PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/08/20-13:27:30
G01     89.7           31.7                7.2 +/-    1.41      12.2 +/-    1.41  0.030 / 0.050
G07     125.9          42.4                8.6 +/-    0.52      12.0 +/-    0.52  0.040 / 0.040
G11     66.9           37.3                8.0 +/-    1.01      12.2 +/-    1.01  0.020 / 0.020
G13     296.5          34.7                5.4 +/-    3.08       8.6 +/-    3.08  0.020 / 0.020
G17     214.2          56.4                7.7 +/-    0.76       9.0 +/-    0.76  0.040 / 0.040
G19     214.5          29.0                6.8 +/-    1.54      12.1 +/-    1.54  0.030 / 0.040
G28     349.8          61.6                5.8 +/-    0.71       6.5 +/-    0.71  0.070 / 0.090
G30     97.7           77.7                7.7 +/-    0.62       7.8 +/-    0.62  0.080 / 0.100