简介:Orthogonalfrequencydivisionmultiplexing(OFDM)whichhasbeenadoptedinthelong-termevolution(LTE)systemcanimprovethesystemcapacityobviously.However,italsobringsaboutsevereinter-cellinterference(ICI)forcell-edgeusers(CEUs).Totacklethisproblem,multi-userselectionandpowercontrol(MuS-PC)isproposedasanefficientschemeinuplinkcoordinatedmulti-pointmulti-usermulti-inputmulti-output(CoMP-MU-MIMO)transmission/reception.Thispaperjointlyconsidersuser’ssignaltointerferenceplusnoiseratio(SINR)andproportionalfairness(PF)tomaximizethetotalchannelcapacityinmulti-userselectionbyformulatingapenaltyfunction.Tosimplifythepenaltyfunction’scomputation,particleswarmoptimization(PSO)algorithmisintroduced.Inaddition,powercontrolisadoptedtomaximizeoverallenergyefficiency.SimulationresultsdemonstratethattheMuS-PCschemecannotonlyobtaintheoptimaltotalchannelcapacitywhileguaranteeeachuser’squalityofservice(QoS)andPF,butalsolargelyreducecomputationalcomplexityandimproveenergyefficiency.Asaresult,thepoorcommunicationqualityofCEUscanbeenhanced.
简介:摘要:本文主要对MU-MIMO功能进行介绍,验证了不同负荷小区开通MU-MIMO特性后对下行感知速率的提升效果,为高负荷小区的速率提升提供了后台参数优化的可行性建议。
简介:Inthispaper,thedesignofsignalconstellationsparametersisstudiedforDifferentialUnitarySpace-TimeModulation(DUSTM)basedonthedesigncriterionofmaximizingthediversityproduct.Further,nonintegersearchingmethodforthesignalconstellationparametersdesignisproposedinordertogetbettercodes.ExperimentalresultsshowthatunderthedifferentDopplerspreadanddatatransmissionrate,theproposeddesignperformsbetterthanthepreviousdesignusingintegerparametersinMultipleInputMultipleOutputOrthogonalFrequencyDivisionMultiplexing(MIMO-OFDM)systemoverfrequency-selectivefadingchannels.
简介:本论文中讨论了如何在内部底层逻辑电路和接口电路的限制下,使手持设备达到高速运行、精确传输的要求.通过BDC(MultipathDelayCommutator)时序方式,对输入数据、输出数据以及数据的位倒序存取提出一种单通道的时序方式,在满足存储器可行的全速读取时序内,加快傅里叶算法的运算速度.利用Radix-4的时间抽取FFT算法,通过Verilog编程软件以及XilinxISE开发板,实现算法的仿真.实验结果表明对于90纳米内的CMOS集成电路来说,该算法能够高效的完成64点FFT,从而嵌入到WiMAX信道标准中.
简介:摘要本文通过对装车楼系统洒水除尘进行改造,为系统增加了水箱,就地水车上水点,增加了空压机的远程操作功能,提高了洒水除尘系统的适用性,同时,增加了定量仓、缓冲仓冲洗箱、以及司机室玻璃冲水功能,为系统增加了辅助功能。