隨著新技術與應用的提出，現行通訊系統所使用的頻譜逐漸無法滿足人們對於資料傳輸速率的需求。因此，毫米波頻段大量未使用的頻寬使毫米波通訊成為下一世代通訊系統的潛力新星。同時，利用毫米波訊號短波長的特性，大型天線陣列搭配預編碼技術可以用來克服訊號衰減嚴重的問題。考量到射頻電路的高硬體複雜度，傳統全數位的預編碼方式並不適用於毫米波多輸出多輸入通訊系統，於是混合射頻/基頻預編碼被提出以減少射頻電路的數量，並被視為是毫米波通訊的關鍵技術之一。
本研究利用通道在時間上的連續性，提出一個基於粒子濾波器的波束追蹤演算法幫助解決在混合預編碼架構中的基底選擇問題。相比於現有文獻，我們藉由修改後的混合粒子濾波器放大機率分布中弱小的成分，搭配類似於多輸入多輸出系統中連續干擾消除偵測器概念的估計產生方式，省略了在基底選擇部分所需要的矩陣運算。此外，我們使用了簡化的重取樣演算法以提升運算平行度，並且修改使其適用於混合粒子濾波器的架構。在16x16一維線性天線陣列多輸入多輸出系統的毫米波通道環境中，模擬結果顯示本研究提出的演算法相比於現有文獻之演算法可以降低約40%的運算複雜度，並僅伴隨著些微的位元錯誤率損失，而在頻譜效率上則可以達到幾乎一樣的表現。

Transmission through the millimeter wave has been considered as one of the potential options for the next-generation wireless communication.
By exploiting the property of small wavelength of the millimeter wave signal,
the multiple-input multiple-output along with the precoding technology can be applied to overcome the critical problem of signal attenuation.
Moreover, the hybrid precoding architecture is included to reduce the hardware cost.
This study considers the correlation between temporally neighboring channels
and adopts the famous sequential Monte Carlo method known as particle filter to track the evolution of channels.
By including the modified mixture framework along with a novel output estimation method,
a beam-tracking algorithm is proposed to solve the basis selection problem in the hybrid precoding architecture.
Based on the commonly used extended S-V channel model,
the simulations under the 16x16 mmWave MIMO system indicates that the proposed algorithm can reduce the computational complexity
with negligible performance loss comparing to previous works.

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