通信英语(第四版)课后习题名词解释答案加翻译句子

通信英语

1.PCM原理

抽样量化与编码:sampling,quantizing and coding

话路:speech channel

幅值: amplitude value

抽样频率: sampling frequency

抽样速率: sampling rate

脉冲流: stream of pulses

重复率: repetition rate

编码过程: coding process

模拟信号: analog signal

传输质量: transmission quality

数字通信: digital communication

数字传输: digital transmission

含噪声的环境: noisy environment

传输路由: transmission path

信噪比 :signal-to-noise ratio

信号电平 :signal levels噪声功率: noise power

地面系统: terrestrial system

二进制传输: binary transmission

反向操作: reverse operation

8-位码序列: 8-digit sequence

接受端: receiving terminal

帧格式 :frame format

同步字 :synchronization word

实现这三项功能的方案 :the schemes for performing these three functions

一串幅值: a series of amplitude values

电话质量的话路 a speech channel of telephone quality

一个8位二进制码的序列: a sequence of 8-binary digits

理论上的最小抽样频率 :a minimum theoretical sampling frequency

占据着300Hz到3.4kHz频率范围的话路: a voice channel occupying the range 300Hz to 3.4kHz 每个样值8-位码: 8-digits per sample value

汽车点火系统的打火: the sparking of a car ignition system

重复率为64kHz的脉冲流: the stream of the pulses with a repetition rate of 64kHz

真实信号与噪声信号的关系: relationship of the true signal to the noise signal

由卫星上接受到的信号 :the signal received from a satellite

一条特定消息中的全部信息 :the complete informatian about a particular message

被传信号的波形 :the shape of the transmitted signal

由传输路由引入的衰减: the attenuation introduced by transmission path

将抽样的幅值转换成一串脉冲的单元 :the unit that converts sampled amplitude value to a set of pulses

涉及到第一路，第二路及其他各路的序列: a sequence relating to channel 1,2 and so on 被称为同步字的独特码序列: a unique sequence of pulses called synchronization word

地面系统 :terrestrial system

脉冲的“有”或“无” : the presence or absence of the pulses

通信英语

高速的电子开关: a high-speed electronic switch

时分多路复用器 :the time pision multiplexer

时分多路复用 :Time Division Multiplexer

2.异步串行数据传输

串行接口 serial interface

显示终端 CRT terminal

发送器与接收器 transmitter and receiver

数据传输 data transmission

数据流 data stream

闲置状态 the idle state

传号电平 mark level

空号电位 space level

起始位 start bit

停止位 stop bit

T秒的持续时间 duration of T seconds

奇偶校检位 parity bit

错误标志 error flag

传输错误 transmission error

下降沿 fallinf edge

符号间的空格 intersymbol space

接收机的定时 receiver timing

本地时钟 local clock

磁带 magnetic tape

控制比特 control bit

逻辑1电平 logical 1 level

二进制数据 binary data

明显的缺点 obvious disadvantage

异步串行数据传输 asynchronous serial data transmission

最为流行的串行接口 the most popular serial interface

所传送的数据 the transmitted data

发送器与接收器的时钟 the clocks at the transmitter and receiver

电传机的时代 the era of teleprinter

一个字符的点和划 the dots and dashs of a character

符号间空格持续时间的三倍 three times the duration of intersymbol space

被称为字符的比特组 the group of bits called characters

由7或8个比特的信息组成的固定单元 the invariable units comprising 7 or 8 bits of information 由接收机本地产生的时钟 a clock generated locally by the receiver

在字符后所收到的奇偶校检位 the received parity bit following the character

起始位的下降沿 the falling edge of the start bit

数据链路面向字符的特性 the character-oriented nature of the data link

3.数据通信

地下电缆 underground cable

通信卫星 communication satellite

微波设备 microwave facilities

通信英语

调制器与解调器 modulator and demodulator

缓冲器 buffer

定时信号 timing signals

同步脉冲 synchronization pulses

时隙 time slot

移位寄存器 shift register

传输媒体 transmission medium

线形衰弱 linear attenuation

信息安全 information security

键盘 keyboard

数据终端 data terminals

某种类型的数据转换设备 some type of data conversion equipment

视频显示终端 visual display terminal

称为数据调制解调器的双向数据发送接收机 two-way data transmistter-receiver called a data modem 全双工的数据传输系统 full-duplex data trandmission system

由数据处理器的运算速率所决定的速率 the rate determined by the operating speed of the data processor

由接口部件来的定时信号 timing signals from the interface assembly

磁心存储器 magnetic core memories

线性衰减和时延特性 linear attenuation and delay characteristics

传输损伤 transmission impairments

语音中的冗余特性 the redundant nature of speech

在数据发送器中的编码过程 coding process in the data transmitter

二进制的不归零信号 binary nonreturn-to-zero signal

4.互联网

网络资源：network resource

信息服务：information services

远程终端：remote terminals

互联的系统：interconnected systems

命令：command

电子邮件：electronic mail

主机：host

无线信道：wireless channels

搜索工具：searching tools

用户界面：user interface

存取：access

文本信息：textual messages

协议：protocol

超文本协议：hypertext protocol

分布在全世界的计算机的巨大网络：gaint network of computers located all over the world 主干系统：backbone system

全国范围的网络：nationwild network

电子会议：electronic conferences

实时对话：live conversation

通信英语

最大的信息库the largest repository of the computers on the net

网络设备资源：network facilities resources