实时GPS水汽探测技术中的电离层延迟订正

Correction of Ionospheric Delay in Real-Time GPS Water Vapor Detection

在水汽监测网中,利用精密预报星历得到的结果与精密星历的结果相差很小,因此可以采用精密预报星历进行实时的水汽探测。由于电离层延迟对水汽影响较大,因此必须加以消除。详细地介绍了Klobuchar模型、双频观测值求解电离层延迟和双频观测值线性组合无电离层延迟3种方法的推导过程。将3种方法消除电离层延迟的影响大小作一比较,认为双频观测值线性组合无电离层延迟是最好的方法。

The difference between the results from the precisely predicted ephemeris and precise ephemeris is very small in the water vapor monitoring network, so the precisely predicted ephemeris can be used to detect water vapor in real time. Because the ionospheric delay has great effect on water vapor, it should be eliminated. The derivation processes of three methods （Klobuchar model, dual-frequency measurements and linearly com- bined double frequency measurements without ionospheric delay） are described. The effects of ionospheric delay eliminated by these three methods are compared, and the results indicate that the combined method is the best.