线性预测及其Matlab实现，源码，程序
线性预测及其Matlab实现，源码，程序《现代电子技术》2009年第7期总第294期P测试·测量·自动化4骤(1)~(4)可对Ⅰ=1,2,…,P进行递推求解,其中:Ez=-aacorder,:)为最小均方预测误差;R为自相关系数;表示反射系数取值范围为[-1,1];a表示阶预测器的第j个系4结语数通过运算发现,其实在计算过程中,虽然目标是计算线性预测在语音处理方面的应用很广泛,而用一个p阶线性预测器的全部系数,但实际上在递推过程 Matlab来实现可以很直观地知道分析结果,为下一步中仅算出了所有除数低于p阶线性预测器的全部系数,将算法在DSP上的实现奠定基础。目前,语音处理最同时计算出了最小预测误差能量(递推式中反射系数的普遍的就是使用到网络上,而基于现代网络voIP使用取值范围是保证系统H(x)稳定性的充分必要条件,即到的语音编码中G.729正是其中一种。它的出现,使多项式A(z)的全部根都落在单位圆内用户能借助两台PC传输语音,也可以把PC上的语音从推导中得知,业(,)的物理意义可以理解为Sn转到手机上,交互式游戏爱好者们相互之间还可以借助的短时自相关函数因此,它反映了语音波形的实际情高科技控制器进行交流。况,即波形不同,值也不同然而a;的取值由更(j,i决定,并随亟(j,i的改变而改变,因此也可以说a;反映参考文獻了语音波形的实际情况3。[1]吴家安现代语音编码技术[M北京科学出版社,2008其 Matlab描述如下:[2]柏静,韦岗.一种基于线性预测与自相关函数法的语音基音function z=durbin(y, order)周期检测新算法[]电声技术,2005(8):43-46R=zeros(1, order+1)[3]王涌何剑春,刘盛新型的神经网络线性预测语音编码算aa=zeros(order, order)法[J].浙江工业大学学报,2007,35(2):65-68parcor=zeros (l,order),%autocorrelation[4]薛年喜. Matlab在数字信号处理中的应用[M].2版北京:N=size(y, 1);清华大学出版社,2008for h=l: order+1R(h)=0;[5]朱蓉,黄冰EVRC语音编码算法研究及仿真[].现代电子技术,2006,29(2):47-50R(h)=R(h)+y(f)*y(f-h+1)[6]范晶,和应民,王桂梅24Kb/s混合激励线性预测语音编end码的研究[].牡丹江师范学院学报,2007(4):13-14.parcor(1)=R(2)/R(1),[7]丛键,张知易.一种600b/s极低速率语音编码算法[].电aa(1,1)=parcor(1)E=(1- parcor(1)2)*R(1);子与信息学报,2007,29(2):429-433.for h=2: order[8]论:VoP语音技术与传统网络的融合发展LEB/OL]for f=1:h-1http://voip.microvoip.com/market/m1/200803/61433.ht-temp=temp+aa(h-1, f*R(h-f+1);ml,2008,endparcor(h)=(R(h+1)-temp)/%反射系数[9]语音技术在Internet上的新应用Leb/Ol].http://nc.mofaa(h, h)=parcor(h)com. gov. cn/news/1056746. html, 2006.for f=1:h-1aa(h, f)=aa(h-1, f)-parcor(h)* aa(h-l,h-f),[10] Rapidshare Advances in audio and Speech Signal ProcessingteChnologiesandApplications[db/ol].http://rapE=E*(l-parcor(h)2),idshare. com/files/31791068/IGI. rar. html, 2007end(上接第125页)Organic Optics and Optoelectronics[A]. IEEE/LEOS Sum参考文献s[C].1998[1]吴仲城多维力传感器设计及信号分析方法研究[D]北京:[4]熊幸果,陆德仁微力微位移的天平测试方法[J传感技术中国科学院等离子体物理研究所,2001学报,1997,10(2):47-52[2] Texas Instruments. MSC1210 Users Guide[z]. 2002.[5]洪跃,金士良新型微位移电容式传感器的研制[门.上海大[3]Sawada R, Higurashi E. Integrated Micro -displacement学学报,1995,1(6):652-657.Sensor that can be incorporated into Mini3- dimensional[6]胡永建,王晓梅基于MSC120的多路高精度温度采集系Actuator Stage. Broadband Optical Networks and Technolo-统模块[].电子技术应用,2003,29(7):36-38gies: An Emerging Reality/Optical MEMS/Smart Pixels/ [7J Texas Intruments MSC1210 Data SheetLzJ作者简介沈春山硕士研究生。主要研究方向为机器人传感器。135线性预测及其Mat1ab实现旧WANFANG DATA文献链接作者:曹华,李伟,谭艳梅, CAO Hua, LI Wei, tAN Yanmei作者单位:西机电职业技术学院,广西,南宁,530007刊名:现代电子技术sTe英文刊名:MODERN ELECTRONICS TECHNIQUE年,卷(期)2009,32(7)被引用次数1次参考文献(10条1.吴家安现代语音编码技术2002.柏静.韦岗一种基于线性预测与自相关函数法的语音基音周期检测新算法[期刊论文]电声技术2005(08)3.王涌何剑春.刘盛新型的神经网络线性预测语音编码算法[期刊论文]浙江工业大学学报2007(02)4.薛年喜 Matlab在数字信号处理中的应用20085.朱蓉.黄冰EVRC语音编码算法硏究及仿真[期刊论文]现代电子技术2006(02)6.范晶.和应民.王桂梅2.4Kb/s混合激励线性预测语音编码的研究2007(04)7.丛键.张知易一种600b/s极低速率语音编码算法[期刊论文]电子与信息学报2007(02)8.论:VoIP语音技术与传统网络的融合发展20089.语音技术在 Internet上的新应用200610. Rapidshare Advances in Audio and Speech Signal Processing: Technologies and Applications 2007相似文献(10条)1.学位论文鄂慧颖G.729语音编码算法的研究2007语音压缩编码技术是数字通信技术中非常重要的部分。随着通信、计算机网络等技术的飞速发展,语音压缩编码技术得到了快速发展和广泛应用CELP编码是上世纪八十年代发展起来的一种有效的语音压缩编码方案,现已广泛地应用于集群通信、多媒体通信以及IP电话通信中。G.729协议是CELP编码方案的一个特例,它是ITU-T推荐的语音压缩编码中最复杂的一种,它使用了当前语音压缩编码的各种先进技术,计算量较大,但是其编码合成语音质量较高,具有很高的研究价值。本文首先对G729协议的编解码方案及协议中应用的关键语音编码技术进行了剖析,在对G.729协议编码方案进行深入研究的基础上,对矢量量化算法进行了优化,减少了矢量码本搜索的复杂度,加快了矢量码本搜索速度;对固定码本搜索算法进行了改进,提出了一种自适应子矢量共轭结构代数码本激励算法,该算法保持了G.729共轭结构代数码本的优点,使编码传输速率从原来的&kbps降低倒η.2kbps,压缩了传输带宽,更重要的是,它的算法复杂度仅为原G.729固定码本搜索算法复杂度的1/2左右:最后,本文用 MATLAB搭建了编码器仿真平台,对改进算法进行了验证,仿真结果表明,改进后的编码器在降低算法复杂度和传输速率的前提下,译码合成语音质量仍然较髙,具有较好的可懂度、清晰度和自然度2.期刊论文汤婕多脉冲激励线性预测声码器的仿真实验分析一科技与生活2010,""(3本文主要介绍了用 MATLAB工具实现多脉冲激励线性预测( MPLPC)声码器.首先概述了多脉冲激励线性预测声器的编码方法,并用 MATLAB做了仿真实现先对语音信号进行线性预测分析,然后利用分析合成法对语音信号进行重构,并用到了量化编码.3.学位论文范晶混合激励线性预测语音编码的算法研究2008随着通信技术以及互联网语音实时传输技术的迅速发展,对语音的传输速率和存储容量都提岀了很高的要求,解决这些问题的主要途径之一就是语音编码。因此,语音编码的硏究,特别是低速率语音编码的研究,具有十分重要的实用意义在现有的语音编码硏究中,混合激励线性预测语音编码(ELP)是一种比较好的方法,它结合了二元激励、码激励和多带激励的优点,将短时语音段划分为若干子带,在每个子带中分别进行清浊音判别:在合成端,采用周期性脉冲序列和随机噪声的混合序列去激励语音合成滤波器,能在较低的码率下得到较好的再生语音。2.4kbps混合激励线性预测语音编码已经被确立为美国新的联邦语音编码标准本论文通过研究MELP的语音编解码算法的原理,对它的编解码过程做了比较深入的研究,我们发现在基音周期及线性预测系数量化这方面还可以进一定的改进。在标准MLP的算法中,对于那些包含有不规则周期的语音信号段,计算得到的互相关值较小,把它误认为是清音,因此会引入噪音。在这里采用了一种改变基音周期的算法,使基音周期的计算更加精确。此外,在对LSF进行量化的过程中,其码本的存储量与计算的复杂度都很大。针对于这一问题,我们提出了三级矢量量化的方法,从而可以把MLP的码率降到2.1kbps左右,仍有较好的合成语音质量本文最后在 MATLAB编程环境下对歴LP算法及其改进后的MELP算法进行了仿真,仿真结果表明经过解码后的语音信号及其改进后语音信号的输岀波形与原始语音信号的波形很相似,只是在能量较大的浊音段合成语音波形有相对较大的幅度以及有一定的时延,从而验证了该算法的可行性4.期刊论文修其丽. XIU Q1-1ⅰ多脉冲激励线性预测声码器设计与 Matlab仿真-烟台职业学院学报2006,12(3)由于在多脉冲激励线性预测声码器中要一次得到所有脉冲的位置和幅度是非常困难的,因此次优的序贯搜索方法被采用,即一次得到一个脉冲.用Matlab仿真观察合成语音效果是可以接受的5.学位论文杜志鑫基于MELP低速率语音编码2008作为低速率语音编码的一种重要算法,MELP( mixed excitation linear prediction)算法是其中一种非常优秀的编码方法,它在原有的LPC( linearprediction coder)编码的基础上,结合混合激励、多带激励、线性预测、矢量量化以及原型波形内插等编码方法的诸多优点,采用了一种新的更为符合人发音机制的语音生成模型来合成语音,并运用自适应频谱増强等技术,提髙合成语音与原始语音的匹配度,从而较好的实现了低码率的语音编码本论文通过研究MELP的语音编解码算法的原理,对它的编解码过程作了比较深入的研究,对其中的一些公式进行了理论推导,并作了仿真分析,最后研究了该算法的 MATLAB语言实现。在对混合激励(MELP)算法进行了深入研究后,在本文最后选取一种800bit/s的语音编码方案。6.期刊论文龙银东.刘宇红.敬岚.乔卫民. LONG YINDONG. LIU YUHONG. JING LAN. QIAO WEIMIN在 MATLAB环境下实现的语音识别-微计算机信息2007,23(34)介绍了一种基于 MATLAB的多个特定人连接词语音识别的方法,并提出了在进行端点检测时,引入平均的概念能进一步提高识别率.此设计是以LPC系数、DIw算法为核心的基于图形界面的设计.通过大量的实验测试,表明该方法基本达到屏蔽外界环境的影响,具有非常高的精度识别7.学位论文赖长庆混合激励线性预测声码器算法的研究2003该文以美国联邦标准2.4 kbps--MELP算法为基础,在 MATLAB上建立起了分析MELP算法的软件平台,对其性能进行了分析并提出了一些改进的建议;另外还针对MELP算法的特点对其软硬件实现进行了探讨.该文的第二章介绍了MELP声码器模型的原理,对其特征进行了详细的阐述,重点分析了各个特征的本质及其能够对提高合成语音质量起到的作用.第三章详细介绍了MELP声码器的基本算法,对其中采用的一些先进的技术手段如多级矢量量化(MSVQ)、高分辨率基音检测方法( SRPDA)等进行了重点的讲述.另外还对MLP声码器中使用的一些技术进行了实验分析,检验其效能.第四章利用在 MATLAB上搭建的分析平台上对语音信号进行了编解码的试验,分析了歴LP声码器的各种特征在语音编码中起到的作用.最后针对MLP声码器的特点,对其软硬件实现提岀了建议8.学位论文刘斌 HYBRID- MELP/CELP语音压缩编码算法的研究2005语音压缩编码技术是信号处理技术的一个重要的组成部分,它使用了信号处理领域大量从基础性到前沿性的思想、理论和实践方法.作为信号处理的主流学科之一,它的发展也一直是信号处理技术发展的重要促进力量.当今语音压缩编码算法主要分为侧重于对谱参数编码和侧重于对时间波形编码的两个大的算法类型.混合激励线性预测MEP编码算法和码激励线性预测CELP编码算法是这两大类算法的主要代表.MLP算法的主要特点是使用了多帶淸浊音判决,并且根据各频帶淸浊音的相对强度将清音成分和浊音成分按比例混合起来产生线性预测激励,其中的浊音激励成分采用傅立叶谱幅度的方法来表示CELP算法的主要特点是不区分语音信号的清浊音类型,而是统一使用基于AbS原理的时域波形匹配方法来产生线性预测激励,且该激励信号通过矢量码本来表示.本文讨论了MELP和CELP算法的原理和具体实现方法,并且基于 Matlab,主要是基于其 Simulink工具对两种算法进行了仿真实现针对MELP算法中基音提取相对繁琐的特点,本文提出了一种简化的MELP基音提取算法9.期刊论文纪友芳.刘桂斌. JI You-fang. LIU Gui-bin一种改进的线性预测语音编码技术及实现-计算机工程与应用2009,45(15)线性预测编码是实现语音编码的一项重要技术,介绍了线性预测编码技术的实现,提岀一种改进型的声激励线性预测语音编码方法.最后,将简单LPC语音编码与声激励LPC语音编码进行比较.实验结果表明,该方法能够很好地实现语音编码,声音效果也比简单LPC更理想.10.学位论文巫洪伟4kb/s代数码本激励线性预测语音编码的算法研究2007随着通信技术以及互联网语音实时传输技术的迅速发展,对语音的传输速率和存储容量都提岀了很高的要求,解决这些问题的主要途径之一就是语音编码码本激励线性预测(CELP)是国际公认的中速率下最成功语音编码算法,CELP算法能够提供中速率髙质量的合成语音,但是当编码速率降至4kb/s以下时语音质量明显下降。为了提高量化效率,必须増加激励矢量的长度,这时还用很少的符号脉冲来描述激励信号就会导致语音质量的急剧下降,这也就是传统的CELP算法在4kb/s编码速率以下质量难以提高的根本原因为此本文主要致力于研究在较少比特情况下优化代数码本激励,在G729算法的基础上,以20ms为一语音帧进行编解码,使传输速率降为G729语音编码算法的一半,从而提岀了一种具有较短延时和较低运算量的4kb/s脉冲散布代数码本激励线性预测算法。首先,根据G729算法的固定码本代数结构,设计了一种新的固定码书的代数结构,以降低算法的复杂度。然后,引进脉冲散布技术,对固定码本矢量进行散布处理,设计截止频率为3400Hz的有限冲击响应(FIR)低通滤波器实现脉冲散布技术本文最后在 MATLAB编程环境下仿真算法的性能,仿真结果表明经过解码后的语音信号输岀的波形与原始语音信号的输入波形很相似,只是在能量较小的清音段合成语音波形有相对较大的幅度以及有一定的时延,从而验证了算法的技术性能。文献(1条)1.雷翔霄.徐立娟智能软化击穿仪温控系统的设计与实现[期刊论文]现代电子技术2010(1本文链接http://d.g.wanfangdata.comcn/periodiCalxddzjs200907041.aspx授权使用:国防科技大学( gfk jdx),授权号:0e40ddb5-a6ff-4c0d-b44-9ec012765bf下载时间:2010年9月9日
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ISO16750-3-2012
ISO16750-3-2012Road vehicles — Environmentalconditions and testing for electricaland electronic equipment —Part 3:Mechanical loadsContents PageForeword.............................................................................................................................................Iso16750-3:2012[EContentsPageForewordScope12Normative references1Terms and definitions4Tests and requirements4.1ibration4.2 Mechanical shock274.3 Free fall…294.4 Surface strength/ scratch and abrasion resistance294.5 Gravel bombardmentCode letters for mechanical loads29Documentation…,…………111111130Annex A (informative) Guideline for the development of test profiles for vibration tests.32Annex B (informative) Recommended mechanical requirements for equipment depending on themounting location44Bibliography46C ISO 2012-All rights reservedIso16750-3:2012EForewordISo (the International Organization for Standardization) is a worldwide federation of national standardsbodies (Iso member bodies). The work of preparing International Standards is normally carried outthrough iso technical committees. Each member body interested in a subject for which a technicalcommittee has been established has the right to be represented on that committee. Internationaorganizations, governmental and non-governmental, in liaison with ISO, also take part in the workIso collaborates closely with the International Electrotechnical Commission (IEC) on all matters ofelectrotechnical standardizationInternational Standards are drafted in accordance with the rules given in the ISo/IEC Directives, Part 2The main task of technical committees is to prepare lnternational standards. draft InternationalStandards adopted by the technical committees are circulated to the member bodies for votingublication as an International Standard requires approval by at least 75 of the member bodiescasting a voteAttention is drawn to the possibility that some of the elements of this document may be the subject ofpatent rights. ISO shall not be held responsible for identifying any or all such patent rightsIso 16750-3 was prepared by Technical Committee ISO/TC 22, Road vehicle, Subcommittee SC 3,Electrical and electronical equipment.This third edition cancels and replaces the second edition (Iso 16750-3: 2007), which has beentechnically revisedISo 16750 consists of the following parts, under the general title road vehicles-Environmental conditionsand testing for electrical and electronic equipment:Part 1: GeneralPart 2: electrical loadsPart 3: Mechanical loadsPart 4: Climatic loadsPart 5: chemical loadso ISO 2012-All rights reservedINTERNATIONAL STANDARDIso16750-3:2012(E)Road vehicles- Environmental conditions and testing forelectrical and electronic equipmentPart 3Mechanical loads1 ScopeThis part of IS0 16750 applies to electric and electronic systems/components for road vehicles. Itdescribes the potential environmental stresses and specifies tests and requirements recommended forthe specific mounting location on/in the vehicleThis part of iso 16750 describes mechanical loads2 Normative referencesThe following referenced documents are indispensable for the application of this document. For datedreferences, only the edition cited applies For undated references, the latest edition of the referenceddocument (including any amendments applies.Iso16750-1, Road vehicles- Environmental conditions and testing forelectrical andelectronicequipment-Part 1: GeneralIEC 60068-2, 6, Environmental testing- Part 2-6: Testing, Test Fc: Vibration SinusoidalIEC60068-2, 14, Basicenvironmental testing procedures- Part 2-14: Tests-Test Nb: Change oftemperatureTEC 60068-2, 64, Environmental testing Part 2-64: Test methods -Test Fh -Vibration, broad-bandrandom(digital control)and guidanceIEC 60068-2, 80, Environmental testing- Part 2-80: Tests- Test Fi: Vibration - Mixed mode testingIEC 60068-2-31, Environmental testing procedures- Part 2: Tests; Test Ec: Free fall, Clause 5.23 Terms and definitionsFor the purposes of this document, the terms and definitions given in Iso 16750-1 app4 Tests and requirements4.1 Vibration41.1 GeneralThe vibration test metho ds specified consider various levels of vibration severities applicable to on-board electrical and electronic equipment. It is recommended that the vehicle manufacturer andsupplier choose the test method, the environmental temperature and vibration parameters dependingon the specific mounting locationFollowing the expressions in MIL-STD please noticeC ISO 2012-All rights reservedIso16750-3:2012EWhen applied properly, the environmental management and engineering processes described in this partof Iso 16750 can be of enormous value in generating confidence in the environmental worthiness andoverall durability. However, it is important to recognize that there are limitations inherent in laboratorytesting that make itimperative to use proper caution and engineering judgement when extrapolating theselaboratory results to results that may be obtained under actual service conditions. In many cases, realworld environmental stresses (singularly orin combination cannot be duplicated practically or reliably intestlaboratories. Therefore, users of this part of Iso 16750 should not assume that a system or componentthat passes laboratory tests of this part of Iso 16750 would also pass field/ fleet verification trialsThe specified values are the best estimation one can get up to the moment when results frommeasurements in the car are received - but they do not replace a car measurement!The specified values apply to direct mounting in defined mounting locations. Using a bracket formounting can resultin higher or lower loads. If the device under test ( DUT)is used in the vehicle with abracket then all vibration and mechanical shock test shall be done with this bracketCarry out the vibration with the dut suitably mounted on a vibration table. The mounting method (sused shall be noted in the test report. Carry out the frequency variation by logarithmic sweeping of 0,5octave/minute for sinusoidal tests and the sinusoidal part of sine on random tests. The scope of therecommended vibration tests is to avoid malfunctions and breakage mainly due to fatigue in the fieldTesting for wear has special requirements and is not covered in this part of ISo 16750Loads outside of the designated test frequency ranges are to be considered separatelNOTE Deviations from the load on the DUT can result, should vibration testing be carried out according tothis part of Iso 16750 on a heavy and bulky dut, as mounting rigidity and dynamic reaction on the vibrator tableexcitation are different compared to the situation in the vehicle. This deviation can be minimized by applying theaverage control method(see Annex A)Application of the weighted average control method according to IEC 60068-2, 64 is to be agreed uponSubject the dut during the vibration test to the temperature cycle according to iEC 60068-2, 14, withelectric operation according to diagram 1. Alternatively, a test at constant temperature may be agreed onOperate the dutelectrically as indicatedin Figure l at Tmin(Short functional testafterthe dUT completelyreached Tmin). This functional test shall be as short as possible- only long enough to check the properperformance of the dUt. This minimizes self-heating of the dUT. Additional electrical operation of theDUT between 210 min and 410 min of the cycle (see Figure 1)Additional drying of test chamber air is not permittedIn the vehicle, vibration stress can occur together with extremely low or high temperatures; for thisreason, this interaction between mechanical and temperature stress is simulated in the test, too. afailure mechanism is, for example, a plastic part of a system/component, which mellows due to the hightemperature and cannot withstand the acceleration under this condition2o ISO 2012-All rights reservedIso16750-3:2012[EYmax20aburditt0100200300400500600yY temperature[°C]x time [ minIa Operating mode 3.2 according to ISo 16750-1.b Operating mode 2. 1 according to ISo 16750-1One cycleFigure 1-Temperature profile for the vibration testTable 1- Temperature versus time for the vibration testTimeTemperaturemin°C0206040150-4021020300max41048020See Is016750-44.1.2 Tests4.1.2.1 Test I- Passenger car, engine4.1.2.1.1 PurposeThis test checks the dUt for malfunctions and breakage caused by vibrationThe vibrations of a piston engine can be split up into two kinds: Sinusoidal vibration which results from theunbalanced mass forces in the cylinders and random noise due to all other vibration-schemes of an engine,C ISO 2012-All rights reserved3Iso16750-3:2012Ee.g. closing of valves. In the lowest frequency range from 10 Hz to 100 Hz the influence of rough-roadconditions is taken into account. The main failure to be identified by this test is breakage due to fatigueNOTE 1 Road profile usually has negligible impact on engine-mounted components. Shock inputs are effectivelysolated by suspension, and engine-mounting systemsThe test profiles specified in the following clauses apply to loads generated by(four strokereciprocating enginesNotE 2 If the dut is to be tested for a specific resonance effect, then a resonance dwell test according to 8.3.2of IEC 60068-2, 6: 2007 can also be applied4.12.1.2Test4.1.2.1.2.1 GeneralIt is required to perform this test as a mixed mode vibration test according to IEC 60068-2, 80NOTE The test duration is based on A 4. The temperature in the chamher is above room temperature (rt)atthe end of the test (2 3/4 temperature cycles4.1.2.1.2.2 Sinusoidal vibrationPerform the test according to IEC 60068-2, 6, but using a sweep rate of s 0,5 octave/minute. Use a testduration of 22 h for each plane of the dUTUse curve l in Table 2/ Figure 2 for DUT intended for mounting on engines with 5 cylinders or fewerUse curve 2 in Table 2/Figure 2 for dUT test intended for mounting on engines with 6 cylinders or moreBoth curves may be combined to cover all engine types in one test2502001501005050100150200250300350400450500ⅩKeyamplitude of acceleration [m/s2IXfrequency [Hzcurve1(≤5 cylinders)curve 2(5 cylindersFigure 2- Vibration severity curves4o ISO 2012-All rights reservedIso16750-3:2012[ETable 2- values for max acceleration versus frequencyCurve 1(see Figure 2FrequencyAmplitude of accelerationHz100100200200240200270100440100Curve 2(see Figure 2)FrequencyAmplitude of accelerationHm/s2100100150150440150CombinationFrequencyAmplitude of accelerationH1001001501502002002402002551504401504,1.21.2.3 Random vibrationPerform the test according to IEC 60068-2, 64. Use a test duration of 22 h for each plane of the DUTThe r.m.s. acceleration value shall be 181 m/s2The psd versus frequency are referred to in Figure 3 and Table 3NoTE The Power Spectral Density(PSD)values (random vibration] are reduced in the frequency range of thesinusoidal vibration testC ISO 2012-All rights reserved5Iso16750-3:2012EY100100,110100100010000KeyY PSD [(m/s2)2/HzX frequency [Hz]Figure 3- PSD of acceleration versus frequencyTable 3- Values for frequency and PsDFrequencyPSDH:(m/s2)2/Hz1010100103000,5150020200024.1.2.1.3 RequirementBreakage shall not occur.Functional status a see iso 16750-1) is required during operating mode 3.2 as defined in ISo 16750-1and functional status C during periods with other operating modes4.1.2.2 Test II-Passenger car, gearbox4.1.2.2.1 PurposeThis test checks the dut for malfunctions and breakage caused by vibrationThe vibrations of a gearbox can be split up into two kinds which result partly from sinusoidal vibrationfrom unbalanced mass forces of the engine(e. g dominating orders) in the frequency range from 100 Hzto 440 Hz and vibration from the friction of the gear wheels and other schemes, which are tested in therandom part. In the lowest frequency range from 10 Hz to 100 Hz the influence of rough-road conditionsis taken into account The main failure to be identified by this test is breakage due to fatigueChanging the gears can create additional mechanical shock and shall be considered separatey brationsThe test profiles specified in the following subclauses apply to loads generated by gearbox vibo ISO 2012-All rights reserved
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