氣象用全球定位系統接收器(GPS/MET)

中華三號衛星為由八顆低軌道微衛星組成之星系衛星，主要酬載是在每顆衛星上安裝的四
個GPS天線，以接收現有之24顆GPS衛星L1及L2頻段訊號。由於GPS訊號傳播在穿過地球大

氣電離層及對流層時，會因大氣所產生的折射現象造成接收信號的時間延遲；由所實際量

到的訊號之時間延遲量或傳播路徑之折射角度，可以利用模式反演推算出訊號所穿過之電

離層及大氣層之電子密度、溫度、壓力、及水汽含量等資料，配合天氣預報作業，每3小

時提供更新資料，供數值天氣預報模式使用。

Global Positioning System (GPS) Meteorology is the application of GPS data to the monitoring and analyses of atmospheric conditions. Atmospheric monitoring can be done by both ground-based and space-based GPS applications.

GPS satellites transmit radio signals that can be inverted to measure atmospheric profiles of refractivity. The refractivity profile can be transformed to profiles of tropospheric humidity given a temperature profile.

Ground-based GPS receivers at fixed locations can be used to gather data that can be used to determine integrated Precipitable Water Vapor (PWV). Atmospheric scientists have shown that GPS-determined PWV observations can significantly improve weather forecasting accuracy.