PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/12/21-11:12:30
G02     35.9           53.3                4.2 +/-    0.50       5.1 +/-    0.50  0.030 / 0.040
G05     138.3          62.7                6.1 +/-    1.04       6.8 +/-    1.04  0.030 / 0.040
G06     52.6           20.3                1.0 +/-    0.98       2.2 +/-    0.98  0.120 / 0.270
G12     202.6          68.1                3.2 +/-    0.47       3.4 +/-    0.47  0.110 / 0.220
G20     199.8          24.6                3.6 +/-    2.09       7.1 +/-    2.09  0.020 / 0.040
G25     295.8          54.0                4.4 +/-    0.77       5.3 +/-    0.77  0.030 / 0.040
G29     309.7          31.8                2.8 +/-    0.61       4.7 +/-    0.61  0.040 / 0.060