本文研究将智能天线应用于分组无线网络中,提出了支持智能天线应用的自适应时隙分配多址接入协议(ASAMA).该协议采用时分双工(TDD)方式,每一帧开始时用户节点依次发送训练序列,基站的智能天线据此计算出各用户节点的空间特征(Spatial Signature).基于波束形成的信干噪比最大化准则,设计了逐点优化与全局优化两种不同复杂度的时隙分配算法.由基站对上下行业务的时隙进行动态分配,在保证通信质量的前提下,使每个时隙容纳多个数据分组,以充分实现信道的空分复用(SDMA).对该协议的信道利用率进行了近似分析,并利用仿真方法考察其性能.结果表明,ASAMA协议能有效支持智能天线应用并具有很高的信道利用率与良好的时延性能.

Employing smart antennas in the basestation of packet radio network is studied.An adaptive slot allocation multiple access protocol (ASAMA) is proposed.In ASAMA protocol,Time-Division Duplexing is adopted,and pilot signals are transmitted orderly by mobile terminals (MTs) at the beginning of one frame,so the spatial signatures of MTs can be obtained by the smart antennas.Based on the optimal SINR beamforming method,two slot allocation algorithms,which are point-by-point optimizing (PPO) and global optimizing (GO),are presented.On condition that all packets can be received successfully,the basestation dynamically schedules uplink and downlink traffic to achieve that several data packets can be simultaneously transmitted in one traffic slot.Therefore,efficient space-division-multiple-access (SDMA) can be obtained.Approximate analysis of channel utilization is presented.Simulations show that ASAMA protocol effectively supports the application of smart antennas and provides higher channel utilization and lower delay.