CAJ | 학술논문

当网络节点采用 CSMA ／CA 算法竞争访问信道时，会引起退避失败，停止发送数据。针对退避失败概率的问题，提出一种基于马尔可夫链的分析方法。首先，建立饱和负载状态下的离散马尔可夫链数学模型，然后推导退避失败概率与退避次数、退避指数、节点数量之间的关系，最后分析 CSMA ／CA 算法的参数和网络规模对退避失败概率的影响。实验结果表明，利用 NS-2仿真器评价的结果和数学模型分析的结果大致相同，该数学模型能够有效分析退避失败概率。
당망락절점채용 CSMA ／CA 산법경쟁방문신도시，회인기퇴피실패，정지발송수거。침대퇴피실패개솔적문제，제출일충기우마이가부련적분석방법。수선，건립포화부재상태하적리산마이가부련수학모형，연후추도퇴피실패개솔여퇴피차수、퇴피지수、절점수량지간적관계，최후분석 CSMA ／CA 산법적삼수화망락규모대퇴피실패개솔적영향。실험결과표명，이용 NS-2방진기평개적결과화수학모형분석적결과대치상동，해수학모형능구유효분석퇴피실패개솔。
When the network nodes contending for channel access using CSMA /CA algorithm,the backoff failure is caused,and data transmission is stopped as well.Aiming at the problem of backoff failure probability,we proposed a Markov chain-based analysis method. First,we built the discrete Markov chain model in saturated traffic scenarios,and then deduced the relations between the backoff failure probability and the backoff times,the backoff indices and the node numbers.Finally we analysed the impact of the CSMA /CA algorithm parameters and wireless sensor network scale on backoff failure probability.Experimental result showed,it was almost the same in the results evaluated by the NS-2 simulator and analysed by the mathematical model respectively,the mathematical model can effectively analyse the backoff failure probability.