电子类专业英语翻译考试专用

Digital signal processing (DSP) is concerned with the representation of the signals by a sequence of numbers or symbols and the processing of these signals. Digital signal processing and analog signal processing are subfields of signal processing. DSP includes subfields like audio and speech signal processing, sonar and radar signal processing, sensor array processing, spectral estimation, statistical signal processing, digital image processing, signal processing for communications, biomedical signal processing, seismic data processing, etc.数字信号处理（DSP）是关注的信号通过一组数字或符号序列，这些信号处理的代表性。数字信号处理和模拟信号处理是信号处理的子领域。 DSP的包括像子字段：音频和语音信号处理，声纳和雷达信号处理，传感器阵列处理，谱估计，统计信号处理，数字图像处理，通信信号处理，生物医学信号处理，地震数据处理。

Since the goal of DSP is usually to measure or filter continuous real-world analog signals, the first step is usually to convert the signal from an analog to a digital form, by using an analog to digital converter. Often, the required output signal is another analog output signal, which requires a digital to analog converter. Even if this process is more complex than analog processing and has a discrete value range, the stability of digital signal processing thanks to error detection and correction and being less vulnerable, to noise makes it advantageous over analog signal processing for many, though not all, applications.由于DSP的目标通常是对连续的真实世界的模拟信号进行测量或滤波，第一步通常是通过使用一个模拟到数字的转换器将信号从模拟信号转化到数字信号。通常，所需的输出信号却是一个模拟输出信号，因此这就需要一个数字到模拟的转换器。即使这个过程比模拟处理更复杂的和而且具有离散值，由于数字信号处理的错误检测和校正不易受噪声影响，它的稳定性使得它优于许多模拟信号处理的应用（虽然不是全部）Sampling is usually carried out in two stages, discretization and quantization. In the discretization stage, the space of signals is partitioned into equivalence classes and quantization is carried out by replace the signal with representative signal values are approximated by values from a finite set.采样通常分两阶段进行，离散化和量化。在离散化阶段，信号的空间被划分成等价类和量化是通过一组有限的具有代表性的信号值来代替信号近似值。

The Nyquist-Shannon sampling theorem states that a signal can be exactly reconstructed from its samples if the sampling frequency is greater than twice the highest frequency of the signal. In practice, the sampling frequency is often significantly more than twice the required bandwidth.奈奎斯特-香农采样定理指出，如果样本的取样频率大于两倍的信号的最高频率，一个信号可以准确地重建它的样本。在实践中，采样频率往往大大超过所需的带宽的两倍。

A digital to analog converter (DAC) is used to convert the digital signal back to analog signal. The use of a digital computer is a key ingredient in digital control systems.数字模拟转换器（DAC）用于将数字信号转化到模拟信号。数字计算机的使用是数字控制系统中的一个关键因素。

DSP algorithms have long been run on standard computers, on specialized processors called digital signal processors (DSPs), or on purpose-built hardware such as application-specific integrated circuit (ASICs). Today there are additional technologies used for digital signal processing including more powerful general purpose microprocessors, field-programmable gate arrays (FPGAs), digital signal controllers (mostly for industrial applications such as motor control), and stream processors, among others.DSP算法一直是运行在标准的计算机，被称为数字信号处理器（DSP）

的专用处理器或在专用硬件如特殊应用集成电路（ASIC）。

目前有用于数字信号处理的附加技术包括更强大的通用

微处理器，现场可编程门阵列（FPGA），数字信号控制器

（大多为工业应用，如电机控制）和流处理器和其他相关

技术。

In DSP, engineers usually study digital signals in one of

the following domains: time domain (one-dimensional

signals), spatial domain (multidimensional signals),

frequency domain, autocorrelation domain, and wavelet

domains. They choose the domain in which to process a

signal by making an informed guess (or by trying different

possibilities) as to which domain best represents the essential

characteristics of the signal. 在数字信号处理过程中，工程

师通常研究数字信号的以下领域：时间域（一维信号），

空间域（多维信号），频率域，域和小波域的自相关。他

们选择在哪个领域过程中的一个信号，做一个明智的猜测

（或通过尝试不同的可能性）作为该域的最佳代表的信号

的本质特征。

A sequence of samples from a measuring device

produces a time or spatial domain representation, whereas a

discrete Fourier transform produces the frequency domain

information that is the frequency spectrum. Autocorrelation is

defined as the cross-correlation of the signal with itself over

varying intervals of time or space.从测量装置对样品序列产

生一个时间或空间域表示，而离散傅立叶变换产生的频谱

的频率域信息。自相关的定义是互相关的信号本身在不同

时间间隔的时间或空间的相关情况。

DSP technology is nowadays commonplace in such

devices as mobile phones, multimedia computers, video

recorders, CD players, hard disc drive controllers and

modems, and will soon replace analog circuitry in TV sets

and telephones.DSP技术是当今普遍在手机，多媒体计算

机，录像机，CD播放器，硬盘驱动器和控制器的调制解

调器等设备，并将很快在电视和电话业务中取代模拟电

路。

The main applications of DSP are audio signal

processing, audio compression, digital image processing,

video compression, speech processing, speech recognition,

digital communications, ranar, sonar, seismology, and

biomedicine. DSP主要应用的音频信号处理，音频压缩，

数字图像处理，视频压缩，语音处理，语音识别，数字通

信，雷达，声纳，地震，和生物医学。

An important application of DSP is in signal

compression and decompression. Signal compression is used

in digital cellular phones to allow a greater number of calls to

be handled simultaneously within e ach local “cell”. DSP

signal compression technology allows people not only to talk

to one another but also to see one anther on their computer

screens, using small video cameras mounted on the computer

monitors, with only a conventional telephone line linking

them together. DSP的一个重要的应用是信号的压缩和解

压。信号压缩用于数字蜂窝电话，在每一个地方的“单元”

让更多的电话同时被处理。DSP信号压缩技术不仅使人们

可以相互交谈，而且可以通过使用安装在计算机上的小的

摄像机使人们通过显示器看见对方，而这些只需要将传统

的电话线连接在一起。

The development of digital signal processing dates from

the 1960’s with the use of mainframe digital computers

number-crunching applications such an the Fast Fourier

Transform (FFT), which allows the frequency spectrum of a

signal to be computed rapidly. These techniques are not

widely used at that time, because suitable computing

equipment was generally available only in universities and

other scientific research institutions.数字信号处理的发展从

1960年代的大型数字计算机的数字运算应用程序的使用

快速傅立叶变换（FFT），它允许一个信号的频谱可以快速

计算。这些技术在当时没有被广泛使用，因为合适的计算

设备通常仅在大学及其他科研机构可以使用。

In brief, DSPs are processors or microcomputers whose

hardware, software, and instruction sets are optimized for

high-speed numeric processing applications- an essential

for processing digital data representing analog signals in real

time.总之，DSP处理器后者是微机的硬件、软件和指令集

的优化高速数字处理必不可少的，模拟信号处理数字数据

代表在真正的时间。

General-purpose microprocessors such as the Inter x86

family are not ideally suited to the numerically-intensive

requirements of DSP, and during the 1980’s the increasing

importance of DSP led several major electronics

manufacturers (such as Texas Instruments, Analog Devices

and Motorola) to develop Digital Signal Processor

chips-specialised microprocessors with architectures designed

specifically for the types of operations required in digital

signal processing. 通用微处理器如Intel x86的家庭并不适

合于DSP的计算密集型的需求，随着20世纪80年代DSP

重要性的增加导致几个主要的电子产品制造商（如德克萨

斯仪器，模拟设备和摩托罗拉）去开发数字信号处理器芯

片，专门的微处理器，专门设计用于在数字信号处理要求

的操作的类型的架构。

Like a general-purpose microprocessor, a DSP is a

programmable device, with its own native instruction code.

DSP chip are capable of carrying out millions of floating

point operations per second, and like their better-known

general-purpose cousins, faster and more powerful versions

are continually being introduced. DSPs can also be embedded

within complex “system-on-chip” devices, often containing

both analog and digital circuitry. 像一个通用微处理器，DSP

是一种具有其自己的本地指令代码的可编程器件。DSP芯

片是能够每秒进行数以百万计的浮点运算，像他们同类型

的更著名的通用器件，更快和更强大的版本正在不断被引

入。DSP也可以嵌入在复杂的“系统芯片”装置，通常包

括模拟和数字电路。

Using DSP, one can more easily design, modify, and

depend on filters using a DSP ,because the filter function on

the DSP is software-based, flexible, and repeatable. Further,

to create flexibly adjustable filters with higher-order response

requires only software modifications, with no additional

hardware- unlike purely analog circuits. 利用DSP，可以更

容易地设计，修改，和依赖于使用DSP滤波器，因为在

DSP滤波器的功能是基于软件的，灵活的，可重复的。此

外，创建具有高阶响应的灵活可调滤波器只需要修改软

件，不需要额外的硬件-不像纯模拟电路。

When acting as a digital filter, for example, the DSP

receives digital values based on samples of a signal,

calculates the results of a filter function operating on these

values, and provides digital values that represent the filter

output; it can also provide system control signals based on

properties of these values. The DSP’s high-speed arithmetic

and logical hardware is programmed to rapidly execute

algorithms modelling the filter transformation.当作为数

字, 例如,DSP接收数字值基于样本的一个信号,计算结果

一个过滤器的功能操作这些值,并提供数字值,代表了过滤

器的输出, 它还可以提供系统控制信号基于这些值的属

性, DSP的高速算术和逻辑的硬件被编程来迅速执行算法

建模过滤器转换。