PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/21-12:57:30
G07     344.4          61.3                5.5 +/-    0.91       6.2 +/-    0.91  0.040 / 0.020
G08     90.4           51.5                6.0 +/-    1.04       7.4 +/-    1.04  0.030 / 0.030
G09     183.5          69.1                8.0 +/-    0.33       8.4 +/-    0.33  0.070 / 0.090
G11     141.0          15.0                6.6 +/-    2.18      16.5 +/-    2.18  0.070 / 0.090
G23     156.7          39.9                7.6 +/-    0.99      11.0 +/-    0.99  0.040 / 0.040
G27     51.6           29.1                6.2 +/-    2.30      11.0 +/-    2.30  0.030 / 0.030
G28     240.1          32.1                7.5 +/-    1.73      12.5 +/-    1.73  0.050 / 0.070
G30     302.9          35.0                4.3 +/-    1.80       6.8 +/-    1.80  0.060 / 0.080