Digital system: entity can process, transfer and store any kind of digital signals is Composed of individual digital logic circuits which are designed to perform specified function

信号与系统（英文版）_3 Fourier Series Representation of Periodic Signals

3.1 Discrete-Time Fourier Transform Definition- The discrete-time Fourier transform (DTFT) X(eio) of a sequence x[n] is given by jae In general,() is a complex function of the real variable and can be written as X(eio) Xre(eio) +j Xim(eio)

信号与系统（英文版）_6. Time and Frequency Characterization of Signals and Systems

电子科技大学《数字信号处理》英文PPT课件：Chapter 5 Digital Processing of Continuous-Time- Signals

电子科技大学《数字信号处理》英文PPT课件：Chapter 2 Discrete-Time Signals and Systems

电子科技大学《数字信号处理》英文PPT课件：Chapter 1 Continuous--time Signals and Systems