简介:Thispaperstudiesthetrackingperformanceofthesingle-inputsingle-output(SISO),finitedimensional,linearandtime-invariant(LTI)systemoveranadditivewhiteGaussiannoise(AWGN)channelwithfinitecontrolenergyandchannelinputenergyconstraint.Anewperformanceindexisproposedwhichisminimizedoverallstabilizingtwo-degree-of-freedomcontrollers.Theexplicitexpressionsofthelowerboundofthetrackingperformanceandtheminimumofsignal-to-noiserequiredareobtained.Theresultsshowthatthelowerboundiscorrelatedtotheunstablepole,nonminimumphasezeroandthechannelscalingfactor.Finally,oneexampleisgiventovalidatetheconclusionsbyadoptingthespecialinner-outerfactorization.
简介:Withtheobjectiveoftakingfulluseofchannelresource,weproposedtwoutilitybaseddynamicsubcarrierallocation(DSA)algorithmsforthesinglecarrierfrequencydivisionmultipleaccess(SC-FDMA)system,whicharetheproportionalfairfrugalityconstrained(PF-FC)algorithmandtheweightedproportionalfairfrugalityconstrained(WPF-FC)algorithm.Thetwoproposedalgorithmsaredesignedunderthefrugalityconstraint(FC)controlconsiderationsoastoavoidserviceratewasteandimprovethespectrumefficiency.Moreover,thequeuingbuffermodelinthispaperisestablishedonafinitesizestructureratherthanthetraditionalinfinitequeuingmanner,whichismoreconsistentwiththepracticaltransmissioncondition.Simulationresultsindicatethatthetwoproposedalgorithmscanbothachievesignificantlybettersystemrate-sumcapacityandqualityofservice(QoS)performancethantheirprimaryalgorithms,andaremoreapplicablefortheheterogeneoustraffic.