【摘要】：多輸入多輸出（Multiple-Input Multiple Output, MIMO）技術(shù)能夠利用多徑效應(yīng)，在不需要增加頻譜資源以及發(fā)送功率的情況下能大幅度提高系統(tǒng)信道容量，從而提高頻譜效率。MIMO技術(shù)正是具有這一優(yōu)勢(shì)，從而成為新一代無(wú)線通信系統(tǒng)的關(guān)鍵技術(shù)之一。然而，，當(dāng)MIMO技術(shù)運(yùn)用于多小區(qū)系統(tǒng)時(shí)，由于各小區(qū)的頻譜復(fù)用因子為1，所以處在小區(qū)邊緣的用戶就會(huì)因?yàn)檫h(yuǎn)離本小區(qū)基站而受到嚴(yán)重的相鄰小區(qū)同頻干擾，以至于邊緣用戶無(wú)法正常通信。小區(qū)間的同頻干擾嚴(yán)重地影響了整個(gè)系統(tǒng)的性能，系統(tǒng)成為一個(gè)干擾受限的系統(tǒng)。因此，抑制小區(qū)間的同頻干擾成為多小區(qū)MIMO系統(tǒng)十分重要的問(wèn)題。 本文首先論述了MIMO技術(shù)的研究背景、意義、國(guó)內(nèi)外研究現(xiàn)狀并介紹了MIMO系統(tǒng)的基本概念。接著討論了無(wú)線通信系統(tǒng)的信道模型，并闡述了單用戶MIMO系統(tǒng)、單小區(qū)多用戶MIMO系統(tǒng)以及多小區(qū)MIMO系統(tǒng)的信道模型，并給出了各系統(tǒng)信道模型下的接收信號(hào)表達(dá)式。利用MIMO技術(shù)能夠大幅度提高系統(tǒng)的頻譜利用率，因此本文也對(duì)MIMO系統(tǒng)的信道容量做了較詳細(xì)的討論，分析了不同系統(tǒng)信道的容量并對(duì)系統(tǒng)信道容量做了仿真比較。在討論MIMO系統(tǒng)中多小區(qū)間干擾抑制時(shí)，本文首先介紹了單用戶MIMO系統(tǒng)多種檢測(cè)技術(shù)以及單小區(qū)多用戶MIMO系統(tǒng)基于發(fā)送端預(yù)編碼技術(shù)，并對(duì)它們的性能做了仿真對(duì)比。然后過(guò)渡到多小區(qū)MIMO系統(tǒng)，對(duì)多小區(qū)MIMO系統(tǒng)干擾抑制的傳統(tǒng)方法做了研究，并對(duì)單小區(qū)模式下以及多小區(qū)聯(lián)合處理模式下的多區(qū)間干擾抑制方法做了對(duì)比，分析了二者的優(yōu)劣所在。由于單小區(qū)模式下系統(tǒng)的誤碼率性能較差，而多小區(qū)聯(lián)合處理模式系統(tǒng)復(fù)雜度較高，所以這兩種方法都不是很好的多小區(qū)干擾抑制方案。 文章重點(diǎn)研究了一種主動(dòng)式干擾抑制方法，該方法是從干擾生成的角度考慮，將本基站產(chǎn)生的干擾進(jìn)行主動(dòng)抑制，當(dāng)所有小區(qū)都采用主動(dòng)式干擾抑制方法時(shí)，整個(gè)系統(tǒng)性能得到最佳。與單小區(qū)模式相比，主動(dòng)式干擾抑制方法能夠大大提高系統(tǒng)的誤碼率性能，與傳統(tǒng)的多小區(qū)聯(lián)合迫零模式相比，主動(dòng)式干擾抑制方法具有較低的系統(tǒng)復(fù)雜度，且保持了系統(tǒng)的誤碼率性能。主動(dòng)式干擾抑制方法有兩種實(shí)現(xiàn)方案，一種是將干擾信道矩陣的所有子空間進(jìn)行迫零來(lái)消除基站產(chǎn)生的干擾，稱為主動(dòng)式迫零預(yù)編碼；另一種是將干擾信道矩陣最大奇異值所對(duì)應(yīng)的子信道進(jìn)行迫零，稱之為最大特征干擾子信道預(yù)編碼，與主動(dòng)式迫零預(yù)編碼相比，其提高了基站發(fā)送信息的天線自由度。如果不增加所要發(fā)送的有效信息數(shù)據(jù)流的數(shù)目，則基站發(fā)送天線數(shù)目大大減少。
[Abstract]:Multi-input-multiple-output (Multiple-Input Multiple Output, MIMO) technology can greatly improve the channel capacity without increasing spectrum resource and transmission power by using multipath effect. Therefore, it becomes one of the key technologies of the new generation wireless communication system. However, when the MIMO technology is applied to the multi-cell system, because the spectrum multiplexing factor of each cell is 1, the users on the edge of the cell will be seriously interfered by the same frequency of the adjacent cell because they are far from the base station of the cell. So that edge users can not communicate properly. The performance of the whole system is seriously affected by the co-frequency interference of the cell, and the system becomes an interference-limited system. Therefore, it is very important to suppress the co-frequency interference in multi-cell MIMO systems. This paper first discusses the research background and significance of MIMO technology, the current research situation at home and abroad, and introduces the basic concept of MIMO system. Then the channel model of wireless communication system is discussed, and the channel models of single-user MIMO system, single-cell multi-user MIMO system and multi-cell MIMO system are discussed, and the expressions of received signals under each system channel model are given. The spectral efficiency of the system can be greatly improved by using MIMO technology. Therefore, the channel capacity of MIMO system is discussed in detail, and the channel capacity of different systems is analyzed and compared by simulation. In the discussion of multi-cell interference suppression in MIMO system, this paper first introduces several detection techniques of single-user MIMO system and single-cell multi-user MIMO system based on sending-end precoding technology, and makes a simulation comparison of their performance. Then, the traditional methods of interference suppression in multi-cell MIMO system are studied, and the methods of multi-cell interference suppression in single-cell mode and multi-cell joint processing mode are compared. The advantages and disadvantages of the two are analyzed. Because the BER performance of the system in single-cell mode is poor and the complexity of multi-cell joint processing mode is high, neither of these two methods is a good multi-cell interference suppression scheme. In this paper, an active interference suppression method is studied. The method is to suppress the interference generated by the base station from the point of view of interference generation. When all the cells adopt the active interference suppression method, The performance of the whole system is optimized. Compared with single cell mode, active interference suppression method can greatly improve the BER performance of the system. Compared with the traditional multi-cell combined zero-forcing mode, the active interference suppression method has lower system complexity. The BER performance of the system is maintained. There are two schemes for active interference suppression. One is to eliminate the interference generated by the base station by forcing all subspaces of the interference channel matrix, which is called active zero-forcing precoding. The other is to force the subchannel corresponding to the maximum singular value of the interference channel matrix, which is called the maximum characteristic interference sub-channel precoding. Compared with the active zero-forcing precoding, it improves the antenna degree of freedom for the base station to transmit information. If the number of valid information streams to be transmitted is not increased, the number of transmit antennas in the base station is greatly reduced.
【學(xué)位授予單位】：重慶大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TN919.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 陳斌;胡宏林;張小東;卜智勇;;未來(lái)移動(dòng)通信系統(tǒng)中的小區(qū)間干擾協(xié)調(diào)技術(shù)[J];電信科學(xué);2006年06期

2 劉乃金;邱玲;朱近康;;多小區(qū)MIMO系統(tǒng)中的一種主動(dòng)式干擾抑制方案[J];數(shù)據(jù)采集與處理;2008年06期

相關(guān)博士學(xué)位論文 前1條

1 王階;MIMO系統(tǒng)中的定向干擾抑制研究[D];電子科技大學(xué);2010年

本文編號(hào)：2203166