無線通訊技術為了提高傳輸效率，採用上行鏈路和下行鏈路的技術，其中上行鏈路會將用戶端設備得到的通道狀態資訊回傳給基地台，讓基地台可以依據目前的通道狀態更改之後的傳輸方式，達成提高傳輸效率的目的。然而，傳統的通道估測方法只能估測出訊號上的通道總影響，因此必須將大量的估測通道值回傳給基地台才能讓基地台得知現在的通道狀態，這樣勢必會造成龐大的通道狀態資訊回傳量。因此，本論文為了減少通道狀態資訊回傳量提出一種解決辦法，我們用牛頓正交匹配追蹤法估測出下行鏈路通道中的每一條路徑的增益和延遲，如此一來我們只需要回傳這些少量的細部資訊回基地台，即可在基地台重建下行鏈路之通道。

我們也將牛頓正交匹配追蹤法用於載波聚合的技術上，但不同頻帶的通道增益並不相同，因此我們先從其中一個頻帶 (在本論文定義為帶內) 估測細部資訊，再讓其他頻帶 (在本論文定義為帶外) 利用帶內估測出的通道延遲作最小平方法重新估測出帶外的通道增益，藉由此以上方法，我們除了可以減少通道狀態資訊的回傳，也可以減少帶外的導頻訊號使用量，本論文的最後也會用實際空口測試來作演算法效能的驗證。

In order to improve the transmission efficiency, wireless communication adopts uplink and downlink technologies. Through uplink, the user equipment (UE) feedbacks channel state information (CSI) to the base station (BS), then BS can change the transmission mode according to current CSI and achieve better transmission efficiency. However, the traditional channel estimation method can only estimate the total channel impact on each signal. Therefore, UE needs to feedback huge amount of CSI. In order to reduce the feedback of CSI, this paper proposes a new channel estimation method. This method uses newtonized orthogonal matching pursuit (NOMP) to estimates the gains and delays of the downlink channel, so we only need to feedback small amount of detail information of the channel to BS, then we can reconstruct the downlink channel in BS.

We also want to use this method for carrier aggregation technology. However, the channel gains of different frequency bands are not the same. Therefore, we first estimate the detail information from one of the frequency bands (which we define inband in this paper), then use least square (LS) to re-estimate the channel gain of other frequency bands (which we define out-of-band in this paper). By this method, we can not only reduce CSI, but also reduce pilot signals of out-of-band. At the end of this paper, we use over-the-air test to validate the performance of the algorithm.

論文審定書 i
誌謝 ii
摘要 iii
Abstract iv
目錄 v
圖次 vii
表次 ix
第一章 緒論 1
1.1引言與動機 1
1.2論文安排 4
第二章 LTE系統與相關演算法介紹 5
2.1 LTE訊框架構 5
2.2正交分頻多工簡介 6
2.3 LTE 資源架構 7
2.4多輸入多輸出技術 8
2.5相關演算法介紹 9
2.5.1訊號同步搜索 10
2.5.2通道估測 11
第三章 軟硬體整合開發 22
3.1 硬體架構 22
3.1.1傳送端 22
3.1.2接收端 22
3.2 軟體架構 25
3.2.1 用戶封包協定 25
3.2.2 多執行緒架構 27
3.3 開發問題與解決辦法 29
第四章 牛頓正交匹配追蹤 31
4.1 牛頓正交匹配追蹤 31
4.2 牛頓正交匹配追蹤應用於LTE系統 35
4.2.1 NOMP 用於LTE SISO系統 36
4.2.2 LTE SIMO系統 38
4.2.3 LTE SISO 系統用於載波聚合之估測 40
第五章 演算法模擬及空口測試 43
5.1 SIMO 帶內帶外通道重建之OTA測量 44
5.2 SISO 兩種頻帶通道重建之OTA測量 46
第六章 結論 49
參考文獻 50

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