PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/20-10:57:50
G03     200.6737       39.4036          4.3300 +/-  0.7570    6.3600 +/-  0.7570  0.050 / 0.050
G07     275.6472       30.4666          4.4891 +/-  1.8447    7.7857 +/-  1.8447  0.040 / 0.040
G08     150.6434       14.9763          4.2269 +/-  1.8747   10.5199 +/-  1.8747  0.100 / 0.110
G09     319.3825       47.7044          2.6849 +/-  0.7365    3.4863 +/-  0.7365  0.120 / 0.110
G16     54.0179        55.6902          3.4044 +/-  0.6004    4.0275 +/-  0.6004  0.040 / 0.020
G22     181.1191       21.1179          2.6743 +/-  1.0103    5.7266 +/-  1.0103  0.030 / 0.030
G23     356.2326       76.7999          3.2705 +/-  0.8098    3.3500 +/-  0.8098  0.090 / 0.130
G26     43.8884        27.5253          1.5057 +/-  1.7248    2.7799 +/-  1.7248  0.080 / 0.130
G27     116.2742       24.5319          5.3968 +/-  0.9538   10.6592 +/-  0.9538  0.120 / 0.200