## 2 Materials and Methods
### Input Parameters  
Input parameters are entered using the panel on the left side of the software window (Figure 2). Figure 1: The main window of the software for the planning of a linear object GNSS measurement campaign. The \"Start date\" [1] sets the beginning of the campaign time frame. The planned campaign will not commence before this date. The \"Duration\" [2] determines the max duration of the GNSS measurement campaign. The \"Velocity\" [3] is the average velocity of the inspection vehicle in motion, expressed in kilometres per hour. The \"Sample period\" [4] determines the time resolution of calculations made by the software. In combination with velocity, it also sets the spatial resolution of the analysis being carried out. The lower the value, the higher the quality of the schedule obtained. However, lowering the sample period value increases the duration of calculations dramatically. The value should be adjusted to the specificity of the inspection vehicle and its manoeuvring capabilities, as well as to the operating frequency of instruments. The \"Min. elevation\" [5] limits from below the angular height of the satellite in relation to the inspection vehicle. The satellites visible at a lower angle will be regarded as if they are remaining below the horizon and will not be considered in calculations. The \"Maximal DOP\" [6] determines the max value of the geometric coefficient that will be taken into account when mapping the optimal route. If the algorithm calculates that at a particular location and time that the DOP value obtained would be higher than that specified in this parameter, it will be assumed that the position at this point cannot be determined. Setting this value allows the \"bottleneck effect\" to be avoided. For certain points that are characterised by a great number of field obstacles, all satellites are only visible in narrow time windows. Usually, even then, the quality of positions obtained is not satisfactory. The algorithm, however, prefers to wait for such a window in order to obtain a finite (although extremely high) DOP value. This may lead to the degeneration of the optimal route. In order to avoid this problem, the parameter value being described should be set appropriately. The switch found next to the parameter value determines if it should be used. When selecting the value, the DOP assessment table can be used (Table 2) [49; 50; 51]. Figure 2: Input parameters of the software. The \"Constellations\" [7] enable the selection of a set of GNSS systems used in the campaign planning. Four main global systems are available (GPS, GLONASS, BDS, and Galileo). The \"DOP\" [8] area enables the selection of the geometric coefficient used during the planning. The DOP should correspond to the intended use of the measurement campaign. GDOP is the most general coefficient that estimates the constellation position quality simultaneously in the horizontal, vertical, and temporal dimensions. The equally often applied DOP is the PDOP, which assesses the distribution of constellations in a three-dimensional space. For the determination of the DOP value exclusively on the horizontal plane, HDOP is used. Its equivalent on the vertical plane is the VDOP. The accuracy of determining the clock offset is specified by the TDOP. The determined schedule will differ depending on the coefficient used. The \"Orbit data source\" [9] area includes two options. The first option, described as \"Laika\", enables the downloading of precise orbit data in the SP3 format directly from the National Aeronautics and Space Administration (NASA) servers (for the GPS constellation) or the Information and Analysis Center for Positioning, Navigation and Timing (IAC PNT) (for the other constellations). This method requires an Internet connection and can last for up to several min. It can also be temporarily unavailable due to maintenance works on the above-mentioned servers. The selection of the \"Almanac\" option enables the use of files in the Trimble Almanac format.