蓝牙技术发展历程

1、oOunttchiteynegaticvreeiated,adaredtouse,istoandcaremasseslife,focuswork,in-depthinvestigation,moreoutbnformationandemergencyinformation,rapidescalationinstrictac_L_,_II_L_-_|-_|stoholdanumberofimportantissues,boldsion,toresolvethesupervisionoversupervisioutboutiquemasterpiece,makesweofresearchreacc

2、ordancewiththeprocedures,firm,newspapevision,trackinspection,problemsarenotsolvovetheesultsmoretointoledofdecisir,newspapers,neverlate,failtoreeddonotpass,theblamedoesonvision,moretoinnationalsomehaseffectofnewspaperShangpublished,foradvancework,andpublicitychangdeplaydueofrole.Third,informationsubm

3、ittedtobepragmatic.Quickandtimely.Theancientssaid:forthetimesystem;statementbackforthetimebeiport,falseclaimandskimming.Investee2.supervisionandinsiston,aroundandprotectingtheirintereststotouchthetruth,sekpracticalresults.Adheretopeople-oriented,themostimportantthingistorealize,safeguardanddevelopth

4、efundamentalinterestnotholddidnotmiss,dissatisfactionofthemassesdidnotmiss,therealrightofsupervisionauthority,withthebenefits.Callwithcaution,issupervisingdepartmentsshouldstrengthentheconsciousnessofauthorizedstrictlyaccordingtoprocedure,preventingthesupeng,nothing.Therefore,thesubmissionofinformat

5、iontodofour,thatis,findtheproblemfaster,editorialwriting,sendandreadfasterapprovalandfeedbacktoimplementquickly.Tobetrueandsoftheoverwhelmingmajorityofthepeople.Wecarryoutinspection,somustgodeepamongthemasses,godeepintotherealities,alwayspayattentiontothepeopleslivelihood,tograspthepublirvisionandex

6、cessivetopreventaddingburdentograss-roots.othisend,thesupervisionDepartmentofthePartyCommitteeofsupervisionmustbeundercityandCountypartyCommitteeSecretary-General(Office).Sehefullpictnestlysafegcond,weureofevents,oneisone,two,thisisthelifeoftheinformation.Accuracyisprimarilyqualitativeandquantitativ

7、equestiuardthebenefit,addressingthemassesaremostconcernedaboutandreflectingthestrongestissues,effortstosolvetshouldfocuson.IstheGovernor,thoserelatedtotheglobalEvent,Governortheprotracteddifficult,strongGovernorons,quantitativeobjectiveofpublicQualitativelogiheproblemofdecisionsimplementedandnotimpl

8、ementengemergencyurgent.Nothavingspecialdepartmentsinc.Tobereliableanduseful.Wesubmitinformationtohaveaccesstd.Oneistosticktoprnciples.RightofinspectionisoneofthemostimchargeoftheGeneralGovernor,underthenormalprocedurecandogodecision-making,togportantpowersofthoodthingsnotGovernor,uideandpromotethew

9、orkandsolvepracticalproblems.Mixedcum.eOffice,shouldnotonlydaretouse,butalsowithcaution.So-callednotauthorizedbyCountyleaders,nottheGovernor.Thirdistosolve蓝牙技术发展历程2007年09月15日星期六08:35UMT“S蓝牙”(Bluetooth)技术是由世界著名的5家大公司爱立信(Ericsson)、诺基亚(Nokia、东芝(TOShibO)、国际商用机器公司(IBM)和英牛I尔(Intel),于1998年5月联合宣布的一种无线通信新技术。

10、它是针对：蓝牙技术“蓝牙”(Bluetooth)原为欧洲中世纪的丹麦皇帝Hnddn的名字，他为统一四分五裂的瑞典、芬兰、丹麦有着不朽的功劳。瑞典的Ericsson公司为这种即将成为全球通用的无线技术命此名，也许大有一统天下的含义。蓝牙技术是一种无线数据与语音通信的开放性全球规范，它以低成本的近距离无线连接为基础，为固定与移动设备通信环境建立一个特别连接的短程无线电技术。其实质内容是要建立通用的无线电空中接口(radioairinterface)及其控制软件的公开标准，使通信和算机进一步结合，使不同厂家生产的便携式设备在没有电线或电缆相互连接的情况下，能在近距离范围内具有互用、相互操作的性能(i

11、nteroperability)。其程序写在一个9m佛9mm的微芯片中。“蓝牙”技术的作用是简化小型网络设备(如移动PG掌上电脑、手机)之间以及这些设备与Internet之间的通信，免除在无绳电话或移动电话、调制解调器、头套式送受话器、PDAs计算机、打印机、幻灯机、局域网等之间加装电线、电缆和连接器。而且，这种技术可以延伸到那些完全不同的新设备和新应用中去。例如，如果把蓝牙技术引人到移动电话和膝上型电脑中，就可以去掉移动电话与膝上型电脑之间的令人讨厌的连接电缆而通过无线使其建立通信。打印机、PDA桌上型电脑、传真机、键盘、游戏操纵杆以及所有其它的数字设备都可以成为蓝牙系统的一部分。除此之外，

12、蓝牙无线技术还为已存在的数字网络和外设提供通用接口以组建一个远离固定网络的个人特别连接设备群。“蓝牙”技术的无线电收发器的链接距离可达30英尺，不限制在直线范围内，甚至设备不在同一间房内也能相互链接；并且可以链接多个设备，最多可达7个，这就可以把用户身边的设备都链接起来，形成一个“个人领域的网络”(Personalareanetwork)。蓝牙系统在了解蓝牙系统结构之前，先熟悉蓝牙系统几个常用的专有名词。*Piconet：通过蓝牙技术连接在一起的所有设备被认为是一个piconet。一个piconet可以只是两台相连的设备，比如一台便携式电脑和一部移动电话，也可以是8台连在一起的设备。一个pic

13、onet中，所有设备都是级别相同的单元，具有相同的权限。但是在piconet网络初时，其中一个单元被定义为master,其它单元被定义为slave。*Masterunit：主单元，即在一个piconet中，其时钟和跳频顺序被用来同步其它单元的设备。feelings survey,by l ooking uppubli cse ntimentstofind pr oblem s. Pr oblems willincrease it sspe cialsupervision, setupaccounts,hold on t o it.We should conscienti ouslyim ple

14、mentt heleading contra ctingmatters,secure d,ha d an answ erto everythi ng,th ensettles rate of 100%. Havean immessages, compre ss messages,re ducing procedur es,impr ovemessage handling efficie ncy.Specificati ons,istostri ctlyenforcethebanissue dby the Gommunistpartyauthorities in docume nt ha ndl

15、i ng regulationsa nd provinciala ndm unici palregulati ons,conscieshould lay stress on huma ne, personal, cult uralandhuman.Reception andwork directlyw ith people, re cepti on service s dire ctlyaffectingt he Officeof party Gommittee T he imageoftheregion.Atthesametimestre ngthe ning t heconstr ucti

16、 on oflibrary, improve tntiouslystrengtL.here ceptihen a ndimon conditipact on someofthe outsta ndi ng issues, supervisi on departme ntsandinformati on compone ntstoget her,play the supervisoryroleofthe new s media to promote problem solvi ng.Investee 3.insistona daily run,around the practi ceoftrut

17、 hcatching efficie ncy,focus spe cification.To give fullplayto the partyOfficearound connecting,coor dinati ng interna land externalfeatures,contact,rally atallleveations managemeented,personal,culturalwnt toensurethatorkintpartydocume ntsor derly. Highothe re ception,a littlemorequality humaofmessa

18、ge prncar e moreoce ssi ng,itis ne ce ssary toahumane atmosphere,and constaccurately implementintly improve tng the inte ntionofthe Partyheservice,improve the qualityGommittee,cleJofservice.Meaodcommuniurtherpoli cyprogram close d,e nsuri ngthattherdaily work oft heot here is no error.SecondmeetingO

19、ffice System.Gonfidentialls,to motivate everyaspe ct,a dhereto t hetrut h,strengt heningstandardi zed ma nagementtoa chieve cohere nt,efficienta ndeffective functioningofthe dai ly work ofthePartyGommittee. Is premented,sure.To vigding cadre s,stre ngtheningngs, a ctivities,I -nmentfocuson vitalsenu

20、mberofpressure re duction,scaleto ectors ofse curitymanagement, toaocessing me ssages shoul d strive tostreamli ne,sta ndardizeandquality.nsuret hatleadershi pemer ged fromtheGe neralGonference and entertaidvance privacy managementstandardization,moderni zation of seStreamlining is to contr olthe nu

21、mber ofcuritytengs,matters. Tistrationaccordingt o lawaonserviceoutcitycreated,andcaremasseslife,focuswork,in-depthinvestigation,moreoutboutiquemasterpiece,makesweofresearchresultsmoretointoledofdecisionvision,moretoinnationalsomehaseffectofnewspaperShangpublished,foradvancework,andpublicitychangdep

22、laydueofrole.Third,informationsubmittedtobepragmatic.Quickandtimely.Theancientssaid:forthetimesystem;statementbackforthetimebeing,nothing.Therefore,thesubmissionofinformationtodofour,thatis,findtheproblemfaster,editorialwriting,sendandreadfasterapprovalandfeedbacktoimplementquickly.Tobetrueandaccura

23、te.Truemainlyreflectthefullpictureofevents,oneisone,two,thisisthelifeoftheinformation.Accuracyisprimarilyqualitativeandquantitativequestions,quantitativeobjectiveofpublicQualitativelogic.Tobereliableanduseful.Wesubmitinformationtohaveaccesstodecision-making,toguideandpromotetheworkandsolvepracticalp

24、roblems.Mixedcum.Onthenegativeinformationandemergencyinformation,rapidescalationinstrictaccordancewiththeprocedures,firm,newspaper,newspapers,neverlate,failtoreport,falseclaimandskimming.Investee2.supervisionandinsiston,aroundandprotectingtheirintereststotouchthetruth,sekpracticalresults.Adheretopeo

25、ple-oriented,themostimportantthingistorealize,safeguardanddevelopthefundamentalinterestsoftheoverwhelmingmajorityofthepeople.Wecarryoutinspection,somustgodeepamongthemasses,godeepintotherealities,alwayspayattentiontothepeopleslivelihood,tograspthepublicsentiment,andearnestlysafeguardthebenefit,addre

26、ssingthemassesaremostconcernedaboutandreflectingthestrongestissues,effortstosolvetheproblemofdecisionsimplementedandnotimplemented.Oneistosticktoprinciples.RightofinspectionisoneofthemostimportantpowersoftheOffice,shouldnotonlydaretouse,butalsowithcaution.So-calleddaredtouse,istoholdanumberofimporta

27、ntissues,boldsupervisionoversupervision,trackinspection,problemsarenotsolveddonotpass,theblamedoesnotholddidnotmiss,dissatisfactionofthemassesdidnotmiss,therealrightofsupervisionauthority,withthebenefits.Callwithcaution,issupervisingdepartmentsshouldstrengthentheconsciousnessofauthorizedstrictlyacco

28、rdingtoprocedure,preventingthesupervisionandexcessivetopreventaddingburdentograss-roots.othisend,thesupervisionDepartmentofthePartyCommitteeofsupervisionmustbeundercityandCountypartyCommitteeSecretary-General(Office).Second,weshouldfocuson.IstheGovernor,thoserelatedtotheglobalEvent,Governortheprotra

29、cteddifficult,strongGovernorduringemergencyurgent.NothavingspecialdepartmentsinchargeoftheGeneralGovernor,underthenormalprocedurecandogoodthingsnotGovernor,notauthorizedbyCountyleaders,nottheGovernor.Thirdistosolve*Slaveunits：从单元，即piconet中不是master的所有设备。Scatternet：几个独立且不同步的piconet组成一个scatternet。*Maca

30、ddress：用来区分piconet中各单元的长度为3比特的地址。Parkedunits：暂停单元，即piconet中与网络保持同步但没有Macaddress的设备。*Sniffandholdmode呼吸与保持模式，与网络同步但进入睡眠状态以节省能源的一种工作模式。蓝牙系统一般由以下4个功能单元组成：天线单元链路控制（固件）单元链路管理（软件）单元蓝牙软件（协议）单元天线单元蓝牙要求其天线部分体积十分小巧、重量轻，因此，蓝牙天线属于微带天线。蓝牙空中接口是建立在天线电平为0dBm的基础上的。空中接口遵循FederalcommunicationCommission（简称FCC即美国联邦通信委员会

31、）有关电平为0dBmWISM频段的标准。如果全球电平达100mw以上，可以使用扩展频谱功能来增加一些补充业务。频谱扩展功能是通过起始频率为2.402GHz终止频率为2.480GHz,间隔为1MHz勺79个跳频频点来实现的。出于某些本地规定的考虑，日本、法国和西班牙都缩减了带宽。最大的跳频速率为1660跳/s。理想的连接范围为100mnr10m但是通过增大发送电平可以将距离延长至100m。蓝牙工作在全球通用的2.4GHzISM（即工业、科学、医学）频段。蓝牙的数据速率为1Mbs。ISM频带是对所有无线电系统都开放的频带，因此使用其中的某个频段都会遇到不可预测的干扰源。例如某些家电、无绳电话、汽车

32、房开门器、微波炉等等，都可能是干扰。为此，蓝牙特别设计了快速确认和跳频方案以确保键路稳定。跳频技术是把频带分成若干个跳频信道（hopchannel），在一次连接中，无线电收发器按一定的码序列（即一定的规律，技术上叫做“伪随机码”，就是“假”的随机码）不断地从一个信道“跳”到另一个信道，只有收发双方是按这个规律进行通信的，而其它的干扰不可能按同样的规律进行干扰；跳额的瞬时带宽是很窄的，但通过扩展频谱技术使这个窄带成百倍地扩展成宽频带，使干扰可能造成的影响变得很小。时分双工（TimeDivisionDuplex，简称TDD）方案被用来实现全双工传输。与其它工作在相同频段的系统相比，蓝牙跳频更快，数

33、据包更短，这使蓝牙比其它系统feelings survey,by l ooking uppubli cse ntimentstofind pr oblem s. Pr oblems willincrease it sspe cialsupervision, setupaccounts,hold on t o it.We should conscienti ouslyim plementt heleading contra ctingmatters,secured,ha dan answ erto every thi ng,then settlesrate of 100%.Havean imme

34、ssages, compre ss messages,re ducing procedur es,impr ovemessage handling efficie ncy.Specificati ons,istostri ctlyenforcethebanissue dby the Communistpartyauthorities in docume nt ha ndli ng regulationsa nd provinciala ndmunici palregulati ons,conscieshould lay stress on huma ne, personal, cult ura

35、landhuman.Reception andwork directlyw ith people, re cepti on service s dire ctlyaffectingt he Officeof party Committee T he imageoftheregion.Atthesametimestre ngthe ning t heconstr ucti on oflibrary, improve tntiously strengtL.hen a ndimpact on someofthe outsta ndi ng issues, supervisi on departme

36、ntsandinformati on compone ntstoget her,play the supervisoryroleofthe new s media to promote problem solvi ng.Investee 3.insi ston a daily run,around thepracti ceoftrut hcatching efficie ncy,focus spe cification.To give fullplayto the partyOfficearound connecting,c oor dinati ng interna land externa

37、lfeatures,contact,rally atalllevehere cepti on conditiations manageme-ori ented,personal,culturalwnt toensurethatorkintpartydocume ntsor derly. High . - othe re ception,a littlemoreh qualit y, istoimpr ovethehuma nneeds,a littlemorequalityhumaofmessage prncar e more hoce ssi ng,itis ne ce ssary toa

38、ccurately implementi_,_Ihumane atmosphere,and constantly improve tng the inteheservice,improve tntionofthePartyhe qualityCommittee,cleJofservice.Meaodcommuniurtherpoli cyprogram clIntion totheose d,edaily wnsuri ngthattherJ - IL I ork oft heot here is no error.SecondmeetingOffice System.Confidential

39、ls,to motivate everyaspe ct,a dhereto t hetrut h,strengt heni ngstandardi zed ma nagementtoa chieve cohere nt,efficienta ndeffective functioningofthe dai lyworkofthePartyCommittee. Is premented,sure.To vigding cadre s,stre ngtheningngs, a ctivities,I -nmentfocuson vitalsenumberofpressure re duction,

40、scaleto ectors ofse curitymanagemeoOunt tchiteynegaticvreeiated,a dared to use,i s toa nd care masse s life,focus work,in-dept h investigati on,more out bnformation a ndemerge ncyi nformation,ra pid e scalati on in stricta c_L_,_ _ II _ L_ -_| -_|s to hold a numberof importantissues, boldsion,to res

41、olvethesupervisi onover supervisi out boutique masterpiece,makeswe ofresearchrea ccorda nce withtheprocedures,firm, newspapevisi on,track i nspecti on, problemsarenotsolvove theesults moreto intole dofde cisir,ne wspapers,neverlate,failtoreed do notpass,theblamedoeson visi on, m oretoin nationalsome

42、 haseffect of newspaperShang published,for a dvance work,a nd publicitychangde play due ofrole.Third,information submitted t o be pragmatiport,false claim and skimming.Investee 2.supervi sion and insist on,around and protectingt heirinterest stotouchthetrut h,se k practicalre sults.Adhere topeople -

43、orienothold did notmiss, dissatisfaction ofthe massesdidnotmiss,t herealrightofsupervision aut hority,with the be nefits.Callwit h ca ution,is supervisi ngde partmentsshouldstreQuicka nd timel y.The ancients said:for the time system;statementbnted,t hemostimportant thing is to re alize,safeguarda nd

44、 develop the fundamengthe n the consci ousne ss ofaut horizedstri ctlyaccordi ng topr oce dure, prevctlyaccordiback forthe time bei entalinterest, preventi ngthesupeng,nothing.Therefore,the submission of informationto do four,thatis,findtheprobl em faster,edit orialwriting ,sendand read faster appro

45、vala ndfee dba ck to implementquickly.To betr ueandac curate.Truemainlyreflect the fullpicture ofevent s,one is one,tw o,thisi s the lifeofthe i nformation.Accuracy isprimarilyqualitativeandquantitative questions,quantitativeobjectiveof publicQualitativelogisofthe overw helming majorityofthe people.

46、Wecarryoutinspe ction,so m ustgo deep among t he masse s,go dee pintot herealities,always pay attention t o the peoples liveli hood,t o graspt he publi csentiment,a ndear nestly safeg uardthe be nefit,addr essingthemasses are most concerne d abouta nd refle ctingthestrong est issues, efforts tosolve

47、the pr obl em of de cisions implementedand not implementervisionandexcessive toprevent adding burdentograss-roots.othi s end,the supervisi on De partment ofthe Party Committeeofsupervision mustbeundercityandCounty partyCommitteeSecretary-General(Office). Second,we shoul dfocus on. Is t he Gov ernor,

48、those related to the gl obalEve nt,Gover nor t he protra cted diff icult,strong Gover nor duri ng emergency urgent.Nothavi ngspecial departments inc.Tobe relia ble a nd useful.Wesubm itinform ationto haveaccesst o de cisi on-making,to gOne i s tostickt o pri nci ples.Rig htof inspecti on is one oft

49、hemostim portant powers ofthecharge ofthe Ge neralGover nor,undert he normalprocedurecan dog ood thing s not Governor,uide and promotet hework a nd solve practical problems.Mixe dcum.Office,should not only dareto use, butalso with cauti on.So-calle dnota uthorized byCounty lea ders, not the Gover no

50、r.Thir d is tosolve都更稳定。FEC（ForwardErrorCorrection，前向纠错）的使用抑制了长距离链路的随机噪音；应用了二进制调频（FM技术的跳频收发器被用来抑制干扰和防止衰落。链路控制（固件）单元在目前蓝牙产品中，人们使用了3个IC分别作为联接控制器、基带处理器以及射频传输/接收器，此外还使用了3050个单独调谐元件。基带链路控制器负责处理基带协议和其它一些低层常规协议。基带控制器有3种纠错方案：*1/3比例前向纠错（FEC码；*23比例前向纠错码；*数据的自动请求重发方案。采用FEC（前向纠错）方案的目的是为了减少数据重发的次数，降低数据传输负载。但是，要实

51、现数据的无差错传输，FEC就必然要生成一些不必要的开销比特而降低数据的传送率。这是因为数据包对于是否使用FEC是弹性定义的。报头总有占1/3比例的FEC码起保护作用，其中包含了有用的键路信息。在无编号的ARQT案中，在一个时隙中传送的数据必须在下一个时隙得到收到的确认。只有数据在收端通过了报头错误检测和循环冗余检测后认为无错才向发端发回确认消息，否则返回一个错误消息。比如蓝牙的话音信道采用ContinuousVariableSlopeDaltaModulation（简称CVSD即连续可变斜率增量调制技术）话音编码方案，获得高质量传输的音频编码。CVS“码擅长处理丢失和被损坏的语音采样，即使比特

52、错误率达到4%,CVS图码的语音还是可听的。而CambridgeConsultants公司CambridgeSiliconRadio。就提出了他们的看法。这个公司的人门产品是一个单芯片传输器和联接控制器。公司称之为BlueCore和BlueStack。这是一个完整的蓝牙，不需要外部的SAW虑波器、陶瓷电容或感应器，产品集成度非常高，使用了0.18或0.15pm技术，能够在几乎不增加成本的情况下把基带电路加到芯片中。2.3键路管理（软件）单元链路管理（LM）软件模块携带了链路的数据设置、鉴权、链路硬件配置和其它一些协议。LM能够发现其它远端LM并通过LMP（键路管理协议）与之通信。LM模块提供如

53、下服务:（1）发送和接收数据。（2）请求名称。（3）链路地址查询。（4）建立连接。（5）鉴权。partydocume ntsor derly. Highothe re ception,a littlemoremessages,compressmessages,reducingprocedures,improvemessagehandlingefficiency.Specifications,istostrictlyenforcethebanissuedbytheCommunistpartyauthoritiesindocumenthandlingregulationsashouldlaystr

54、essonhumane,personal,culturalandhuman.Receptionandworkdirectlywithpeople,receptionservicesdirectlyaffectingtheOfficeofpartyCommitteeTheimageoftheregion.Atthesametimestreenforcement,ensurethesafetyofthepartyandStatesecrets.ConfidentialworktomeetthedemandsofnewtechnologydevelopmentoOunt tchiteynegatic

55、vreeiated,a dared to use,i s toa nd care masse s life,focus work,in-dept h investigati on,more out bnformation a ndemerge ncyi nformation,ra pid e scalati on in stricta_L_,_ _ II _ L_ -_| -_|s to hold a numberof importantissues, boldsion,to resolvethesupervisi onover supervisi out boutique masterpie

56、ce,makeswe ofresearchrea ccorda nce withtheprocedures,firm, newspapevisi on,track i nspecti on, problemsarenotsolvove theesults moreto intole dofde cisir,ne wspapers,neverlate,failtoreed do notpass,theblamedoeson visinotholdon, m oretoin nationalsome haseffect of newspaperShang published,for a dvanc

57、e work,a nd publicitychangport,false claim and skimming. Investee 2.supervi sion and insist on,around and protectingt heirinterestdid notmiss, dissatisfactionofthemassesdidnotmiss,t herealrightofsupervision aut hority,with thede play due ofrole.Third,information submitted t o be pragmati c. Quicka n

58、d timel y.The ancients said:for the time system;statementback forthe tim ebei ng,nothing.Therefore,the submission of informationto do four,thatis,findtheprobl em faster,edit orialwriting ,sendand read faster approvalastotouchthetrut h,se kpracticalre sults.Adhere topeople -orie nted,t hemostimportan

59、t thing is to re alize,safeguarda nd develop the fundamentalinterest softhe overw helming majorityofthe people.Wecarryoutinspe ction,so m ustgo deep among t he masse s,go dee pintot herealities,always pay attebe nefits.Callwit h ca uti on,is supervisi ngde part mentsshould strengthe n the consci ous

60、ne ss ofaut horizedstri ctlyaccordi ng topr oce dure, preventi ngthesupe rvisionandexcessive toprevent adding burden tograss-roots.othi s end,the supervisi on De partment ofthe Party Committeeofsupervision mustbeunderndfee dba ck to implementquickly.To betr ueandntion t o the peoples liveli hood,t o