PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2018/04/21-22:57:50
G02     199.5          19.2               15.9 +/-    2.14      35.8 +/-    2.14  0.040 / 0.050
G06     171.7          51.1               13.1 +/-    0.60      16.3 +/-    0.60  0.050 / 0.050
G13     229.6          14.9               14.3 +/-    1.94      35.6 +/-    1.94  0.210 / 0.470
G17     10.3           65.2               10.2 +/-    0.55      11.2 +/-    0.55  0.150 / 0.630
G19     310.4          71.1               10.1 +/-    0.39      10.6 +/-    0.39  0.140 / 0.340
G24     311.8          27.5                9.5 +/-    1.59      17.6 +/-    1.59  0.180 / 0.380
G28     85.2           41.0               10.7 +/-    1.33      15.4 +/-    1.33  0.080 / 0.120
G30     156.3          15.8               15.2 +/-    2.25      37.2 +/-    2.25  0.090 / 0.110