PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2018/05/20-17:13:10
G07     38.2           69.8                9.4 +/-    0.76      10.0 +/-    0.76  0.040 / 0.050
G08     55.5           44.8                9.4 +/-    0.83      12.7 +/-    0.83  0.040 / 0.050
G09     178.7          40.7               10.8 +/-    1.41      15.6 +/-    1.41  0.030 / 0.030
G11     123.7          32.5               10.4 +/-    0.75      17.3 +/-    0.75  0.040 / 0.030
G18     108.0          14.5               10.6 +/-    1.52      26.6 +/-    1.52  0.170 / 0.290
G27     37.8           10.3                8.1 +/-    2.90      22.5 +/-    2.90  0.200 / 0.330
G28     270.2          50.7               11.6 +/-    2.48      14.5 +/-    2.48  0.030 / 0.020
G30     329.2          57.7                8.8 +/-    0.29      10.2 +/-    0.29  0.030 / 0.030