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  本文選題：分布式天線系統(tǒng)　切入點：協(xié)作通信　出處：《南京郵電大學》2017年碩士論文　論文類型：學位論文

【摘要】：為了滿足人們?nèi)粘o線多媒體通信業(yè)務(wù)不斷增加的需要,下一代無線通信系統(tǒng)急需提供更高的傳輸速率和更可靠的傳輸性能。未來無線通信網(wǎng)絡(luò)必將是一個異構(gòu)通信網(wǎng)絡(luò),支持多種無線網(wǎng)絡(luò)的融合。與傳統(tǒng)蜂窩小區(qū)相比,在分布式天線系統(tǒng)中引入?yún)f(xié)作傳輸,不僅可以獲得多徑傳輸和多天線的性能增益,而且可以有效降低移動終端的發(fā)射功率和阻塞概率,顯著提升無線網(wǎng)絡(luò)的綜合傳輸性能,這方面的研究正受到越來越多的關(guān)注。論文主要研究了協(xié)作通信中節(jié)點的聯(lián)合發(fā)射功率分配問題和基于分布式天線系統(tǒng)的多用戶傳輸策略問題。首先,從協(xié)作中繼基本原理的角度出發(fā),詳細介紹采用兩種基本中繼轉(zhuǎn)發(fā)協(xié)議的幾種協(xié)作通信系統(tǒng)模型。不管是固定中繼的協(xié)作通信(協(xié)作MIMO)還是用戶終端間的協(xié)作通信(多用戶協(xié)作),它們的協(xié)作通信模型本質(zhì)上都是相同的。因為在無線通信系統(tǒng)中,各個天線節(jié)點和用戶終端都可以作為潛在的中繼節(jié)點,所以這里只考慮怎樣合理分配功率以滿足某一個或幾個有效的系統(tǒng)性能指標。接著,論文從能耗和性能的問題考慮,分別給出了基于單用戶傳輸信息的單中繼和多中繼的功率分配方法。采用直接計算法分析單中繼系統(tǒng),利用拉格朗日乘子算出最優(yōu)分配解;對多中繼系統(tǒng),利用拉格朗日乘子并結(jié)合最陡下降法給出最優(yōu)分配解的集合。而后分別對單中繼、多中繼系統(tǒng)的等功率分配和最優(yōu)功率分配進行仿真,并通過仿真結(jié)果驗證了協(xié)作傳輸能夠有效地改善了系統(tǒng)性能。最后,對基于分布式天線系統(tǒng)的協(xié)作通信進行研究。在分布式天線網(wǎng)絡(luò)中,依靠分布式天線進行通信,可以有效減小網(wǎng)絡(luò)覆蓋盲區(qū)以及顯著提高小區(qū)邊緣用戶的傳輸速率。但當小區(qū)用戶通信活躍時,顯然分布式天線不能滿足大多數(shù)用戶的通信需求,而且由于用戶都有通信需求,多用戶協(xié)作就很難開展。因此,論文介紹了一種基于談判能力的自組織組隊協(xié)作傳輸策略,仿真結(jié)果表明,對于相距較近的兩用戶,組隊協(xié)作可以使雙方獲得即時的性能增益。
[Abstract]:In order to meet the daily increasing demand of wireless multimedia communication services, the next generation wireless communication system urgently needs to provide higher transmission rate and more reliable transmission performance. In the future, wireless communication network will be a heterogeneous communication network. Compared with traditional cellular cell, cooperative transmission is introduced in distributed antenna system, which can not only achieve multi-path transmission and multi-antenna performance gain, but also support multi-wireless network fusion. Moreover, it can effectively reduce the transmission power and blocking probability of the mobile terminal, and significantly improve the comprehensive transmission performance of the wireless network. In this paper, the joint transmit power allocation of nodes and the multi-user transmission strategy based on distributed antenna system are studied. From the point of view of the basic principle of cooperative relay, Several kinds of cooperative communication system models using two basic relay forwarding protocols are introduced in detail. Whether they are fixed relay cooperative communication (cooperative MIMOO) or cooperative communication between user terminals (multi-user cooperative communication), their cooperative communication is introduced in detail. The models are essentially the same because in wireless communication systems, Each antenna node and user terminal can be used as potential relay nodes, so we only consider how to allocate power reasonably to satisfy one or more effective system performance indicators. The power allocation methods of single relay and multi relay based on single user transmission information are given respectively. The direct calculation method is used to analyze the single relay system, and the Lagrange multiplier is used to calculate the optimal allocation solution. The set of optimal allocation solutions is given by Lagrange multiplier and steepest descent method. Then the equal-power allocation and optimal power allocation of single-relay and multi-relay systems are simulated respectively. The simulation results show that cooperative transmission can effectively improve the performance of the system. Finally, the cooperative communication based on distributed antenna system is studied. It can effectively reduce the blind area of the network and significantly improve the transmission rate of the cell edge users. But when the cell users communicate actively, it is obvious that the distributed antenna can not meet the communication needs of most users, and because the users have communication needs, Therefore, a self-organizing cooperative transmission strategy based on negotiation ability is introduced in this paper. The simulation results show that for the two users who are close to each other, the team collaboration can achieve real-time performance gains.
【學位授予單位】：南京郵電大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TN92

【參考文獻】

相關(guān)碩士學位論文 前1條

1 李文佳;基于協(xié)作通信的功率分配算法研究[D];哈爾濱工業(yè)大學;2014年

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本文編號：1586067