PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/20-13:42:40
G07     26.5184        67.9037          8.1674 +/-  0.8179    8.7421 +/-  0.8179  0.060 / 0.060
G08     61.4263        46.3383          6.8738 +/-  1.0782    9.0910 +/-  1.0782  0.060 / 0.050
G09     178.0751       48.2821          9.6257 +/-  0.6087   12.4053 +/-  0.6087  0.020 / 0.030
G11     126.8373       26.8483          7.6312 +/-  0.9537   14.3017 +/-  0.9537  0.030 / 0.030
G23     160.4121       20.7120          6.8928 +/-  1.3115   14.9058 +/-  1.3115  0.100 / 0.200
G27     40.1667        16.0979          7.7094 +/-  1.3525   18.6693 +/-  1.3525  0.140 / 0.230
G28     259.3686       45.4924          7.9701 +/-  1.1825   10.6653 +/-  1.1825  0.100 / 0.130
G30     318.3661       48.3613          6.0794 +/-  0.5387    7.8268 +/-  0.5387  0.070 / 0.250