PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/20-13:12:30
G07     353.9474       63.6071          6.6947 +/-  0.5408    7.3820 +/-  0.5408  0.020 / 0.020
G08     81.7891        51.3486          5.4399 +/-  0.6357    6.7502 +/-  0.6357  0.030 / 0.020
G09     180.9837       63.5620          6.5282 +/-  0.6179    7.2009 +/-  0.6179  0.030 / 0.030
G11     137.5006       18.1336          7.6761 +/-  1.6537   17.6811 +/-  1.6537  0.040 / 0.030
G23     158.0634       34.6140          6.7025 +/-  0.5005   10.7137 +/-  0.5005  0.070 / 0.090
G27     47.6562        25.9786          6.2449 +/-  1.7111   11.9336 +/-  1.7111  0.060 / 0.110
G28     244.5864       35.8660          7.8566 +/-  1.9043   12.2716 +/-  1.9043  0.150 / 0.090
G30     306.9429       38.3846          3.7791 +/-  1.0152    5.6468 +/-  1.0152  0.150 / 0.080