發(fā)布時(shí)間：2018-10-20 20:16

【摘要】：當(dāng)今社會(huì)隨著移動(dòng)數(shù)據(jù)流量爆炸性增長(zhǎng)以及頻譜資源的短缺,大規(guī)模多輸入多輸出(MIMO)技術(shù)可以預(yù)見成為下一代移動(dòng)通信系統(tǒng)的核心技術(shù)點(diǎn),同時(shí)綠色通信也成為未來通信領(lǐng)域的焦點(diǎn)。本文主要研究大規(guī)模MIMO系統(tǒng)中的能效(EE)問題,具體研究?jī)?nèi)容如下:研究了基于Rayleigh信道分別在多小區(qū)和單小區(qū)情形下如何選擇基站天線數(shù)目和發(fā)送功率,以最大化多用戶大規(guī)模MIMO系統(tǒng)中的下行能效。與大多數(shù)以前的工作不同,我們使用更加實(shí)際的功耗模型,明確描述能效如何非線性地依賴于基站天線數(shù)目,終端用戶數(shù)和發(fā)送功率,在具有完美信道狀態(tài)信息(CSI)的迫零法(ZF)處理下導(dǎo)出用于最大化能效的參數(shù)解及其簡(jiǎn)單閉合表達(dá)式,最后通過數(shù)值分析得出了對(duì)應(yīng)各參數(shù)的最優(yōu)解,同時(shí)也證明了理論分析的正確性。我們對(duì)比了多小區(qū)和單小區(qū)這兩種情形在某些相同條件下的結(jié)果,而且在單小區(qū)情形中,同時(shí)還比較了在ZF、最小均方誤差(MMSE)和最大比傳輸/合并(MRT/MRC)這三種線性處理情形下系統(tǒng)能效與基站天線數(shù)的關(guān)系。研究了基于Nakagami衰落信道下大規(guī)模MIMO系統(tǒng)的下行能效,考慮了收發(fā)兩端CSI均已知和發(fā)送端CSI未知僅接收端CSI已知這兩種情形,并且分別利用了ZF和MMSE兩種線性處理法進(jìn)行分析對(duì)比。首先得到該系統(tǒng)的系統(tǒng)模型,該模型包括信道模型、一種新的電路功耗模型以及基于Nakagami信道的信號(hào)模型,然后基于這個(gè)系統(tǒng)模型得到系統(tǒng)能效的表達(dá)式,基于這個(gè)表達(dá)式我們可以分析能效的最優(yōu)解,最后通過數(shù)值分析加以驗(yàn)證。研究了與前兩章不同的小區(qū)結(jié)構(gòu)下的分布式天線系統(tǒng)能效,并與基于該小區(qū)結(jié)構(gòu)的集中式能效進(jìn)行了對(duì)比。首先根據(jù)發(fā)送端和接收端天線數(shù)量的不同配置,在一種雙重衰落信道下,得到分布式天線系統(tǒng)的能效近似表達(dá)式,并推導(dǎo)了各情況下的使能效最大的各參數(shù)的最優(yōu)解的表達(dá)式,如最優(yōu)的發(fā)送功率、基站天線數(shù)等。本章還基于Nakagami衰落信道研究了分布式大規(guī)模MIMO系統(tǒng)的能效。然后我們通過數(shù)值分析比較了各個(gè)情形下分布式和集中式的能效性能,以及分布式Nakagami信道下的能效,驗(yàn)證了兩種情況下理論分析的準(zhǔn)確性。最后聯(lián)系現(xiàn)實(shí),我們考慮到日�；炯茉O(shè)中下行通信中接收端(用戶設(shè)備)天線數(shù)一般不會(huì)超過發(fā)送端(基站)天線數(shù),因此可以得出分布式天線的能效一般來說比集中式天線更加突出,從而說明了分布式天線系統(tǒng)對(duì)于當(dāng)今的研究熱點(diǎn)綠色通信技術(shù)具有重要的研究意義。
[Abstract]:Nowadays, with the explosive growth of mobile data flow and the shortage of spectrum resources, the large-scale multi-input and multi-output (MIMO) technology can be predicted to become the core technology of the next generation mobile communication system. At the same time, green communication also becomes the focus of future communication field. In this paper, the problem of energy-efficient (EE) in large-scale MIMO systems is studied. The main contents are as follows: how to select the number of base station antennas and transmission power in multi-cell and single-cell cases based on Rayleigh channel is studied. In order to maximize the downlink energy efficiency in multi-user large-scale MIMO systems. Unlike most previous work, we use a more practical power model to explicitly describe how energy efficiency is nonlinear dependent on the number of base station antennas, the number of end users, and transmission power. The parameter solution and its simple closed expression for maximizing energy efficiency are derived under the Zero-forcing (ZF) process with perfect channel state information (CSI). Finally, the optimal solution for each parameter is obtained by numerical analysis. At the same time, it also proves the correctness of the theoretical analysis. We compare the results of multi-cell and single-cell under some same conditions, and in the case of single cell, The relationship between system energy efficiency and the number of base station antennas in the case of ZF, minimum mean square error (MMSE) and maximum ratio transmission / combination (MRT/MRC) is also compared. The downlink energy efficiency of large scale MIMO systems based on Nakagami fading channel is studied. Two cases are considered in which the CSI is known at both ends of the transmitter and receiver and only the CSI at the receiver is unknown at the sender and transmitter. Two linear processing methods, ZF and MMSE, are used to analyze and compare. First, the system model of the system is obtained, which includes the channel model, a new circuit power model and the signal model based on Nakagami channel, and then the expression of system energy efficiency is obtained based on the system model. Based on this expression, we can analyze the optimal solution of energy efficiency and verify it by numerical analysis. The energy efficiency of distributed antenna system under different cell structure from the previous two chapters is studied and compared with the centralized energy efficiency based on the cell structure. Firstly, according to the different configurations of antennas at the transmitter and receiver, the approximate expression of the energy efficiency of distributed antenna system is obtained in a dual fading channel, and the optimal solution of the parameters that make the maximum energy efficiency in each case is derived. Such as the optimal transmission power, base station antenna number and so on. This chapter also studies the energy efficiency of distributed large-scale MIMO systems based on Nakagami fading channels. Then we compare the distributed and centralized energy efficiency performance in each case and the energy efficiency in distributed Nakagami channel by numerical analysis, and verify the accuracy of the theoretical analysis in both cases. Finally, in connection with the reality, we consider that the number of receiving (user equipment) antennas in the downlink communication during the daily base station erection generally does not exceed the number of transmitting (base station) antennas. Therefore, it can be concluded that the energy efficiency of distributed antenna is generally more prominent than that of centralized antenna, which shows that distributed antenna system is of great significance to the research of green communication technology.
【學(xué)位授予單位】：南京郵電大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TN919.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 范建存;寧悅;鄧建國(guó);徐志昆;;多小區(qū)MIMO系統(tǒng)中基于能效最大的天線數(shù)和用戶數(shù)聯(lián)合優(yōu)化方案[J];中國(guó)科學(xué):信息科學(xué);2016年02期

相關(guān)碩士學(xué)位論文 前1條

1 陳明燕;基于Nakagami衰落的MIMO無線信道天線選擇研究[D];吉林大學(xué);2011年

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本文編號(hào)：2284280