PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2018/04/21-19:28:00
G01     125.0          13.4               18.8 +/-    2.59      48.5 +/-    2.59  0.040 / 0.060
G07     59.4           69.4               15.5 +/-    0.30      16.5 +/-    0.30  0.040 / 0.080
G08     50.5           40.9               14.5 +/-    0.59      20.8 +/-    0.59  0.150 / 0.400
G09     178.4          33.9               17.6 +/-    2.67      28.6 +/-    2.67  0.170 / 0.410
G11     117.4          36.4               17.2 +/-    0.53      26.6 +/-    0.53  0.080 / 0.100
G13     320.5          13.4               12.3 +/-    2.23      31.9 +/-    2.23  0.070 / 0.090
G17     201.8          13.5               21.1 +/-    1.90      54.3 +/-    1.90  0.040 / 0.060
G18     101.9          17.8               17.1 +/-    1.70      39.6 +/-    1.70  0.060 / 0.080
G28     281.0          54.5               16.7 +/-    0.93      20.0 +/-    0.93  0.040 / 0.030
G30     339.1          64.1               14.4 +/-    0.49      15.8 +/-    0.49  0.040 / 0.040