# Study on the Deployment of Ultra-Wideband Positioning Base Stations in Pig Farms
## 4 Experimental Analyses
### Analysis of Real Measurement Experiments  
The actual measurement experiments were conducted using LinkTrack P-A module hardware, which was utilized for both static fixed-point localization and dynamic following localization in an unobstructed open field enclosed by the base stations. Additionally, the size of the test site was adjusted based on the experimental variables required. Static positioning analysis  
For the square quadrilateral area surrounded by four base stations, measurements were taken at points located approximately 75 cm from each base station, as well as at the midpoint between two adjacent base stations and the midpoint of the quadrilateral itself, resulting in a total of thirteen data points. Similarly, for the square trilateral area enclosed by three base stations, measurements were obtained near 75 cm from each base stations, at the midpoint between two adjacent base stations, and at the centroid of the triangle formed by these three stations, yielding a total of ten data points. Each fixed point was sampled within a duration of three minutes with a sampling frequency set to 10 Hz. Different heights of base stations  
The UWB positioning effect is evaluated by enclosing the base stations in a square configuration with a spacing of 300 cm while varying the height of the base station at intervals of 0 cm, 75 cm, 125 cm, 175 cm, 225 cm, and 275 cm. The layout of the base stations are illustrated in Figure 7, wherein A\({}_{0}\) to A\({}_{3}\) represent the respective coordinate positions of each base station. Figures 7-9 show that when H is 0 cm or 275 cm, the deviation of each point is larger; when H is 175 cm or 225 cm, the deviation is smaller, and the root-mean-square error is within 15 for more points; when H is 125 cm or 175 cm, the variance is smaller for both, and within 2 for more points; when H is 275 cm, the variance is larger for more points. The same height and point location show that the X and Y coordinate variances are approximate. \begin{table}
\begin{tabular}{c c c c c c} \hline
**DOP** & **Targets** & **Scenario a** & **Scenario b** & **Scenario c** & **Scenario d** \\ \hline \multirow{3}{*}{HDOP} & Maximum & 2.50 & 1.48 & 2.13 & 2.13 \\  & Minimum & 1.18 & 1.02 & 1.06 & 1.06 \\  & Average & 1.84 & 1.25 & 1.59 & 1.59 \\  & Maximum & 14.47 & 3.77 & 8.47 & 8.47 \\  & Minimum & 0.99 & 0.99 & 0.98 & 0.98 \\  & Average & 7.73 & 2.38 & 4.73 & 4.73 \\  & Maximum & 14.69 & 3.96 & 8.69 & 8.69 \\ PDOP & Minimum & 1.90 & 1.58 & 1.58 & 1.58 \\  & Average & 8.30 & 2.77 & 5.13 & 5.13 \\ \hline \end{tabular}
\end{table} 
Table 3: DOP values for simulation experiments with different shapes. Figure 7: Positioning effect when the height of the base stations is different. Figure 8: Root-mean-square error at each point with different heights of the base stations. Table 4 shows that H is 75 cm for the X maximum value and the average value of the smallest, H is 125 cm for the X minimum value of the smallest, H is 0 cm for the X minimum value of the largest, H is 275 cm for the average value of the largest, H is 125 cm for the Y maximum value of the smallest, H is 125 cm for the Y minimum value and the average value of the smallest, H is 275 cm for the Y maximum value for the average value of the largest, and H is 0 cm for the Y minimum value of the smallest. Figure 9: Variance plots for points with different heights of the base stations. Figure 11: Root-mean-square error at each point when base station spacing is different. Figure 10: Effect of different spacing of base stations and simultaneous positioning. Table 6 shows that when L is 600 cm, the maximum value of X is the smallest; when L is 900 cm, the minimum value of X and the average value are the smallest; when L is 300 cm, the maximum value of Y is the smallest; when L is 900 cm, the minimum value of Y is the smallest; and when L is 600 cm, the average value of Y is the smallest.