【摘要】：多輸入多輸出技術(shù)廣泛應(yīng)用于無線通信系統(tǒng)中，對空時編碼和波束成形技術(shù)的研究表明，發(fā)射機利用先驗信道狀態(tài)信息，采用閉環(huán)MIMO中的波束成形技術(shù)或預(yù)編碼技術(shù)可以進一步提高系統(tǒng)的傳輸質(zhì)量，增加系統(tǒng)容量，這兩項MIMO技術(shù)已在第三代移動通信系統(tǒng)標準和長期演進技術(shù)標準中得到了應(yīng)用。 本文圍繞LTE及其后續(xù)演進系統(tǒng)中波束成形技術(shù)，根據(jù)信道的互易性，主要研究了波束成形技術(shù)的基本理論、典型的波束成形算法、接收端的檢測算法和波束成形技術(shù)在LTE中的應(yīng)用，然后在飛思卡爾DSP硬件平臺上實現(xiàn)了典型的波束成形技術(shù)-基于SVD分解的波束成形算法，最后對DSP實現(xiàn)性能進行了分析，，。 本文首先概述了無線通信的發(fā)展、LTE-TDD演進路線、概述了LTE-TDD系統(tǒng)的關(guān)鍵技術(shù)、介紹了LTE-TDD的物理層，并對LTE-TDD下行共享信道的處理流程進行了介紹。 其次介紹了MIMO-OFDM系統(tǒng)中波束成形技術(shù)的基本理論。首先分析了多天線系統(tǒng)、空時分組編碼和波束成形系統(tǒng)的系統(tǒng)容量，突出了波束成形在系統(tǒng)容量上的優(yōu)勢。然后介紹了常用的波束成形技術(shù)算法：奇異值分解算法、幾何均值分解算法、信道反轉(zhuǎn)算法，并介紹了波束成形技術(shù)的復(fù)用方式、有限反饋下的波束成形技術(shù)和多用戶波束成形技術(shù)。最后介紹了波束成形檢測算法，主要有：迫零算法、最小均方誤差算法、連續(xù)干擾消除算法和最大似然算法。并在簡化的LTE-TDD下行共享信道下，通過仿真驗證上述波束成形算法和檢測算法，通過分析確定了適于DSP實現(xiàn)的波束成形算法和檢測算法。 最后介紹了波束成形技術(shù)的DSP的實現(xiàn)。首先介紹了飛思卡爾DSP開發(fā)平臺-MSC8156ADS，然后介紹了DSP實現(xiàn)的主要軟件流程和主要實現(xiàn)函數(shù)。最后通過對DSP實現(xiàn)的波束成形技術(shù)進行的系統(tǒng)測試，結(jié)果表明DSP實現(xiàn)比MATLAB仿真大約損失2dB；并以代碼執(zhí)行效率和執(zhí)行時間為指標對DSP的主要模塊進行了評估，結(jié)果表明，代碼執(zhí)行時間為0.8928ms小于1ms，達到LTE系統(tǒng)所需的時延要求。 論文的最后一章總結(jié)了前面的研究工作并且指出了下一步可能的研究方向。
[Abstract]:Multi-input and multi-output technology is widely used in wireless communication systems. The research on space-time coding and beamforming shows that the transmitter uses prior channel state information. The beamforming or precoding technology in closed-loop MIMO can further improve the transmission quality and increase the system capacity. These two MIMO technologies have been applied in the third generation mobile communication system standards and the long-term evolution technology standards. This paper focuses on the beamforming technology in LTE and its subsequent evolution system. According to the reciprocity of channel, the basic theory of beamforming technology and typical beamforming algorithm are studied in this paper. The detection algorithm and beamforming technology of the receiver are applied in LTE. Then the typical beamforming technology based on SVD decomposition is implemented on the Freescale DSP hardware platform. Finally, the performance of DSP implementation is analyzed. In this paper, the evolution of LTE-TDD, the key technology of LTE-TDD system, the physical layer of LTE-TDD, and the processing flow of LTE-TDD downlink shared channel are introduced. Secondly, the basic theory of beamforming technology in MIMO-OFDM system is introduced. Firstly, the system capacity of multi-antenna system, space-time block coding and beamforming system is analyzed, which highlights the advantages of beamforming in system capacity. Then it introduces the commonly used beamforming algorithms: singular value decomposition algorithm, geometric mean decomposition algorithm, channel inversion algorithm, and introduces the multiplexing method of beamforming technology. Beamforming technology and multi-user beamforming technology under finite feedback. Finally, the beamforming detection algorithms are introduced, including zero forcing algorithm, minimum mean square error algorithm, continuous interference cancellation algorithm and maximum likelihood algorithm. Under the simplified LTE-TDD downlink shared channel, the beamforming algorithm and detection algorithm are verified by simulation, and the beamforming algorithm and detection algorithm suitable for DSP implementation are determined by analyzing and determining the beamforming algorithm and detection algorithm. Finally, the DSP implementation of beamforming technology is introduced. This paper first introduces Freescale DSP development platform-MSC8156ADS. then introduces the main software flow and main realization functions of DSP. Finally, through the system test of beamforming technology implemented by DSP, the results show that the DSP implementation is about 2 dB less than MATLAB simulation, and the main modules of DSP are evaluated with the index of code execution efficiency and execution time, and the results show that, The code execution time is less than 1 Ms for 0.8928ms, which meets the delay requirement of LTE system. The last chapter summarizes the previous research work and points out the possible future research direction.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2012
【分類號】：TN929.5;TP368.1

【參考文獻】

相關(guān)碩士學(xué)位論文 前4條

1 周智勛;基于信道互易性的波束成形算法研究[D];電子科技大學(xué);2011年

2 王階;MIMO系統(tǒng)中信道估計技術(shù)研究[D];電子科技大學(xué);2005年

3 劉寧;MIMO-OFDM系統(tǒng)下波束成形技術(shù)研究[D];電子科技大學(xué);2008年

4 頓玉成;空間信道建模仿真研究[D];西安電子科技大學(xué);2008年

本文編號：2171577