基于跨层的自适应预留带宽和多重QoS保证的EDCA流接纳控制  

Per-flow Admission Control with Adaptive Reservation of Bandwidth and Multiple QoS Support in EDCA of IEEE 802.11e Based on Cross-layer Design

作　　者：曾菊玲[1] 蒋砺思[2] 

机构地区：[1]三峡大学计算机与信息学院,宜昌443002 [2]北京邮电大学信息与通信工程学院,北京100876

出　　处：《计算机科学》2012年第8期130-135,共6页Computer Science

基　　金：三峡大学自然科学基金(KJ2011B042)资助

摘　　要：提出了基于跨层的自适应带宽预留和多重QoS保证的802.11eEDCA分布式流接纳控制。首先自适应分配各站点OFDM子载波比特以最大化信道容量,并将比特率跨层传送到MAC层。基于此,提出了基于分布式测量的动态带宽预留机制,使预留带宽自适应各用户信道特点和业务特征;提出了半模式化的中心控制的剩余因子估计方法,从而克服了直接测量的不准确性和分布式估计的局部性,并降低了计算复杂度;提出了基于协议模型的带宽和碰撞率双重接纳标准,使多重QoS参数同时得到保证。通过这些措施得到自上至下的自适应接纳控制。仿真表明,提出的接纳控制机制能较大地提高资源利用率,更好地保证业务质量。A novel dynamic distributed admission control with adaptive reservation of bandwidth and multiple QoS support of EDCA（enhanced distributed channel access） in IEEE802.11e based on cross-layer was presented.In this mechanism,the bits of the subcarrier of OFDM in the station are allocated to obtain the maximum channel capacity subjected to the maximum power at first and the bit rate is transmitted to the medium access control layer at the same time.By means of that,a dynamic reservation of the bandwidth was presented based on the distributed measurement,which adapts to the characteristics of the channel and the service.And an estimation of the surplus factor by center control half-based on model was presented,which overcomes the un-accuracy resulted by directed measuring and locality resulted by distributed estimation.The relationship between the service’s parameters and the collision probability was obtained and the double admission criteria of the bandwidth and the collision probability was suggested to support the multiple QoS such as bandwidth and delay as well as error ratio of the frame.All above suggestions structure an adaptive admission control from the upper layer to the lower layer.The simulation shows the admission control presented outperforms the former in the utilization of the resource and the quality of the service.

关 键 词：分布式流接纳控制 OFDM子载波比特分配 动态带宽预留 碰撞概率及剩余因子计算 多重QoS保证 

分 类 号：TN915[电子电信—通信与信息系统]