本論文探討多相關器降低多路徑效應於GNSS所產生的量測誤差。GNSS為一發展成熟的系統，但仍有許多的外在因素影響其定位的精準性，例如：受電離層、對流層影響傳送速度以及接收器時鐘漂移等均構成誤差的來源。本文針對多路徑效應產生的定位誤差，提供一個利用多相關器的概念來降低誤差的產生，且對於以往文獻中降低多路徑影響的各種方法提供模擬並比較。另外本論文也描述新型導航訊號和目前GPS上訊號在多路徑效應上所呈現的差異性。

　The thesis is concerned with the use of multicorrelator technique in reducing multipath effect in GNSS application. Although GNSS has been widely used in navigation and survey, its performance is subject to several errors such as ionosphere delay, troposphere delay and multipath. Among which, the multipath effect constitutes one of the most unpredictable error sources. The multicorrelator techniques is analyzed in the thesis to assess its effectiveness in multipath mitigation. Both BPSK and BOC modulations are considered.

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