為了對抗毫米波通訊中的嚴重傳播損耗，採用波束成形技術的巨量多重輸入多重輸出系統已被廣泛研究。為了解決傳統波束調準程序過於費時的問題，本篇論文提出了一種波束調準的方法使用以BCH碼為基礎的波束樣式。利用BCH碼能偵測及更正訊息錯誤的特性，將其應用至基地台端的波束樣式設計之中以傳送同步訊號。在用戶設備端，為了以各個接收波束所接收到的訊號找出所需的最佳波束組別，本篇論文也提出了利用BCH碼特性的兩種候選者挑選方式以及兩種最佳波束判定方式。
整體可歸納為以下程序：基地台端依序以多組經過BCH碼設計的多峰波束樣式廣播出數個同步訊號；用戶設備端依序以自身的多個波束各別掃描數個同步訊號；各個接收波束所接收到的訊號在經過一連串的候選者挑選及最佳波束判定步驟後，可用以決定出最佳的波束組別之索引；之後，用戶設備端回傳在接下來進行資料傳輸時所需的基地台波束索引，並完成波束調準的程序。

In order to conquer the severe propagation loss of the millimeter-wave (mmWave) communication, the massive multiple-input multiple-output (MIMO) systems adopting beamforming techniques have been widely studied. For solving the issue that the conventional beam alignment (BA) process is too time-consuming, a BA scheme utilizing the BCH-code-based beam patterns is proposed in this thesis. With the BCH code featuring the detection and correction of the message error, it is implemented to the design of beam patterns at the base station (BS) for the transmission of synchronization signals. At the user equipment (UE), to find the desired optimal beam-pairs with the received signals of each reception beam, two candidate selection methods as well as two optimal beam decision methods using the features of the BCH code are also proposed in this thesis.
The overall processes are summarized as below: a BS sequentially broadcasts the synchronization signals with the multi-modal beam patterns designed by the BCH code; a UE sequentially scans the synchronization signals with each of its beams; with the received signals of each reception beam undergoing a series of candidate selection and optimal beam decision procedures, the indexes of the optimal beam-pairs can then be determined; afterwards, the UE sends back the desired beam indexes of the BS for the upcoming data transmission, and finishes the BA process.

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