Result: Linear phase e simply a rigid shift in time, no distortion Nonlinear phase e distortion as well as shift DT

1. DTFT Properties and Examples 2. Duality in fs& ft 3. Magnitude/Phase of Transforms and Frequency Responses

Portrait of Jean Baptiste Joseph Fourier Image removed due to copyright considerations Signals& Systems, 2nd ed. Upper Saddle River, N.J. Prentice Hall, 1997, p 179

1Some examples of systems 2 System properties and examples CAusality

Another(important! ) example: Periodic Impulse train n(t)=∑(t Sampling function important for sampling .2T

Convolution Property 0(t)=h(t)*(t)←→Y(j)=H(ju)X( where h(t)←→H(ju) A consequence of the eigenfunction property

Convergence Issues Synthesis equation: None. since integrating over a finite interval Analysis Equation: Need conditions analogous to CTFT, e. g

Representation of ct signals Approximate any input x(t) as a sum of shifted, scaled

《信号与系统》（第二版）第一章 习题解答

《信号与系统》（第二版）第二章 习题解答