电子信息与通信工程专业英语期末必考翻译

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1."In most cases, these signals originate as sensory data from the real world: seismic vibrations visual images, sound waves, etc. DSP isthe mathematics, the algorithms, and the techniques used to manipulate these signals after they have been converted into a digital form." 在大多数情况下，这些信号来源于人对真实世界的感觉，比如地震的震动，视觉图像，声音波形等。数字信号处理是一种数学工具，是一种用来处理那些将上述信号转换成数字形式后的信号的算法和技术。

2.Fourier ’s representation of functionsas a superposition of sines and cosines has become Ubiquitous for both the analytic and numerical solution of differential equations and for the analysis and treatment of communication signals 函数的傅里叶表示，即将函数表示成正弦和余弦信号的叠加，这种方法已经广泛用于微分方程的解析法和数值法求解过程以及通信信号的分析和处理。

3.If f (t ) is a nonperiodic signal, the summation of the periodic functions ,such as sine and cosine, does not accurately represent the signal. You could artificially

extend the signal to make it periodic but it would require additional continuity at the end points . 如果f(t)是非周期信号，那么用周期函数例如正弦和余弦的和，并不能精确的表示该信号f(t)。你可以人为的拓展这个信号使其具有周期性，但是这要求在端点处附加连续性

4.A digital filter is a mathematical algorithm implemented in hardware, firmware, and software that operates on a digital input signal to produce a digital output signal for achieving filtering objectives. 数字滤波器是一种数学算法，它可以用硬件，固件和软件来实现。它作用于数字输入信号产生数字输出信号从而达到滤波目标。

5.The basic idea of Fourier series method is to design an FIR filter that approximates the desired frequency response of filter by calculating its impulse response. "用傅里叶级数设计FIR 滤波器的基本的理念是计算出此滤波器的单位冲激响应来逼近所期望的滤波器的频率响应。 "

6."If the signal has sharp transitions, it is necessary to window the

input data, so that the sections converge to zero at the endpoints" 如果信号有急剧的过渡，就有必有对输入信号加窗，这样信号在端点处就会收敛于零。

7." The concepts of signals a nd systems arise in a wide variety of fields, and the id eas and techniques associated with these concepts play an i mportant role in such diverse

areas of science and technolog y as communication,

aeronautics and astronautics, circuit design, acoustics, seismology, biomedical enginee ring, energy generation

distribution systems, chemical process control, and speech processing. " 信号与系统的概念出现在广阔的范围内，在科学技术的不同领域，如通信、航空航天、电路设计、声学、地震学、生物学、生物医学工程、发电和输电系统、化学过程控制和语音处理中都离不开这个概念的思想与技术。它在科学技术中发挥了重要作用。

8." Without some restrictions, when the

characterization of a system r equires a complete input-out-pu t relationship, knowing the ou tput of a system to a certai n set of input doe not allow us to determine the output of the system to other sets of inputs." 当系统的特性描述要求完整的输入输出关系时，如果没有约束条件，即使知道了系统对某 些特定输入产生的输出时，我们也并不知道系统对其他输入产生的输出。

9.An example of a finite-energ y signal is a signal that ta kes on the value 1 for 0≤t ≤1 and 0 otherwise. 举一个有限能量信号的例子：信号在0≤t ≤1，而在其他时间范围取值为0。

10.This, of course, makes sens e, since if there is a nonze ro average energy per unit ti me, then integrating or summin g this over an infinite time interval yields an infinite amount of energy. 当然这是有意义的，因为如果单位时间内存在一个非零的平均能量，那么在一个无限的时间间隔范围内，对其积分或者求和就会产生一个无限的能量总和。