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基于格雷码的三维重构,exe程序,可以直接运行
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CCS3.3官方使用教程.pdf
【实例简介】主要是CCS3.3的入门操作,包括建立工程,运行程序,如何设置断点和观察窗,显示图形,如何创建自己的库工程以及剖析代码,分析函数等,来自于官网,绝大部分已经翻译
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语音处理_短时能量 _短时幅度_过零率matlab
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外汇EA源码,趋势,海龟,马丁,反马丁,变色龙等17个源码
源码2018ATR-Trailer趋势突破EA.mq42018framework.mq42018趋势闪交易.mq42009海龟交易系统 EA.mq42010_Turtle Channel 短线.mq4等共17个源码
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EKF,UKF,PF2 三种滤波算法的比较
完整的EKF,UKF,PF三种滤波算法的比较,包括状态估计,误差比较,和置信区间。
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H3C MIB【华三MIB库】
资源包含H3CMIB,包括交换机、WLAN、路由等MIB。
- 2020-12-11下载
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TDOA定位技术原理及算法
对TDOA定位技术的基本原理的描述,基于时间测量值的蜂窝无线定位算法第1期郭华:TDOA定位技术的基本原理和算法21值的不确定性度量。对于二维定位系统,、CEP定义为CEP≈(0.75s)ODOP(11)包含了一半以均值为中心的随机矢量实现的圆半G丑OP可作为从大量基站中选择所需定位基站的指径。如果定位估计器为元偏差的CEP即为MS相对标,选中的基站是使(nOP最小的基站,还可用于其真实位置的不确定性度量如图2所示。如果佔计建立新系统时作为选择基站位置的参考。器为有偏差的且以偏差B为界,则对于50%概率,MS的信计位置在距离B+CEP内,此时,CEP为一3基于COST259信道模型的算法仿复杂函数,通常用其近似表示,对于TDOA双曲线主位,CEP近似表示为CEP=0.75J2+02为了从分评估CHAN算法和 Taylor算法在不其中202分别为二维估计位置的方差同信道环境、不同测量条件下的定位性能,本文设定了多种仿真条件,考虑了实际应用中的可能出现的发射机位置情况,并且每次都在相同的条件下对MS做定位佔计。考核定位结果的均方根误差(RMSE)并以图表的形式直观的表示出米,结合理论分析,对这两和主CEP偏差矢量要的无线定位算法做评估。平均估计位置实际应用中,对尢线定位精度造成影响的因素有许多种。在本文中主要考虑以下因素:小区半径的大小、参与定位的基站数目、不同的信道参数、设图2圆误差概率CEP备的测量误差、定位基站的排列形状等。综合考虑2.3几何精度因子((丑OP)以上因素,仿真所需的主要条件如采用距离测量方法的定位系统准确率在很大程1)针对COS259模型中的A、B、C、D四种信度上取决于基站和待定位移动台MS之间的几何位道做仿真。不同的信道其参数T不同。在考察小置关系几何位置对定位准确率影响的度量即为几区半径和定位基站数目对定位性能的影响时主要考何精度因子(GDOP),定义为定位误差RMSE与测虑了A和B两种信道,考察基站的排列形状时主要距误差RMSE比率。GDOP表征了由于移动台与基考虑B和D两种信道。站几何位置关系对测距误差的放大程度。对于无偏(2)检测设备造成的测量误差:假设检测设备精差计器,GDOP为:度造成的TDOA误差服从均值为0,标准差为30mGDOP=Ntr[(AA(7)的高斯正态分布。在考察设备的测量误差对定位精度的影响时,标准差分别取:30m、60m、90m、120m、其中,tr()表示对结果矩阵求迹,即求矩阵主对角150m线兀素之和aA为根据某种特征测量值建立的线性3.1理想信道环境下测量设备误差对定位的影响方程组的系数矩阵,即仿真条件:小区半径R-2000m,参与定位的基Y=AX(8)站数目为3~7个,MS在1/12小区内均匀分布,假这里,基站位置Y是已知的M×1维向量,MS位置设信道为理想的LOS信道,由信道造成的NIOS误X是2×1维未知向量[xy],A是Mx矩阵,如果差为0。仅仅考由于检测设备的测量误差对算法AA是非奇异矩阵且M>2,则式(8)为方程数大于定位性能的影响。比较受限 Taylor算法与CHAN未知量数目的超定方程组,采用最小二乘LS)算算法的定位性能法获得MS估计位置定位结果如图3、图4和图5所示X=(AAAY(9)从图3到图5可以看出,当仅有理想高斯分布对于无偏差的估计器及二维双曲线定位系统的测量误差时,参与定位基站的数目已经不是很重GDOP可表小为要了,基站数目的变化不会影响两种算法的定位性GDOP=x +o v/ s(10)能。定位性能与测量误差直接相关(基本呈线性增这里s为测距误差标准差。GDOP与CEP有以长)。从3个图屮都可以发现CHAN算法的定位性下近似关系能要好与 Taylor算法。也就是说CHAN算法的抗C1994-2010chinaAcademicjOurnalElectronicPublishingHouseAllrightsreservedhttp://www.cnkinet22西安邮电学学报2007年1月高斯分冇;NLOS误差服从COST259模型。仿真结果如图6、图7和图8所示。图3基站数为3时理想高斯测量误差条件下, MTavlor算法与CHAN算法的定位性能比较图6基站数目为3时, TAylor算法和CHAN算法在BadUrban和 Urban环境下图4基站数为4时理想高斯测量误差条件下 MTavlor算法与CHAN算法的定位性能比较图7基站数目为4时, MAylor算法和CHAN算法在Barban和 Urban环境下的性能比画量柱准展图5基站数为7时理想高斯测量误差条件下 MAylor算法与CHAN算法的定位性能比较高斯噪声性能更好,较适用于LOS信道环境。图8基站数目为7时, TAylor算法和CHAN算法在3.2COsT259环境下小区大小定位基站数目及 BadUrban和Uban环境下的性能比排列对定位性能的影响标识说明: Badurban chan表小在 Badurban(T参与定位基站数目与小区大小对定位性能的=1)环境下CHAN算法的定位性能曲线; Urban-影响Chan表示在 Urban(T=0.4)环境下CHAN算法的仿真条件:参与定位的基站数目固定为(3~7),定位性能曲线; BadUrban Taylor表示在 Badurban小区半径大小由100400变化。MS在112(T=1)环境下 M Taylor算法的定位性能曲线;Ur小区内均匀分布,在 Badurban和Ubam环境下比 ban Taylor表示在 Urban(T=0.4)环境下 M Taylor较受限的 Taylor算法和CHN算法的定位性能。算法的定位性能曲线。Taylor算法的初始位置取MS的实际位置;设从图6到图8可以看出,在实际信道中,CHAN备的测量误差服从均值为0,标准差为30m的理想算法的定位性能要比 Taylor算法的性能差,这是o01994-2010ChinaaCademicjOurnalElectronicPublishingHouseAllrightsreservedhttp:/www.cnkinet第1期郭TDOA定位技术的基本原理和算法23由于CHAN算法本身就是针对運想高斯LoS环境想蜂窝状排列时 MAylor算法的定位性能曲线;提出米的,所以在实际信道中,由于NLOS误差的U Highway Chan表示在 Urban(T=0.4)环境下引入导致了CHAN算法性能的急剧下降。基站直线排列时CHAN算法的定位性能曲线我们也可以从图中发现,当NLOS误差分不相Highway Chan表示在 Rural(T=0.1)环境下同时,参与定位的基站数日的多少对算法的定位性基站直线排列时CHAN算法的定位性能曲线能没有多大的影响。但当小区半径大于3000m时,U Chan表示在 Urban(T=0.4)环境下基站理Taylor算法的性能呈直线下降,而且当小区半径增想蜂窝状排列时CHAN算法的定位性能曲线;大时, Maylor算法有可能出现不收敛情况。而CHan表示在Rurl(T-0.1)环境下基站理想CHAN算法性能变化较为平稳,且在任何情况下都蜂窝状排列时CHAN算法的定位性能由线能够给出定位结果。因此可以得出结论,在其它条件相同的条件下CHAN算法比 Taylor算法更适合与宏小区的无线非理想的基站分布对定位性能的影响仿真条件:小区半径从1000m~4000m,参与定位的基站数目为3。在类似高速公路的直线区域内基站一般呈直线分布。MS在1/12小区内均匀分布。比较受限 Taylor算法和CHAN算法在 Urban小区使加和Rura环境下的定位性能,以及基站直线分布与哩想蜂窝状分布下两种算法的定位性能。 Taylor图10基站直线排列与理想蜂窝状排列时在 Urban和算法中MS的初始位置取MS的实际位置。设备测Rurl环境下CHAN算法定位性能的比较量误差服从均值为0,标准差为30m的理想高斯分从图9和图10可以看出,基站的位置分布对两布。非视距误差NLOS满是COST259信道模型。种算法的定位性能影响都很人,其它条件不变时,当仿真结果如图9和图10所示基站呈直线分布时,定位性能都急剧下降。如果做樻向比较,在小、区半径较小时, Taylor算法有较好的定位性能。4小结通过以上的仿真与分析比较可以看出小区半径对CHAN算法的影响的程度比Taylor算法较小,在其它条件不变,只有小区半径增大的量准圣与时,CHAN算法的定位性能变化较为平稳。而Taylor算法的定位性能变化较为剧烈。说明在相同的图9基站直线排列与理想蜂窝状排列时,在 Urban和条件下,CHAN算法更适合与宏小区的定位。Rural环境下 TAylor算法定位性能的比较标识说明在LOS环境下,TDOA测量值的误差服从均U HighwayMTay表示在 Urban(T=0.4)环境值为0的埋想高斯分布CHAN算法的定位性能优于 Taylor算法的定位性能。所以CHAN算法更适下基站直线排列时 MAylor算法的定位性能曲线;合于LOS环境的定位。RHighwayM Tay表示在 Rural(T=0.1)环境下基站直线排列时 TAylor算法的定位性能曲线岀基站呈直线排列时,两种算法的定位性能与UMTay表示在 Urban(T=0.4)环境下基站理理想的蜂窝状分布时的定位性能相比急剧下降。在小区半径较小时, Taylor算法有较好的定位性能。想蜂窝状排列时 MAylor算法的定位性能曲线信道环境对定位性能有很大的影响,特别是对RMTav表示在 Rural(T=0.1)环境下基站理CIAN算法的影响更大一些。在郊区和远郊两种C1994-2010ChinaAcademicJournalElectronicPublishingHouseAllrightsreservedhttp://www.cnki.net4西安邮电学学报2007年1月算法都能取得较好的定位效果,基本能够满足FWrokshop j une 2001911的定位要求;但在城区的效果就明显下降,在闹21 J ames J. Caffery:Jr. and Gordon L. Stuber: Overvie市区几乎不能准确定位。因此,要在市区和闹市区of Radiolocation in CDMA Cellular Systems. TEEF获得较好的定位效果,就需要对定位算法进行改进,Communications Magazine April 1998 pp 38-45对如何取得更精确的TDOA测量值,更好的克服3]An Overview of Wireless Indoor geolocation Techniqueand Systems. Kaven Pahlavan. Xinrong Li. MikaNLOS误差进行深入旳研究。Ylianttila. Ranvir chana. And matti latva- aho. Mo-参考文献bile and wireless Communications Networks. IFIPTC6/ European commission NETWORKiNG 2000 Inter-[I Do menico Porcino. Philips Research Laboratories. Stannational Workshop. MWCN 2000. Paris France. Maydardisation of Location Technologies Mobile Location2000Principle and algorithm of doa location technologyGUO HuaDepartment of Electronic of Information Engineering Xi an University of Post and Telecommunications, Xi an 710121, China)Abstract: This thesis researches the wireless location algorithms based on time-related measurements in thWireless Cellular Network. By analyzing existing basic techniques and algorit hms in wireless location this thesisselects the TDOA algorithm for emp hases of research. First, we int roduce two typical al gorithms as Taylor algo-rithm and chan algorithm. Furthermore, we analyze and compare them by simulation under some commonmobile channel environment. In order to eval uate the performance of the two basic al gorithms in detail, the perfect channel and two typical mo bile communication channel model (CoST 259 and TiPl)are employed for future detailed simulation. In simulations, many relative parameters w hich may effect the performance of the loca-tion algorithms are examined, such as the cell size, the number of the base stations taking part in the locationservice, equip ment measurement errors, NLOS effect etcKey words: Time of Arrive (TOA); Difference Time of Arrive( TDOA); Angel of Arrive(AOA); NLOS error(上接第18页)Error code protection and scheme of Turbo code forwreless video frequency transmissionXU Hua, DONG Yirning, XIA YangCollege of Communication and Information EngineeringNanjing University of Posts and Telecommunications, Nanjing 210003, China)Abstract The characteristics of wireless channel such as time- variety and high BER requires not only strongerror correcting capability of channel coding method but also the ability to adjust bit rate according to the state ofwireless channel. The Rate Compatible Turbo code (RCP T)can fulfill such requirement, and protect video fre-quency stream with tr- s interleaver. The application of rCPt over the mo bile communication channel is intro-duced, and new schemes about adaptive coding system and unequal error protection are discussedKey words: Turbo codes; RCPT codes; puncture table, unequal error protectionC1994-2010ChinaAcademicJournalElectronicPublishingHouse.Allrightsreservedhttp://www.cnki.net
- 2020-11-28下载
- 积分:1
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中美智能驾驶白皮书
331页的研究报告,全方位展现中美智能驾驶的市场现状、关键技术环节发展情况以及落地情况,让读者深入了解无人驾驶产业中的基于与挑战。The Future of Autonomous Drivng in China and USa锋网新智驾出品发掘中美智能驾驶重要的创新者雷锋网智能驾驶白皮书人们往往以风囗来描述一个显著上升期中的行业,但只有很少人能真正察觉到在风口来临之前一批创新者的铺垫,毫无疑问,2017年所有人看到了在中国、美国、日本、德国等各地智能驾驶领域的繁荣,而各国的智能驾驶技术团队又以美国和中国最为集中,并且存在最广泛的应用市场。自2014年开始,雷锋网进入智能驾驶领域的报道。而在过去的10个月里,雷锋网团队在包括北京、上海、深圳、硅谷等各地,密集拜访了数百家智能驾驶技术团队,通过一手釆访、调研和亲身体验,之后又通过2个月时间梳理和筛选了近100家智能驾驶产业链中关键的技术公司,形成了这份《中美智能驾驶白皮书》。我们希望通过这近100家公司,向读者全方位展现中美智能驾驶的市场现状、关键技术环节发展情况以及落地情况,我们也希望读者能因此深入了解在这个庞大的产业中的机遇与挑战。以今天的关键技术发展水平为参照,我们希望你能通过这份白皮书提前看到未来3-5年在各个细分环节可能产生的机会和变化。本次在《中美智能驾驶白皮书》中,我们选取了13个关键细分领域的约100家公可进行深入解析,每个细分章节均包含f Av ng锋网新智驾出品●该领域的整体发展现状和存在问题●关键创新公司的技术水平、技术路线以及应用现状●中美两地技术和市场的差异比较。我们所选的这13个领域,涵盖了智能驾驶的集成方案、关键传感器技术、关键基础设施等,它们包括1.全栈自动驾驶2.自动驾驶卡车3.低速自动驾驶4.ADAS5.造车新势力6.激光雷达7.毫米波雷达8.自动驾驶芯片9.高精度地图10.模拟仿真系统1.高精度GNSs定位12.车辆改装13.V2X可以说,这13个领域就是在未来的汽车上实现智能驾驶的13个关键要素。这可能是目前市面上唯——份专注于智能驾驶领域一线技术公司创新现状的完整报告。这份报告的独特之处还在于●一线技术公司决策层的行业洞见,尤其是位于硅谷的自动驾驶技术公司。在The Future of Autonomous Drivng in China and USa锋网新智驾出品《中美智能驾驶白皮书》所分析的美国自动驾驶公司中,七成以上均是接受雷锋网直接采访,双方针对技术现状、技术路线、产品化策略进行详细讨论,有相当部分是雷锋网独家采集的内容。全面、结构化的细分领域解析。“知其然,更要知其所以然”。看到智能驾驶领域的繁荣,更要看到各个关键细分环节是否具有良好的发展,智能驾驶在落地应用之前需要构建一个完善的技术支撑体系。●全球化的视野,洞悉中美自动驾驶的差异。白皮书所分析的中、美公司分别各占约一半,各家也均是当地最具明星气质、最有潜力的公司。通过直观的阅读即可了解两地对自动驾驶看法的区别,以及各自的发展路径差异。另外,本白皮书的标题为“智能驾驶”,它可以泛指辅助驾驶、限定场景的自动驾驶,以及完全脱离人类驾驶员的无人驾驶等概念。由于本白皮书所涵盖的行业范围较为全面,故在标题中使用“智能驾驶”作为统称。另外,由于自动驾驶与无人驾驶这两个词在日常使用中更为广泛,所以在具体章节中,会更多地使用这两个词,特别是在涉及L4、L5级别的驾驶等级时。f Av ng锋网新智驾出品目录全栈自动驾驶7、国內全栈自动驾驶公司、国外全栈自动驾驶公司...20总结42自动驾驶卡车.43、国内自动驾驶卡车公司45国外自动驾驶卡车公司52三、总结59低速自动驾驶.·.·.·.·..............·.··..60、国內低速自动驾驶公司63、国外低谏自动驾驶公司8总结87ADAS89、国内ADAS公司95国外ADAS公司124134造车新势力136国内新造车公司139国外新造车公司162三、总结168激光雷达169国內激光雷达公司..172国外激光雷达公司182三、总结216亳米波雷达218、国内毫米波雷达公司,.222国外毫米波雷达公司.230总结240自动驾驶芯片e。要242涉足自动驾驶视觉芯片的公司245总结255高精度地图256、国内高精度地图公司259The Future of Autonomous Drivng in China and USa锋网新智驾出品、国外高精度地图公司264总结,,+279模拟仿真系统281自动驾驶模拟系统公司...285总结:嬴者通吃?294高精度GNSS定位295国內高精度GNSs定位公司297、国外高精度GNSS定位公司300三、总结304车辆改装305国内车辆改装公司.307国外车辆改装公司总结:一门会逐渐退出的业务?鲁,316VeXbbbb B....317、国內V2X公司,320国外∨2X公司324三、总结328The Future of Autonomous Drivng in China and USa锋网新智驾出品全栈自动驾驶▲0●本章所分析的可以说是离自动驾驶最近的公司。自动驾驶技术一般分为环境感知、决策规划和车輛控制三大部分,而所谓全栈自动驾驶公司,可以简单理解为提供除车辆硬件以外,包括这三类技术的鏗套自动驾驶软硬件解决方案的公司。虽然专注于自动驾驶卡车,以及特定场景自动驾驶(如景区、园区)技术的公司也是在开发全栈的自动驾驶技术,但本章所分析的公司则更加面向消费级市场,他们想改变亿万普通人未来出行的方式。在技术上,全栈自动驾驶公司无一例外,都选择了一步到位的L4-5级自动驾驶,而非渐进式的由辅助驾驶过渡到全自动驾驶在场景上,全栈自动驾驶公司面临的也会是最具挑战的城市道路驾驶环境,这也对他们的技术提出了更高的要求。正是因为上述这些原因,全栈自动驾驶公司的想像空间也更大。普华永道发布的《2017年数字化汽车报告》指出,出行市场将带来2.2万亿美元的产业规模,而截至2030年,消费者在出行上的花费将减少10%,且共享及自动驾驶汽车将占到37%的行驶里程。报告还指出,在自动驾驶的场景下,未来家庭在出行方面的开支将减少20%,而利润空间会急剧转向出行服务提供商,相比之下,传统汽车生产和销售的利润分成将从85%降至50%以下。在自动驾驶出行服务的场景下,汽车品牌之间的差异会减小,掌握主动权的是能够提供更优质出行服务的公司。而且车辆的生产会趋于标准化,仅有少数的车型就能满足市场上大部分的岀行需求,车辆的所有和销售模式也会发生变化。f Av ng锋网新智驾出品受智能化和共享化的影响,未来出行方式是车企、出行公司,还是新技术公司占主导,现在还没有明确的结论,但其中的关键一定与自动驾驶技术密不可分。汽车行业的利润分配将迎来大洗牌,这也是新技术公司看准的机会。本章接下来,雷锋网将根据对硅谷、北京、上海、深圳等地智能驾驶技术团队的密集拜访,分析以下几家公司。公司国别最新融资轮次投资机构核心业务驰中国Pe-A启明创投、英伟达、做出能实现城市共亨出行的自动驾技将门创投、华创资本术原型,开发大规模仿真云启资本、松禾资本Roadstar al中国天使轮采取家々感器融合软硬件结会的解决方MGem2(hm、案并与整车合作开发自动驾驶Pony, ai中国A红杉中国DG中国选择1高速自动驾驶,并与车厂合作开发的方式中国B+轮凯辉基金、CV纪源利用环境和驾驶行为数据提升自动驾驶Momenta资本、中法创新基金大脑美国C轮采用深学优先策略,定位在车队管Drive. alGrabVerizon ventures、Renovo aut美国未透露Samsung CalalysT、|聚焦远煋操控,打造一个跨越硬件和SCCa| Capital不辆的平Synapse partners美国C幹前身主做 Android第三方开源操作系统ConanPrcmjiInvcs的业务,后转做自动驾驶技术行业Auto x关国木透露上汽、 Gaintech为自动驾攻汽车提供软件(包括感知、Chola∨ enduresVoyage美国种子轮Initialized Capital相专注自动驾坡出杜车服务,从半封闭的Charles river社区场录转向自动驾驶服务Ventures.等美国未公布未公布特色在于将认知心埋学的研究应用在自动驾驶上BEssemer venture注于白动驾驶感知技术,根据与不同dccpscalc3i美国种子轮Pner、雅虎的创|>EM及供应应的合作方式,提供完整始人杨致远等的解决方案。Mayfield Fund和偏向深度学习,并涉及对机器人的研P|us∧美国未诱TEEC Angal Fund究.目标在干研发出级别的白动驾驶中国金沙江创投、光速中国系统大仝栈自动驾驶公司f Av ng锋网新智驾出品国内全栈自动驾驶公司景驰最地景驰科技是2017年4月成立的一家由人工智能驱动、以自动驾驶技术为核心的智能岀行公司,总部在美国硅谷。景驰的创始团队非常豪华,在成立的短时间内就获得了出众的成绩,也获得了投资者们的青睐,但在2017年底,它也陷入与百度商业秘密有关的纠纷之中。
- 2020-12-11下载
- 积分:1
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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
- 2020-12-08下载
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OFDMA System Analysis and Design
OFDMA系统分析与设计的国外经典教材Chapter 1 Introduction to OFDM and OFDMAChapter 2 Characterization of the Mobile Wireless ChannelChapter 3 Fundamentals of Digital Communications and NetworkingChapter 4 Fundamentals of OFDM and OFDMA: Transceiver StructureChapter 5 Physical Layer: Time and FrequencyChapter For a listing of recent titles in theArtech House Mobile Communications Library,turn to the back of this bookOFDMA System Analysis and DesignSamuel C. YangARTECHHOUSEBOSTON LONDONartechhouse. comLibrary of Congress Cataloging-in-Publication DataA catalog record for this book is available from the U.S. Library of CongressBritish Library cataloguing in Publication DataA catalogue record for this book is available from the british libraryISBN-13:978-1-60807-076-3Cover design by vicki KaneC 2010 Artech House685 Canton streetNorwood. MA 02062All rights reserved. Printed and bound in the United States of America. No partof this book may be reproduced or utilized in any form or by any means, elec-tronic or mechanical, including photocopying, recording, or by any informationstorage and retrieval system, without permission in writing from the publisherAll terms mentioned in this book that are known to be trademarks or servicemarks have been appropriately capitalized artech House cannot attest to theaccuracy of this information. Use of a term in this book should not be regardedas affecting the validity of any trademark or service mark10987654321To my beautiful wife JennyContentsPrefaceAcknowledgmentsXVCHAPTER TIntroduction to ofdm and ofdma1.1 Motivation1.2 Conventional FDm1.3 Advantages of FDm1.3.1 Intersymbol Interference(ISI)and Multipath Fading1.3.2 Modulation and Coding per Subcarrier1.3.3 Simple equalization1.4 Disadvantages of FDM1.5 Basics of ofdm1.6 Advantages of OFDM1.6.1 Low-Complexity modulation1.6.2 Spectral Efficiency1.7 Basics of ofdma1.8 Advantages of OFDMA121.9 Some Practical issues of ofdm and ofdma1.9.1 Time Domain: Interblock Interference131.9.2 Frequency Domain: Intercarrier Interference131.10 OFDM and Dsss141.11 Overview of the book14References15Selected BibliographyCHAPTER 2Characterization of the mobile wireless channel2.1 Introduction2.2 Link analysis2.3 Distance Dimension: Propagation Loss2.3.1 Path Loss2.3.2 Shadowing Loss24Contents2.3.3 Multipath Fading26Example 2.1282.3.4 Concluding Remarks292.4 Time Dimension: Multipath Delay Spread302.4.1 Delay Spread30Example 2.231Example 2.3312. 4.2 Coherence bandwidth322.4.3 Implications for OFDM352.5 Frequency Dimension: Doppler Spread362.5.1 Doppler Spread36Example 2. 4372.5.2 Coherence time2.5.3 Implications for OFDM402. 6 Conclusions41References43Selected Bibliography44ChAPTER 3Fundamentals of Digital Communications and Networking453.1 Introduction453.2 Basic Functions of a Transceiver453.3 Channel Coding473.3.1 Linear block codes473.3.2 Convolutional codes493.4 Symbol mapping and modulation3.5 Demodulation563. 5. 1 Matched Filter563.5.2 Symbol Error3.6 Adaptive Modulation and Coding603.7 Cyclic Redundancy Check(CRC)623.8 Automatic Repeat Request(arQ)643.8.1 Stop-and-Wait ARQ643.8.2 Sliding Window arQ653.9 Hybrid ARQ67References69Selected bibliographyCHAPTER 4Fundamentals of ofdm and ofdma: transceiver structure4.1 Basic Transmitter functions714.2 Time domain: guard time4.3 Frequency Domain: Synchronization744.4 Basic receiver functions754.5 Equalization764.6 OFDM Symbol79Contents4.7 OFDMA Transmitter844. 8 OFDMA Receiver4.9 OFDMA4.9.1 Frequency diversity4.9.2 Multiuser diversity914.9.3 Concluding Remarks4.10 Peak-to-Average Power ratio924.11 Conclusions93References94Selected Bibliography95CHAPTER 5Physical Layer: Time and Frequency975.1 Introduction5.2 Distributed Subcarrier Permutation: Forming Subchannels onDownlink5.2.1 Full Usage of Subchannels(FUSC1005.2.2 Partial Usage of Subchannels(PUSC)1015.2.3 Tile Usage of Subchannels 1(TUSC1)1025.2.4 Tile Usage of Subchannels 2(TUSC2)1025.3 Distributed Subcarrier Permutation: Forming Subchannels on Uplink 1025.3.1 Partial Usage of Subchannels(PUSC)1035.3.2 Optional Partial Usage of Subchannels(Optional PUSC)1035.4 Adjacent Subcarrier Permutation: Downlink and Uplink1045.5 Summary of Subcarrier Permutation Modes1045.6 Bursts and Permutation Zones1055.7 Subframes and frames1075.7.1 Preamble1105.7.2 Frame Control Header(FCH)1105.7.3 Downlink MAP (DL-MAP)and Uplink MAP(UL-MAP1115. 8 TDD and FDD5. 9 System Design Issues1125.9.1 Frequency Diversity and multiuser diversity1125.9.2 Segmentation1125. 10 Adaptive burst profiles1155.10.1 Burst Profiles1155.10.2 Channel Quality Feedback116References117ChAPTER 6Physical Layer: Spatial Techniques1196.1 Introduction6.2 Spatial Diversity: Receive Diversity1206.2.1 Receive Diversity: Antenna Selection1226.2.2 Receive Diversity: Maximal Ratio Combining6.3 Spatial Diversity: Transmit Diversity123Contents6.3. 1 Transmit Diversity: Open-Loop 2 X 11246.3.2 Transmit Diversity: Open-Loop 2X 21266.3.3 Transmit Diversity: Closed-Loop Antenna Selection128Example 6.11296.3.4 Transmit Diversity: Closed-Loop precoding1306.3.5 Remarks1326.4 Spatial Multiplexing1336.5 MIMO-OFDM1366.6 Beamforming1366.7 System Design Issues139References140Selected Bibliography141CHAPTER 7Medium Access control: architecture and data plane1437.1 MAC Architecture1437.2 Convergence Sublayer1457. 2.1 Address Mapping( Classification1467. 2.2 Header Suppression1467. 3 Common Part Sublayer1477.3.1ARQ1477. 3.2 MAC SDU and MAc pdu1487.3.3 Fragmentation/Packing1497.4 Security Sublayer152References152chaPTeR 8Medium Access Control Lower Control plane1538. 1 Introduction1538.2 Scheduler1538.3 Bandwidth Request1558.3.1 Request in Existing Uplink Allocation1568.3.2 Unicast Polling1568.3.3 Multicast and Broadcast Polling1578.3.4 Contention-Based Request for OFDMA1578.4 Control Signaling1588.5 Ranging1598.5.1 Initial Ranging1598.5.2 Periodic Ranging1608.5.3 Handover ranging1618.6 Power Control1618.6.1 Uplink Power Control: Closed-Loop1648.6.2 Uplink Power Control: Open-Loop1668.6.3 Assignment of Uplink Modulation and Coding8.6.4 Concluding Remarks168References169ContentsChaPTER 9Medium Access Control: Upper Control plane1719.1 Introduction1719.2 Network Entry1719.2. 1 Synchronization with Downlink of Base Station and acquisitionof parameters1739.2.2 Initial Ranging1739. 2.3 Negotiation of Mobile Capabilities1749.2.4 Security Procedures1749.2.5 Mobile registration1759.2.6 IP Connectivity1759.2.7 Connection Setup1769.3 Mobility Management: Link Handover1769.3.1 Cell Reselection1779.3.2 Hard Handover(HHO1799.3.3 Macro Diversity Handover(MDHO)1849.3.4 Fast Base Station Switching(FBSS1879.3.5 System Design Issue: H Add and h delete1899.3.6 Concluding Remarks1919.4 Mobility management: Network handover192References192CHAPTER 10Quality of Service(Qos)19510.1 Introduction19510.2 Definitions and Fundamental Concepts19510.2.1 Service Flows and Qos Parameters19510.2.2 Connections19610.3 Object Relationship Model19710.4 Service flow transactions19910.4.1 Creating a Service Flow19910.4.2 Changing a Service Flow20010.4.3 Deleting a Service Flow20310.5 QoS Parameters20410.6 Scheduling Services20610.6.1 Unsolicited Grant Service(UGS)20610.6.2 Real-Time Polling Service(rtPS20710.6.3 Extended Real-Time Polling Service(ertPS20710.6.4 Nonreal-Time Polling Service(nrtPS20810.6.5 Best Effort(BE)20810.6.6 Remarks209References210
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