PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2018/05/20-17:42:40
G01     120.0          17.3               12.0 +/-    1.54      28.1 +/-    1.54  0.020 / 0.040
G07     77.2           67.3               10.9 +/-    0.40      11.7 +/-    0.40  0.030 / 0.040
G08     46.1           34.4                9.3 +/-    0.42      14.9 +/-    0.42  0.040 / 0.070
G09     177.2          27.0               12.9 +/-    1.63      24.1 +/-    1.63  0.040 / 0.070
G11     109.2          39.5               12.4 +/-    1.20      18.1 +/-    1.20  0.030 / 0.070
G13     318.2          18.5               10.9 +/-    2.79      24.9 +/-    2.79  0.040 / 0.030
G17     202.4          20.9               13.1 +/-    0.65      28.2 +/-    0.65  0.040 / 0.060
G18     95.7           20.5               10.8 +/-    0.99      23.4 +/-    0.99  0.040 / 0.060
G28     291.3          57.1               12.3 +/-    0.60      14.4 +/-    0.60  0.040 / 0.080
G30     346.6          68.4               10.3 +/-    0.49      11.0 +/-    0.49  0.040 / 0.080