PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/20-22:28:00
G02     48.1           43.6               24.9 +/-   10.13      34.2 +/-   10.13  0.050 / 0.050
G05     89.0           70.3               17.1 +/-    1.91      18.1 +/-    1.91  0.050 / 0.050
G12     186.2          43.0               16.2 +/-    1.32      22.5 +/-    1.32  0.060 / 0.060
G20     201.9          49.6              -64.6 +/-   63.17     -82.0 +/-   63.17  0.060 / 0.060
G21     262.3          10.3               -1.9 +/-   28.70      -5.4 +/-   28.70  0.130 / 0.620
G25     247.4          58.0               17.2 +/-    0.89      19.9 +/-    0.89  0.130 / 0.520
G29     322.0          45.9               14.0 +/-    0.97      18.7 +/-    0.97  0.040 / 0.080