apter 2 Discrete-Time signals and systems ◆2.0 Introduction 2. 1 Discrete-Time Signals: Sequences 2.2 Discrete-Time Systems 2.3 Linear Time-Invariant (LTI) Systems 2.4 Properties of LTI Systems 2,5 Linear Constant- Coefficient Difference equations 2/2/2021 Zhongguo Liu_ Biomedical Engineering_shandong Univ
2 2/2/2021 Zhongguo Liu_Biomedical Engineering_Shandong Univ. Chapter 2 Discrete-Time Signals and Systems ◆2.0 Introduction ◆2.1 Discrete-Time Signals: Sequences ◆2.2 Discrete-Time Systems ◆2.3 Linear Time-Invariant (LTI) Systems ◆2.4 Properties of LTI Systems ◆2.5 Linear Constant-Coefficient Difference Equations
apter 2 Discrete-Time signals and systems 92. 6 Frequency- Domain Representation of Discrete-Time Signals and systems 2.7 Representation of Sequences by Fourier transforms 2. 8 Symmetry Properties of the Fourier transform 2.9 Fourier Transform Theorems 2. 10 Discrete- Time Random signals ◆211 Summary 2/2/2021 Zhongguo Liu_ Biomedical Engineering_shandong Univ
3 2/2/2021 Zhongguo Liu_Biomedical Engineering_Shandong Univ. Chapter 2 Discrete-Time Signals and Systems ◆2.6 Frequency-Domain Representation of Discrete-Time Signals and systems ◆2.7 Representation of Sequences by Fourier Transforms ◆2.8 Symmetry Properties of the Fourier Transform ◆2.9 Fourier Transform Theorems ◆2.10 Discrete-Time Random Signals ◆2.11 Summary
2.0 Introduction Signal: something conveys information Signals are represented mathematically as functions of one or more independent variables Continuous-time(analog) signals, discrete time signals digital signals Signal-processing systems are classified along the same lines as signals: Continuous-time(analog) systems discrete-time systems digital systems ◆ Discrete-time signal Sampling a continuous-time signal o Generated directly by some discrete-time process 2/2/2021 Zhongguo Liu_ Biomedical Engineering_shandong Univ
4 2/2/2021 Zhongguo Liu_Biomedical Engineering_Shandong Univ. 2.0 Introduction ◆Signal: something conveys information ◆Signals are represented mathematically as functions of one or more independent variables. ◆Continuous-time (analog) signals, discretetime signals, digital signals ◆Signal-processing systems are classified along the same lines as signals: Continuous-time (analog) systems, discrete-time systems, digital systems ◆Discrete-time signal ◆Sampling a continuous-time signal ◆Generated directly by some discrete-time process
2.1 Discrete-Time Signals: Sequences Discrete-Time signals are represented as ins 00<n<∞,n: Integer Cumbersome, so just use xIn ◆ In sampling, xn =xo(nr), T: sampling period ◆1/T(〔 reciprocal of T): sampling frequency 5 2/2/2021 Zhongguo Liu_ Biomedical Engineering_shandong Univ
5 2/2/2021 Zhongguo Liu_Biomedical Engineering_Shandong Univ. 2.1 Discrete-Time Signals: Sequences ◆Discrete-Time signals are represented as ◆In sampling, ◆1/T (reciprocal of T) : sampling frequency x =xn, − n , n:integer xn= xa (nT), T :sampling period Cumbersome, so just use x n
Figure 2.1 Graphical representation of a discrete-time signa -2 2 7891011 94-7-6-54-3-2-10123456 Abscissa: continuous line x[n: is defined only at discrete instants 6 2/2/2021 Zhongguo Liu_ Biomedical Engineering_Shandong Univ
6 2/2/2021 Zhongguo Liu_Biomedical Engineering_Shandong Univ. Figure 2.1 Graphical representation of a discrete-time signal Abscissa: continuous line x n : is defined only at discrete instants