Abstract: Multipactorisoneofthemostimportantfailure   effectsforthespacebornemicrowavecomponents.Withtherapiddevelopmentofwidebandcommunication satellitesystems,themulticarriermultipactor(MM) ispaidmoreandmoreattentions.Whilethedesigncriterionwithmicrowavecomponentsforsingle carrierRFsignalisexplicit,itiscontroversialformulticarriermultipactor.Amethodtodetermine equivalentpowerforthesingleeventmulticarriermultipactorusingthemodifieddifferentialevol utionalgorithmwaspresentedtoovercomethedisadvantagesoftheconventionalempiricalformula.The powerpropertiesforthemulticarriersynthesissignalswereanalyzed,andtheenergyin20electrontransittimewasgloballyoptimized.Ineachoptimization,quadratic  interpolationwasusedtofind thelocaloptimum,thentheglobaloptimumwasobtainedbyusingthemodifiedDifferentialEvolutio nalgorithm.Itistheworstcaseforallkindsofconfigurationsandtheoptimalaveragepowercanbeusedfortheequivalentpowerinthewidebandcomponentdesign.Theproposedmethodisdemonst ratedwiththeuniformamplitudeandequallyspacedfrequencies.Theproposedapproachisalsoable toprovidereasonableequivalentpowerformulticarriersignalswithnonuniformamplitudesorthe unequallyspacedfrequencies.

Key words: differentialevolutionalgorithm；singleeventmulticarriermultipactor； equivalentpower；microwavecomponents  , equivalentpower；microwavecomponents