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6 Time and Frequency Characterization of Signals and Systems 6.0 Introduction Meanings of the Fourier Transform of a CT signal Magnitude-Spectrum and Phase-Spectrum ( The magnitude and phase angle of the CTFT ) Meanings of the Frequency response of a LTI system
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6 Time and Frequency Characterization of Signals and Systems 6.0 Introduction Meanings of the Fourier Transform of a CT signal Magnitude-Spectrum and Phase-Spectrum ( The magnitude and phase angle of the CTFT ) Meanings of the Frequency response of a LTI system The magnitude and phase shift of the frequency response (The magnitude-frequency and phase-frequency characteristics) The distortionless transmission-system The Time and Frequency-domain properties of Frequency-Selective Filters Time and Frequency-domain properties of First and Second-Order systems
6.1 The Magnitude-Phase Representation of The Fourier Transform
Magnitude-Spectrum/ The magnitude of the CTFT : The complex magnitude of the frequency component is: The relative complex magnitude is
Phase-Spectrum/ The phase angle of the CTFT : The complex magnitude of the frequency component is: The relative complex magnitude is
clear all; t=-4:0.05:4; xt=cos(0.56*pi*t)+cos(0.28*pi*t)+cos(t); plot(t,xt,'b'); xlabel('t'); hold on y1t=cos(0.56*pi*t-pi/3)+cos(0.28*pi*t-2*pi/3)+cos(t-pi/2); plot(t,y1t,'r'); y2t=cos(0.56*pi*(t-0.5*pi/2))+cos(0.28*pi*(t-0.5*pi/2))+cos(t-0.5*pi/2); plot(t,y2t,'c');title('x(t),y1(t),y2(t)');hold off
clear all; t=-4:0.05:4; xt=cos(0.56*pi*t)+cos(0.28*pi*t)+cos(t); plot(t,xt,'b'); xlabel('t'); hold on y1t=0.25*cos(0.56*pi*t)+0.5*cos(0.28*pi*t)+cos(t); plot(t,y1t,'r') y2t=cos(0.56*pi*t)+0.5*cos(0.28*pi*t)+0.25*cos(t); plot(t,y2t,'c');title('x(t),y1(t),y2(t)'); hold off
6.2 The Magnitude-Phase Representation of The Frequency Response of LTI Systems
The magnitude of the frequency response / The magnitude-frequency characteristic: The effect an LTI system has on the magnitude of the FT of a input signal is to scale it by the magnitude of the frequency response
The phase shift of the frequency response / The phase -frequency characteristic:
6.2.1 The distortionless transmission-system the distortionless transmission-system the distortionless transmission-system distortion
6.2.1 The distortionless transmission-system the distortionless transmission-system
clear all; t=-4:0.05:4; xt=cos(0.56*pi*t)+cos(0.28*pi*t)+cos(t); plot(t,xt,'b'); xlabel('t'); hold on y1t=cos(0.56*pi*t-pi/3)+cos(0.28*pi*t-2*pi/3)+cos(t-pi/2); plot(t,y1t,'r'); y2t=cos(0.56*pi*(t-0.5*pi/2))+cos(0.28*pi*(t-0.5*pi/2))+cos(t-0.5*pi/2); plot(t,y2t,'c');title('x(t),y1(t),y2(t)');hold off
clear all; t=-4:0.05:4; xt=cos(0.56*pi*t)+cos(0.28*pi*t)+cos(t); plot(t,xt,'b'); xlabel('t'); hold on y1t=0.25*cos(0.56*pi*t)+0.5*cos(0.28*pi*t)+cos(t); plot(t,y1t,'r') y2t=cos(0.56*pi*t)+0.5*cos(0.28*pi*t)+0.25*cos(t); plot(t,y2t,'c');title('x(t),y1(t),y2(t)'); hold off
SAS实验三线性失真的计算机仿真与分析 内容 1 无失真传输系统的概念,应满足的条件; 2 幅度失真的涵义,仿真分析; 3 相位失真的涵义,仿真分析; 4 幅度、相位失真的仿真分析; 5 总结 要求 1 理论分析完整、严谨; 2 仿真条件表述清晰,仿真结果具有说服力; 3 以学术论文格式写作。 文档类型:Word或PPT文档 文件名:学号_姓名_实验3