| Due to the enormous performance gains associated with the use of smart antenna in wireless communications, smart antenna has received intense attention. There exist many adaptive algorithms those can be used in smart antenna systems, but with the limitation of the complexity of the algorithms and the processing speed, it is difficult to find a universal and practical algorithm for designing the smart antenna system with acceptable complexity and excellent real-time processing ability in various adverse signal environments.Thus, we pay attention to a new smart antenna - directional multi-beam smart antenna which can realize SDMA by directional antennas array. During the theory research, the directional multi-beam smart antenna can extend system capability and reduce the multipath interference. So we build a directional multi-beam smart antenna emulation system by "Systemview" for researching the theory further and the realization problem. The emulation system emulates the directional multi-beam smart antenna from a system point of view, and combines SDR to solve the problem of realization.First of all, we design the structure of the emulation system which have 3 parts: wireless channel simulation, test bed simulation and switch beam algorithm simulation.Secondly, the impact of radio environments on signals are discussed, especially the time delay and spatial spread caused by multipath propagation are researched. Also, radio channel models made by Systemview for wireless communication are given and analyzed.Thirdly, smart antenna test bed is designed by SDR technology. The test bed works in the IF. The linchpin technology of the test bed is digital down-conversion.Finally, we introduce the realization of switch beam algorithm by MATLAB and combine the 3 parts of the emulation system for building a complete emulation system. This system is built on the basis of in DS-CDMA and emulates the directional multi-beam smart antenna for several times, and received some conclusions.
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