GPS為結合衛星與通訊技術的定位與導航之系統，此系統可提供在地球上任何無遮蔽物地點精準之定位與時間。一般GPS接收器之構成要素可包括為射頻前端、基頻帶訊號處理、定位計算，本論文將針對基頻帶訊號處理做探討，並以射頻前端接收訊號做軟體模擬，透過DSP韌體驗證法則與效能，最後以FPGA實現可即時處理之相關器模組。此外，本論文將探討常見於民用GPS接收器的定位誤差來源－多路徑效應，並透過相關器設計改善時延迴路架構，降低多路徑效應所帶來的電碼追蹤誤差。

GPS is a satellite-based navigation and positioning system that is capable of providing an accurate position and time to users on earth. A GPS receiver contains RF front-end, baseband signal processing, and navigation data computation. This thesis investigates the GPS baseband signal processing, simulates the signal processing algorithms, verifies the performance through DSP firmware, and ,finally, implements the real-time correlator module using FPGA (Field Programmable Gate Array). Besides, this thesis investigates the multipath effect which is a common error source in civilian GPS receiver. Mitigation techniques for the multipath effects are analyzed using advanced correlator architectures.

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