适用于卫星通信的虚拟ARQ机制  

The Virtual ARQ Mechanism for Satellite Communications

作　　者：刘刚[1] 窦志斌[1] 国晓博[1] 

机构地区：[1]中国电子科技集团公司第五十四研究所,石家庄050081

出　　处：《载人航天》2015年第2期130-134,共5页Manned Spaceflight

基　　金：国家863计划(2012AA01A505)

摘　　要：随着载人航天技术的发展,越来越多的航天任务需要利用卫星通信进行信息传输。已有的研究成果大都采用了ARQ机制来降低卫星信道的数据丢失率。然而由于卫星信道还具有长时延的特点,因此ARQ所采用的反馈机制会大幅增加卫星信道的传输时延。为了克服卫星信道中反馈机制带来的大时延问题,提出了一种虚拟ARQ(Virtual ARQ,VARQ)机制。在VARQ中,发送端并不依靠接收端的反馈信息来进行分组重发,而只根据当时估计的丢包概率来决定传输策略,从而可以大幅降低卫星信道的传输时延。随后,还对VARQ所具有的一些时延性质进行了理论证明。仿真结果显示,相对于选择性重传ARQ机制,VARQ机制能够降低大约25.69%的时延。With the development of manned space technology,more and more space flight missions require information transmission via satellite communication. The existing research results mainly use ARQ mechanism to decrease the data loss probability of satellite channel. However,the acknowledgment mechanism of ARQ will highly increase the transmission delay of satellite channel. Therefore,a Virtual ARQ( VARQ) mechanism was proposed in this paper to decrease the transmission delay of satellite channel due to acknowledgment mechanism. In VARQ,the sender does not use the acknowledgment messages,and only use the estimated packet loss probability to decide the transmission policy. VARQ can highly decrease the transmission delay of satellite channel. In additon,the theoretical analysis of VARQ was also given. The simulation results showed that the VARQ mechanism could decrease the transmission delay by about 25. 69% as compared with the selective repeat ARQ.

关 键 词：卫星通信 长时延 ARQ VARQ 

分 类 号：V423.45[航空宇航科学与技术—飞行器设计] TN927[电子电信—通信与信息系统]