发信人: ljlinjie (水狗->图象识别), 信区: CRC
标 题: 通信英语--通信系统:几点翻译
发信站: 哈工大紫丁香 (2002年10月14日21:04:09 星期一), 站内信件
1 通信系统的功能
——通信系统的功能是从一个地点准确地传送信息到另一个地点。在过去,通信系
统的终点是人,但现在由于自动数据处理系统及自动控制系统的出现,终点是机器
的情况已不罕见。通信系统有效性的度量是它传递信息的效率,由下列参数描述:
—a. 准确度。用话音质量(在数据系统中则用差错率)来度量。
—b. 所传递信息的数量。
—c. 传递信息的速度。
——这些参数都是可度量的,并被规范为一个系统的基本设计准则。系统的最终形
式要取决于对每一个参数的侧重程度。
Function of a communication system
The function of a communication system is to pass information accurately
from one place to another. In the past the terminal points of a
communication system were human beings but it is now not uncommon,
with the advent of ADP and automatic control system, for the terminals
to be machines. The measure of the effectiveness of a communication
system is its efficiency in passing information and this is described by
the following parameters:
a. Accuracy. This is measured in term of speech quality or error rate in
data systems.
b. Quantity of information passed.
c. Speed of passing information.
These parameters are measurable and are specified as the basic design
criteria of a system, and the final form of the system depends on the
emphasis on each.
2 通信系统
——一般化的通信系统由下列组成部分:
——a. 信息源。它产生消息,可以是写成的或口说的文字,或是某种形式的数据
。
——b. 发信机。发信机把消息转变为信号,信号形式要适合在通信信道种传送。
——c. 通信信道。通信信道是用于从发信机传送信号到接收机的媒质。信道可以
是无线电链路或者是直接的有线连接。
——d. 接收机。接收机可以看作与发信机相反的东西。它把接收到的信号变回成
消息,并把消息传给信息宿,这个信宿可以是一台扬声器、电传打字机、或一个计
算机数据库。
所有通信信道的一个不幸的特征是信号上都迭加了噪声。这种人们不希望存在的噪
声会引起电话中声音失真,或者在电报报文或数据中的差错。
Communication System
A generalized communication system has the following components:
a. Information Source. This produces a message which may be written or
spoken words, or some form of data.
b. Transmitter. The transmitter converts the message into a signal,
the form of which is suitable for transmission over the communication
channel.
c. Communication Channel .The communication channel is the medium used
transmit the signal, from the transmitter to the receiver .The channel
may be a radio link or a direct wire connection.
d. Receiver. The receiver can be thought of as the inverse of the
transmitter. It changes the received signal back into a message and
passes the message on to its destination which may be a loudspeaker,
teleprinter or computer data bank.
An unfortunate characteristic of all communication channels is that
noise is added to the signal. This unwanted noise may cause
distortions of sound in a telephone, or errors in a telegraph message or
data.
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