简介:BlockmatchinghasbeenusedformotionestimationandmotioncompensationintheAu-dioandVideoStandard(AVS)foryears.Whilehavinganacceptableperformanceindescribingmo-tionbetweenframes,itrequiresquiteafewbitstorepresentthemotionvectors.Incertaincircum-stances,theuseofglobalmotionestimationandcompensationwouldperformequallywellorevenbetterthantheblockmatchingintermsofmotionaccuracy,whileitresultsinthecodingofglobalmotionmodelparameters.Inthisletter,wemodifyanAVScoderbyadding(1)sixglobalmotionmodelparameterstotheframeheader,and(2)modeselectionamongINTRA,SKIP,INTER-16×16,INTER-16×8,INTER-8×16,INTER-8×8,andGlobalMotionCompensation(GMC)modesbyLa-grangeoptimalrate-distortioncriteria.Simulationresultsdemonstratethatover0.1dBimprovementinPSNRisobtainedcomparedtotheAVScoderforanaveragecodedP-framewiththesamebit-rate.
简介:文章以LTCC基P波段90°功分器的设计和制作为例,从无源设计仿真和LTCC工艺阐述了P波段功分器的研制过程。选用了承受功率大、尺寸相对较小的宽边耦合器结构。设计的宽边耦合器采用多层结构,有利于发挥LTCC基板多层、高集成度等优点。其电路物理模型为Broadside-coupledsymmetricstripline(BCL),采用的介质为LTCC,介电常数为5.9,每层介质厚度为0.1mm,导体采用Ag浆。在实物制作过程中,TOP层和Bottom层是采用灌银通孔实现的。最终测试结果与仿真结果吻合较好,在225MHz~400MHz频段内隔离23dB,插损0.5dB,驻波1.1,相平衡度±2.5,功率250W.
简介:Ap-typeAlAs(70.2nm)/16.5period[GaAs(3nm)/AlAs(0.7nm)]semiconductor/superlaticedistributedBraggreflector(DBR)hasbeengrownonn+-GaAs(100)substratebyV80Hmolecularbeamepitaxysystem.Experimentalreflectionspectrumshowsthatitscentralwavelengthis820nm,withthepeakreflectivityfor10-pairDBRofashighas96%,andthereflectionbandwidthofaswideas90nm.Weformeda20×20μm2squaremesatomeasuretheseriesresistanceusingwetchemicaletching.Fromthemeasurementresult,theseriesresistanceofabout50Ωisobtainedatamoderatedoping(3×1018cm-3).Finally,thedependenceoftheresistanceoftheDBRonthetemperatureisanalyzed.Fromtheexperimentalresult,itisfoundthatthemechanismofthelowseriesresistanceofthiskindofDBRmayincreasethetunnelingcurrentinthesemiconductor/superlatticemirrorstructure,whichwillresultinadecreaseinseriesresistance.
简介:
简介:接口特征在薄电影设备的性能上拥有很重要的影响。ITO/PTCDA/p-Si薄电影设备与真空蒸发和噼啪声免职方法被建立。ITO/PTCDA/p-Si的表面和接口电子国家被X光检查光电子光谱学(XPS)和氩离子横梁调查蚀刻技术。结果在ITO/PTCDA/p-Si,不是仅仅ITO/PTCDA-Si的接口显示那而且PDCDA-Si能生产散开。而且,每个原子的XPS系列显得化学移动,和Ols和Ols的化学移动是更显著的。CLC数字O484文件代码A工程被中国的国家自然科学基础支持(不同意60076023)