篇一：本科毕业设计文献翻译
中文翻译
2．1理想蜂窝小区的覆盖范围
根据标准传播模型SPM，各个地区针对不同的无线信号频段分别进行传播模型校正，得到较适合该地区该频段的传播模型：
d表示接收机与基站间的距离；HT x为发射机高度；HRx为接收机高度；DiffLoss表示散射造成的路径损耗；f(clutter)表示各个clutter损耗的加权平均，表示为Kc。
通常情况下，一个区域内的移动终端接收电平在-85dBm以上，可以认为该区域有较良好的无线网络覆盖。因此蜂窝基站小区覆盖边界处的接收电平为-85dBm、平均天线口发射
功率51dBm来推算理论覆盖范围。
2．2 GSM理论网络容量与载干比C/I间的计算方法
载干比C/I通常被用来衡量GSM网络的移动通话质量若使用MRP（多重频率复用方式）来进行频率规划的话，则理论计算规划可实现的C/I，可以应用以下的公式大致推算出：
其中a表示传播模型中的路径损耗斜率；D表示相邻2个小区群中位置相对应的2个小区中心之间的距离，即最近同频小区距离，也称为频率复用距离；R为小区六边形外接圆半径，即小区覆盖半径；Ki为传播条件、天线方向去耦、天线下倾等因素的综合修正因子（建议取值范围为-5~0）。针对一个地区具体的网络a和Ki为相对固定的值。
2．3 GSM系统网络容量与无线通话质量间的关系
GSM网络无线通话质量的主要衡量标准为载干比C/I，当一块区域的GSM网络载干比C/I>9dB时，可以认为该区域拥有较好无线通话质量。从章节2.2中的公式中得到推论，在一个确定的无线环境中，蜂窝小区连续均匀覆盖，即小区的覆盖距离为定值，若载干比C/I值恒定，则GSM理论网络容量与可用载频数成正比。若GSM理论网络容量恒定，则载干比C/I值与可用载频数成正比。
3．2 COMMON BCCH技术
COMMON BCCH是双频共BTS的一种方式，利用DCS1800M的无线频率资源来补充GSM900M的单蜂窝扇区的载频数，从而实现容量上的增加。
开启双频标准小区功能有以下几方面特点：
（1）要求合理设计覆盖，使得同一扇区区内的不同载频有相同的覆盖；
（2）BCCH可以分配于任何一个频段，而不局限于低频段，单频手机只能接入到支持BCCH频段的载频上；
（3）由动态分配原则，语音或数据业务是被动态分配信道的，因此可以做到双频话务的自动均衡，而不像从前需通
过参数设置实现；
（4）GPRS或EDGE业务可以在两个频段上被同时分配，运营商可以简单通过业务层的设定允许非BCCH频段上的数据业务应用；
（5）不支持两个频段间的跳频；
（6）从AMR-FR到AMR-HR的切换可以在不同的频段内分别开启或关闭； 总而言之，开启共BCCH双频标准扇区功能使GSM900M和DCS1800M的载频在同一个扇区内工作，可以自然地实现双频话务均衡，提升了网络资源的利用率；同时，它只需设置一个频段的BCCH，为保持总配置不变可增加一个另频段的TCH载频，应对网络容量的增长需求。
在某GSM蜂窝基站中尝试使用COMMON BCCH技术，在GSM900M的蜂窝小区中增加DCS1800M的载频，将原先基站配置从7/7/6提升至16/14/11，其中GSM900M的频点数为
7/7/6，DCS1800M的频点数为9/7/5。
通过使用COMMON BCCH技术，GSM蜂窝基站的可用载频数大幅扩充，基站容量得到了提升。开启COMMON BCCH后该蜂窝小区的接通率、掉话率和切换成功率指标没有变化，接收电平指标有所提高，而语音质量指标差异变化不明显，因此使用COMMON BCCH技术的GSM蜂窝基站维持了较好的无线通话质量。
但是COMMON BCCH的开启对双频小区有覆盖一致的严格要求，在检测到好的主频信号却占上较弱的TCH信道，就可能引起切换和TCH分配成功率的下降，这对于室内通话情况，因为DCS1800信号的穿透损耗大，就变得更为明显。
文章来源
Michel Mouly and Mavie-Bernadeete Pauter：The GSM Systemfor Mobile Communications.
英文原文：
2.1 Ideal Cellular coverage
According to propagation model based on standard SPM, various regions of the radio signals of different frequencies correct the spread model ,which are more suited to the area of the band propagation model:
d is the distance between receiver and base station; HT x is the transmitter height; HRx is the receiver height; DiffLoss is scattering caused by the path loss; f (clutter) is the weighted average of all clutter loss, expressed as Kc.
Typically, a region of the mobile terminal receiving level above more than-85dBm can be considered good at wireless network coverage.
2. 2 calculated ways between GSM network capacity and carrier-to-interference ratio C / I
Carrier to interference C / I is often used to measure the quality of GSM network mobile calls. If use MRP (multi-frequency reuse method) to carry out frequency planning, planning can be calculated to achieve the C / I, the following formula can be applied to broadly calculate:
a is the path loss slop of propagation model; D is the distance between the centers of two neighboring cell groups, which the most closest distance between the same frequency district, also known as frequency reuse distance; R is radius semi-hexagonal circumcircle ,that cell coverage radius; Ki is conditions for the spread, the direction of decoupling the antenna, antenna tilt and other factors under the comprehensive correction factor (recommended values range from -5 to 0).
3. 2 COMMON BCCH Technology
COMMON BCCH frequency of BTS is a way of using DCS1800M of radio frequency resources to supplement GSM900M single-carrier frequency of the cellular sector in order to achieve the increase on capacity.
Opening cell functions of the dual standard obtains the following features:
(1) request the rational design of cover, making different frequency areas in the same sector covered by the same carrier;
(2) BCCH can be assigned to any one band, but not limited to low frequency, single-band mobile phone can only access to the support of BCCH carrier frequency band;
(3) According to the dynamic distribution principle, voice or data services are dynamically allocated channel. Therefore it can auto-balance dual-band, rather than before need parameter settings;
(4) GPRS or EDGE services can be assigned in two frequency bands at the same time, operators can simply set in the business layer to allow non-BCCH band data services on the application;
(5) Do not support frequency hopping between two bands;
(6) Switching from the AMR-FR to AMR-HR can be open or closed in different bands,
All in all, open standards for a total of BCCH dual band sector allows GSM900M and DCS1800M work in the same sector ,which can naturally realize the balance of the dual service and enhance the utilization of network resources; at the same time, it just setting one band of BCCH., in order to maintain the same overall configuration ,it increase TCH carrier frequency of the other bands to address growing demand for network capacity.
In a GSM cellular base station ,the attempt to use the COMMON BCCH technology add DCS1800M frequency in GSM900M cellular district, and upgrade the original base station configuration from 7/7/6 to 16/14/11,when points to the frequency of GSM900M is 7/7/6, 9/7/5 for DCS1800M frequency points.
Through the use of COMMON BCCH Technology, the number of the carrier frequency of GSM cellular base stations can be significantly expanded,and base station capacity has been improved. After opening COMMON BCCH, the Cellular's switch rate, drop call rate and indicators of the success rate of switching have no change, the indicator level of receiver increasing, while the difference in voice quality indicators did not change significantly, so the use of COMMON BCCH technology makes GSM cellular base station to maintain good wireless call quality.
But COMMON BCCH's open has strict requirements on the same frequency coverage of dual area. because good frequency accounting for the weaker TCH channel may cause switch and decline of TCH allocation success rate.If the situation calls for indoor situation, because the DCS1800 signals through loss is large, it becomes more evident.
篇二：PLC建筑电梯控制系统中英文外文翻译文献
(文档含英文原文和中文翻译)
中英文资料翻译
Application of PLC in the Elevator Control System of
Intelligence Building
Abstract: The paper mainly discusses one subsystem of intelligence building system: the elevator control system. The PLC strong ability in interference and so on makes the elevator industry one after another to apply the PLC to the elevator control system in order to replace the relay being used in traditional elevator control system. The Application of PLC in the Elevator control system reduces the breakdown rate and efficiently improves the operating reliability of the elevator with safety .The structure of system is also simple and tightly packed.The working principle of the elevator control system is: The spot control information is send into the ＰＬＣ from the
customer input devices firstly, then the PLC control cabinet is required to send out the control signal to drive the equipments according to the system demands. The elevator can then proceed the homologous action according to the control request .The paper selectsＯＭＲＯＮ company’s Ｃ200HE series PLC, introducing parts of signal hookup of the elevator control system and explaining the function of the control cabinet. Lastly the automation programming is introduced. Simulated experiments enunciates that the design method is viable. It can make the personnel of the industry management center to long-distance monitor and control the elevator in control center, to connect the elevator control system with intelligence building industry management system by Ethernet or special-purpose network such as Lon Works.The elevator working state can also be timely watched.These not only can realize scientific centralized management of the elevator, but also can lower the elevator maintenance cost etc. It is one of the developing direction of intelligence building elevator control system.
Keywords: PLC; intelligence building; elevator control system; working principle; program design
Ⅰ. Introduction
In 1980s The first intelligence mansion had been completed in America, then intelligence building has been abroadly taken attentions by the whole world.The concept of intelligence building has been put different meanings along with the development of society. The early stage intelligence building had been thought that it is equal to the intelligent mansion, but now the intelligence building not only includes the intelligence mansions but also involves intelligence residential districts. This paper mainly discusses one subsystem of intelligence building system: the elevator control system.
In intelligence residential districts the enterprise’s information managing system mainly takes charge of the things which related to the daily life, for example supervising the district equipments, managing vehicles, disposing critical situations and so on.The elevator supervising and control system is also necessary to the
intelligence residential districts.How to make people feel safe ,stable and comfortable and how to save energy resources and protect environments and so on are the basic requirements to the elevator control system.
PLC is a common industry control device.It is a special industry control computer which has the perfect function and simple frame. The PLC strong ability in interference and so on makes the elevator industry one after another to apply the PLC to the elevator control system, in order to replace the relay being used in traditional elevator control system. The Application of PLC in the elevator control system reduces the breakdown rate and efficiently improves the operating reliability of the elevator with safety. This paper mainly discusses the elevator control system’s working principles, the system’s software and hardware realization methods and so on.
Ⅱ. The Working Principle of Elevator Control System
In Fig. 1 the Hardware Structure Graph of Elevator Control System is presented.
Fig. 1 The Hardware Structure Graph of Elevator Control System
The Working Principles of Elevator Control System are stated as follows: The spot control information is send into the PLC from the customer input devices firstly, then the PLC control cabinet is required to send out the control signal to drive the equipments according to the system demands. The elevator can then perform the homologous action according to the control request. There are velocity feedback devices in system, which adopt measure velocity generators to provide the elevator
velocities and generally are installed in the tail of tow motors .So this is a feedback control system, which can improve the system’s control precision.
Ⅲ. The Hardware Configuration of Control System
It is not necessary to do interface circuit in the elevator’s PLC control system.What we should do is to send the signals to PLC digital input terminals.The signals include inside and outside calling signals ,floor location inspecting signals , limiting location signals ,opening and shutdown the elevator door signals etc. The DC power which is provided to PLC can be used as indicator light power. The PLC output points can be directly used to control transducers for the purpose of electrical motor’s positive turn and reverse ,stop and control each segment velocity and so on .ＯＭＲＯＮ company’s Ｃ200HE series PLC has been selected as major control configuration according to the input/output points and the length of user’s program. On the other hand we also consider that the system’s function can be expanded in the future .Ｃ200HE series PLC ,whose perfect function and strong reliability, can meet these demands at present.
Moreover, input and output devices are needed in elevator control system, besides the PLC, system’s major control device.
Part of signal hookups of the elevator electric control system is shown in Fig.2. The control cabinet is the control center, from which we can send out various control commands. The control cabinet often was installed in the elevator room .The electric devices and signal systems, for example the contactors, relays, capacitances, resistors, rectifiers and transformers etc., are centralized in the control cabinet. The Power of the control cabinet was imported from the chief power of the elevator room. This power was also introduced into control panel by soft cables and was linked with each control buttons. The power lines which was derived from control cabinet was delivered to tow electric motors. Others control lines and signal lines were separately sent to each floor junction
Ⅳ. Program design
The design includes two parts: hardware and software.The hardware design is the base of software. Considering that the control demands are relatively complex, we design the programs separately according to the control function. Furthermore, we follow the principle as follows: When the elevator is ascending, the ascending demands are prior to other demands; When the elevator is descending, the descending demands are prior to other demands. The Sequential Function Chart (SFC) is adopted during the boxes to form elevator’s executive circuitry design. It is a method specially used in industrial sequential control. The SFC method can describe the system’s working procedure in great detail. For example there is a three layers intelligence building. A subprogram, the calling from the third floor as elevator in the first floor, is shown in Fig. 3 with SFC.
篇三：PLC毕业设计相关英文文献翻译
翻译对应文章Introduction to digital temperature sensor DS1820
数字温度传感器DS1820的介绍
特性：
·独特的单线接口，只需1 个接口引脚即可通信；
·多点（multidrop）能力使分布式温度检测应用得以简化；
·不需要外部元件；
·可用数据线供电；
·不需备份电源；
·测量范围从-55至+125℃，增量值为0.5℃。等效的华氏温度范围是-67 F 至257 F，增量值为0.9 F；
·以9位数字值方式读出温度；
·在1秒（典型值）内把温度变换为数字；
·用户可定义的，非易失性的温度告警设置；
·告警搜索命令识别和寻址温度在编定的极限之外的器件（温度告警情况）； ·应用范围包括恒温控制，工业系统，消费类产品，温度计或任何热敏系统。
详细说明
DS1820有三个主要的数据部件：1）64位激光lasered ROM；2）温度灵敏元件，和3）非易失性温度告警触发器TH和TL。器件从单线的通信线取得其电源，在信号线为高电平的时间周期内，把能量贮存在内部的电容器中，在单信号线为低电平的时间期内断开此电源，直到信号线变为高电平重新接上寄生（电容）电源为止。作为另一种可供选择的方法，DS1820也可以用外部5V电源供电。与DS1820 的通信经过一个单线接口。在单线接口情况下，在ROM 操作未定建立之前不能使用存贮器和控制操作。主机必须首先提供五种ROM操作命令之一；
1）Read ROM(读ROM)；
2)Match ROM(符合ROM)；
3)Search ROM(搜索ROM)；
4)Skip ROM(跳过ROM)；
5）Alarm Search(告警搜索)；
这些命令对每一器件的64位激光ROM 部分进行操作，如果在单线上有许多器件，那么可以挑选出一个特定的器件，并给总线上的主机指示存在多少器件及其类型。在成功地执行了ROM 操作序列之后，可使用存贮器和控制操作，然后主机可以提供六种存贮器和控制操作命令之一。
一个控制操作命令指示DS1820 完成温度测量。该测量的结果将放入DS1820 的高速暂存（便笺式）存贮器（Scratchpad memory），通过发出读暂存存储器内容的存储器操作命令可以读出此结果。每一温度告警触发器TH和TL构成一个字节的EEPROM。如果不对DS1820 施加告警搜索命令，这些寄存器可用作通用用户存储器使用存储器，操作命令可以写TH 和TL 对这些寄存器的读访问。所有数据均以最低有效位在前的方式被读写。
寄生电源
方框图(图1)示出寄生电源电路。当I/O或VDD 引脚为高电平时，这个电路便“取”得电源。只要符合指定的定时和电压要求，I/O将提供足够的功率（标题为“单总线系统”一节）。寄生电源的优点是双重的：
1）利用此引脚，远程温度检测无需本地电源；
2）缺少正常电源条件下也可以读ROM；
为了使DS1820能完成准确的温度变换，当温度变换发生时，I/O 线上必须提供足够的功率。因为DS1820 的工作电流高达1mA ，5K 的上拉电阻将使I/O 线没有足够的驱动能力。如果几个SD1820 在同一条I/O 线上而且同时变换，那么这一问题将变得特别尖锐。
有两种方法确保DS1820 在其有效变换期内得到足够的电源电流。第一种方法是发生温度变换时，在I/O 线上提供一强的上拉。如图2所示，通过使用一个MOSFET 把I/O 线直接拉到电源可达到这一点。当使用寄生电源方式时VDD 引脚必须连接到地。
向DS1820 供电的另外一种方法是通过使用连接到VDD 引脚的外部电源，如图3 所示这种方法的优点是在I/O 线上不要求强的上拉。总线上主机不需向上连接便在温度变换期间使线保持高电平。这就允许在变换时间内其它数据在单线上传送。此外，在单线总线上可以放置任何数目的DS1820 ，而且如果它们都使用外部电源，那么通过发出跳过（Skip） ROM 命令和接着发出变换（Convert） T 命令，可以同时完成温度变换。注意只要外部电源处于工作状态，GND（地引）脚不可悬空。
在总线上主机不知道总线上DS1820 是寄生电源供电还是外部VDD 供电的情况下，在DS1820 内采取了措施来通知采用的供电方案。总线上主机通过发出跳过（Skip）ROM 的操作约定，然后发出读电源命令，可以决定是否有需要强上拉的DS1820 在总线上。在此命令发出后，主机接着发出读时间片。如果是寄生供电，DS1820 将在单线总线上送回“0”；如果由VDD 引脚供电，它将送回1。如果主机接收到一个“0”，它知道它必须在温度变换期间在I/O 线上供一个强的上拉。有关此命令约定的详细说明见存贮器命令功能一节。
运用——测量温度
SDS1820 通过使用在板（on-board）温度测量专利技术来测量温度。温度测量电路的方框图见图4 所示。
DS1820 通过门开通期间内低温度系数振荡器经历的时钟周期个数计数来测量温度，如果在门开通期结束前计数器达到零，那么温度寄存器—它也被予置到-55℃的数值—将增量，指示温度高于-55℃。
同时，计数器用钭率累加器电路所决定的值进行予置。为了对遵循抛物线规
律的振荡器温度特性进行补偿，这种电路是必需的。时钟再次使计数器计值至它达到零。如果门开通时间仍未结束，那么此过程再次重复。
钭率累加器用于补偿振荡器温度特性的非线性，以产生高分辩率的温度测量。通过改变温度每升高一度，计数器必须经历的计数个数来实行补偿。因此，为了获得所需的分辩率，计数器的数值以及在给定温度处每一摄氏度的计数个数（钭率累加器的值）二者都必须知道。
此计算在DS1820 内部完成以提供0.5℃的分辩率。温度读数以16位、符号扩展的二进制补码读数形式提供表1 说明输出数据对测量温度的关系。数据在单线接口上串行发送。DS1820 可以以0.5℃ 的增量值，在0.5℃至+125℃的范围内测量温度。对于应用华氏温度的场合必须使用查找表或变换系数。
注意在DS1820 中温度是以1/2 LSB 最低有效位形式表示时产生以下9 位格式：
最高有效（符号）位被复制到存储器内两字节的温度寄存器中较高MSB 的所有位，这种“符号扩展”产生了如表1 所示的16 位温度读数。
以下的过程可以获得较高的分辩率。首先，读温度，并从读得的值截去0.5℃位(最低有效位)。这个值便是TEMP_READ。然后可以读留在计数器内的值。此值是门开通期停止之后计数剩余（COUNT_REMAIN）。
所需的最后一个数值是在该温度处每一摄氏度的计数个数（COUNT_PER_C）。于是，用户可以使用下式计算实际温度：
硬件接法
根据定义，单线总线只有一根线：这一点是重要的，即线上的第一个器件能在适当的时间驱动该总线。为了做到这一点，第一个连接到单线总线上的器件必须具有漏极开路或三态输出。DS1820 的单线接口（I/O 引脚是漏极开路的，其内部等效电路如图9 所示）多站multidrop 总线由单线总线和多个与之相连的从属器件组成。单线总线要求近似等于5k的上拉电阻。
单线总线的空闲状态是高电平。不管任何原因，如果执行需要被挂起，那么，若要重新恢复执行，总线必须保持在空闲状态。如果不满足这一点且总线保持在低电平时间大于480us，那么总线上所有器件均被复位。
存在脉冲（presence pulse）使总线主机知道DS1820 在总线上并已准备好工作。详情见“单线信号”一节。
处理顺序
经过单线接口访问DS1820 的协议（protocol）如下：
·初始化
《plc电梯控制英文文献五千字翻译(适用于本科毕业设计》
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