【摘要】 媒体接入控制协议设计的基本目标是协调包的传输,实现高的信道吞吐量,低的传输时延,低复杂度的控制算法,信道的稳定性,协议的可扩展性和信道的再配置性。本文对卫星通信中的MAC协议进行了概括,分类和性能分析,并且研究了一组性能优越的混合式协议。最后针对下一代宽带卫星网络支持的业务特点,提出了一种适合多业务的高轨卫星媒体接入控制协议。对于恒定比特率的业务(CBR)采用固定分配的方式;对于实时/非实时可变率业务(rt/nrt-VBR)采用选择性轮询预约和捎带预约相结合的按需分配和加权自由分配的方式;对于非限定比特率业务(UBR)采用自由分配的方式。通过分析表明,协议在时延和吞吐量性能上能取得好的性能。更多还原

【Abstract】 Fundamental objectives in the design of medium access control(MAC) protocols are coordinating transmission of packets,and realizing high channel throughout,low transmission delay,low complexity of the control algorithm,channel stability,protocol scalability,and channel reconfigurability.This paper presents a survey,classifications and performance assessments of MAC protocols for satellite communications.In the end,the paper presents a novel multimedia access control protocol that is designed for next-generation geostationary broadband satellite communication.For constant bit rate service,it uses Fixed Assignment;for real time/non-real time variable bit rate service,it uses optional round-robin and piggy-backing reservation request CFDAMA;for unspecified bit rate service,it uses free assignment.Analysis results show that the protocols can realize good performance in delay and throughout.更多还原