简介：Thesum-ratecapacityofCDMAandTDMAinvectorbroadcastchannelisresearched.Anupperboundofsum-ratecapacityinCDMAsystemandalowerboundofsum-ratecapacityinTDMAsystemarederivedrespectively.Accordingtothesetwobounds,theratioofthetwoboundsatmostcanachievemin(M,K).HereMistheantennanumberofthetransmitterandKisthenumberoftheuserinthisvectorbroadcastchannel.

简介：在覆盖无线特定的网络的分析，内在的节点分布通常被假定是二独立同类的泊松点进程。在这份报纸，由使用随机的几何学工具，一个新不同类的覆盖无线特定的网络模型被学习，停止概率被分析。由假定那主要(PR)网络节点作为一个泊松点过程(PPP)被散布并且第二等(SR)网络节点作为Matern簇被散布过程，一上面并且一为主要网络和第二等的网络的传播能力的更低的界限被介绍。模拟结果证明PR和SR网络的传播能力将两个都由于SR网络的不同类有小增长。

简介：Heterogeneouscellularnetworksimprovethespectrumefficiencyandcoverageofwirelesscommunicationnetworksbydeployinglowpowerbasestation(BS)overlappingtheconventionalmacrocell.ButduetothedisparitybetweenthetransmitpowersofthemacroBSandthelowpowerBS,cellassociationstrategydevelopedfortheconventionalhomogeneousnetworksmayleadtoahighlyunbalancedtrafficloadingwithmostofthetrafficconcentratedonthemacroBS.Inthispaper,weproposeaload-balancecellassociationschemeforheterogeneouscellularnetworkaimingtomaximizethenetworkcapacity.Byrelaxingtheassociationconstraints,wecangettheupperboundofoptimalsolutionandconverttheprimalproblemintoaconvexoptimizationproblem.FurthermoreweproposeaLagrangemultipliersbaseddistributedalgorithmbyusingLagrangedualtheorytosolvetheconvexoptimization,whichconvergestoanoptimalsolutionwithatheoreticalperformanceguarantee.Withtheproposedalgorithm,mobileterminals(MTs)needtojointlyconsidertheirtraffictype,receivedsignal-to-interference-noise-ratios(SINRs)fromBSs,andtheloadofBSswhentheychooseserverBS.SimulationresultsshowthattheloadbalancebetweenmacroandpicoBSisachievedandnetworkcapacityisimprovedsignificantlybyourproposedcellassociationalgorithm.

简介：在我们调查了的这份报纸，downlink的表演概括了分布式的天线系统(GDAS)。在空间相关褪色的条件的假设下面，我们根据Bessel功能的系列导出相关系数的数字表达式，并且提起了事件的吝啬的角度的范围限制。而且，当我们从空空间使用了基础向量而不是直角的集合获得一样的系统性能时，分布式的概括分层的空间时间代码(GLST)的体系结构被认为以便完成multiplexing获得和差异获得但是与更低的复杂性。而且，以便最大化能力，Gerschgorin圆基于快天线选择算法包括那些模拟结果的讨论被评估了。

简介：CapacityofMIMOLAS-CDMAsystemsundermulti-pathfadingchannelswithtwodifferentcorrelatingmodelswerestudiedinthepaper.Influencesofthetwomodelsparametersoncapacitywereanalyzed.Thenumericalresultspresentthat:accordingtotheVariousScatteringEnvironmentscorrelatingmodel,whentheinner-elementsdistanceofantennasarrayislargethan0.5λ,correlationalmostdoesnottakefromthesystemcapacity;fortheSalz-Wintercorrelatingmodel,thespreadangleatreceiveristheotherkeyfactor,italsoinfluencethesystemcapacitygreatly.

简介：Inthisarticle,resultsobtainedfromwidebandmultiple-inputmultiple-outputchannelmeasurementsat4.9GHzarepresented.Measurementswereperformedinanindoorhotspotscenariowithbothline-of-sightandnon-line-of-sightpropagationconditions.Verticalpolarizeduniformlineararrays(ULAs)withdifferentantennaspacingandorientationwereutilizedforinvestigatingtheimpactofantennaconfigurationsonthesystemperformance.Basedonmeasuredchannelimpulseresponses,thespatialcorrelationofULAisanalyzedandcomparedwiththetheoreticalvaluescalculatedfromthepowerazimuthspectrum.Followingthat,theeigenvaluestatisticsandcapacitywithrespecttoantennaspacingandorientationaregivenandcompared.Thediversity-multiplexingtradeoff(DMT)ofmeasuredchannelsatoperationalsignal-to-noiseratio(SNR)isalsopresented.ThereasonwhytheDMTofmeasuredchannelsismuchlowerthanthatofi.i.d.Rayleighchannelsisspecified.

简介：Femtocell是一种有希望的技术与低力量、费用有益的小基础车站改进网络性能。然而，在femtocell网络的干扰有限现实使干扰和资源管理成为钥匙到完成femtocell网络的好处。在这份报纸，下列贡献一步一步地被做：首先，根据在技术和第三产生合伙的网络建筑学投射的认知无线电(CR)(3GPP)的干扰温度模型(ITM)，长期的进化进展了(LTE--一)，优化再使用femtocell的子通道的能力的问题模型在划分策略的频率下面被建立，联合考虑平均干扰限制和即时干扰限制。第二，利用凸的理论，再使用femtocell的子通道的最佳的力量分配被导出。第三在使隧道褪色的瑞利下面，子通道的靠近形式的表情可重用的概率和能力被导出。最后，数字结果被进行到证实我们的分析结果，它能为femtocell网络推广的频率资源分配提供理论指导。

简介：Inthispaper,thecapabilityofIEEE802.11bDistributedCoordinationFunction(DCF)modesupportingofConstantBitRate(CBR)andVariableBitRate(VBR)VoiceoverIP(VoIP)trafficisinvestigated.Then,thecapacityof802.11bWirelessLocalAreaNetwork(WLAN)systemcarryingvoicecallsinawiderangeofscenarios,includingvaryingdelayandpacketlossrateconstraintsisanalyzedandevaluated.BothG.711andG.729voiceencodingschemesandarangeofvoiceinter-arrivaltimeareconsidered.Theanalysesandsimulationresultsshowthatcapacityishighlysensitivetothedelaybudgetallocatedtothesumofpacketizationandwirelessnetworkdelays.Foragivenpacketlossrateconstrained,G.729isshowntohaveacapacitygreaterthanthatwhenG.711isused.ThesimulationresultsshowthatbysupportingVBRunderDCFmodethenetworkhastheapproximatelytwicemuchcapacityassupportingCBRhas,regardlessoftheencodingschemesandtheinter-arrivaltime.