# GNSS Signal Quality in Forest Stands for Off-Road Vehicle Navigation
## 3 Results  
The results of the presented research included targeting and displaying tree positions without measuring eccentricity (the distance was measured on a reflecting prism attached to the side of the tree and the azimuth to the center of the tree). Furthermore, the tracks along which the vehicle moved were targeted and marked by tachymetry and its positions were measured (Figures 6 and 7). Additionally presented analyses include the quality of the GNSS signal during vehicle travel (Figures 8 and 9), determination of the number of satellites during the course (Figures 10 and 11), and determination of the estimation of receiver positioning accuracy (\(\sigma_{HZ}\)) and position deviations (\(d_{\rm HZ}\)) detected as the difference between the position recorded by the GNSS receiver and the position determined terrestrially (Figures 12-16 and Tables 1 and 2). Figure 5: Methodology of determining the accuracy of off-road vehicle navigation using GNSS. Figure 6: Tree positions in area 1—deciduous forest (Ortophoto C�ZK). Figure 7: Tree positions in area 2—mostly coniferous forest (Ortophoto C�ZK). FON:-Begin-Line-Feature:...Time: 25.08.2020-8:03:06,000...Version:.45 ATT:-Feature...Description:-2-sekundy...ID: 0003...Flags:...0-hex9 STR:Time-of-Week:25.08.2020-8:08:05,000...Vozidid:...cytrok145 SGH:Time:-25.08.2020-8:03:06,000...Sigma-North:-2,177...Sigma-East:-1,691...5 Sigma-Up:-4,8619 P05:...U:...25.08.2020-8:03:06,000...642993,175:...5466237,117:...457,9379 OSS:Time:25.08.2020-8:03:07,000...Clock-Blas:-3 119,015:Meters...No.-of-SVs:245 OSS:Time:25.08.2020-8:03:08,000...Clock-Blas:-3 174,421:Meters...No.-of-SVs:245 OSS:Time:25.08.2020-8:03:08,000...Sigma-North:-2,178...Sigma-East:-1,686...5 Sigma-Up:-4,8199 POS:...U:...25.08.2020-8:03:08,000...642993,142:...5466237,117:...457,9309 OSS:Time:25.08.2020-8:03:09,000...Clock-Blas:-3 229,755:Meters...No.-of-SVs:245 OSS:Time:25.08.2020-8:03:10,000...Clock-Blas:-3 285,983:Meters...No.-of-SVs:245 OSS:Time:25.08.2020-8:03:10,000...Clock-Blas:-3 340,273:Meters...No.-of-SVs:245 OSS:Time:25.08.2020-8:03:12,0000.Clock-Blas:-3 395,497:Meters...No.-of-SVs:245 OSS:Time:25.08.2020-8:03:12,0000.Sigma-North:-3,133:...5123=East:-2,393:...5123=Up:-9,4779 OSS:Time:25.08.2020-8:03:12,0000.\(\sim\)42991,159:...5466235,623:...458,9309 OSS:Time:25.08.2020-8:03:13,0000.\(\sim\)4369,690:Meters...No.-of-SVs:245 OSS:Time:25.08.2020-8:03:14,0000.\(\sim\)5123=North:-3,160...Sigma-East:-2,169...5 Sigma-Up:-9,7269 OSS:Time:25.08.2020-8:03:00:00,000.Clock-Blas:-3 229,755:Meters...No.-of-SVs:245 OSS:Time:25.08.2020-8:03:10,000.\(\sim\)5123=North:-3,133:...5123=East:-2,393:...5123=Up:-9,4779 OSS:Time:25.08.2020-8:03:12,000.\(\sim\)42991,159:...5466235,623:...458,9309 OSS:Time:25.08.2020-8:03:13,000.\(\sim\)4369=3.3 450,690:Meters...No.-of-SVs:245 OSS:Time:25.08.2020-8:03:14,000.\(\sim\)5123=North:-3,160...Sigma-East:-2,169...5 Sigma-Up:-9,7269 OSS:Time:25.08.2020-8:03:14,000.\(\sim\)5123=North:-3,160...Sigma-East:-2,169...5 Sigma-Up:-9,7269 OSS:Time:25.08.2020-8:03:00,000.Clock-Blas:-3 229,755:Meters...No. Figure 10: _Cont._  
Figure 11: Number of individual GNSS satellites during measurement in area 2. Figure 10: Number of individual GNSS satellites during measurement in area 1. Figure 12: Comparison of \(d_{Hz}\) horizontal deviations (red squares) with \(d_{Hz}\) horizontal errors (green color) derived from GNSS file data—area 1. Figure 14: The principle of estimating the accuracy of the vehicle path from GNSS measurements. Figure 13: Comparison of \(d_{Hz}\) horizontal deviations (red squares) with \(d_{Hz}\) horizontal errors (green color) derived from GNSS file data—area 2. Figure 15: Projected routes (broken line) and GNSS focused route (blue triangles). Figure 6:0 Horizontal errors \(\sigma_{Hz}\) obtained from GNSS measurements (blue circles).