【摘要】：多輸入多輸出(MIMO)技術(shù)以其高復(fù)用增益和分集增益等優(yōu)勢,一直是無線通信和信號處理領(lǐng)域的研究重點(diǎn)。MIMO預(yù)編碼技術(shù)可以降低接收端檢測復(fù)雜度、減小誤碼率并提高系統(tǒng)容量。因此,對發(fā)射信號進(jìn)行預(yù)處理,是當(dāng)前MIMO系統(tǒng)的主流處理技術(shù)。空間調(diào)制是近年來提出的一種新穎的多天線傳輸技術(shù),被廣泛應(yīng)用于單用戶MIMO系統(tǒng),用于減少檢測的復(fù)雜度、消除符號間干擾。實際上,多用戶MIMO系統(tǒng)是未來通信技術(shù)的主流方向。研究表明,對多用戶MIMO空間調(diào)制系統(tǒng)在發(fā)射端進(jìn)行適當(dāng)?shù)念A(yù)處理,可以避免多用戶MIMO帶來的內(nèi)部信道干擾(ICI),消除用戶間干擾,并提高系統(tǒng)性能。論文主要針對多用戶MIMO空間調(diào)制系統(tǒng)的發(fā)射機(jī)預(yù)處理和功率分配問題進(jìn)行了研究,具體研究內(nèi)容如下： (1)：介紹了MIMO預(yù)編碼技術(shù),分析了單用戶MIMO和多用戶MIMO預(yù)編碼模型及幾種較為典型的預(yù)編碼方法,包括迫零預(yù)編碼、最小均方誤差預(yù)編碼、奇異值分解預(yù)編碼和塊對角化預(yù)編碼,并分析了各自的優(yōu)缺點(diǎn)。 (2)：研究了將發(fā)射機(jī)預(yù)編碼應(yīng)用于多用戶MIMO空間調(diào)制系統(tǒng)。首先通過塊對角化預(yù)編碼器,完全消除用戶間干擾,將多用戶MIMO變?yōu)槎鄠�具有平行信道的單用戶MIMO;其次,對每個獨(dú)立的單用戶MIMO系統(tǒng)進(jìn)行接收空間調(diào)制,通過接收天線序號和傳統(tǒng)幅度相位調(diào)制同時攜帶信號,有效地避免了天線間干擾,并減低接收端檢測復(fù)雜度。在多用戶MIMO空間調(diào)制預(yù)處理系統(tǒng)中,通過理論計算得出功率分配因子與系統(tǒng)誤碼率上邊界值的函數(shù)關(guān)系,使用梯度下降方法解出了各用戶的功率分配因子。將系統(tǒng)在該功率分配因子情形下與未進(jìn)行功率分配的情形下進(jìn)行誤碼率上邊界的對比。得出結(jié)論為系統(tǒng)經(jīng)功率分配后,誤碼率上邊界明顯降低。
[Abstract]:Because of its advantages of high multiplexing gain and diversity gain, multi-input and multi-output (MIMO) technology has been a research focus in the field of wireless communication and signal processing. MIMO-precoding technology can reduce the detection complexity, reduce the bit error rate and improve the system capacity. Therefore, preprocessing the transmitted signal is the mainstream processing technology of MIMO system at present. Spatial modulation is a novel multi-antenna transmission technology proposed in recent years. It is widely used in single-user MIMO systems to reduce the complexity of detection and to eliminate inter-symbol interference. In fact, multi-user MIMO system is the main direction of communication technology in the future. The research shows that the multi-user MIMO spatial modulation system can be pretreated properly at the transmitter, which can avoid the internal channel interference caused by the multi-user MIMO and eliminate the inter-user interference, and improve the performance of the system. This paper mainly focuses on the transmitter preprocessing and power allocation of multi-user MIMO spatial modulation system. The main contents are as follows: (1) the MIMO precoding technology is introduced. The precoding models of single user MIMO and multiuser MIMO and several typical precoding methods are analyzed, including zero forcing precoding, minimum mean square error precoding, singular value decomposition precoding and block diagonalization precoding. Their advantages and disadvantages are analyzed. (2) the application of transmitter precoding to multi-user MIMO spatial modulation system is studied. Firstly, the block diagonalization precoder is used to completely eliminate interuser interference and transform the multi-user MIMO into multiple single-user MIMOs with parallel channels. Secondly, each independent single-user MIMO system is modulated by receiving space. The received antenna sequence number and the traditional amplitude and phase modulation simultaneously carry the signal, which effectively avoids the inter-antenna interference and reduces the detection complexity of the receiver. In the multi-user MIMO spatial modulation preprocessing system, the function relationship between the power allocation factor and the boundary value on the bit error rate of the system is obtained by theoretical calculation, and the power allocation factor of each user is solved by using gradient descent method. The BER upper boundary is compared between the power allocation factor and the power allocation. It is concluded that the upper boundary of BER decreases obviously after power allocation.
【學(xué)位授予單位】：華中師范大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TN919.3

【參考文獻(xiàn)】

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1 郭明喜;賈沖;沈越泓;魏以民;侯興康;;空間調(diào)制技術(shù)及其性能仿真[J];軍事通信技術(shù);2009年03期

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本文編號：2144299