简介:Thispaperproposesanovelschemebasedonminimumdelayattheedges(MDE)foropticalburstswitching(OBS)networks.ThisschemeisdesignedtoovercomethelongdelayattheedgenodesofOBSnetworks.TheMDEschemefeaturessimultaneousburstassembly,channelscheduling,andpre-transmissionofcontrolpacket.Italsofeaturesestimatedsetupandexplicitrelease(ESXR)signalingprotocol.TheMDEschemecanminimizethedelayattheedgenodesfordatapackets,andimprovetheend-to-endlatencyperformanceforOBSnetworks.Inaddition,comparingwiththeconventionalscheme,theperformancesoftheMDEschemeareanalyzedinthispaper.
简介:ElectronleakagestillneedstobesolvedforInGaN-basedblue-violetlaserdiodes(LDs),despitethepresenceoftheelectronblockinglayer(EBL).Toreducefurtherelectronleakage,anewstructureofInGaN-basedLDswithanInGaNinterlayerbetweentheEBLandp-typewaveguidelayerisdesigned.TheopticalandelectricalcharacteristicsoftheseLDsaresimulated,anditisfoundthattheadjustedenergybandprofileinthenewstructurecanimprovecarrierinjectionandenhancetheeffectiveenergybarrieragainstelectronleakagewhentheIncompositionoftheInGaNinterlayerisproperlychosen.Asaresult,thedeviceperformancesoftheLDsareimproved.
简介:Atwo-dimensional(2D)opticaltrue-timedelay(TTD)beam-formingsystemusingacompactfibergratingprism(FGP)foraplanarphasedarrayantenna(PAA)isproposed.Theopticalbeam-formingsystemmainlyconsistsofaTTDunitbasedonthesamecompactFGP,onetunablelaserforelevationbeamsteering,andacontrolledwavelengthconverterforazimuthbeamsteering.AplanarPAAusingsuch2DopticalTTDunithasadvantagessuchascompactness,lowbandwidthrequirementfortunablelasersources,andpotentialforlarge-scalesystemimplementations.Theproof-of-conceptexperimentresultsdemonstratethefeasibilityoftheproposedscheme.
简介:Wepresentanovelcoherenttransceiverforopticaldifferentialphase-shiftkeying/differentialquadraturephase-shiftkeying(DPSK/DQPSK)signalsbasedonheterodynedetectionandelectricaldelayinterferometer.Asimulationframeworkisprovidedtopredictatheoreticalsensitivitylevelforthereportedscheme.Highsensitivityof-45.18dBmisachievedfor2.5-Gb/sreturn-to-zero(RZ)-DPSKsignal,andhighsensitivitiesof-36.83dBm(Itributary)and-35.90dBm(Qtributary)areobservedfor2.5-GBaud/sRZ-DQPSKsignalinback-to-backconfiguration.Transmissionforbothsignalsover100kmisalsoinvestigated.Experimentalresultsarediscussedandanalyzed.