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Aserialoutshiftregister串行输出移位寄存器aserial-inshiftregister串行输入移位寄存器AMPS先进移动电话业务Analogtodigitalconverter数模转换器applicationspecificintegratedcircuit(ASIC)专业集点电路automaticFrequencycontrol(AFC)自动频率控制器bipolar-junctiontransistor（BJT)双极性晶体管CCI同信道干扰CDMA码分多址Clockpulse时钟脉冲Closed-loopgain闭环增益DCtransduceramplifier直流传感放大器DOS服务拒绝DPSK差分移位键控DQPSK回相移位键控DSP数字信号处理errorrate误码率FAT文件列表FDMA频分多址field-effecttransistor(FET)场效应晶体管Field-programmablegatearrays(FPGA)现场可编写门阵列FIR有限脉冲响应Gate-levelnetlist门极网表GSM欧洲数字系统GUI图形用户接口hardwaredescriptionlanguage(HDL)计算机硬件描述语言HybridTDMA混合时分复用IDS入侵检测IIR无限脉冲响应ISDN综合数字业务网ISI(Inter-symbolinterference)码间干扰JKflip-flopsJK触发器LAN局域网LEO低地球轨道losslessdatacompression无损数据压缩lossydatacompression有损数据压缩MAC媒体接入控制mental-oxidesemiconductor(MOS)金属氧化物半导体MTSO移动交换机构noisy-channelcodingtheorem噪信道编码理论OFDM正交平分OOA面向对象分析OOD面向对象设计OOPL面向对象程序设计语言Operationalamplifiers运算放大器PAPTR高峰值平均功率比pass-band通带PDM脉冲宽度调制Perbit/sec每秒比特数Phaselockloop(PLL)锁相环rate-distortiontheory率失真理论RFcommunication射频通信ripplecounters波纹计数器RS触发器RTL（registertransferlevel)寄存转换极SAN存储区域网络SFN单频网sign-to-noiseratio信噪比source-channelseparationtheorems信源分离理论System-on-chip(SOC)片上系统Tflip-flopsT触发器throughput吞吐量time-divisionmultiplexing时分多路TMDA时分多址UMTS移动通信系统Uncommittedlogicarray(ULA)同化逻辑阵列VISI超大规模集成芯片voltage-controlledoscillator(VCO)压控振荡器WDM波分复用Awirecarryingacurrentlooksexactlythesameandweighsexactlythesameasitdoeswhenitisnotcarryingacurrent.一根带电的导线其外表与重量都与不带电导线完全一样。Afibermayeitherbesingle-modeormultimode,dictatedbythespecificdesignandthewavelengthofthelightpropagatinginthefiber.一根光纤根据其设计和在其中传播的光的波长，可以是单模的也可以是多模的。Aninterleaverinessencescramblesthetimeorderofthebitsaccordingtoanalgorithmknownbythereceiver.交织器实质上根据接收端已知的某种算法打乱比特位的时间顺序。Achannelisadivisioninatransmissionmediumsothatitcanbeusedtosendmultiplestreamsofinformation.信道在传输媒介中分隔区域，以用于使传输媒介传送多个信息流。Aswavelengthsdecreasetoapproachthesizeofcircuitcomponents,circuitelementsarenolongerlumped,andleadscanactasreflectivecomponentsand/orantennasandlumpedelementsaselectromagneticresonators.随着波长减小到接近于电路元件的尺寸，电路单元就不再是集总的，导线可起到反射元件以及（或）天线的作用，集总单元则成为电磁谐振器。Afiltermayalsobedescribedasadifferenceequation,acollectionofzeroesandpolesor,ifitisanFIRfilter,animpulseresponseorstepresponse.7滤波器也可以用差分方程或一组零极点表示，对于FIR滤波器还可以用冲击响应或阶跃响应表示。Communicationisthetransmissionofinformationfromonepointtoanother.Thistransmissionrequirestheabilitytovarysignalswithtimeinamannerwhichisunpredictabletothereceiver.通信就是信息从一点传送到另一点。这种传送要求信号随时间发生的变化不能在接收端预测Thereverselinkisnotorthogonal,resultinginsignificantinter-userinterference.Forthisreasonthereversechannelsetsthecapacityofthesystem.反向连接是非正交的，导致用户间的严重干扰。由于这一原因，反向信道限制了系统的容量。Theoutputofoneflip-flopistheinputtothenext;thestatechangesconsequently“ripplethrough”theflip-flops,requiringatimeproportionaltothelengthofthecounter.一个触发器输出是下一个的输入，因而状态变化以波动形式通过各触发器，所需时间与计数器长度成正比。Thetaskofaphaselockreceiveristoreproducetheoriginalsignalwhileremovingasmuchofthenoiseaspossible锁相接收机的作用是重建原信号而尽可能地去除噪声。Theinputdatatobetransmittedisbufferedoverthepreviousframeandbursttransmittedatahigherrateduringthetimeslotforthechannel.待发送的输入数据在前一帧期间被缓存，在分配给该信道的时隙中以较高速率爆发式发送出去Themainfunctionofthereceiveristoextracttheinputmessagesignalfromthedegradedversionofthetransmittedsignalcomingfromthechannel.接收器的主要功能是从由信道传输来的退化了的信号中提取出输入消息Sincetheverybeginning,communicationssystemshaveconsistedofthreemajorparts,namely,theequipment,themedium,andtheprotocol.Itisstillthecasetoday.However,thecloselinkoftelecommunicationswiththecomputertechnologyhasbroughtabouttremendouschangesincommunications,fromtheconcepts,tothecontentsandthemethods.从一开始通信系统就由设备、媒介和协议三个要素组成。至今依然如此。然而电信与计算机技术的紧密联系使得通信从概念到内容和手段都发生了重大的变化Theprocessgainofasystemindicatesthegainorsignaltonoiseimprovementexhibitedbyaspreadspectrumsystembythenatureofthespreadinganddespreadingprocess.系统处理增益是指扩频系统通过扩频和反扩频的性质所表现出来的增益或信噪比的提高Theideaisthat,ifthecentercellusesafrequencyf1forcommunication,thesixneighboringcellscannotutilizethisfrequencybutthecellsbeyondtheimmediateneighborsmay.频率重用概念是：如果位于中央的蜂窝使用频率f1进行通信，那么与其相邻的6个蜂窝就不能使用这个频率，但外面不直接相邻的蜂窝可再次使用这个频率Theconceptofavailabilitymeansthattheinformation,thecomputingsystemsusedtoprocesstheinformation,andthesecuritycontrolsusedtoprotecttheinformationareallavailableandfunctioningcorrectlywhentheinformationisneeded.信息可用性是指当需要某一信息时，信息本身、用来处理信息的计算机、保护信息的安全控制都处于有效可用的状态，并且功能正常。TheswithingoftheMCUiscommonlyachievedbyvoiceactivationsothatthesitewheretheaudioisactiveistransmittingtoallreceivingsites.MCU的切换通常是用语音驱动，这样有语音出现的的节点就向所有接收点发送信息。e.Theobjectiveistobeabletodesignacircuitfromthebasisofthepublisheddata,andknowthatitwillfunctionaspredictedwhentheprototypeisconstructed.能按公布的数据设计电路，并确认构建的样机具有预计的功能Whentheloopislocked,thecontrolvoltageissuchthatthefrequencyoftheVCOisexactlyequaltotheaveragefrequencyoftheinputsignal当锁相环处于锁定状态时，控制电压使压控振荡器的频率正好等于输入信号频率的平均值。Roughlyspeaking,thetransistorcanbelikenedtoanelectronicallycontrolledvalvewherebyenergyappliedtooneconnectionofthevalveenablesenergytoflowbetweentwootherconnections.粗略地说，晶体管好似一种电子控制阀，由此加在阀一端的能量可以使能量在另外两个连接端之间流动Gatearraydesignisamanufacturingmethodinwhic