發(fā)布時(shí)間：2018-02-15 21:42

  本文關(guān)鍵詞： LTE-A 中繼蜂窩系統(tǒng) 系統(tǒng)級(jí)仿真 資源調(diào)度算法　出處：《電子科技大學(xué)》2014年碩士論文　論文類(lèi)型：學(xué)位論文

【摘要】：LTE-A系統(tǒng)在數(shù)據(jù)速率、頻譜效率、時(shí)延等方面具有比LTE系統(tǒng)更高的需求。為了達(dá)到LTE-A的性能要求,3GPP提出了多用戶(hù)MIMO、多點(diǎn)協(xié)同、載波聚合和中繼等增強(qiáng)型技術(shù)。其中,中繼技術(shù)可以擴(kuò)大網(wǎng)絡(luò)覆蓋、有效消除盲區(qū)、提高系統(tǒng)吞吐量,以及降低網(wǎng)絡(luò)建設(shè)成本,已成為L(zhǎng)TE-A系統(tǒng)中的研究熱點(diǎn)。而中繼的引入增加了新的數(shù)據(jù)鏈路,增大了系統(tǒng)的資源消耗,使系統(tǒng)中的資源調(diào)度和分配問(wèn)題變得更加復(fù)雜,因此在中繼增強(qiáng)的蜂窩系統(tǒng)中進(jìn)行合理的資源調(diào)度以提高系統(tǒng)性能,具有重要的研究意義。本文首先詳細(xì)介紹了中繼技術(shù)并對(duì)中繼蜂窩系統(tǒng)進(jìn)行了概述,之后結(jié)合3GPP相關(guān)協(xié)議和提案,搭建了LTE-A TDD下行中繼系統(tǒng)級(jí)仿真平臺(tái),為后文的調(diào)度算法研究奠定了基礎(chǔ),并重點(diǎn)闡述了各中繼增強(qiáng)模塊的設(shè)計(jì),包括小區(qū)拓?fù)淠Ｐ�、無(wú)線(xiàn)信道建模、天線(xiàn)模型、用戶(hù)生成和接入選擇、接收上行反饋、資源調(diào)度模塊、鏈路質(zhì)量模塊以及鏈路性能模塊。其次,研究了傳統(tǒng)蜂窩系統(tǒng)的三種經(jīng)典調(diào)度算法:輪詢(xún)調(diào)度RR、最大載干比調(diào)度MAX C/I和比例公平調(diào)度PF,并在建立的中繼系統(tǒng)仿真平臺(tái)上實(shí)現(xiàn)了這三種算法,仿真結(jié)果顯示PF算法能獲得吞吐量和公平性的折中,達(dá)到相對(duì)較好的性能。然后,重點(diǎn)研究了中繼蜂窩系統(tǒng)的資源調(diào)度算法,分析了中繼蜂窩系統(tǒng)中常用的自適應(yīng)分布式比例公平ADPF調(diào)度算法,ADPF不能有效地保證backhaul和access鏈路吞吐量的平衡,公平性較差。隨后本文提出了一種基于中繼緩存的兩跳平衡分布式調(diào)度算法TBDRC。在第一跳調(diào)度時(shí),基站根據(jù)中繼的緩存信息自適應(yīng)調(diào)整平衡backhaul和direct鏈路占用的資源塊數(shù)目,以達(dá)到提高資源利用率、資源塊公平性和傳輸吞吐量的目的。在第二跳調(diào)度時(shí),中繼根據(jù)各中繼用戶(hù)的傳輸塊大小計(jì)算應(yīng)該給各中繼用戶(hù)分配的資源塊數(shù)目,避免了資源浪費(fèi),可以減少access和direct鏈路之間的干擾,提高用戶(hù)公平性。并在建立的中繼系統(tǒng)仿真平臺(tái)上實(shí)現(xiàn)了ADPF和TBDRC算法。通過(guò)與PF和ADPF算法進(jìn)行仿真比較,驗(yàn)證了TBDRC能通過(guò)平衡backhaul和access鏈路的吞吐量,大幅提高資源利用率和用戶(hù)公平性,并在一定程度上提高了系統(tǒng)吞吐量,能獲得系統(tǒng)吞吐量和用戶(hù)公平性的折中。最后,基于中繼系統(tǒng)仿真平臺(tái)和本文所提的TBDRC算法,從多方面評(píng)估了不同中繼數(shù)目對(duì)系統(tǒng)性能的影響。
[Abstract]:LTE-A system has higher demand than LTE system in data rate, spectrum efficiency, delay and so on. In order to meet the performance requirement of LTE-A, 3GPP has proposed multi-user Mimo, multi-point cooperation, carrier aggregation and relay, etc. Relay technology can expand network coverage, effectively eliminate blind areas, improve system throughput, and reduce network construction costs, which has become a research hotspot in LTE-A systems, and the introduction of relay has added new data links. It increases the resource consumption of the system and makes the problem of resource scheduling and allocation in the system more complicated. Therefore, reasonable resource scheduling is carried out in the relaying enhanced cellular system to improve the performance of the system. This paper introduces the relay technology in detail and gives an overview of the relay cellular system. Then the simulation platform of LTE-A TDD downlink relay system is built based on 3GPP protocols and proposals. It lays a foundation for the research of scheduling algorithm in the future, and focuses on the design of each relay enhancement module, including cell topology model, wireless channel modeling, antenna model, user generation and access selection, and receiving uplink feedback. Resource scheduling module, link quality module and link performance module. Secondly, In this paper, three classical scheduling algorithms for traditional cellular systems: polling scheduling, maximum load to interference ratio scheduling MAX C / I and proportional fair scheduling are studied, and these three algorithms are implemented on the established relay system simulation platform. Simulation results show that the PF algorithm can achieve a tradeoff between throughput and fairness, and achieve relatively good performance. This paper analyzes that the adaptive distributed proportional fair ADPF scheduling algorithm commonly used in relay cellular systems can not effectively guarantee the balance of backhaul and access link throughput. The fairness is poor. Then we propose a two-hop balanced distributed scheduling algorithm based on relay cache. In the first hop scheduling, the base station adaptively adjusts the number of resource blocks occupied by the balanced backhaul and direct links according to the buffer information of the relay. In order to improve resource utilization, resource block fairness and transmission throughput, in the second hop scheduling, relay calculates the number of resource blocks to be allocated to each relay user according to the size of each relay user, thus avoiding the waste of resources. It can reduce the interference between access and direct links and improve the user fairness. ADPF and TBDRC algorithms are implemented on the established relay system simulation platform. The simulation results are compared with PF and ADPF algorithms. It is verified that TBDRC can improve resource utilization and user fairness by balancing the throughput of backhaul and access links, improve system throughput to a certain extent, and achieve a compromise between system throughput and user fairness. Based on the relay system simulation platform and the TBDRC algorithm proposed in this paper, the effects of different relay numbers on the system performance are evaluated from many aspects.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：TN929.5

【參考文獻(xiàn)】

相關(guān)博士學(xué)位論文 前1條

1 馬彰超;中繼增強(qiáng)蜂窩系統(tǒng)的無(wú)線(xiàn)資源調(diào)度算法研究[D];北京郵電大學(xué);2011年

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本文編號(hào)：1513944