CAJ | 학술논문

分析了采用网络编码和机会路由方法的无线多跳网络中存在的信道接入问题，建模描述了802．11 DCF广播信道接入过程，并对影响无线多跳网络的吞吐率、延迟、信道资源分配等性能指标的因素进行了定量分析．利用M/M/1/K队列和离散时间的二维Markov链，建模描述具有相异报文到达速率的多个节点竞争信道时各个节点上的报文到达、排队、信道接入和发送过程．通过求解该模型，得到各节点的实际发送速率、报文平均服务时间和系统总吞吐率等指标的计算公式．将模型计算结果和基于NS-2网络模拟平台得到的实验结果进行对比．结果表明，该模型能够有效地预测各种传输负载组合情况下的报文平均服务时间和信道资源分配的公平性等网络性能指标．
분석료채용망락편마화궤회로유방법적무선다도망락중존재적신도접입문제，건모묘술료802．11 DCF엄파신도접입과정，병대영향무선다도망락적탄토솔、연지、신도자원분배등성능지표적인소진행료정량분석．이용M/M/1/K대렬화리산시간적이유Markov련，건모묘술구유상이보문도체속솔적다개절점경쟁신도시각개절점상적보문도체、배대、신도접입화발송과정．통과구해해모형，득도각절점적실제발송속솔、보문평균복무시간화계통총탄토솔등지표적계산공식．장모형계산결과화기우NS-2망락모의평태득도적실험결과진행대비．결과표명，해모형능구유효지예측각충전수부재조합정황하적보문평균복무시간화신도자원분배적공평성등망락성능지표．
Channel access problems in wireless multi-hop networks adopting network coding and op-portunistic forwarding technologies are analyzed.A model for an 802.1 1 distributed coordination function (DCF)broadcast channel access process is built to quantitatively analyze the factors that af-fect the performance including the throughput,delay and fairness in wireless multi-hop networks. Behaviors of nodes such as packet arriving,queuing,channel access and sending are modeled based on an M/M/1/K queue and a two-dimensional discrete-time Markov chain when these nodes have different packet arriving rates.By solving the model,equations are obtained to calculate several per-formance indices such as the actual transmission rate and packet service time on each node and the total throughput of the system.Results generated by the model are compared with experimental re-sults from a simulation based on the NS-2 platform.It is shown that the model can effectively predict transmission performance indices including average packet service time and fairness of channel re-source allocation under various traffic load combinations.