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Research on the Handover of a Novel Cellular Architecture in Wireless Personal Communication Systems
ZHANG Zu-fan~ 《中国邮电高校学报(英文版)》2003,10(4)
1 IntroductionHandoverbetweencellsisplayinganimportantroleincellularcommunicationsystems[1~ 1 2 ] .Thehandoverprocedureanditseffectivenessareseriouslylimitedbythecellulararchitectureasaresultofmar ketplanning .Basedonthehexagonalcellulararchi tecture,manyhandoverprocedureshavebeendis cussedandevaluated ,andmostoftheimprovementproposedonthemleadstotheintroductionofsector ingcellularorlayeredcellularmodel.Otherwise ,abetterhandoverprocedureisessentialinmaintainingacallinprogressbutitreflectshi… 相似文献
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ZHANG Zu-fan DU Hui-ping JIANG Ze Chongqing University of Posts Telecommunications Chongqing China University of Electronic Science Technology of China Chengdu China 《中国邮电高校学报(英文版)》2006,13(4):29-33
1 Introduction The calling dwell time characteristic is critical for the user network planning and deployment, e.g., global system for mobile communications (GSM), as well as the next generation wireless multimedia networks, such as, the currently standar… 相似文献
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Femtocell技术以其较好的热点覆盖、较高的传输速率以及较大的网络容量,成为LTE网络中补充覆盖的重要途径之一。但同时,也造成了网络中复杂的CCI,严重影响了异构网络的性能。为了减少LTE双层网络中的CCI,提高网路容量,本文将基于MIMO的本征波束赋形、正交空时编码、天线选择技术应用于LTE双层网络,详细给出了无Femtocell覆盖半径、Femtocell最优密度以及Macrocell覆盖半径的精确数学表达形式,并对其所带来的干扰抑制效果进行了分析。通过仿真我们发现,相对于SISO来说,本征波束赋形的干扰抑制效果最好,可以使网络性能有个很大的提高,天线选择次之,正交空时编码所带来的增益最小,而当综合考虑性能增益以及复杂度的情况下,选择分集是一种比较合适的选择。 相似文献
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ZHANG Zu-fan 《中国邮电高校学报(英文版)》2005,12(3)
1 Introduction The performance analysis of co-channel interferenceincellular systems has been actively researched in the lastfewyears , due to the rapid deployment and success ofsuch systems , and because of the scarce bandwidthwhich calls for very careful design tools in order to uti-lizeit most efficiently.Signal transmission over a mobilechannel often suffers fromshadowing effect ,causing byobstacles in the radio propagation, such as the build-ings .In a cellular mobile system,the problemis… 相似文献
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This paper proposes rate-maximized (MR) joint subcarrier pairing (SP) and power allocation (PA) (MR-SP&PA),a novel scheme for maximizing the weighted sum rate of the orthogonal-frequency-division multiplexing (OFDM) relaying system with a decode-and-forward (DF) relay.MR-SP&PA is based on the joint optimization of both SP and power allocation with total power constraint,and formulated as a mixed integer programming problem in the paper.The programming problem is then transformed to a convex optimization problem by using continuous relaxation,and solved in the Lagrangian dual domain.Simulation results show that MR-SP&PA can maximize the weighted sum rate under total power constraint and outperform equal power allocation (EPA) and proportion power allocation (PCG). 相似文献
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In this paper,we focus on antenna array design for mobile phone with finite volume and propose a novel antenna element structure by capacitive feeding and capacitive loading method based on the planar ... 相似文献
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通过对LTE物理层关键技术分析,分别给出不同关键技术点的实现方法,从而设计了一种LTE物理层仿真系统平台,利用该平台对关键技术性能指标进行了仿真与分析.该仿真平台的设计方法和仿真分析结果对评估LTE标准有一定的指导意义和应用价值. 相似文献
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弹丸发射环境动态参数测试研究 总被引:1,自引:0,他引:1
为了准确测量引信在膛内及飞行过程的动态参数,设计了一种可置于引信内部的微型弹载测试仪,分析了仪器具有的功能和特点。研究了仪器的强化处理工艺及高效缓冲结构,并经过模拟应用环境下的校准,最终成功获取了某引信在膛内和发射过程的三轴加速度及转速信号。此研究对于引信、弹丸和火炮的设计、验收及研究有着十分重要的意义。 相似文献
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