Smart Antenna Scdma Wireless Access System Performance

During the past years, Wireless Access Network has made a great progress. The number of the subscribers has been increasing rapidly, at the same time, there is a great demand for higher quality service, more kinds of wireless services and much higher data rate service. Therefore, how to use the precious wireless resources efficiently has become an urgent problem. SCDMA Wireless Access Network, the newborn wireless communication system, uses many up-to-date techniques, such as Smart Antennas, to solve the problem. Since TD-SCDMA proposal is one of third-generation telecommunication standard in the world, so the SCDMA access system which working at TDD mode represents the future communication business development.In this thesis, we introduce the Smart Antennas and mainly examine the performance enhancements that can be achieved by employing SA in SCDMA wireless access system.In the part of introduction of Smart Antennas, we discuss the Switched-Beam Arrays realizing by mending Butler Network at first. Then we compare the different beam forming algorithms in SA. Simulations of the beam forming are given in each discuss.In order to examine the enhancements of capacity by employing Smart Antennas, we set up a system-analyzing model, which includes the propagation waste model and interference model. According to the models, we study the capacity of SCDMA system. The simulations and analytical results are reasonable. In the paper, we also discuss the performances by employing different antenna systems. The conclusion shows that the Smart Antennas at the base station can dramatically improve the system performance.Since there is a lack of the researches on performance in SCDMA wireless access network, so the study of the paper is very necessary.