PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/21-14:27:40
G01     118.8          17.9                9.5 +/-    1.60      22.1 +/-    1.60  0.110 / 0.130
G07     85.7           63.3               10.0 +/-    0.91      11.0 +/-    0.91  0.100 / 0.110
G08     44.6           29.7                7.1 +/-    1.17      12.5 +/-    1.17  0.030 / 0.030
G09     175.8          24.9               10.1 +/-    2.50      19.9 +/-    2.50  0.030 / 0.030
G11     103.3          38.3               10.1 +/-    0.65      15.1 +/-    0.65  0.030 / 0.030
G13     318.6          17.7                7.8 +/-    2.40      18.3 +/-    2.40  0.030 / 0.030
G17     201.0          26.9               10.0 +/-    1.78      18.7 +/-    1.78  0.170 / 0.190
G28     292.9          57.2                7.7 +/-    1.27       9.0 +/-    1.27  0.170 / 0.230
G30     342.2          66.4                9.4 +/-    0.38      10.2 +/-    0.38  0.120 / 0.140