PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/12/21-09:28:00
G02     248.4          78.8                2.4 +/-    0.32       2.4 +/-    0.32  0.150 / 0.300
G05     171.4          17.2                2.2 +/-    1.23       5.1 +/-    1.23  0.120 / 0.240
G06     39.2           63.1                2.2 +/-    0.67       2.5 +/-    0.67  0.040 / 0.040
G12     321.2          51.7                2.5 +/-    0.50       3.0 +/-    0.50  0.040 / 0.040
G17     72.8           20.8                3.8 +/-    1.81       8.2 +/-    1.81  0.070 / 0.130
G19     59.7           36.8                2.0 +/-    1.79       3.0 +/-    1.79  0.070 / 0.130
G24     245.3          34.2                4.8 +/-    2.27       7.7 +/-    2.27  0.120 / 0.210
G25     317.0          13.7                2.9 +/-    1.77       7.4 +/-    1.77  0.140 / 0.270