無線定位是個重要且引人關注的議題，具有廣泛的市場應用需求，舉凡緊急救援和智慧運輸系統等皆需可靠的定位服務，而地面無線定位之主要誤差來源為因非通視傳播產生的量測誤差，其會大幅降低定位之性能，台灣地區地勢起伏相當大之地形特性更加劇此效應。
本論文提出一混合式定位技術，適用於通視環境以及非通視環境。本定位技術架構主要分成三個部分，首先取得訊號到達時間和到達角度兩位置相關量測量，基於此兩量測量利用線性化最小平方法計算得接收裝置候選的位置，接著在不需事先得到非通視誤差資訊之情況下，使用改良式殘差演算法於辨別各基地台為通視的或非通視的，最後，若環境中沒有非通視的基地台存在，直接視候選的接收裝置位置為所需的位置解，反之若有非通視的基地台存在，則使用有限制條件之最佳化方法抑制非通視誤差對定位之影響並計算接收裝置之最佳位置解。特別的是，本定位技術架構之三部分皆藉由數值地形模型之輔助以增進三維定位之準確性。
本論文進行一系列之電波傳遞模擬以取得訊號到達時間及到達角度兩量測量於定位計算，藉由於不同環境之模擬，驗證本定位技術於通視環境和非通視環境之定位性能。

The issue of positioning in wireless networks has drawn tremendous attention and gained intense interest. Wireless positioning technology facilitates a variety of location-based applications and services. The performance of ground-based wireless positioning systems is limited by errors primarily caused by the effect of non-line-of-sight (NLOS) propagation. Especially in Taiwan, the complex terrain characteristic aggravates this phenomenon. In this thesis, a novel hybrid positioning technique suitable for both line-of-sight (LOS) and NLOS environments is proposed. The proposed position determination scheme is mainly composed of three steps. The first is to obtain angle of arrival and time of arrival measurements. A linearization-based least squares method is successively employed to compute the candidate mobile station (MS) position based on these position-related measurements. Then, an improved residual algorithm is applied to distinguish between LOS and NLOS base stations (BSs) without requiring a priori information of NLOS error statistics. Finally, the candidate MS position estimated in the first step is regarded as the desired MS position in the absence of NLOS BS. Otherwise, a constrained optimization approach is utilized to mitigate NLOS errors and to optimally estimate the MS position. A significant characteristic of the proposed method is the use of digital terrain model to enhance the three-dimensional (3D) position determination process. Through simulations in different scenarios, it is demonstrated that the proposed positioning technique gives satisfactory 3D positioning performance in both LOS and NLOS propagation conditions.

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