本論文針對適應性陣列天線的於GPS干擾抑制和訊號增強性能進行分析與探討。GPS為一發展成熟之系統，但是由於其微弱信號使得其定位效能容易受外界干擾信號所影響，而適應性陣列天線是抗干擾技術中之一，其理論上效能是最佳的。本文針對各種不同波束合成法則作探討並加以修改，進而利用MATLAB模擬和分析適應性陣列天線干擾抑制的效能在不同的波束合成法則及不同的干擾信號(持續性弦波、頻率調變和虛擬衛星)的差異。最後我們實現一由四個天線所組成的陣列天線模組並且實際接收訊號及干擾，並將波束合成法則驗證於實際接收訊號上，達到增強GPS訊號強度及干擾抑制的效果。

　The GNSS signal is a weak signal and easily influenced by interferences. An antenna array with beamforming algorithm can be used to improve GNSS signal acquisition and interference mitigation performance. This thesis addresses interference mitigation and signal enhancement performance analysis by an adaptive antenna array. The presence of an antenna array allows the receiver to operate in spatial domain in addition to temporal (code) domain. Several beamforming algorithms are analyzed and a revised power minimization method is emphasized. We analyse interference mitigation performance of these techniques in the presence of different broadband and narrowband interferences (continuous wave, FM, and Pseudolite) through simulations. Analytic, numerical, and simulation comparisons illustrate the relative merits of the investigated adaptive beamforming algorithms. Finally, an array of four antenna elements placed in rectangular shape is implemented and tested with real GPS and interference signals. This architecture is built in PC-based environment. Field tests of adaptive antenna array confirm the applicability of the proposed method in interference and signal enhancement.

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