简介：文章引入了(L,M)-fuzzy层次拓扑空间范畴,讨论了它与L-fuzzy层次拓扑空间范畴的关系,证明了(L,M)-fuzzy层次拓扑空间范畴、(L,M)-fuzzy层次邻域空间范畴、(L,M)-fuzzy层次闭包空间范畴以及(L,M)-fuzzy层次内部空间范畴等均是等价的。

简介：Pulse-pairs(PP)generatedbydistancemeasuringequipment(DME)causesevereinterferencetotheL-banddigitalaeronauticalcommunicationsystems.UnlikepreviousworksthatmainlyimprovedreceiverstructureformitigatingtheDMEinterference,thispaperproposesanovelandpracticaltimedomainPPmitigationmethodwithoutchangingtheexistingreceiverstructure.Ourmethodiscomposedofthreepartsandutilizesaspecificproperty,i.e.,arelativelyfixedwaveformofDMEPP.First,thecomplex-valuedwaveformofPPisautomaticallydetectedthroughaniterativeweightedaveragemethod.Then,onthebasisofthedetectedPPwaveform,eachPPisreconstructedaccordingtoitsamplitude,position,andinitialphase,whichareestimatedthroughasparserepresentationalgorithm.Finally,thereconstructedPPsaresubtractedfromthecontaminatedsignal.Numericalexperimentsshowthatcomparedwithrecentlypublishedmethodsthebiterrorrateobtainedbyourmethodisapproximately5dBbetter,whilethecomplexityismaintainedatthesamelevel.