中英文翻译机器人

第一篇：中英文翻译机器人

中英文翻译机器人

机器人 工业机器人是在生产环境中用以提高生产效率的工具，它能做常规的装配线工作，或能做那些对于工人来说是危险的工作，例如，第一代工业机器人是用来在核电站中更换核燃料棒，如果人去做这项工作，将会遭受有害放射线的辐射。工业机器人亦能工作在装配线上将小元件装配到一起，如将电子元件安装在电路印刷板，这样，工人就能从这项乏味的常规工作中解放出来。机器人也能按程序要求用来拆除炸弹，辅助残疾人，在社会的很多应用场合履行职能。机器人可以认为是将手臂末端的工具、传感器和（或）手爪移到程序指定位置的一种机器。当机器人到达位置后，他将执行某种任务。这些任务可以是焊接、密封、机器装料、拆卸以及装配工作。除了编程以及系统的开停之外，这些工作可以在无人干预下完成。如下叙述的是机器人系统基本术语： 机器人是一个可编程、多功能的机器手，通过给要完成的不同任务编制各种动作，它可以移动零件、材料、工具以及特殊装置。这个基本定义引导出后续段落的其他定义，从而描绘出一个完整的机器人系统。预编程位置点是机器人为完成工作而必须跟踪的轨迹。在某些位置点上机器人将停下来做某写操作，如装配零件、喷涂油漆或焊接。这些预编程点贮存在机器人的贮存器中，并为后续的连续操作所调用，而且这些预编程点像其他程序数据一样，可在日后随工作需要而变化。因而，正是这种可编程的特征，一个工业机器人很像一台计算机，数据可在这里储存、后续调用与编辑。机械手上机器人的手臂，它使机器人能弯曲、延伸、和旋转，提供这些运动的是机器手的轴，亦是所谓的机器人的自由度。一个机器人能有 3—16 轴，自由度一词总是与机器人轴数相关。工具和手爪不是机器人自身组成部分，但它们安装在机器人手臂末端的附件。这些连在机器人手臂末端的附件可使机器人抬起工件、点焊、刷漆、电弧焊、钻孔、打毛刺以及根据机器人的要求去做各种各样的工作。机器人系统还可以控制机器人的工作单元，工作单元是机器人执行任务所处的整体环境，包括控制器、机械手、工作平台、安全保护装置或者传输装置。所有这些为保证机器人完成自己任务而必需的装置都包括在这一工作单元中。另外，来自外设的信号与机器人通讯，通知机器人何时装配工件、取工件或放工件到传输装置上。机器人系统有三个基本部件：机械手、控制器和动力源。A.机械手 机械手做机器人系统中粗重工作，它包括两个部分：机构和附件，机械手也有联接附件基座，图 1 表示了一机器人基座与附件之间的联接情况。图 1 机械手基座通常在工作区域的地基上，有时基座也可以移动，在这种情况下基座安装在导轨或轨道上，允许机械手从一个位置移动到另外一个位置。正如前面所提到的那样，附件从机器人基座上延伸出来，附件就是机器人的手臂，它可以是直接型，也可以是轴节型手臂，轴节型手臂也是大家所知的关节型手臂。机械臂使机械手产生各轴的运动。这些轴连在一个安装基座上，然后再连到托架上，托架确保机械手停留在某一位置。在手臂的末端上，连接着手腕（图 1），手腕由辅助轴和手腕凸缘组成，手腕是让机器人用户在手腕凸缘上安装不同工具来做不同种工作。机械手的轴使机械手在某一区域内执行任务，我们将这个区域为机器人的工作单元，该区域的大小与机器手的尺寸相对应，（图 2）列举了一个典型装配机器人的工作单元。随着机器人机械结构尺寸的增加。工作单元的范围也必须相应增加。图 2 机械手的运动由执行元件或驱动系统来控制。执行元件或驱动系统允许个轴在工作单元内运动。驱动系统可用电气、液压和气压动力，驱动系统所产生的动力经机构转变为机械能，驱动系统与机械传动链相匹配。有链、齿轮和滚珠丝杠组成的机械传动链驱动着机器人的各轴。B.控制器 机器人控制器是工作单元的核心。控制器储存着预编程序供调用、控制外设，及与厂内计算进行通讯以满足产品经常更新的需要。控制器用于控制机器手运动和在工作单元内控制机器人外设。用户可通过手持的示教盒将机械手运动的程序编入控制器。这些信息储存在控制器的存储器中以备后续调用，控制器储存了机器人系统的所有编程数据，它能储存几个不同的程序，并且所有这些程序均能编辑。控制器要求能够在工作单元内外设进行通信。例如控制器有一个输入端，它能标识某个机加工操作何时完成。当该加工循环完成后，输入端接通，告诉控制器定位机械手以便能抓取已加工工件，随后，机械手抓取一未加工件，将其放置在机床上。接着，控制器给机床发出开始加工的信号。控制器可以由根据事件顺序而步进的机械式轮鼓组成，这种类型的控制器可用在非常简单的机械系统中。用于大多数人系统中的控制器代表现代电子学的水平，是更复杂的装置，即它们是由微处理器操纵的。这些微处理器可以是 8 位，16 位或 32 位处理器。它们可以使得控制器在操纵工程中显非常柔性。控制器能通过通信线发送信号，使它能与机械手各轴交流信息，在机器人的机械手和控制器之间的双向交流信息可以保持操作和位置经常更新，控制器亦能控制安装在机器人手腕上的任何工具。控制器也有与厂内各计算机进行通信的任务，这种通信联系使机器人成为计算机辅助制造（CAM）系统的一个组成部分。存储器。基于微处理器的系统运行时要与固态的存储装置相连，这些存储装置可以是磁泡，随机存储器、软盘、磁带等。每种记忆存储装置均能贮存、编辑信息以备后续调用和编辑。C.动力源 动力源是给机器人和机器手提供动力的单元。传给机器人系统的动力源有两种，一种是用于控制器的交流电，另一种是用于驱动机械手各轴的动力源，例如，如果机器人的机械手是有液压和气动驱动的，控制信号便传送到这些装置中，驱动机器人运动。对于每一个机器人系统，动力是用来操纵机械手的。这些动力可来源与液压动力源、气压动力源或电源，这些能源是机器人工作单元整体的一部分。

robot The industr ial robot is a tool t hat is used in t he manufact ur ing environment to increase product ivit y.It can be used to do rout ine and tedious assembly line jobs, or it can per form jobs t hat might be hazardous to t he human worker.For example ,one of t he first indust r ial robot was used to replace t he nuclear fuel rods in nuclear power plant s.A human doing t his job might be exposed to har mful amount s of radiat ion.The indust r ial robot can also operat e on t he assembly line, putt ing toget her small component s, such as placing electronic component s on a pr int ed circuit board.Thus, t he human worker can be relieved of t he rout ine operat ion of t his t edious t ask.Robot s can also be programmed to defuse bombs, to serve t he handicapped, and to per for m funct ions in numerous applicat ions in our societ y.The robot can be t hought of as a machine t hat will move an endoperat ed.t hese microprocessors are eit her 8-bit , 16-bit ,or 32-bit processors.t his power allows t he controller to be ver y flexible in it s operat ion.The cont roller can send elect ric signals over communicat ion lines t hat allow it to t alk wit h t he var ious axes of t he manipulator.This t wo-way communicat ion bet ween t he robot manipulator and t he cont roller maint ains a const ant updat e of t he end t he operat ion of t he syst em.The cont roller also controls any tooling placed on t he end of t he robot ’s wr ist.The cont roller also has t he job of communicat ing wit h t he different plant comput ers.The communicat ion link est ablishes t he robot as part a comput er-assist ed manufact ur ing(CAM)syst em.As t he basic definit ion st at ed, t he robot is a reprogrammable, mult ifunct ional manipulator.Therefore, t he controller must contain some of memor y stot age.The microprocessor-based syst ems operates in conjunct ion wit h solid-st at e divices.These memor y devices may be magnet ic bubbles, random-access memony, floppy disks,or magnet ic tape.Each memor y storage device stores program infor mat ion fir or for edit ing.C.power suppy The power supply is t he unit t hat supplies power to t he controller and t he manipulator.The t ype of power are delivered to t he robot ic syst em.One t ype of power is t he AC power for operat ion of t he cont roller.The ot her t ype of power is used for dr iving t he var ious axes of t he manipulator.For example, if t he robot manipulator is cont rolled by hydraulic or pneumat ic drives, cont rol singals are sent to t hese devices causing mot ion of t he robot.For each robot ic syst em, power is required to operat e t he manipulator.This power can be developed from eit her a hydraulic power source, a pneumat ic power source,or an elect ric power source.There power sources are part of t he total component s of t he robot ic work cell.

第二篇：中英文翻译--工业机器人-精品

Industrial robots There are variety of definitions of the term robot.Depending on the definition used, the number of robot installations worldwide varies widely.Numerous single-purpose machines are used in manufacturing plants that might appear to be robots.These machines are hardwried to perform a single function and cannot be reprogrammed to preform a different function.Such single-purpose machines do not fit the definition for industrial robots that is becoming widely accepted.this definition was developed by the Robot Institute of America.A robot is a reprogrammable multifunctional mainipulator designed to move material, parts, tools, or specialized devices through variable programmed motions for the performance of a variety of tasks.Note that this definition contains the words reprogrammable and multifunctional.It is these two characteristics that separate the ture industrial robot from the various single-purpose machines used in modern manufacturing firms.The term “reprogrammable” implies two things: The robot operates according to a written program, and this program can be rewritten to accommodate a variety of manufactureing tasks.The term “multifunctional” means that the robot can, through reprogramming and the use of different end-effectors, perform a number of different manufacturing tasks.Definitions written around these two critical characteristics are becoming the accpted definitions among manufacturing professionals.The first articulated arm came about in 1951 and was used by the U.S.Atomic Energy Commission.In 1954, the first programmable robot was designed by George Devol.It was based on two important technologies:(1)Numerical control(NC)technology.(2)Romote manipulator technology.Numerical contorl technology provided a form of machine control ideally suited to robots.It allowed for the control of motion by stored programs.These programs contain date points to which the sequentially moves, timing signals initiate action and to stop movement, and logic staements to allow for decision making.Remote manipulator technology allowed a machine to be more than just another NC machine.It allowed such machines to become robots that can perform a variety of manufacturing tasks in both inaccessible and unsafe environments.By merging these two technologies, Devol developed the first industrial robot, an unsophisticated programmable materials handling machine.The first commerically produced robot was developed in 1959.In 1962, General Motors Corporation.This robot was produced by Unimation.A major step forword in robot control occurred in 1973 with the development of the T-3 industrial robot by Cincinnati Milacron.The T-3 robot was the first commercially produced industrial robot controlled by a minicomputer.Numerical control and remote manipulator technology prompted the wide-scale development and use of industrial robots.But major technological developments do not take place simply because of such new capabilities.Something must provide the impetus for taking advantage of these capabilities.In the case of industrial robots, the impetus was economics.The rapid inflation of wages experienced in the 1970s tremendously increased the personnel costs of manufacturing firms.At the same time, foreign competition became a serious problem for U.S.manufacturers.Foreign manufacturers who had undertaken automation on a wide-scale basis, such as those in Japan, began to gain an increasingly large share of the U.S.and world market for manufactured goods, particularly automobiles.Through a variety of automation techniques including robots, Japanese manufacturers, beginning in the 1970s, were able to produce better automobiles more cheaply than nonautomated U.S.manufacturers.Consequently, in order to survive, U.S.manufacturers were forced to consider any technological developments that could help improve productivity.It became imperative to produce better products at lower costs in order to be competitive with foreign manufacturers.Other factors such as the need to find better ways of performing dangerous manufacturing tasks contributed to the development of industial robots.However, the principal rationale has always been, and is still, improved productivity.One of the principal advantages of robots is that they can be used in settings that are dangerous to humans.Welding and parting are examples of applications where robots can be used more safely than humans.Even though robots are closely associated with safety in the workplace, they can, in themselves, be dangerous.Robots and robot cells must be carefully designed and configured so that they do not endanger human workers and other machines.Robot work envelops should be accurately calculated and a danger zone surrounding the envelope clearly marked off.Red flooring strips and barries can be used to keep human workers out of a robot’s work envelope.Even with such precautions it is a good idea to have an automatic shutdown system in situations where robots are used.Such a system should have the capacity to sense the need for an automatic shutdown of operations.Fault-tolerant computers and redundant systems can be installed to ensure proper shutdown of robotics systems to ensure a safe enviroment.About componets of a robot system, the componets of a robot system could be discussed either from a systems point of view.Physically, we could divide the system, and controller(computer).Likewise, the robot itself could be partitioned anthropomorphically into base, shoulder, elbow, wrist, gripper, and tool.Most of these terms require little explanation.Consequently, we will describe the components of a robot system from the point of view of information transfer.That is, what information or signal enters the component;what logical or arithmetic operation does the component perform;and what information or signal does the component produce? It is important to note that the same physical component may performs many different information processing operations(e.g., a central computer performs many different calculations on different data).Likewise, two physically separate components many perform identical informations(e.g., the shoulder and elbow actuators both convert signals to motion in very similar ways).中文：

工业机器人

有许多关于机器人这个术语的定义。采用不同的定义，全世界各地机器人的数量就会发生很大的改变。在制造工厂中使用的许多但用途机器可能会看起来像机器人。这些机器是硬连线的，用来完成单一的工作，不能通过重新编程的方法去完成不同的工作。这种单用途的机器不能满足被人们日益广泛接受的关于工业机器人的定义。这个定义是由美国机器人协会提出的: 机器人是一个可以改编程序的多功能操作器，被设计用来按预先编制的，能够完成多种作业的运动程序运送材料，零件，工具或者专用设备。

注意在这个定义中包含有“可以改编程序”和“多功能”这两个词。正是这两个词将真正的机器人与现代制造工厂中使用的单一用途的机器区分开来。“可以改编程序”这个术语意味着两件事：机器人根据编写的程序工作，以及可以通过重新编程来适应不同种类的制造工作的需要。

“多功能”这个词意味着机器人能通过编程和使用不同的末端执行机构，来完成不同的制造工作。围绕着两个关键特征所撰写的定义正在变成为制造业的专业人员接受的定义。

第一个带有活动关节的手臂于1951年被研制出来，由美国原子能委员会使用。在1954年，第一个可以编程的机器人由乔治·狄弗设计出来。他基于下面来两项重要技术：

（1）数字控制（NC）技术。（2）远程操作器技术。

数字控制技术提供了一种非常适合机器人的机器控制技术。它可以通过存储的程序对运动进行控制。这些程序包含机器人进行顺序运动的数据，开始运动和停止运动的时间控制信号，以及作出决定所需要的逻辑语句。

远程操作器技术使得一台机器的性能超出一台数控机器。它可以使这种机器能够在不容易进入和不安全的环境中完成各种制造任务。通过融合了上述两种技术，狄弗研制出第一个机器人，它是一个不复杂的，可以编程的物料运送机器人。

第一台商业化生产的机器人在1959年研制成功。通用汽车公司在1962年安装了第一台用于生产线上的工业机器人，它是尤尼梅森公司生产的。在1973年，辛辛提那·米兰克朗公司研制出T-3工业机器人，在机器人的控制方面取得了较大的进展。T-3机器人是第一台商业化生产的采用计算机控制的机器人。

数字控制技术和远程操作器技术推动了大范围的机器人研制和应用。但是主要的技术进步并不仅仅是由于这些新的应用能力而产生的，而是必须有利用这些能力所得到的效益来提供动力。就工业机器人而言，这个动力是经济性。

在20世纪70年代中，工资的快速增长大大增加了制造业的企业中的人工费用。与此同时，来自国外的竞争成为美国制造业所面临的严重考验。诸如日本等外国的制造厂家在广泛的应用了自动化技术之后，其工业产品，特别是汽车，在美国和世界市场中占据了日益增大的份额。

通过采用包括机器人在内的各种自动化技术，从70年代开始，日本的制造厂家能够比没有采用自动化技术的美国制造厂家生产更多的和更便宜的汽车。随后，为了生存，美国制造厂家进行竞争，必须以比较低的成本，生产出更好的产品。其他的因素，注入寻找能够更好的完成带有危险性的制造工作的方式也促进了工业机器人的发展。但是，主要的理由一直是，而且现在仍然是提高生产率。

机器人的一个优点是它们可以在相对于人类来说是危险的环境中工作。采用机器人进行焊接和切断工作室比由人工来完成这些工作更安全的例子。尽管机器人与工作地点的安全密切相关，它们本身也可能是危险的。

应该仔细的设计和配置机器人和机器人单元，使它们不会伤害人类和其他机器。应该精确的计算出机器人的工作范围，并且在这个范围的四周清晰地标出危险区域。可以采用在地上划出红颜色的线和设置障碍物以阻止工人进入机器人的工作范围。

即使有了这些预防措施，在使用机器人的场地中设置一个自动停止工作的系统仍然不失为一个好主意。机器人这个系统应该具有能够检测出是否有需要自动停止工作的要求的能力。为了保证能有一个安全的环境，应当安装容错计算机和冗余系统来保证在适当的时候停止机器人的工作。

关于机器人系统的组成部分，可以从物质的观点也可以从系统的观点来讨论机器人系统的组成部分。从物质上看，我们可以将机器人分为机器人，电源系统和控制器（计算机）。机器人本身可以像人一样被分为基座，肩，肘，腕，抓持器和工具。这些术语中的大部分不需要做任何解释。

因此，我们将根据信息传递的观点来描述机器人系统的组成部分。也就是，什么信息或者信号进入计算机的组成部分，这个组成部分进行何种逻辑或者算术运算，这个组成部分产生什么信息或者信号？应该认识到，同一个组成部分可以完成许多不同的信息处理工作（例如，中心计算机可以根据不同的数据进行许多不同种类的计算），这一点是很重要的。与之相似，在结构上分开的两个组成部分可以进行相同的信息操作（例如，肩部和肘部的执行机构用非常相似的方式将信息转换为运动）。

注：出自《机械工程专业英语》

第三篇：机器人外文翻译(文献翻译_中英文翻译)

外文翻译

外文资料：

Robots First, I explain the background robots, robot technology development.It should be said it is a common scientific and technological development of a comprehensive results, for the socio-economic development of a significant impact on a science and technology.It attributed the development of all countries in the Second World War to strengthen the economic input on strengthening the country's economic development.But they also demand the development of the productive forces the inevitable result of human development itself is the inevitable result then with the development of humanity, people constantly discuss the natural process, in understanding and reconstructing the natural process, people need to be able to liberate a slave.So this is the slave people to be able to replace the complex and engaged in heavy manual labor, People do not realize right up to the world's understanding and transformation of this technology as well as people in the development process of an objective need.Robots are three stages of development, in other words, we are accustomed to regarding robots are divided into three categories.is a first-generation robots, also known as teach-type robot, it is through a computer, to control over one of a mechanical degrees of freedom Through teaching and information stored procedures, working hours to read out information, and then issued a directive so the robot can repeat according to the people at that time said the results show this kind of movement again, For example, the car spot welding robots, only to put this spot welding process, after teaching, and it is always a repeat of a work It has the external environment is no perception that the force manipulation of the size of the work piece there does not exist, welding 0S It does not know, then this fact from the first generation robot, it will exist this shortcoming, it in the 20th century, the late 1970s, people started to study the second-generation robot, called Robot with the feeling that This feeling with the robot is similar in function of a certain feeling, for instance, force and touch, slipping, visual, hearing and who is analogous to that with all kinds of feelings, say in a robot grasping objects, In fact, it can be the size of feeling out, it can through visual, to be able to feel and identify its shape, size, color Grasping an egg, it adopted a acumen, aware of its power and the size of the slide.Third-generation robots, we were a robotics ideal pursued by the most advanced stage, called intelligent robots, So long as tell it what to do, not how to tell it to do, it will be able to complete the campaign, thinking and perception of this man-machine communication function and function Well, this current development or relative is in a smart part of the concept and meaning But the real significance of the integrity of this intelligent robot did not actually exist, but as we continued the development of science and technology, the concept of intelligent increasingly rich, it grows ever wider connotations.Now, I would like to briefly outline some of the industrial robot situation.So far, the industrial robot is the most mature and widely used category of a robot, now the world's total sales of 1.1 million Taiwan, which is the 1999 statistics, however, 1.1 million in Taiwan have been using the equipment is 75 million, this volume is not small.Overall, the Japanese industrial robots in this one, is the first of the robots to become the Kingdom, the United States have developed rapidly.Newly installed in several areas of Taiwan, which already exceeds Japan, China has only just begun to enter the stage of industrialization, has developed a variety of industrial robot prototype and small batch has been used in production.Spot welding robot is the auto production line, improve production efficiency and raise the quality of welding car, reduce the labor intensity of a robot.It is characterized by two pairs of robots for spot welding of steel plate, bearing a great need for the welding tongs, general in dozens of kilograms or more, then its speed in meters per second a 5-2 meter of such high-speed movement.So it is generally five to six degrees of freedom, load 30 to 120 kilograms, the great space, probably expected that the work of a spherical space, a high velocity, the concept of freedom, that is to say, Movement is relatively independent of the number of components, the equivalent of our body, waist is a rotary degree of freedom We have to be able to hold his arm, Arm can be bent, then this three degrees of freedom, Meanwhile there is a wrist posture adjustment to the use of the three autonomy, the general robot has six degrees of freedom.We will be able to space the three locations, three postures, the robot fully achieved, and of course we have less than six degrees of freedom.Have more than six degrees of freedom robot, in different occasions the need to configure.The second category of service robots, with the development of industrialization, especially in the past decade, Robot development in the areas of application are continuously expanding, and now a very important characteristic, as we all know, Robot has gradually shifted from manufacturing to non-manufacturing and service industries, we are talking about the car manufacturer belonging to the manufacturing industry, However, the services sector including cleaning, refueling, rescue, rescue, relief, etc.These belong to the non-manufacturing industries and service industries, so here is compared with the industrial robot, it is a very important difference.It is primarily a mobile platform, it can move to sports, there are some arms operate, also installed some as a force sensor and visual sensors, ultrasonic ranging sensors, etc.It’s surrounding environment for the conduct of identification, to determine its campaign to complete some work, this is service robot’s one of the basic characteristics.For example, domestic robot is mainly embodied in the example of some of the carpets and flooring it to the regular cleaning and vacuuming.The robot it is very meaningful, it has sensors, it can furniture and people can identify, It automatically according to a law put to the ground under the road all cleaned up.This is also the home of some robot performance.The medical robots, nearly five years of relatively rapid development of new application areas.If people in the course of an operation, doctors surgery, is a fatigue, and the other manually operated accuracy is limited.Some universities in Germany, which, facing the spine, lumbar disc disease, the identification, can automatically use the robot-aided positioning, operation and surgery Like the United States have been more than 1,000 cases of human eyeball robot surgery, the robot, also including remote-controlled approach, the right of such gastrointestinal surgery, we see on the television inside.a manipulator, about the thickness fingers such a manipulator, inserted through the abdominal viscera, people on the screen operating the machines hand, it also used the method of laser lesion laser treatment, this is the case, people would not have a very big damage to the human body.In reality, this right as a human liberation is a very good robots, medical robots it is very complex, while it is fully automated to complete all the work, there are difficulties, and generally are people to participate.This is America, the development of such a surgery Lin Bai an example, through the screen, through a remote control operator to control another manipulator, through the realization of the right abdominal surgery A few years ago our country the exhibition, the United States has been successful in achieving the right to the heart valve surgery and bypass surgery.This robot has in the area, caused a great sensation, but also, AESOP's surgical robot, In fact, it through some equipment to some of the lesions inspections, through a manipulator can be achieved on some parts of the operation Also including remotely operated manipulator, and many doctors are able to participate in the robot under surgery Robot doctor to include doctors with pliers, tweezers or a knife to replace the nurses, while lighting automatically to the doctor's movements linked, the doctor hands off, lighting went off, This is very good, a doctor's assistant.Robot is mankind's right-hand man;friendly coexistence can be a reliable friend.In future, we will see and there will be a robot space inside, as a mutual aide and friend.Robots will create the jobs issue.We believe that there would not be a “robot appointment of workers being laid off” situation, because people with the development of society, In fact the people from the heavy physical and dangerous environment liberated, so that people have a better position to work, to create a better spiritual wealth and cultural wealth.译文资料：

机器人

首先我介绍一下机器人产生的背景，机器人技术的发展，它应该说是一个科学技术发展共同的一个综合性的结果，同时，为社会经济发展产生了一个重大影响的一门科学技术，它的发展归功于在第二次世界大战中各国加强了经济的投入，就加强了本国的经济的发展。另一方面它也是生产力发展的需求的必然结果，也是人类自身发展的必然结果，那么随着人类的发展，人们在不断探讨自然过程中，在认识和改造自然过程中，需要能够解放人的一种奴隶。那么这种奴隶就是代替人们去能够从事复杂和繁重的体力劳动，实现人们对不可达世界的认识和改造，这也是人们在科技发展过程中的一个客观需要。

机器人有三个发展阶段，那么也就是说，我们习惯于把机器人分成三类，一种是第一代机器人，那么也叫示教再现型机器人，它是通过一个计算机，来控制一个多自由度的一个机械，通过示教存储程序和信息，工作时把信息读取出来，然后发出指令，这样的话机器人可以重复的根据人当时示教的结果，再现出这种动作，比方说汽车的点焊机器人，它只要把这个点焊的过程示教完以后，它总是重复这样一种工作，它对于外界的环境没有感知，这个力操作力的大小，这个工件存在不存在，焊的好与坏，它并不知道，那么实际上这种从第一代机器人，也就存在它这种缺陷，因此，在20世纪70年代后期，人们开始研究第二代机器人，叫带感觉的机器人，这种带感觉的机器人是类似人在某种功能的感觉，比如说力觉、触觉、滑觉、视觉、听觉和人进行相类比，有了各种各样的感觉，比方说在机器人抓一个物体的时候，它实际上力的大小能感觉出来，它能够通过视觉，能够去感受和识别它的形状、大小、颜色。抓一个鸡蛋，它能通过一个触觉，知道它的力的大小和滑动的情况。第三代机器人，也是我们机器人学中一个理想的所追求的最高级的阶段，叫智能机器人，那么只要告诉它做什么，不用告诉它怎么去做，它就能完成运动，感知思维和人机通讯的这种功能和机能，那么这个目前的发展还是相对的只是在局部有这种智能的概念和含义，但真正完整意义的这种智能机器人实际上并没有存在，而只是随着我们不断的科学技术的发展，智能的概念越来越丰富，它内涵越来越宽。

下边我简单介绍一下工业机器人的一些情况。到目前为止，工业机器人是最成熟，应用最广泛的一类机器人，世界总量目前已经销售110万台，这是1999年的统计，但这110万台在已经进行装备使用的是75万台，这个量也是不小的。总体情况看，日本在工业机器人这一块，是首位的，成为机器人的王国，美国发展也很迅速，目前在新安装的台数方面，已经超过了日本，中国刚开始进入产业化的阶段，已经研制出多种工业机器人样机，已有小批量在生产中使用。

点焊机器人主要是针对汽车生产线，提高生产效率，提高汽车焊接的质量，降低工人的劳动强度的一种机器人。它的特点是通过机器人对两个钢板进行点焊的时候，需要承载一个很大的焊钳，一般在几十公斤以上，那么它的速度要求在每秒钟一米五到两米这样的高速运动，所以它一般来说有五到六个自由度，负载三十到一百二十公斤，工作的空间很大，大概有两米，这样一个球形的工作空间，运动速度也很高，那么自由度的概念，就是说，是相对独立运动的部件的个数，就相当于我们人体，腰是一个回转的自由度，我们大臂可以抬起来，小臂可以弯曲，那么这就三个自由度，同时腕部还有一个调整姿态来使用的三个自由度，所以一般的机器人有六个自由度，就能把空间的三个位置，三个姿态，机器人完全实现，当然也有小于六个自由度的，也有多于六个自由度的机器人，只是在不同的需要场合来配置。

第二类是服务机器人，随着工业化的发展，尤其近十年以来，机器人的发展的应用领域在不断拓宽，目前一个很重要的特征，大家都知道，机器人已经从制造业逐渐转向了非制造业和服务行业，刚才谈的汽车制造属于是制造业，但服务行业包括清洁、加油、救护、抢险、救灾这些等等，都属于非制造行业和服务行业，那么这里边跟工业机器人相比，它有一个很重要的不同，它主要是一个移动平台，它能够移动、去运动，上面有一些手臂进行操作，同时还装有一些像力觉传感器和视觉传感器、超声测距传感器等等。它对周边的环境进行识别，来判断它的运动，完成某种工作，这是服务机器人的基本的一个特点。

例如，家务机器人主要体现在像一些对地毯和地板定期的它能够进行清扫和吸尘，它这个机器人很有意思，它有传感器，它能够把家具和人能识别出来，它自动的按照一种规律，能根据路径把地面全部的清扫干净，这也是家务中一些机器人的表现。

那么医疗机器人，是近五年来发展比较迅速的一个新的应用领域。如果人手术的时候，医生来手术，一个是疲劳，另一个人手操作的精度还是有限的。在德国一些大学里面，面向人的脊椎，如腰间盘突出这种病，进行识别以后，能够自动地用机器人来辅助进行定位，进行操作和手术。像美国已经有一千多例机器人对人眼球进行手术，这样的机器人，还包括通过遥控操作的办法，实现对人的胃肠这种手术，大家在电视里边看到，一个机械手，大概有手指这样粗细的一个机械手，通过插入腹脏以后，人在屏幕上操作这个机器手，同时对它用激光的方法对病灶进行激光的治疗，这样的话，人就不用很大幅度地破坏人的身体，这实际对人的一种解放，是非常好一种机器人，医疗机器人它也很复杂，一方面它完全自动去完成各种工作，是有困难的，一般来说都是人来参与，这是美国开发的一个林白手术这样一个例子，人通过在屏幕上，通过一个遥控操作手来控制另一个机械手，实现通过对人的腹腔进行手术，前几年我们国家展览会上，美国已经成功的实现了对人的心脏瓣膜的手术和搭桥手术，这已经在机器人领域中，引起了很大的轰动，还包括，AESOP的这种外科手术机器人，它实际上通过一些仪器能够对人的一些病变进行检查，通过一个机械手就能够实现对人的某些部位进行手术，还包括遥操作机械手，以及多个医生可以在机器人共同参与下进行手术，包括机器人给大夫医生拿钳子、镊子或刀子来代替护士的工作，同时把照明能够自动的给医生的动作联系起来，医生的手到哪儿，照明就去哪儿，这样非常好的，一个医生的助手。

机器人是人类的得力助手，能友好相处的可靠朋友，将来我们会看到人和机器人会存在一个空间里边，成为一个互相的助手和朋友。机器人会不会产生饭碗的问题。我们相信不会出现“机器人上岗，工人下岗”的局面，因为人们随着社会的发展，实际上把人们从繁重的体力和危险的环境中解放出来，使人们有更好的岗位去工作，去创造更好的精神财富和文化财富。

第四篇：中英文翻译

Fundamentals This chapter describes the fundamentals of today’s wireless communications.First a detailed description of the radio channel and its modeling are presented, followed by the introduction of the principle of OFDM multi-carrier transmission.In addition, a general overview of the spread spectrum technique, especially DS-CDMA, is given and examples of potential applications for OFDM and DS-CDMA are analyzed.This introduction is essential for a better understanding of the idea behind the combination of OFDM with the spread spectrum technique, which is briefly introduced in the last part of this chapter.1.1 Radio Channel Characteristics Understanding the characteristics of the communications medium is crucial for the appropriate selection of transmission system architecture, dimensioning of its components, and optimizing system parameters, especially since mobile radio channels are considered to be the most difficult channels, since they suffer from many imperfections like multipath fading, interference, Doppler shift, and shadowing.The choice of system components is totally different if, for instance, multipath propagation with long echoes dominates the radio propagation.Therefore, an accurate channel model describing the behavior of radio wave propagation in different environments such as mobile/fixed and indoor/outdoor is needed.This may allow one, through simulations, to estimate and validate the performance of a given transmission scheme in its several design phases.1.1.1 Understanding Radio Channels In mobile radio channels(see Figure 1-1), the transmitted signal suffers from different effects, which are characterized as follows: Multipath propagation occurs as a consequence of reflections, scattering, and diffraction of the transmitted electromagnetic wave at natural and man-made objects.Thus, at the receiver antenna, a multitude of waves arrives from many different directions with different delays, attenuations, and phases.The superposition of these waves results in amplitude and phase variations of the composite received signal.Doppler spread is caused by moving objects in the mobile radio channel.Changes in the phases and amplitudes of the arriving waves occur which lead to time-variant multipath propagation.Even small movements on the order of the wavelength may result in a totally different wave superposition.The varying signal strength due to time-variant multipath propagation is referred to as fast fading.Shadowing is caused by obstruction of the transmitted waves by, e.g., hills, buildings, walls, and trees, which results in more or less strong attenuation of the signal strength.Compared to fast fading, longer distances have to be covered to significantly change the shadowing constellation.The varying signal strength due to shadowing is called slow fading and can be described by a log-normal distribution [36].Path loss indicates how the mean signal power decays with distance between transmitter and receiver.In free space, the mean signal power decreases with the square of the distance between base station(BS)and terminal station(TS).In a mobile radio channel, where often no line of sight(LOS)path exists, signal power decreases with a power higher than two and is typically in the order of three to five.Variations of the received power due to shadowing and path loss can be efficiently counteracted by power control.In the following, the mobile radio channel is described with respect to its fast fading characteristic.1.1.2 Channel Modeling The mobile radio channel can be characterized by the time-variant channel impulse response h(τ , t)or by the time-variant channel transfer function H(f, t), which is the Fourier transform of h(τ , t).The channel impulse response represents the response of the channel at time t due to an impulse applied at time t − τ.The mobile radio channel is assumed to be a wide-sense stationary random process, i.e., the channel has a fading statistic that remains constant over short periods of time or small spatial distances.In environments with multipath propagation, the channel impulse response is composed of a large number of scattered impulses received over Np different paths，Where

and ap, fD,p, ϕp, and τp are the amplitude, the Doppler frequency, the phase, and the propagation delay, respectively, associated with path p, p = 0,..., Np − 1.The assigned channel transfer function is

The delays are measured relative to the first detectable path at the receiver.The Doppler Frequency

depends on the velocity v of the terminal station, the speed of light c, the carrier frequency fc, and the angle of incidence αp of a wave assigned to path p.A channel impulse response with corresponding channel transfer function is illustrated in Figure 1-2.The delay power density spectrum ρ(τ)that characterizes the frequency selectivity of the mobile radio channel gives the average power of the channel output as a function of the delay τ.The mean delay τ , the root mean square(RMS)delay spread τRMS and the maximum delay τmax are characteristic parameters of the delay power density spectrum.The mean delay is

Where

Figure 1-2 Time-variant channel impulse response and channel transfer function with frequency-selective fading is the power of path p.The RMS delay spread is defined as Similarly, the Doppler power density spectrum S(fD)can be defined that characterizes the time variance of the mobile radio channel and gives the average power of the channel output as a function of the Doppler frequency fD.The frequency dispersive properties of multipath channels are most commonly quantified by the maximum occurring Doppler frequency fDmax and the Doppler spread fDspread.The Doppler spread is the bandwidth of the Doppler power density spectrum and can take on values up to two times |fDmax|, i.e.，1.1.3Channel Fade Statistics The statistics of the fading process characterize the channel and are of importance for channel model parameter specifications.A simple and often used approach is obtained from the assumption that there is a large number of scatterers in the channel that contribute to the signal at the receiver side.The application of the central limit theorem leads to a complex-valued Gaussian process for the channel impulse response.In the absence of line of sight(LOS)or a dominant component, the process is zero-mean.The magnitude of the corresponding channel transfer function

is a random variable, for brevity denoted by a, with a Rayleigh distribution given by

Where

is the average power.The phase is uniformly distributed in the interval [0, 2π].In the case that the multipath channel contains a LOS or dominant component in addition to the randomly moving scatterers, the channel impulse response can no longer be modeled as zero-mean.Under the assumption of a complex-valued Gaussian process for the channel impulse response, the magnitude a of the channel transfer function has a Rice distribution given by

The Rice factor KRice is determined by the ratio of the power of the dominant path to thepower of the scattered paths.I0 is the zero-order modified Bessel function of first kind.The phase is uniformly distributed in the interval [0, 2π].1.1.4Inter-Symbol(ISI)and Inter-Channel Interference(ICI)The delay spread can cause inter-symbol interference(ISI)when adjacent data symbols overlap and interfere with each other due to different delays on different propagation paths.The number of interfering symbols in a single-carrier modulated system is given by

For high data rate applications with very short symbol duration Td < τmax, the effect of ISI and, with that, the receiver complexity can increase significantly.The effect of ISI can be counteracted by different measures such as time or frequency domain equalization.In spread spectrum systems, rake receivers with several arms are used to reduce the effect of ISI by exploiting the multipath diversity such that individual arms are adapted to different propagation paths.If the duration of the transmitted symbol is significantly larger than the maximum delay Td τmax, the channel produces a negligible amount of ISI.This effect is exploited with multi-carrier transmission where the duration per transmitted symbol increases with the number of sub-carriers Nc and, hence, the amount of ISI decreases.The number of interfering symbols in a multi-carrier modulated system is given by

Residual ISI can be eliminated by the use of a guard interval(see Section 1.2).The maximum Doppler spread in mobile radio applications using single-carrier modulation is typically much less than the distance between adjacent channels, such that the effect of interference on adjacent channels due to Doppler spread is not a problem for single-carrier modulated systems.For multi-carrier modulated systems, the sub-channel spacing Fs can become quite small, such that Doppler effects can cause significant ICI.As long as all sub-carriers are affected by a common Doppler shift fD, this Doppler shift can be compensated for in the receiver and ICI can be avoided.However, if Doppler spread in the order of several percent of the sub-carrier spacing occurs, ICI may degrade the system performance significantly.To avoid performance degradations due to ICI or more complex receivers with ICI equalization, the sub-carrier spacing Fs should be chosen as

such that the effects due to Doppler spread can be neglected(see Chapter 4).This approach corresponds with the philosophy of OFDM described in Section 1.2 and is followed in current OFDM-based wireless standards.Nevertheless, if a multi-carrier system design is chosen such that the Doppler spread is in the order of the sub-carrier spacing or higher, a rake receiver in the frequency domain can be used [22].With the frequency domain rake receiver each branch of the rake resolves a different Doppler frequency.1.1.5Examples of Discrete Multipath Channel Models Various discrete multipath channel models for indoor and outdoor cellular systems with different cell sizes have been specified.These channel models define the statistics of the 5 discrete propagation paths.An overview of widely used discrete multipath channel models is given in the following.COST 207 [8]: The COST 207 channel models specify four outdoor macro cell propagation scenarios by continuous, exponentially decreasing delay power density spectra.Implementations of these power density spectra by discrete taps are given by using up to 12 taps.Examples for settings with 6 taps are listed in Table 1-1.In this table for several propagation environments the corresponding path delay and power profiles are given.Hilly terrain causes the longest echoes.The classical Doppler spectrum with uniformly distributed angles of arrival of the paths can be used for all taps for simplicity.Optionally, different Doppler spectra are defined for the individual taps in [8].The COST 207 channel models are based on channel measurements with a bandwidth of 8–10 MHz in the 900-MHz band used for 2G systems such as GSM.COST 231 [9] and COST 259 [10]: These COST actions which are the continuation of COST 207 extend the channel characterization to DCS 1800, DECT, HIPERLAN and UMTS channels, taking into account macro, micro, and pico cell scenarios.Channel models with spatial resolution have been defined in COST 259.The spatial component is introduced by the definition of several clusters with local scatterers, which are located in a circle around the base station.Three types of channel models are defined.The macro cell type has cell sizes from 500 m up to 5000 m and a carrier frequency of 900 MHz or 1.8 GHz.The micro cell type is defined for cell sizes of about 300 m and a carrier frequency of 1.2 GHz or 5 GHz.The pico cell type represents an indoor channel model with cell sizes smaller than 100 m in industrial buildings and in the order of 10 m in an office.The carrier frequency is 2.5 GHz or 24 GHz.COST 273: The COST 273 action additionally takes multi-antenna channel models into account, which are not covered by the previous COST actions.CODIT [7]: These channel models define typical outdoor and indoor propagation scenarios for macro, micro, and pico cells.The fading characteristics of the various propagation environments are specified by the parameters of the Nakagami-m distribution.Every environment is defined in terms of a number of scatterers which can take on values up to 20.Some channel models consider also the angular distribution of the scatterers.They have been developed for the investigation of 3G system proposals.Macro cell channel type models have been developed for carrier frequencies around 900 MHz with 7 MHz bandwidth.The micro and pico cell channel type models have been developed for carrier frequencies between 1.8 GHz and 2 GHz.The bandwidths of the measurements are in the range of 10–100 MHz for macro cells and around 100 MHz for pico cells.JTC [28]: The JTC channel models define indoor and outdoor scenarios by specifying 3 to 10 discrete taps per scenario.The channel models are designed to be applicable for wideband digital mobile radio systems anticipated as candidates for the PCS(Personal Communications Systems)common air interface at carrier frequencies of about 2 GHz.UMTS/UTRA [18][44]: Test propagation scenarios have been defined for UMTS and UTRA system proposals which are developed for frequencies around 2 GHz.The modeling of the multipath propagation corresponds to that used by the COST 207 channel models.HIPERLAN/2 [33]: Five typical indoor propagation scenarios for wireless LANs in the 5 GHz frequency band have been defined.Each scenario is described by 18discrete taps of the delay power density spectrum.The time variance of the channel(Doppler spread)is modeled by a classical Jake’s spectrum with a maximum terminal speed of 3 m/h.Further channel models exist which are, for instance, given in [16].1.1.6Multi-Carrier Channel Modeling Multi-carrier systems can either be simulated in the time domain or, more computationally efficient, in the frequency domain.Preconditions for the frequency domain implementation are the absence of ISI and ICI, the frequency nonselective fading per sub-carrier, and the time-invariance during one OFDM symbol.A proper system design approximately fulfills these preconditions.The discrete channel transfer function adapted to multi-carrier signals results in

where the continuous channel transfer function H(f, t)is sampled in time at OFDM symbol rate s and in frequency at sub-carrier spacing Fs.The duration

s is the total OFDM symbol duration including the guard interval.Finally, a symbol transmitted onsub-channel n of the OFDM symbol i is multiplied by the resulting fading amplitude an,i and rotated by a random phase ϕn,i.The advantage of the frequency domain channel model is that the IFFT and FFT operation for OFDM and inverse OFDM can be avoided and the fading operation results in one complex-valued multiplication per sub-carrier.The discrete multipath channel models introduced in Section 1.1.5 can directly be applied to(1.16).A further simplification of the channel modeling for multi-carrier systems is given by using the so-called uncorrelated fading channel models.1.1.6.1Uncorrelated Fading Channel Models for Multi-Carrier Systems These channel models are based on the assumption that the fading on adjacent data symbols after inverse OFDM and de-interleaving can be considered as uncorrelated [29].This assumption holds when, e.g., a frequency and time interleaver with sufficient interleaving depth is applied.The fading amplitude an,i is chosen from a distribution p(a)according to the considered cell type and the random phase ϕn,I is uniformly distributed in the interval [0,2π].The resulting complex-valued channel fading coefficient is thus generated independently for each sub-carrier and OFDM symbol.For a propagation scenario in a macro cell without LOS, the fading amplitude an,i is generated by a Rayleigh distribution and the channel model is referred to as an uncorrelated Rayleigh fading channel.For smaller cells where often a dominant propagation component occurs, the fading amplitude is chosen from a Rice distribution.The advantages of the uncorrelated fading channel models for multi-carrier systems are their simple implementation in the frequency domain and the simple reproducibility of the simulation results.1.1.7Diversity The coherence bandwidth of a mobile radio channel is the bandwidth over which the signal propagation characteristics are correlated and it can be approximated by

The channel is frequency-selective if the signal bandwidth B is larger than the coherence bandwidth.On the other hand, if B is smaller than , the channel is frequency nonselective or flat.The coherence bandwidth of the channel is of importance for evaluating the performance of spreading and frequency interleaving techniques that try to exploit the inherent frequency diversity Df of the mobile radio channel.In the case of multi-carrier transmission, frequency diversity is exploited if the separation of sub-carriers transmitting the same information exceeds the coherence bandwidth.The maximum achievable frequency diversity Df is given by the ratio between the signal bandwidth B and the coherence bandwidth，The coherence time of the channel is the duration over which the channel characteristics can be considered as time-invariant and can be approximated by

If the duration of the transmitted symbol is larger than the coherence time, the channel is time-selective.On the other hand, if the symbol duration is smaller than , the channel is time nonselective during one symbol duration.The coherence time of the channel is of importance for evaluating the performance of coding and interleaving techniques that try to exploit the inherent time diversity DO of the mobile radio channel.Time diversity can be exploited if the separation between time slots carrying the same information exceeds the coherence time.A number of Ns successive time slots create a time frame of duration Tfr.The maximum time diversity Dt achievable in one time frame is given by the ratio between the duration of a time frame and the coherence time, A system exploiting frequency and time diversity can achieve the overall diversity

The system design should allow one to optimally exploit the available diversity DO.For instance, in systems with multi-carrier transmission the same information should be transmitted on different sub-carriers and in different time slots, achieving uncorrelated faded replicas of the information in both dimensions.Uncoded multi-carrier systems with flat fading per sub-channel and time-invariance during one symbol cannot exploit diversity and have a poor performance in time and frequency selective fading channels.Additional methods have to be applied to exploit diversity.One approach is the use of data spreading where each data symbol is spread by a spreading code of length L.This, in combination with interleaving, can achieve performance results which are given for

by the closed-form solution for the BER for diversity reception in Rayleigh fading channels according to [40]

Whererepresents the combinatory function，and σ2 is the variance of the noise.As soon as the interleaving is not perfect or the diversity offered by the channel is smaller than the spreading code length L, or MCCDMA with multiple access interference is applied,(1.22)is a lower bound.For L = 1, the performance of an OFDM system without forward error correction(FEC)is obtained, 9

which cannot exploit any diversity.The BER according to(1.22)of an OFDM(OFDMA, MC-TDMA)system and a multi-carrier spread spectrum(MC-SS)system with different spreading code lengths L is shown in Figure 1-3.No other diversity techniques are applied.QPSK modulation is used for symbol mapping.The mobile radio channel is modeled as uncorrelated Rayleigh fading channel(see Section 1.1.6).As these curves show, for large values of L, the performance of MC-SS systems approaches that of an AWGN channel.Another form of achieving diversity in OFDM systems is channel coding by FEC, where the information of each data bit is spread over several code bits.Additional to the diversity gain in fading channels, a coding gain can be obtained due to the selection of appropriate coding and decoding algorithms.中文翻译 1基本原理

这章描述今日的基本面的无线通信。第一一个的详细说明无线电频道，它的模型被介绍，跟随附近的的介绍的原则的参考正交频分复用多载波传输。此外，一个一般概观的扩频技术，尤其ds-cdma，被给，潜力的例子申请参考正交频分复用，DS对1。分配的通道传输功能是

有关的延误测量相对于第一个在接收器检测到的路径。多普勒频率

取决于终端站，光速c，载波频率fc的速度和发病路径分配给速度v波αp角度页具有相应通道传输信道冲激响应函数图1-2所示。

延迟功率密度谱ρ（τ）为特征的频率选择性移动无线电频道给出了作为通道的输出功能延迟τ平均功率。平均延迟τ，均方根（RMS）的时延扩展τRMS和最大延迟τmax都是延迟功率密度谱特征参数。平均时延特性参数为

有

图1-2时变信道冲激响应和通道传递函数频率选择性衰落是权力页的路径均方根时延扩展的定义为 同样，多普勒频谱的功率密度（FD）的特点可以定义

在移动时变无线信道，并给出了作为一种金融衍生工具功能的多普勒频率通道输出的平均功率。多径信道频率分散性能是最常见的量化发生的多普勒频率和多普勒fDmax蔓延fDspread最大。多普勒扩散是功率密度的多普勒频谱带宽，可价值观需要两年时间| fDmax|，即

1.1.3频道淡出统计

在衰落过程中的统计特征和重要的渠道是信道模型参数规格。一个简单而经常使用的方法是从假设有一个通道中的散射，有助于在大量接收端的信号。该中心极限定理的应用导致了复杂的值的高斯信道冲激响应过程。在对视线（LOS）或线的主要组成部分的情况下，这个过程是零的意思。相应的通道传递函数幅度

是一个随机变量，通过给定一个简短表示由瑞利分布，有

是的平均功率。相均匀分布在区间[0，2π]。

在案件的多通道包含洛杉矶的或主要组件除了随机移动散射，通道脉冲响应可以不再被建模为均值为零。根据信道脉冲响应的假设一个复杂的值高斯过程，其大小通道的传递函数A的水稻分布给出

赖斯因素KRice是由占主导地位的路径权力的威力比分散的路径。I0是零阶贝塞尔函数的第一阶段是一致kind.The在区间[0，2π]分发。

1.1.4符号间（ISI）和通道间干扰（ICI）

延迟的蔓延引起的符号间干扰（ISI）当相邻的数据符号上的重叠与互相不同的传播路径，由于不同的延迟干涉。符号的干扰在单载波调制系统的号码是给予

对于高数据符号持续时间很短运输署<蟿MAX时，ISI的影响，这样一来，速率应用，接收机的复杂性大大增加。对干扰影响，可以抵消，如时间或频域均衡不同的措施。在扩频系统，与几个臂Rake接收机用于减少通过利用多径分集等，个别武器适应不同的传播路径的干扰影响。

如果发送符号的持续时间明显高于大的最大延迟运输署蟿最大，渠道产生ISI的微不足道。这种效果是利用多载波传输的地方，每发送符号的增加与子载波数控数目，因此，ISI的金额减少的持续时间。符号的干扰多载波调制系统的号码是给予

可以消除符号间干扰由一个保护间隔（见1.2节）的使用。

最大多普勒在移动无线应用传播使用单载波调制通常比相邻通道，这样，干扰对由于多普勒传播相邻通道的作用不是一个单载波调制系统的问题距离。对于多载波调制系统，子通道间距FS可以变得非常小，这样可以造成严重的多普勒效应ICI的。只要所有子载波只要是一个共同的多普勒频移金融衍生工具的影响，这可以补偿多普勒频移在接收器和ICI是可以避免的。但是，如果在对多普勒子载波间隔为几个百分点的蔓延情况，卜内门可能会降低系统的性能显着。为了避免性能降级或因与ICI卜内门更复杂的接收机均衡，子载波间隔财政司司长应定为

这样说，由于多普勒效应可以忽略不扩散（见第4章）。这种方法对应于OFDM的1.2节中所述，是目前基于OFDM的无线标准遵循的理念。

不过，如果多载波系统的设计选择了这样的多普勒展宽在子载波间隔或更高，秩序是在频率RAKE接收机域名可以使用[22]。随着频域RAKE接收机每个支部耙解决了不同的多普勒频率。

1.1.5多径信道模型的离散的例子

各类离散多与不同的细胞大小的室内和室外蜂窝系统的信道模型已经被指定。这些通道模型定义的离散传播路径的统计信息。一种广泛使用的离散多径信道模型概述于下。造价207[8]：成本207信道模型指定连续四个室外宏蜂窝传播方案，指数下降延迟功率密度谱。这些频道功率密度的离散谱的实现都是通过使用多达12个频道。与6频道设置的示例列于表1-1。在这种传播环境的几个表中的相应路径延迟和电源配置给出。丘陵地形导致最长相呼应。

经典的多普勒频谱与均匀分布的到达角路径可以用于简化所有的频道。或者，不同的多普勒谱定义在[8]个人频道。207信道的成本模型是基于一个8-10兆赫的2G，如GSM系统中使用的900兆赫频段信道带宽的测量。造价231[9]和造价259[10]：这些费用是行动的延续成本207扩展通道特性到DCS1800的DECT，HIPERLAN和UMTS的渠道，同时考虑到宏观，微观和微微小区的情况为例。空间分辨率与已定义的通道模型在造价259。空间部分是介绍了与当地散射，这是在基站周围设几组圆的定义。三种类型的通道模型定义。宏细胞类型具有高达500〜5000米，载波频率为900兆赫或1.8 GHz的单元尺寸。微细胞类型被定义为细胞体积约300米，1.2 GHz或5 GHz载波频率。细胞类型代表的Pico与细胞体积小于100工业建筑物和办公室中的10 m阶米室内信道模型。载波频率为2.5 GHz或24千兆赫。造价273：成本273行动另外考虑到多天线信道模型，这是不是由先前的费用的行为包括在内。

CODIT [7]：这些通道模型定义的宏，微，微微蜂窝和室外和室内传播的典型案例。各种传播环境的衰落特性是指定的在NakagamiSS）的不同扩频码L是长度，如图1-3所示的系统。没有其他的分集技术被应用。QPSK调制用于符号映射。移动无线信道建模为不相关瑞利衰落信道（见1.1.6）。由于这些曲线显示，办法，AWGN信道的一对L时，对MC-SS系统性能有很大价值。

另一种实现形式的OFDM系统的多样性是由前向纠错信道编码，在这里，每个数据位的信息分散在几个代码位。附加在衰落信道分集增益，编码增益一个可因适当的编码和解码算法的选择。

第五篇：中英文翻译

蓄电池 battery 充电 converter 转换器 charger

开关电器 Switch electric 按钮开关 Button to switch 电源电器 Power electric 插头插座 Plug sockets