本文選題：寬帶衛(wèi)星通信 + 多址接入�。� 參考：《重慶大學》2014年碩士論文

【摘要】：寬帶衛(wèi)星網絡作為地面網絡的補充和延伸，是未來空天地一體化網絡系統(tǒng)的重要組成部分。然而衛(wèi)星通信的帶寬是有限的，如何在有限資源下提高信道利用率并滿足用戶業(yè)務服務質量是多址接入與帶寬分配策略研究的關鍵問題。目前一些傳統(tǒng)的多址接入與帶寬分配策略能夠對連續(xù)數據流業(yè)務和語音業(yè)務實現較高信道利用率和較低端到端時延，但是針對具有較強突發(fā)性多媒體業(yè)務和多樣化業(yè)務需求，這些技術已不能勝任。 本文系統(tǒng)研究了已有多址接入與帶寬分配策略，在基于帶寬按需分配的寬帶衛(wèi)星網絡下提出了一種改進的信道接入協(xié)議CFDAMA-FP，，并同時改進了其中的帶寬分配算法，旨在提高信道利用率和業(yè)務服務質量，適應業(yè)務突發(fā)特性。本文主要工作有： （1）基于混合按需/自由分配的多址接入協(xié)議CFDAMA采用自由分配時隙有效降低了平均傳輸時延，但隨著信道負載增大，自由分配時隙減少而預約次數增多造成網絡性能下降。針對這個問題，提出具有快速反應機制的多址接入協(xié)議。該協(xié)議改進隨機接入算法，降低了接入碰撞概率；然后，繼承基于突發(fā)目標的接入思想，采用在得到資源分配后周期發(fā)送帶寬需求更新信息的方式，代替反復申請資源的預約方式，能有效降低平均接入時延；最后，本文建立了接入端到端時延計算模型，證明了該協(xié)議能夠減少接入時延和平均傳輸時延； （2）在帶寬按需分配策略中，帶寬申請到分配的時延過長造成資源浪費，傳統(tǒng)分配方式采用預測業(yè)務策略來合理利用這段時延，但是由于業(yè)務高突發(fā)性，預測值和實際業(yè)務很難達到一致，本文提出基于預約的帶寬請求分配算法。首先，采用基于最大Lyapunov指數的混沌時間序列信源預測算法，該算法對高突發(fā)性信源具有較好預測性；然后，利用實際分配結果反饋控制預約申請，優(yōu)化帶寬分配結果，有效維持了用戶隊列穩(wěn)定性，降低了業(yè)務時延抖動；最后，為了滿足不同等級業(yè)務性能需要，將業(yè)務要求作為優(yōu)先級排序分配依據，提高了業(yè)務性能和用戶接入公平性； 最后，通過對CFDAMA-FP進行建模實現和對比仿真，結果表明在具有高突發(fā)特性的Pareto ON-OFF信源模型下，CFDAMA-FP能夠在高突發(fā)信源和用戶數目較大的條件下提供比CFDAMA-PA和CFDAMA-PB更優(yōu)的平均端到端時延/吞吐量性能和更好的用戶接入公平性能。
[Abstract]:As a supplement and extension of terrestrial network, broadband satellite network is an important part of future integrated space and earth network system. However, the bandwidth of satellite communication is limited. How to improve the channel utilization and satisfy the quality of service (QoS) is the key problem in the research of multiple access and bandwidth allocation strategy. At present, some traditional multiple access and bandwidth allocation strategies can achieve higher channel utilization and lower end-to-end delay for continuous data flow services and voice services, but for the demand of strong burst multimedia services and diversified services, some traditional multiple access and bandwidth allocation strategies can achieve higher channel utilization and lower end-to-end delay for continuous data flow services and voice services. These techniques are no longer up to the mark. In this paper, the existing multiple access and bandwidth allocation strategies are systematically studied. An improved channel access protocol, CFDAMA-FPFP, is proposed for broadband satellite networks based on bandwidth allocation on demand, and the bandwidth allocation algorithm is also improved. The purpose of this paper is to improve channel utilization and quality of service (QoS) and adapt to service burst characteristics. The main work of this paper is as follows: 1) CFDAMA, a hybrid on-demand / free allocation multiple access protocol, effectively reduces the average transmission delay by free allocation of time slots. However, with the increase of channel load, the number of free allocated slots decreases and the number of reservations increases, which results in network performance degradation. To solve this problem, a fast response multiple access protocol is proposed. The protocol improves the random access algorithm and reduces the access collision probability. Then, it inherits the access idea based on the burst target and transmits the bandwidth requirement update information in the period after the resource allocation. Instead of the reservation mode of repeatedly requesting resources, the average access delay can be reduced effectively. Finally, the end-to-end delay calculation model is established, which proves that the protocol can reduce the access delay and average transmission delay. 2) in the bandwidth allocation strategy, the delay of bandwidth allocation is too long, which results in waste of resources. The traditional allocation method uses the predictive service strategy to make use of the delay reasonably, but because of the high traffic burst, the traditional allocation method uses the predictive service strategy to make use of the delay reasonably. It is difficult to match the predicted value with the actual traffic. In this paper, a bandwidth request allocation algorithm based on reservation is proposed. First of all, chaotic time series source prediction algorithm based on maximum Lyapunov exponent is adopted, which has good predictability for high burst source, and then the bandwidth allocation result is optimized by feedback control of reservation application based on actual allocation result. It can effectively maintain the stability of the user queue and reduce the delay jitter. Finally, in order to meet the performance needs of different traffic levels, the traffic requirements are taken as the priority allocation basis, which improves the service performance and user access fairness. Finally, through modeling and simulation of CFDAMA-FP, The results show that CFDAMA-FP can provide better average end-to-end delay / throughput performance and better fair access performance than CFDAMA-PA and CFDAMA-PB in the case of high burst source and large number of users under the Pareto ON-OFF source model with high burst characteristics.
【學位授予單位】：重慶大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TN927.2

【參考文獻】

相關期刊論文 前7條

1 李斗;姬冰輝;王峰;項海格;;基于混沌預測的寬帶DVB-RCS衛(wèi)星接入信道動態(tài)分配方案研究[J];電子與信息學報;2008年03期

2 呂強;馮tD;劉乃金;;寬帶衛(wèi)星通信產業(yè)與技術發(fā)展研究[J];國際太空;2012年05期

3 朱子行;梁俊;余江明;;臨近空間通信網MAC層協(xié)議研究[J];計算機工程與應用;2011年02期

4 趙玲;劉建華;;OPNET網絡仿真技術及其應用[J];微計算機信息;2010年13期

5 楊紹清,章新華,趙長安;一種最大李雅普諾夫指數估計的穩(wěn)健算法[J];物理學報;2000年04期

6 佘陽,周熙,周山泉,郝華;GEO衛(wèi)星網絡CFDAMA-CFA協(xié)議性能分析[J];無線電通信技術;2005年05期

7 劉悅;;全球商業(yè)寬帶衛(wèi)星市場發(fā)展分析[J];衛(wèi)星應用;2012年01期

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