PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2019/04/21-20:27:50
G01     66.9           32.1               12.7 +/-    1.58      21.3 +/-    1.58  0.110 / 0.130
G07     138.5          22.4               14.6 +/-    1.27      30.3 +/-    1.27  0.120 / 0.140
G11     50.8           28.0                9.2 +/-    1.62      16.7 +/-    1.62  0.030 / 0.040
G13     269.8          37.8               13.8 +/-    3.79      20.8 +/-    3.79  0.030 / 0.030
G15     299.1          16.1               10.9 +/-    2.73      26.3 +/-    2.73  0.060 / 0.060
G17     238.7          72.4               14.7 +/-    0.72      15.4 +/-    0.72  0.060 / 0.050
G18     45.1           15.2                9.9 +/-    1.74      24.5 +/-    1.74  0.150 / 0.390
G19     225.8          45.0               15.5 +/-    2.35      20.8 +/-    2.35  0.160 / 0.290
G28     16.2           60.2               12.4 +/-    1.18      14.1 +/-    1.18  0.070 / 0.110
G30     138.4          57.2               13.9 +/-    0.38      16.2 +/-    0.38  0.110 / 0.130