PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/20-12:57:30
G07     341.2019       60.4284          5.1903 +/-  0.4322    5.8725 +/-  0.4322  0.030 / 0.020
G08     93.6468        51.3150          6.9363 +/-  0.4682    8.6103 +/-  0.4682  0.030 / 0.020
G09     185.1284       71.2129          5.7609 +/-  0.7144    6.0497 +/-  0.7144  0.030 / 0.030
G11     142.2330       13.8251          6.5754 +/-  2.0969   16.8241 +/-  2.0969  0.030 / 0.040
G23     156.0969       41.8484          6.9603 +/-  0.8885    9.8296 +/-  0.8885  0.040 / 0.070
G27     53.1856        30.1186          6.3418 +/-  1.5937   11.0784 +/-  1.5937  0.050 / 0.080
G28     238.5374       30.5853          6.2149 +/-  0.6815   10.7526 +/-  0.6815  0.070 / 0.080
G30     301.4533       33.7063          1.5038 +/-  0.7982    2.4454 +/-  0.7982  0.090 / 0.090