Let be a band-limited signal with then is uniquely determined by its samples if where

6.1 The Magnitude-Phase Representation （ 幅度-相位） of the Fourier Transform

4.1 Representation of Aperiodic Signals :The Continuous-Time Fourier Transform

1. Continuous-time system 2. Discrete-time system

2.1 Discrete-time LTI Systems : The Convolution Sum （卷积和） 2.1.1 The Representation of Discrete-Time Signals in Terms of impulses

1. is absolutely summable, 2. has finite energy

Chapter 1 Signals and Systems (1) A simple RC circuit Source voltage Vs and Capacitor voltage Vc (2) An automobile

6.23 Shown in Figure 6.23 is for a lowpass filter. Determine and sketch the impulse response of the filter for each of the following phase characteristics:

4.3 4.4 4.10 4.11 4.14 4.15 4.24 4.25 4.32 4.35 4.36 4.37 4.43

3.1 3.13 3.15 3.34 3.35