## 4 Zero-Baseline Instantaneous RTK Positioning with Smartphones in Lying Down and Upright Positions
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multirow{3}{*}{**Baselines**} & \multirow{3}{*}{**Setup**} & \multirow{3}{*}{\begin{tabular}{c} **ILS SR** \\ **(\%)** \\ \end{tabular} } & \multirow{3}{*}{\begin{tabular}{c} **Avg. \#** \\ **of Sat.** \\ \end{tabular} } & \multicolumn{6}{c}{**Mean \(\pm\) STDs (m)**} & \multicolumn{6}{c}{**GPS**} & \multicolumn{6}{c}{**QZSS**} \\ \cline{5-11}  & & & & & **Correctly Fixed** & **Float** & **L1** & **L2** & **L5** & **L1** & **L2** & **L5** \\ \hline \multirow{3}{*}{GPD1–GPD2} & \multirow{3}{*}{upright} & \multirow{3}{*}{99.9} & \multirow{3}{*}{21} & E & 0.000 \(\pm\) 0.001 & \(-\)0.014 \(\pm\) 0.580 & \multirow{3}{*}{2.003} & \multirow{3}{*}{-} & 0.003 & 0.004 & \multirow{3}{*}{-} & 0.003 \\  & & & N & 0.000 \(\pm\) 0.001 & 0.004 \(\pm\) 0.702 & & & [2.479] & & [0.243] & [2.319] & & [0.003 [0.248]] \\ \hline \multirow{3}{*}{GPD1–GPD2} & \multirow{3}{*}{\
\begin{tabular}{c} lying \\ down \\ \end{tabular} } & \multirow{3}{*}{99.9} & \multirow{3}{*}{23} & E & 0.000 \(\pm\) 0.001 & 0.006 \(\pm\) 0.599 & \multirow{3}{*}{2.005} & \multirow{3}{*}{-} & 0.004 & 0.004 & \multirow{3}{*}{-} & 0.004 \\  & & & N & 0.000 \(\pm\) 0.002 & & \(-\)0.005 \(\pm\) 0.627 & & [0.2543] & & [0.004 [0.312]] & & [0.004 [0.274]] \\ \hline \multirow{3}{*}{SGD1–SGD2} & \multirow{3}{*}{upright} & \multirow{3}{*}{97.8} & \multirow{3}{*}{13} & E & 0.000 \(\pm\) 0.001 & 0.005 \(\pm\) 0.338 & \multirow{3}{*}{1.005} & \multirow{3}{*}{-} & 0.005 & 0.005 & \multirow{3}{*}{-} & 0.006 \\  & & & N & 0.000 \(\pm\) 0.001 & & \(-\)0.011 \(\pm\) 0.411 & & [1.401] & & [1.119] & [1.043] & & [0.006 [0.932]] \\ \hline \multirow{3}{*}{SGD1–SGD2} & \multirow{3}{*}{
\begin{tabular}{c} lying \\ down \\ \end{tabular} } & \multirow{3}{*}{79.4} & \multirow{3}{*}{17} & E & 0.000 \(\pm\) 0.002 & \(-\)0.019 \(\pm\) 0.473 & \multirow{3}{*}{0.012} & \multirow{3}{*}{-} & 0.016 & 0.013 & \multirow{3}{*}{-} & 0.013 \\  & & & N & 0.001 \(\pm\) 0.002 & & \(-\)0.001 \(\pm\) 0.555 & & [2.053] & & [2.028] & [1.735] & & [1.644] \\ \hline \multirow{3}{*}{TRM1–TRM2} & \multirow{3}{*}{upright} & \multirow{3}{*}{99.9} & \multirow{3}{*}{25} & E & 0.000 \(\pm\) 0.001 & 0.004 \(\pm\) 0.215 & \multirow{3}{*}{0.004} & \multirow{3}{*}{0.003} & \multirow{3}{*}{-} & 0.006 & 0.002 & \multirow{3}{*}{-} \\  & & & N & 0.000 \(\pm\) 0.001 & & 0.000 \(\pm\) 0.238 & & [0.586] & [0.525] & & [0.569] & [0.404] & \\ \hline \multirow{3}{*}{UBX1–UBX2} & \multirow{3}{*}{upright} & \multirow{3}{*}{100.0} & \multirow{3}{*}{25} & E & 0.000 \(\pm\) 0.001 & \(-\)0.027 \(\pm\) 0.158 & \multirow{3}{*}{0.005} & \multirow{3}{*}{0.005} & \multirow{3}{*}{-} & 0.004 & 0.004 \\  & & & N & 0.000 \(\pm\) 0.001 & & 0.032 \(\pm\) 0.198 & & [0.303] & [1.022] & & [0.441] & [0.843] & \\ \hline \multirow{3}{*}{**Note:** The dashes indicate when the L2/L5 DD phase/code residuals are not tracked in our zero-baseline setup. Note that the Galileo MEO satellites have a repeatability of every tenth sideral day and the BDS MEO satellites every eleventh day, and these GNSSs are thus excluded from the comparison. The mean RMS values of the DD phase and code residuals are determined based on the period stated in Table 2. Finally, Avg. # of sat. denotes the average number of satellites over the entire observation time-span.  
\end{table} 
Table 3: Empirical ILS SR for instantaneous zero-baseline dual-frequency RTK positioning and 12 h of data (cf. Figure 2). The instantaneous (single-epoch) emperical mean and STDs (East, North and Up) of the correctly fixed and float positioning errors are also shown. The mean RMSs of the DD phase (code within square bracket) residuals are also depicted in the last column for GPS and QZSS that repeat between the datasets (cf. Table 2). in lying down and upright positions, are given in Table 3. This is given together with the mean of the root mean square (RMS) values of the DD phase and code residuals of each GNSS that repeat between datasets (cf. Table 2).