本文關(guān)鍵詞： 下一代超高速WLAN MAC 兩級(jí)調(diào)度 幀聚合 OPNET　出處：《電子科技大學(xué)》2013年碩士論文　論文類型：學(xué)位論文

【摘要】：無(wú)線局域網(wǎng)技術(shù)憑借其不可替代的優(yōu)勢(shì)，已經(jīng)融入到日常生活的方方面面，2012年2月24日，中國(guó)工業(yè)與信息化部發(fā)布公告，批準(zhǔn)《高頻譜利用率和高數(shù)據(jù)吞吐的無(wú)線局域網(wǎng)技術(shù)要求第1部分：超高速無(wú)線局域網(wǎng)媒體訪問(wèn)控制層（MAC）和物理層（PHY）》等兩項(xiàng)通信行業(yè)標(biāo)準(zhǔn)，即本文的主要技術(shù)研究背景：下一代超高速無(wú)線局域網(wǎng)技術(shù)（NUHT）。NUHT系統(tǒng)在頻譜效率、物理層傳輸速率和MAC層吞吐率等性能方面都有很明顯的提高，它以研制具有自主知識(shí)產(chǎn)權(quán)的高效中短距離通信系統(tǒng)為主要研究目標(biāo)。該標(biāo)準(zhǔn)通過(guò)改進(jìn)物理層以及MAC層接入技術(shù)，在采用感知無(wú)線電和頻帶聚合技術(shù)后，其最高吞吐量能夠達(dá)到1.2Gbps。 NUHT系統(tǒng)采用的接入機(jī)制是集中調(diào)度為主、競(jìng)爭(zhēng)接入為輔的這樣一種既保證系統(tǒng)吞吐量又兼顧BE業(yè)務(wù)靈活性的接入機(jī)制。針對(duì)這種情況，在只考慮集中調(diào)度的接入模型下，文章提出一種區(qū)分業(yè)務(wù)的幀聚合策略，將業(yè)務(wù)QoS等級(jí)、業(yè)務(wù)平均到達(dá)率、隊(duì)列時(shí)延緊迫程度等作為主要參數(shù)指標(biāo)，結(jié)合排隊(duì)論系統(tǒng)數(shù)學(xué)模型，采用非對(duì)稱、隊(duì)列容量有限的批量服務(wù)模型以及定額服務(wù)的方式對(duì)業(yè)務(wù)隊(duì)列進(jìn)行處理，最終得出每個(gè)隊(duì)列的聚合權(quán)重值，聚合模塊即可以按照隊(duì)列的聚合權(quán)重對(duì)各業(yè)務(wù)隊(duì)列進(jìn)行聚合操作，其中聚合權(quán)重表示每個(gè)業(yè)務(wù)隊(duì)列數(shù)據(jù)包在一次聚合幀中所占的比特百分比。這種調(diào)度和聚合模型可以優(yōu)先保證QoS業(yè)務(wù)需求，同時(shí)降低了幀頭、幀間間隔等一些冗余開(kāi)銷，仿真表明該區(qū)分業(yè)務(wù)的幀聚合模型可以優(yōu)先保證高優(yōu)先級(jí)業(yè)務(wù)，同時(shí)該方式比不區(qū)分業(yè)務(wù)的聚合機(jī)制以及經(jīng)典的WRR算法在隊(duì)列溢出率、平均隊(duì)列長(zhǎng)度等指標(biāo)上都有明顯優(yōu)勢(shì)。但是該模型在低到達(dá)率場(chǎng)景下性能明顯比較差，針對(duì)這種情況，文章又提出一種改進(jìn)放入觸發(fā)機(jī)制，最后通過(guò)仿真說(shuō)明該措施的有效性。 最終，本文在OPNET仿真平臺(tái)上搭建了下一代超高速無(wú)線局域網(wǎng)MAC層的簡(jiǎn)易模型，實(shí)現(xiàn)了MAC層業(yè)務(wù)流建立、修改、刪除，，帶寬申請(qǐng)（稍帶和單獨(dú)請(qǐng)求兩種方式）功能、業(yè)務(wù)隊(duì)列維護(hù)、聚合成幀、立即確認(rèn)（塊確認(rèn)和單幀確認(rèn)）、自動(dòng)重傳、分片和重組等基本功能，并在此平臺(tái)上驗(yàn)證了區(qū)分業(yè)務(wù)隊(duì)列的幀聚合策略的有效性。
[Abstract]:With its irreplaceable advantages, WLAN technology has been integrated into all aspects of daily life. In February 24th 2012, the Ministry of Industry and Information issued a notice. Approval of the Technical requirements for Wireless Local area Networks (WLAN) with High Spectral efficiency and High data throughput part 1: two communications industry standards: media access Control layer (MAC) and physical layer (PHY) for Ultra High Speed Wireless Local area Networks (WLAN). That is the main technical background of this paper: the next generation of ultra-high speed wireless local area network (WLAN) technology in the NUHT.NUHT system spectrum efficiency. Physical layer transmission rate and MAC layer throughput have been significantly improved. It aims to develop an efficient medium and short range communication system with independent intellectual property rights. This standard improves physical layer and MAC layer access technology, after adopting perceptual radio and frequency band aggregation technology. Its maximum throughput can reach 1.2 Gbps. The access mechanism used in NUHT system is centralized scheduling, supplemented by competitive access, which not only ensures the throughput of the system but also takes into account the flexibility of be services. Under the access model which only considers centralized scheduling, this paper proposes a frame aggregation strategy for traffic differentiation, which takes the QoS level of services, the average arrival rate of traffic, and the urgency of queue delay as the main parameters. Combined with the mathematical model of queuing theory, the batch service model with asymmetric, limited queue capacity and quota service are used to deal with the business queue. Finally, the aggregate weight of each queue is obtained. The aggregation module can aggregate each business queue according to the aggregation weight of the queue. The aggregation weight represents the bit percentage of each service queue packet in an aggregated frame. This scheduling and aggregation model can first guarantee the QoS traffic requirements while reducing the frame header. Some redundant overhead such as inter-frame interval, simulation shows that the frame aggregation model of differentiated services can give priority to high-priority services. At the same time, this method is better than the aggregation mechanism which does not distinguish traffic and the classical WRR algorithm in queue overflow rate. The average queue length has obvious advantages, but the performance of the model is obviously poor in the low arrival rate scenario. In view of this situation, this paper proposes an improved trigger mechanism. Finally, the effectiveness of the measure is demonstrated by simulation. Finally, this paper builds a simple model of the next generation ultra-high speed WLAN MAC layer on the OPNET simulation platform, and realizes the establishment, modification and deletion of MAC layer traffic. Bandwidth request (both slightly and individually requested) functions, service queue maintenance, aggregation into frames, immediate confirmation (block confirmation and single frame confirmation, automatic retransmission, slicing and reorganizing, and other basic functions). The effectiveness of the frame aggregation strategy is verified on this platform.
【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】：2013
【分類號(hào)】：TN925.93

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 羅振東;;下一代WLAN技術(shù)標(biāo)準(zhǔn)802.11ac/ad[J];現(xiàn)代電信科技;2010年12期

2 王思明,汪虹;批量服務(wù)容量有限的多隊(duì)列循環(huán)系統(tǒng)[J];系統(tǒng)工程理論與實(shí)踐;1998年09期

本文編號(hào)：1453252