简介:不知不觉中,明基的Joybook已经更新到了第二代。在明基BenQ品牌发布两周年之际,明基推出了全新系列笔记本,除了新型号Joybook6000以外,还有Joybook8000的升级版Joybook8100,Joybook5000系列的升级版Joybook5100。这次我们给大家介绍的就是Joybook5100.Joybook5100在Joybook5000基础上做了不少改进,Joybook5100整体给人感觉没有Joybook5000那么跳,不像Joybook5000那样曲线玲珑,Joybook5100的线条比较平滑,走的是中性化路线,这样更易让大众接受。
简介:Inthispaper,onlynarrow-senseprimitiveBCHcodesoverGF(q)areconsidered.Aformula,thatcanbeusedinmanycases,isfirstpresentedforcomputingthedimensionofBCHcodes.ItimprovestheresultgivenbyMacWilliamsandSloanein1977.AnewmethodforfindingthedimensionofalltypesofBCHcodesisproposed.Insecondpart,itisprovedthattheBCHboundistheleaderofsomecyclotomiccoset,andweguessthattheminimumdistanceforanyBCHcodeisalsotheleaderofsomecyclotomiccoset.
简介:Thispaperpresentsthelowerboundsandupperboundsforthemeanvalueandvarianceofdistancedistributionofnon-linearcodesinGF(q).Bypresentingseveralexamples,itisshownthattheseboundscouldbeachieved.
简介:ThroughusingbothCr4+:YAGandGaAssaturableabsorbers,adiode-pumpeddoublepassivelyQ-switchedNd:GdVO4laserisrealizedandcomparedwithasinglepassivelyQ-switchedlaser.Thislasercangeneratesymmetricpulsetemporalprofilesandshorterpulses.Alaserpulsewidthof17nshasbeenachievedwiththeincidentpumppowerof8.5W.
简介:All-opticalregeneratorscanbeusedtosuppressamplifiedspontaneousemission(ASE)noiseintroducedbycascadederbiumdopedfiberamplifiers(EDFAs)inopticalfibercommunicationsystemsandleadtotheimprovementofopticalreceiversensitivity.ByintroducingtheQ-factortransferfunction(QTF),weevaluatetheQ-factorperformanceofdegeneratefour-wavemixing(DFWM)regeneratorswithclockpumpandrevealthedifferencesbetweentheoptimalinputpowersdeterminedfromthestaticanddynamicpowertranferfunction(PTF)andtheQTFcurves.Oursimulationshowsthattheclock-pumpregneratoriscapableofimprovingtheQ-facorandreceiversensitivityfor40Gbit/sASE-degradedreturn-to-zeroon-offkeying(RZ-OOK)signalby2.58dBand4.2dB,respectively.
简介:Recently,alotofdigitalsubscriberloopsystems(DSL)andhighratedigitalsubscriberloopsystems(HDSL)havebeendeployedindigitalsubscriberaccessnetworks.DataechocancellerisextensivelyusedintheDSLandHDSLsystemstorealizefullduplextransmissionontwistedcable.Insuchsystems,2B1Qlinecodeisadopted.Therefore,symbolrateisdecreasedanddigitaltransmissionsystemsgetlongerreach.Inthispaper,aperformanceevaluationmethodoftheechocancellerisproposedbasedonanautocorrelationmatrixof2B1Qlinecode.Usingthismethod,theformulaofratioofdatasignaltoechoresidualsignalisobtained.Accordingtotheformula,theratioofdatasignaltoechonoisedependsonFIRfiltertap,convergencefactor,adaptivealgorithmandthecorrelationmatrixofthelinecode.Computersimulationiscarriedouttoverifytheoreticalanalysis.Thesimulationresultscoincidedwiththetheoreticalformulaintheprocessestimatingtheratioofsignaltonoise.
简介:WeproposeanddemonstrateexperimentallyamultimodeoscillationQ-switchederbium-dopedfiberlaserwithafew-modefibercavity.ThedifferentcouplingprocessesofreflectionpeaksoffiberBragggratings(FBGs)whichactascavitymirrorsallowthedifferentoscillatingstates.Weobtainmicrosecondlightpulseoutputstateswhoseoscillationandoutputbeamshavedifferentmodecompositions,includinghighordermode.Suchastructureenablesthehighordermodeoscillationinthewholecavitywithanall-fiberstructure,whichhaspotentialapplicationsinmode-divisionmultiplexedsystemsandresearchofmultimodenonlineareffect.