专业英语Lesson 2 Aperiodic Signal.ppt

《电子信息工程专业英语教程》 Lesson 2 Aperiodic Signal Backgrounds Text tour Language in use Vocabulary Structure Reading/writing techniques Backgrounds Terminology Fourier series 傅立叶级数 The real part 实部 The imaginary part 虚部 Amplitude 振幅 Spectrum 频谱 The unit step function 单位阶越函数 The exponentially decaying 指数衰减阶跃函数 Lasplace transform 拉普拉斯变换 Pole 极点 Zero 零点 Argand diagram 阿根图 　 Text tour Outline 2.1 Introduction 2.2 The Exponential Form of the Fourier Series 2.3 The Fourier Transform 2.4 The Laplace Transform 2.1 Introduction The introduction of Aperiodic signal 2.2 The Exponential Form of the  Fourier Series The Exponential Form of the Fourier Series = analysis 2.3 The Fourier Transform 2.3.1 Derivation 2.3.2 Examples of Continuous Spectra 2.3.3 Symmetry of the Fourier Integral Equations 2.3.4 Limitations of the Fourier Transform 2.3.1 Derivation the exponential form of the Fourier series (ⅰ) = (ⅱ) = 2.3.1 Derivation the exponential form of the Fourier series function 2.3.2 Examples of Continuous Spectra the spectrum of the isolated pulse waveform Figure 2.1 (a) A Signal isolated Pulse and (b) its Frequency Spectrum 2.3.2 Examples of Continuous Spectra The spectrum of this pulse waveform illustrates a number of important points about time-limited signals. Figure 2.2 (a) Two isolated pulse, one of long and the other of short duration, and (b) their corresponding spectra. Only a small part of the () spectrum of the short pulse is shown 2.3.2 Examples of Continuous Spectra evaluate the spectrum of the exponentially decaying sinusoidal waveform = 2.3.2 Examples of Continuous Spectr