PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2018/04/20-18:57:40
G07     13.7           68.0               12.5 +/-    0.67      13.4 +/-    0.67  0.170 / 0.400
G08     67.5           51.2               11.9 +/-    1.02      14.8 +/-    1.02  0.190 / 0.320
G09     180.6          50.5               14.4 +/-    1.34      18.0 +/-    1.34  0.040 / 0.050
G11     132.0          26.8               14.4 +/-    1.53      27.1 +/-    1.53  0.040 / 0.050
G18     115.4          10.0               -0.8 +/-   31.15      -2.1 +/-   31.15  0.190 / 0.300
G23     158.5          15.7               15.5 +/-    1.59      38.0 +/-    1.59  0.180 / 0.360
G27     40.4           16.9                9.5 +/-    2.20      22.5 +/-    2.20  0.040 / 0.030
G28     259.0          45.7               13.8 +/-    1.91      18.4 +/-    1.91  0.030 / 0.030
G30     321.7          51.9               11.1 +/-    0.86      13.7 +/-    0.86  0.130 / 0.100