基于定向多波束智能天线的仿真分析-simulation analysis of directional multi-beam smart antenna.docx

AbstractSmart antenna technology in wireless communications can significantly increase the communication capacity and speed, reduce electromagnetic interference and reduce mobile phones and base stations transmitting power and it has the advantages of location .Therefore ,there has been paid more and more attention. However, because of the problem of self-adaptive smart antenna algorithm complexity and hardware processing speed of the bottleneck, at present it is hard to find a practical adaptive algorithm to enable adaptive smart antenna both in the harsh environment to work effectively and to make the signal to be real-time processed.Thus, we should pay much attention to a unpopular smart antenna named driectionl multi-beam smart antenna. During the theory reseach, the driection l multi-beam smart antenna can extend system capacity and reduce multipath interference. In this paper, in order to further study the theory and implementation issues, we should build a driectionl multi-beam smart antenna emulation system by “SystemView”.The emulation system emulates the driectionl multi-beam smart antenna from a system point of view.Firstly, we design the structure of the emunation system whice has three parts：wireless channel simulation,test bed simulation and switch beam algorithemsimulation.Secondly,the impact of radio environments on signals is discussed，especially the time delay and spatial spread caused by multipath propagation are reaseached.Radio channel models made by systemview for wireless communica- tion are given and also analyzed .Thirdly,we build a smart antenna test bed by software radio technology,des- ign test bed works in the IF，and focus on digital down-conversion.Finally, we build a complete emulation system which is built on the basis of in DS-CDMA and emulates the directionl milti-beam smart antenna for several times,and receive some good conclusions.Keywords: directionl milti-beam smart antenna ， Systemview ， digitaldown-conversion.第一章 绪论1.1 研究背景近