PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/20-16:12:40
G01     68.3476        32.3048         13.3369 +/-  1.5905   22.2879 +/-  1.5905  0.080 / 0.160
G07     138.1804       25.7220         13.1170 +/-  1.0806   25.2113 +/-  1.0806  0.090 / 0.210
G11     51.3427        26.4359         10.3956 +/-  2.2618   19.6622 +/-  2.2618  0.060 / 0.120
G13     274.3653       36.6802         13.4330 +/-  0.9717   20.6767 +/-  0.9717  0.050 / 0.100
G15     304.5261       13.9965         11.7042 +/-  1.2933   29.8248 +/-  1.2933  0.050 / 0.100
G17     239.2539       73.3276         13.7861 +/-  0.3213   14.3260 +/-  0.3213  0.050 / 0.100
G19     225.8053       45.8338         14.0862 +/-  1.9475   18.7600 +/-  1.9475  0.050 / 0.070
G28     22.7103        58.7263         12.3346 +/-  3.3576   14.1689 +/-  3.3576  0.040 / 0.080
G30     136.3647       62.6867         13.3237 +/-  0.3545   14.7968 +/-  0.3545  0.030 / 0.020