简介:UltraWideBand(UWB)transmissionsareattractiveforlowpower,basebandasynchronousmultipleaccessandpeer-to-peerwirelesscommunications.MultipleInputMultipleOutput(MIMO)technologyisusefulincombatingagainstmultipathandatthesametimeimprovessystemperformancebyusingmultielementantennasatbothtransmitterandreceiver.ThisletterproposesatimehoppingM-aryUWBsystemsusingV-BLASTalgorithm,andpowercontrolisconsideredforbetterperformance.Simulationsareprovidedtocompareperformancewithdifferentantennas.
简介:AnexperimentalwayforthethermalcharacterizationofsemiconductorlasersbasedonI-Vmethodunderpulsedrivingconditionshasbeendeveloped,withwhichthethermalcharacteristicsofstraincompensated1.3μmInAsP/InGaAsPridgewaveguideMQWlaserchipshavebeeninvestigated.Theresultsshowthat,bymeasuringandanalyzingtheI-Vcharacteristicsunderappropriatepulsedrivingconditionsatdifferentheatsinktemperatures,thethermalresistanceofthelaserdiodescouldbeeasilydeduced.Thedrivingcurrentandjunctionvoltagewaveformsofthelaserchipsunderdifferentpulsedrivingconditionsarealsodiscussed.