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          8.2380 +/-  0.8628    8.8176 +/-  0.8628  0.080 / 0.160
G08     61.4263        46.3383          6.7927 +/-  0.4007    8.9838 +/-  0.4007  0.060 / 0.130
G09     178.0751       48.2821          9.1885 +/-  1.1572   11.8418 +/-  1.1572  0.070 / 0.180
G11     126.8373       26.8483          9.2458 +/-  0.7655   17.3276 +/-  0.7655  0.070 / 0.160
G23     160.4121       20.7120          8.5492 +/-  1.1738   18.4879 +/-  1.1738  0.030 / 0.050
G27     40.1667        16.0979          6.9715 +/-  1.1395   16.8825 +/-  1.1395  0.020 / 0.070
G28     259.3686       45.4924          7.4381 +/-  0.7505    9.9534 +/-  0.7505  0.040 / 0.050
G30     318.3661       48.3613          4.9851 +/-  0.7892    6.4181 +/-  0.7892  0.050 / 0.050