PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2018/04/20-14:13:00
G01     230.3          20.7                7.0 +/-    1.53      15.2 +/-    1.53  0.070 / 0.160
G03     294.6          66.8                5.5 +/-    0.70       5.9 +/-    0.70  0.060 / 0.160
G14     80.2           30.5                6.7 +/-    0.56      11.6 +/-    0.56  0.050 / 0.110
G16     149.4          40.7                8.1 +/-    0.67      11.7 +/-    0.67  0.060 / 0.090
G18     207.2          10.9                7.6 +/-    4.20      20.8 +/-    4.20  0.070 / 0.150
G22     212.5          73.0                7.2 +/-    0.79       7.5 +/-    0.79  0.080 / 0.160
G23     306.0          37.6                5.4 +/-    1.03       8.1 +/-    1.03  0.040 / 0.090
G26     103.7          52.6                7.1 +/-    0.60       8.6 +/-    0.60  0.060 / 0.110
G31     44.0           34.8                5.6 +/-    0.93       8.9 +/-    0.93  0.040 / 0.050