## 4 Conclusions  
Based on the L-band satellite-ground clock offset data and the Ka-band inter-satellite clock offset data, this paper provides a method of whole-network adjustment for clock offset. In addition, the fitting residual, prediction error and closure error are used to evaluate and verify the effectiveness of this new method. This new method makes the RMS of the clock offset fitting residual reach up to 0.13 ns, which is lower than that of \"one-hop\" reduction by about 45.06%. As well, the RMS of clock offset prediction error hits about 0.25 ns, which is lower than those of only satellite-ground and \"one-hop\" reduction by about 62.13% and 52.15%, respectively. In addition, the closure error of inter-satellite station and three-satellite are approximate 0, which is much lower than 0.69 ns and 0.23 ns for \"one-hop\" reduction. This paper enriches the satellite navigation time synchronization system, and can be applied to clock offset measurement, systematic difference calculation \begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Statistical Results**} & **Closure Error of SGL+ISL** & **Closure Error of WNA** \\  & **Method** & **Method** \\ \hline Inter-satellite station & 0.69 & \(1.34\times 10^{-10}\) \\ Three-satellite & 0.23 & \(5.54\times 10^{-11}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 4: RMS statistical results of closure errors (unit. ns). \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline \multicolumn{1}{c}{} & & & \multicolumn{4}{c}{**Some Inter-Satellite Station Closure Errors**} & & \\ \hline \multirow{3}{*}{
\begin{tabular}{c} Station \\ code \\ \end{tabular} } & \multirow{3}{*}{Satellite 1 } & \multirow{3}{*}{Satellite 2 } & Closure error & \multirow{3}{*}{Satellite 1 } & \multirow{3}{*}{Satellite 2} & Closure error & \multirow{3}{*}{Satellite 1 } & Closure error & \multirow{3}{*}{Satellite 2} & \\  & & & & & & & & method & & WNA method \\ \cline{1-1} \cline{5-10} \multirow{3}{*}{1} & \multirow{3}{*}{C38} & \multirow{3}{*}{C39} & 0.89 & \(2.55\times 10^{-12}\) & 1 & C38 & C22 & 1.56 & \(4.85\times 10^{-11}\) \\  & & & & & & & & & \\ \cline{1-1} \cline{5-10} \multirow{3}{*}{1} & \multirow{3}{*}{C38} & \multirow{3}{*}{C40} & 1.03 & \(2.78\times 10^{-12}\) & 1 & C38 & C23 & 0.36 & \(6.25\times 10^{-11}\) \\  & & & & & & & & & \\ \cline{1-1} \cline{5-10} \multirow{3}{*}{1} & \multirow{3}{*}{C38} & \multirow{3}{*}{C25} & 1.07 & \(5.81\times 10^{-11}\) & 1 & C38 & C24 & 1.08 & \(6.79\times 10^{-11}\) \\  & & & & & & & & & \\ \cline{1-1} \cline{5-10} \multirow{3}{*}{1} & \multirow{3}{*}{C38} & \multirow{3}{*}{C26} & 1.62 & \(6.33\times 10^{-11}\) & 1 & C38 & C32 & 0.65 & \(9.49\times 10^{-11}\) \\  & & & & & & & & & \\ \cline{1-1} \cline{5-10} \multirow{3}{*}{1} & \multirow{3}{*}{C38} & \multirow{3}{*}{C27} & 0.90 & \(7.28\times 10^{-12}\) & 1 & C38 & C33 & 2.06 & \(5.06\times 10^{-11}\) \\  & & & & & & & & & \\ \cline{1-1} \cline{5-10} \multirow{3}{*}{1} & \multirow{3}{*}{C38} & \multirow{3}{*}{C39} & 1.02 & \(6.98\times 10^{-12}\) & 1 & C38 & C35 & 0.82 & \(3.21\times 10^{-11}\) \\  & & & & & & & & & \\ \cline{1-1} \cline{5-10} \multirow{3}{*}{1} & \multirow{3}{*}{C38} & \multirow{3}{*}{C30} & 0.44 & \(2.64\times 10^{-11}\) & 1 & C38 & C37 & 0.81 & \(4.99\times 10^{-11}\) \\  & & & & & & & & & \\ \cline{1-1} \cline{5-10} \multirow{3}{*}{1} & \multirow{3}{*}{C38} & \multirow{3}{*}{C19} & 0.72 & \(2.42\times 10^{-11}\) & 1 & C38 & C41 & 0.26 & \(5.21\times 10^{-12}\) \\  & & & & & & & & & \\ \cline{1-1} \cline{5-10} \multirow{3}{*}{1} & \multirow{3}{*}{C38} & \multirow{3}{*}{C20} & 0.80 & \(4.41\times 10^{-11}\) & 1 & C38 & C42 & 0.28 & \(8.31\times 10^{-12}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: RMS statistical results of some inter-satellite station and three-satellite closure errors (unit: ns). and so forth. Furthermore, it provides a theoretical basis for effectively resolving systematic deviations in satellite-ground links and inter-satellite links.