PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/20-18:42:10
G02     207.3612       39.0769         14.7638 +/-  1.3059   21.8039 +/-  1.3059  0.060 / 0.080
G06     134.7577       77.1427         13.6128 +/-  0.5486   13.9262 +/-  0.5486  0.050 / 0.080
G12     312.8286       23.6520         12.1249 +/-  1.8400   24.4432 +/-  1.8400  0.070 / 0.110
G17     46.1109        40.7620         11.3577 +/-  1.7417   16.3172 +/-  1.7417  0.090 / 0.110
G19     21.7432        58.3593         12.5862 +/-  1.0100   14.5070 +/-  1.0100  0.070 / 0.090
G28     110.8107       25.1034         13.8234 +/-  1.4734   26.9461 +/-  1.4734  0.040 / 0.070