改良式模稜函數應用於台灣地區GNSS定位研究

Applying Modified Ambiguity Function Approach to GNSS Positioning in Taiwan

GLONASS衛星系統現已穩定運行，且提供全世界免費服務，目前已是最有潛力與GPS進行整合的導航衛星系統。其FDMA訊號特性，使得求解方式有別於CDMA系統，以致兩系統間整合更是深具挑戰。本文即在探討以改良式模稜函數法，在保有相位模稜的整數特性狀態下，直接對坐標分量進行解算。本實驗以GLONASS與GPS衛星系統為對象，以短基線定位與應用電離層模型TWIM於較長基線的改正等進行討論。實驗結果可以發現在台灣地區目前GLONASS系統已有很不錯的表現。配合TWIM模型改正，此方法在55公里基線，GPS系統可達平面定位精度約7公分，高程方向約14公分。GLONASS系統平面定位精度約12公分，高程方向約23公分。 GLONASS have been operated stably and provided free service worldwide. Currently, it is themost potential satellite system to integrate with GPS. Otherwise, the FDMA signal structure, which isdifferent from CDMA, makes integrations full of challenge.The proposed method generates the solution of geometry in the condition of preservinginteger-valued ambiguity. The experiments used GLONASS and GPS observations to compare withdifferent baseline lengths, and TWIM corrections in longer baseline positioning results. The resultsshow that GLONASS have good performance in Taiwan region. With TWIM corrections in 55 kmbaseline, the GPS positioning differences is 7 cm in horizontal and 14 cm in vertical component.GLONASS positioning differences is 12 cm in horizontal and 23 cm in vertical component.

GLONASS have been operated stably and provided free service worldwide. Currently, it is themost potential satellite system to integrate with GPS. Otherwise, the FDMA signal structure, which isdifferent from CDMA, makes integrations full of challenge.The proposed method generates the solution of geometry in the condition of preservinginteger-valued ambiguity. The experiments used GLONASS and GPS observations to compare withdifferent baseline lengths, and TWIM corrections in longer baseline positioning results. The resultsshow that GLONASS have good performance in Taiwan region. With TWIM corrections in 55 kmbaseline, the GPS positioning differences is 7 cm in horizontal and 14 cm in vertical component.GLONASS positioning differences is 12 cm in horizontal and 23 cm in vertical component.