基于随机/自由和按需算法的卫星BoD多级MAC协议

针对全球没有统一BoD协议标准的问题,根据随机、自由和按需分配多址协议的特点,借鉴802.11分层协议工作原理,提出了一种新的BoD多级MAC协议,它根据地面站数量和系统业务量确定使用不同的协议,通过提高动态信道利用率达到降低平均传输时延的目的。理论分析和仿真结果表明,多级MAC协议在系统业务量小、地面站多时能得到小的传输时延;业务量增大后,在保持最大系统流量的同时仍能得到较小的传输时延,同时通过改进碰撞算法保证了系统的稳定性。

Multi-layered media access protocol based on aloha, random and DAMA for BoD satellite networks

Bandwidth-on-demand(BoD) protocol is a key multimedia access(MAC) protocol for the next generation satellite communication.Although a lot of companies claim owning BoD protocol with high performance,There are no any universal standards and implement ways at present.Short transmission delay and high throughput are always the final goal to pursue.Enlightened by the principle of MAC 802.11 protocol being classified,taking the advantage of ALOHA and CFDAMA respectively,this paper presents a new multiple MAC BoD protocol.By using unassigned slots more efficient,the new BoD protocol reduces the average delay further than the BoD protocol only based on CFDAMA.The results of the analysis and simulation show the proposed protocol has short transmission delay and high throughput and a proper protocol will be selected with varying amounts of earth stations and traffic load over satellite channels.Meanwhile a retransmitting strategy proposed here ensures the stabilization of the protocol.