【作者】 赵伟；

【导师】 周杰；

【作者基本信息】 南京信息工程大学 ， 系统分析与集成， 2007， 硕士

【摘要】 分层小区系统无线资源管理技术的研究是小区无线通信系统研究的关键和热点领域。无线小区移动通信网所能获得的无线资源是有限的。要支持广泛的业务，提高业务的服务质量以及通信系统的性能有赖于对无线资源的合理利用。作者在在第二章和第三章叙述了系统所需的理论结构，建立了由宏小区层，微小区层和皮小区层构成的多码CDMA系统分层小区模型。第四章中通过使用智能天线，给出高性能的层次化CDMA移动通信网络的设计策略。重点是对微小区到皮小区所需的功率分析，以及小区天线倾斜角度对系统性能提高的影响。结论表明系统性能取决与小区位置和天线倾斜角度。通过定义干扰平衡因子得到最优的小区天线倾斜角度。作者在分析过程中，对CDMA系统的上行链路容量进行了分析，不同的是，通过将阴影和距离看成两个作用于传播信号的相关过程。计算了传播损耗因子的概率密度函数从而得到上行链路干扰的统计特征。论文在第五章提出了一种分层小区系统的多业务呼叫接纳控制策略，更符合实际情形以及未来发展趋势。多业务呼叫接纳控制策略兼顾，移动性和小区信道利用率。减少了呼叫的切换频度，降低了系统的信令开销。作者论文中阐述的内容不仅仅针对第三代无线移动通信系统，其中也包含第二代无线移动通信系统的部分内容。更多的内容具有普遍的应用参考价值，可以延伸到未来的无线移动通信系统中去。更多还原

【Abstract】 As a key technology, the wireless spectral resource management of’ hierarchical cellular systems (HCSs) has been a hot spot area and many researches centering on it have been done. Wide service supports and high Quality of Service (QoS) depend on the efficient allocation and utilization of spectrum resource due to limited affordable spectral resources.In chapter 2 and 3, theories this system required are stated, such three layers as macro-cell layer, micro-cell layer and picro-cell layer construct a cellular model. In chapter 4, we present hierarchical cell deployment strategies for designing a high capacity cellular mobile radio system by using tilt antennas. The focuses are on the ratio of required receive power of micro-cell to that of the picro-cell and the tilt angle of the microcell antenna to increase the system capacity. We show the system capacity is dependent on the location of picro-cell and the tilt angle. The optimal tilt angle of picro-cell is obtained by defining the interference trade-off factor that will be used to maximize the capacity. Chapter 6 analyzes the uplink capacity of a cellular CDMA system. Compared to other methods in literatures, the solution of ours to this problem fits real environments better. Such two random processes as shadowing and distance play effects on the propagating of signals. Based on this assumption, the statistics of the outer interference are available.In chapter 5 An layer-selection strategy of HCSs is stated, which is more fit to the real conditions. On this basis, with channel utilities and mobility characteristics considered, a novel multi-services call admission control strategy is submitted. It is validated to be superior to the fixed threshold call admission control strategy commonly used and decreases the signaling loads and the handoff frequency.What we listed in this paper does not necessarily deal with the third or second generation wireless mobile communication systems, more have universal applications leading to future ones.更多还原