本文關(guān)鍵詞：LTE網(wǎng)絡(luò)自優(yōu)化方法研究　出處：《中國科學(xué)技術(shù)大學(xué)》2014年博士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 自組織網(wǎng)絡(luò) 長期演進系統(tǒng)(LTE) 移動負(fù)載均衡 干擾協(xié)調(diào) 能耗節(jié)省

【摘要】：為了降低下一代無線網(wǎng)絡(luò)中參數(shù)配置和管理的人工成本,進一步提高網(wǎng)絡(luò)的操作和維護性能,無線網(wǎng)絡(luò)應(yīng)該具有內(nèi)在的自組織特性：允許網(wǎng)絡(luò)中的各個節(jié)點去偵查它們的環(huán)境,協(xié)作形成它們的拓?fù)浣Y(jié)構(gòu)并可以管理自己的運行參數(shù)以及適應(yīng)周圍環(huán)境的變化。為了推進無線網(wǎng)絡(luò)自組織化的研究,下一代移動網(wǎng)絡(luò)組織(Next Generation Mobile Networks:NGMN)發(fā)布了自組織網(wǎng)絡(luò)(Self-Organizing Networks, SON)研究的白皮書,并認(rèn)為在長期演進網(wǎng)絡(luò)(Long Term Evolution:LTE)中,SON是降低成本和復(fù)雜度,以及提高網(wǎng)絡(luò)性能的最有效手段。另外,第三代合作伙伴計(3rd Generation Partnership Project:3GPP)也發(fā)布了關(guān)于LTE網(wǎng)絡(luò)自組織技術(shù)的構(gòu)架。網(wǎng)絡(luò)的自組織化過程總體可以分為三個組成部分：自配置過程,自優(yōu)化過程以及自恢復(fù)過程,分別對應(yīng)于網(wǎng)絡(luò)中各節(jié)點的加入,參數(shù)優(yōu)化以及錯誤恢復(fù)。由于自優(yōu)化作為連接自配置和自恢復(fù)兩個組成部分的中間紐帶,是整個網(wǎng)絡(luò)自組織化過程的核心,本文重點關(guān)注網(wǎng)絡(luò)自組織化中的自優(yōu)化問題。 本文基于3GPP發(fā)布的自組織技術(shù)框架,針對LTE網(wǎng)絡(luò)中的自優(yōu)化問題,從網(wǎng)絡(luò)的負(fù)載量出發(fā),研究并分析了網(wǎng)絡(luò)在不同的負(fù)載統(tǒng)計量下面對的三個主要自優(yōu)化用例并提出相應(yīng)的解決方案：中高等且大方差負(fù)載下的負(fù)載均衡自優(yōu)化用例,中高等且小方差負(fù)載下的干擾協(xié)調(diào)自優(yōu)化用例和低負(fù)載下的能耗節(jié)省自優(yōu)化用例。其中負(fù)載均衡自優(yōu)化用例,我們研究分析了如何根據(jù)現(xiàn)有的負(fù)載狀態(tài),各個基站或者用戶自適應(yīng)的調(diào)整用戶和基站的接入關(guān)系,使得各個基站的負(fù)載區(qū)域均衡,從而獲得更高的接入成功率和切換成功率；其中干擾協(xié)調(diào)自優(yōu)化用例中,我們研究了在標(biāo)準(zhǔn)軟頻率復(fù)用(SFR)的方案中,如何根據(jù)用戶業(yè)務(wù)的空間位置以及時間到達上的動態(tài)變化而自適應(yīng)的調(diào)節(jié)功率因子以提高系統(tǒng)吞吐量,以及如何根據(jù)用戶對于各個資源快的信道衰落不一致而自適應(yīng)的分配資源塊以降低資源塊使用量和提高接入用戶數(shù)；其中能耗節(jié)省自優(yōu)化用例,我們研究分析了如何用最少的基站來滿足現(xiàn)有系統(tǒng)的所有用戶,并分析了基站開關(guān)來實現(xiàn)能耗節(jié)省的機制。 對于負(fù)載均衡自優(yōu)化用例,我們分別從基站的角度以及用戶的角度出發(fā)分別進行了研究,并提出了不同的解決方案。從基站的角度出發(fā),由于3GPP3定義了"EVENT A3"為切換觸發(fā)條件,那么可以針對現(xiàn)在的系統(tǒng)負(fù)載狀況調(diào)整每個基站的切換觸發(fā)條件從而使得用戶更容易從高負(fù)載的小區(qū)切換到低負(fù)載的小區(qū),從而得到負(fù)載均衡�；诖�,我們提出了一種自適應(yīng)的小區(qū)互偏移量調(diào)整算法。從用戶的角度出發(fā),針對現(xiàn)在的系統(tǒng)負(fù)載狀況,各個用戶可以分布式的選擇接入基站和切換基站從而得到負(fù)載均衡,從而實現(xiàn)自適應(yīng)的接入?yún)^(qū)域和切換區(qū)域調(diào)整�；诖�,我們提出了一種分布式的基于負(fù)載效用的自適應(yīng)用戶接入和切換算法,并分析了該算法的最優(yōu)性,收斂性等。 對于基于軟頻率復(fù)用的干擾協(xié)調(diào)自優(yōu)化用例,我們提出了自適應(yīng)的分布式迭代更新SFR功率因子的算法,在每個功率因子更新時隙,各個小區(qū)探測各個資源塊上的干擾狀況,然后針對現(xiàn)有的用戶數(shù)目以及對應(yīng)的各個資源塊上的信道衰落情況,計算可以達到最大化系統(tǒng)吞吐量的功率因子,并根據(jù)上個時隙的功率因子各自獨立的自適應(yīng)調(diào)整當(dāng)前時刻的功率因子,從而保證各個小區(qū)在最大化系統(tǒng)吞吐量的同時,分布式而又自適應(yīng)的功率因子更新過程又是收斂的。與此同時,我們分析了在SFR框架下,對各個小區(qū)邊緣頻段進行動態(tài)分配可以得到的分集增益,并說明了隨著網(wǎng)絡(luò)規(guī)模的增大,該分集增益將逐漸降低,進而提出了應(yīng)該著重研究各個小區(qū)內(nèi)資源塊和用戶的分配,提出了最小化資源塊使用量和最大化用戶接入數(shù)的資源塊分配數(shù)學(xué)模型,并采用圖論中的最大獨立集理論加以解決。 對于基于基站開關(guān)的能耗節(jié)省自優(yōu)化用例,我們研究分析了“如何根據(jù)網(wǎng)絡(luò)現(xiàn)有的負(fù)載狀態(tài)和業(yè)務(wù)請求,自適應(yīng)的開啟或者關(guān)閉基站?”這個問題。構(gòu)建了最小能耗節(jié)省(MEC)的優(yōu)化模型并證明了MEC問題是個NP-Hard問題,然后我們提出了兩個具有多項式復(fù)雜度的算法從而滿足自組織解決方案的“可擴展性”特點。與此同時,我們討論了如何將這兩個算法應(yīng)用到網(wǎng)絡(luò)中。 本文的研究結(jié)果對LTE網(wǎng)絡(luò)中自組織技術(shù)方案的設(shè)計有一定的指導(dǎo)意義。
[Abstract]:In order to reduce the labor cost parameters in next generation wireless network configuration and management, further improve the network operation and maintenance performance, wireless network should have the characteristics of self-organization within: allows every node in the network to investigate their environment, collaboration form their topology and can manage and adapt to changes in their operating parameters the surrounding environment. In order to promote the research on the self organization of the wireless network, the mobile network organization next generation (Next Generation Mobile Networks:NGMN) released a self organizing network (Self-Organizing, Networks, SON) of the white paper, and that in the long term evolution network (Long Term Evolution:LTE), SON is to reduce the cost and complexity, and improve the most effective means of network performance. In addition, the third generation partnership project (3rd Generation Partnership Project:3GPP) also released on the LTE network Framework technology. Network self-organization process generally can be divided into three parts: self configuration process, self optimization, self recovery process, adding respectively corresponding to each node in the network, parameters optimization and error recovery. Due to the self optimization as connected self configuration and self recovery of the two components the intermediate link, is the core of the process of network self organization, self optimization problem this paper focuses on the self organization in the network.
The self organization technology framework based on the issue of 3GPP, aiming at the self optimization problem in LTE network, starting from the load of the network, research and analysis of network load in statistics facing three major self optimization case and puts forward the corresponding solutions different: the higher and larger variance of load balancing under self optimization in the case of higher and small variance under load interference coordination self optimization case and low load of energy saving optimization cases. The load balancing optimization case, we analyzed how to according to the load condition of the existing relationship between users and base station access, adjust the base station or user adaptive, the load balance of every region the base station, so as to obtain the success rate of access and the higher handover success rate; the self interference coordination optimization case, we study the soft frequency reuse in the standard (SFR). In the case, according to the dynamic change of the reach user service location and time adaptive power factor and to improve the system throughput, and according to the users for fast fading channel of each resource is inconsistent and the allocation of resources to reduce the block adaptive resource block volume and increase the number of users; the energy saving self optimization case, we study and analyze how to use the least base station to meet the needs of all users of the existing system, and analyzes the mechanism of base station switch to achieve energy saving.
For the load balancing optimization case, we were from the base station and the angle of the user's point of view was studied respectively, and puts forward different solutions. Starting from the base point of view, the definition of "3GPP3 EVENT A3" trigger conditions for the switch, you can switch to current system load condition adjustment of each base station trigger conditions so as to make it easier for users to switch from the small high load to low load cell, so as to obtain load balance. Based on this, we propose an adaptive neighborhood mutual offset adjustment algorithm. From the user's point of view, the current system load conditions, each user can choose the distributed base station and base station access switch in order to get the load balance, so as to realize the access region and the adjustment of the adaptive switching region. Based on this, we propose a distributed load based on Utility The adaptive user access and handover algorithm is used, and the optimality and convergence of the algorithm are analyzed.
For the case of self optimization interference coordination based on soft frequency reuse, we propose a distributed iterative adaptive update algorithm to update the SFR power factor, power factor in each time slot, each cell of each resource block interference detection, and then according to the number of users and each resource block corresponding to the channel fading, power factor calculation can maximize system throughput, and according to the power factor adjustment of power factor on the adaptive time slot of the independent current at the same time, so as to ensure the maximum system throughput of each cell, power factor and adaptive distributed update process is convergent. At the same time, we analyzed under the framework of SFR that was the diversity gain can be dynamically allocated to each cell edge band, and explained with the network size increases, the Set the gain will be reduced gradually, and then put forward the distribution of each cell in the study should focus on resource blocks and users, the resource block allocation mathematical model to minimize the resource block usage and maximize user access number, and the maximum independent set in graph theory to solve the theory.
For self optimizing energy saving switch based on case base, we analyzed how to according to the existing network load status and service request, adaptive to open or close the base station? "This problem. Constructed the minimum energy saving (MEC) optimization model and prove that the MEC problem is a NP-Hard problem, and then we put forward two a polynomial complexity algorithm to satisfy the self-organizing solution scalability characteristics. At the same time, we discuss how to apply these two algorithms to the network.
The results of this paper have certain guiding significance for the design of self organizing technical scheme in LTE network.

【學(xué)位授予單位】：中國科學(xué)技術(shù)大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2014
【分類號】：TN929.5

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相關(guān)期刊論文 前1條

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本文編號：1383607