現行的通信系統所使用的頻段都集中在6 GHz 以下，然而隨著高速通信需求不斷地提高，6 GHz 頻段將越加壅擠。因此，具有龐大頻譜潛力的毫米波頻段通訊系統，被視為下個世代的主力服務頻段。然而，毫米波的頻段相對於低頻段有更嚴重的路徑能量損耗，因此需要波束賦形的技術來實現長距離的通訊。波束賦形技術通常是利用多根天線形成的天線陣列來達成某個特定方向的指向性傳輸，然而在傳收兩端的使用波束會有匹配的問題，尤其在用戶端移動的場景下，傳收兩端的波束匹配更需要不斷的更新。在本篇論文中，我們先回顧了幾種波束匹配的演算法，並提出了以利用毫米波頻帶外的訊號衍生特性，做為輔助毫米波波束匹配的演算法。我們也提出了兩階段式的波束掃描演算法來增加通訊系統一開始在傳收兩端完成波束匹配的效率。最後我們提出主動式的調整調變與編碼策略，而使資料的傳輸能根據通道的狀態來自動調整。這些提出的方法皆實做在以軟體定義無線電為基礎的平台，並在室內大廳進行現場測量。根據實驗的結果，我們比較了現有方法跟提出的方法，並歸納出優缺點及效能分析。

As the demand of high speed wireless communication rises fiercely, the higher frequency band with tremendous available spectrum is a strong candidate to meet the need of future wireless communications. Among all the high frequency bands, the millimeter-wave (mmWave) frequency band has attracted much attention from both industry and academia. However, the high path loss on mmWave frequency band can greatly attenuate the signal strength. To overcome this issue, beamforming techniques with array antennas are usually considered for mmWave communications. Nevertheless, under the moving scenario, the beam alignment needs to be updated whenever the beam pair strength is not strong enough to maintain the communication link. In this thesis, a two-stage beam scanning method and a beam tracking method with the aid of out-of-band information are proposed to efficiently solve the beam misalignment problem. The proposed methods are implemented on an software-defined radio prototype system. To further enhance the data transmission rate, modulation and coding scheme adjustment algorithm is proposed to adapt the transmission rate to channel conditions. Through measurement results, the merits of the proposed methods are confirmed in comparison with the conventional method.

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