle (UAV). The trajectories were calculated using two different methods, the absolute and the relative positioning. In addition, the antenna was connected to a second, geodetic, double-frequency receiver. This set-up made possible the direct comparison of the results of the low-cost receiver with these of the standard double-frequency one. The third experiment demonstrated an innovative GNSS remote sensing application, the determination of soil moisture with reffected signals in the direct vicinity of the receiver's antenna. In this case, two U-Blox M8T receivers were used to record GNSS measurements. The first one was connected to a low-cost antenna and the second one was connected to a geodetic one. Additionally, a double-frequency receiver was connected to the geodetic antenna with a splitter.
Apart from the equipment described above, a NavSpark-mini GNSS receiver with its own antenna was used too. Although this device is of lower quality, it provides signal strength measurements with higher numerical resolution than the other receivers, which is especially beneficial for remote sensing applications.