摘要
对智能天线在移动AdHoc网络(MANET)中的应用进行了研究.提出了自适应波束形成CSMA/CA(ABF CSMA/CA)协议.该协议利用RTS/CTS短分组对话实现信道预约,在RTS与CTS分组前设置了训练序列,收发节点的智能天线基于训练序列进行波束形成以传输数据分组与ACK.提出改进的"虚拟载波监测"机制进行冲突避免(CA).每个节点中设置两类网络分配矢量(NAV),用一个oNAV记录邻节点以全向模式占用信道的时间,用多个bNAV分别记录各邻节点以波束形成模式传输分组的时间.推导了信道利用率的近似计算公式并进行了仿真.结果表明,ABF CSMA/CA协议与智能天线的结合能够有效实现信道的空分复用(SDMA),显著提高网络的信道利用率.
The medium access control (MAC) protocol for supporting the application of smart antennas in the mobile Ad Hoc network (MANET) is studied. An adaptive beamforming CSMA/CA protocol (ABF-CSMA/CA) is proposed. In ABF-CSMA/CA, the RTS/CTS dialogue is used and training sequences are transmitted just before RTS and CTS packets, so the temporal reference beamforming (TRB) can be performed. An improved virtual carrier-sense mechanism is also proposed to enhance collision avoidance (CA) and obtain efficient space division multiple access (SDMA). In this scheme, every node has two kinds of network allocation vector(NAV)- oNAV and bNAV. A theoretical analysis of channel utilization is presented. Results show that the ABF-CSMA/CA protocol can support the application of smart antennas effectively and provide higher channel utilization.
出处
《西安电子科技大学学报》
EI
CAS
CSCD
北大核心
2003年第3期309-314,共6页
Journal of Xidian University
基金
国家自然科学基金资助项目(69872028)
国家863计划重大课题(2001AA123031)
高等学校优秀青年教师教学科研奖励计划资助
关键词
智能天线
移动ADHOC网络
应用
多址接入协议
自适应波束形成CSMA/CA协议
Carrier sense multiple access
Cochannel interference
Code division multiple access
Communication channels (information theory)
Mobile antennas
Mobile telecommunication systems
Space division multiple access
