## Conclusions: Low Temperature
### High Temperature: \(22\,^{\circ}\)C-\(40\,^{\circ}\)C
#### 7.3.3 A2t-Ftsp
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Temperature** & **Protocol** & **Average Error** & **Avg.** & \(<\)**95\% Error** & \(<\)**95\%** \\
**Range** & & **ticks** & **ppm** & **ticks** & **ppm** \\ \hline \multirow{3}{*}{**Low**} & AT-FTSP & \(\pm 0.78\) tics & 0.05 ppm & \(\pm 3.22\) tics & 0.21 ppm \\  & A2T-FTSP & \(\pm 0.73\) tics & 0.04 ppm & \(\pm 2.75\) tics & 0.18 ppm \\ \hline \multirow{3}{*}{**Intermediate**} & AT-FTSP & \(\pm 1.15\) tics & 0.07 ppm & \(\pm 5\) tics & 0.33 ppm \\  & A2T-FTSP & \(\pm 0.85\) tics & 0.05 ppm & \(\pm 7\) tics & 0.23 ppm \\ \hline \multirow{3}{*}{**High**} & AT-FTSP & \(\pm 1.34\) tics & 0.09 ppm & \(\pm 12\) tics & 0.4 ppm \\  & A2T-FTSP & \(\pm 0.67\) tics & 0.04 ppm & \(\pm 2.75\) tics & 0.18 ppm \\ \hline \hline \end{tabular}
\end{table} 
Table 6: General results. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Protocol** & \(<\)**95\% Error** & \(<\)**95\%** \\  & **ticks** & **ppm** \\ \hline EACS & N/A & 8 ppm * \\ TCTS & \(\pm 4\) tics & 0.37 ppm \\ AT-FTSP & \(\pm 6.74\) tics & 0.31 ppm \\ A2T-FTSP & \(\pm 4.16\) tics & 0.19 ppm \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Comparative results. EACS, Environment-Aware Clock Skew Estimation and Synchronization for WSN; TCTS, Temperature Compensated Time Synchronization. (\(122\)\(\mu\)s). Taking into account these values, the clock stability is, approximately, \(0.37\) ppm. However, for very large periods of resynchronization, the authors obtained \(<\) 0.07 ppm (\(4\) ms of error in a \(16\) h period). On the other hand, the proposed AT/A2T-FTSP methods have obtained similar values in clock stability terms as TCTS for large resynchronization periods. TCTS provided very good results under simulation; however, real-world scenarios include many uncertainties that modify the results from the ideal simulation. Those variations from the simulation results to the real-world experiments have been clearly stated in EACS, where simulation provided an error of \(2\) ms, while in the experimental setup, that error went up to \(8\) ms. In this work, all the results are obtained in a real environment and not a simulated one. Nevertheless, the real-world results from AT/A2T are in the same range as the simulation results from TCTS. It is worth noting that neither AT nor A2T require any calibration period, meanwhile TCTS uses 24 h to obtain a good calibration phase. Besides, as the proposed methods use a \(1\) MHZ timer compensated for by the \(32\) KHZ oscillator, microsecond accuracy can be achieved. For the sake of comparison, errors are provided in terms of \(1\) MHZ clock ticks in Table 6. In that table, average synchronization is used to compute a \(1\)-MHZ tic error. Besides, a maximum error in \(95\%\) of periods (the same methodology as described in TCTS) is used to provide another measure of error ticks in a \(1\) MHZ clock. These results clearly show the accuracy of the proposed methods and outperforms the previous approaches for the experimental setup described in this work. The simplicity of the proposed methods makes these less computationally demanding than the previous approaches. Besides, the proposed methods do not require any calibration period for temperature compensation. Finally, they are able to deal with dynamic reference node swapping, which was not feasible in previous approaches.