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Linear system. Lesson 3. Signals and systems. Linear system. (1) Unit step function. Shift a. Linear system. Area=1. Amplitude. width. (2) Unit impulse function. Linear system. (3) Unit doublet function. Linear system. …. Sampling. Linear system. (4) sign function.
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Linear system Lesson 3 Signals and systems
Linear system (1) Unit step function Shift a Meiling CHEN
Linear system Area=1 Amplitude width (2) Unit impulse function Meiling CHEN
Linear system (3) Unit doublet function Meiling CHEN
Linear system … Sampling Meiling CHEN
Linear system (4) sign function (5) Unit ramp signal Meiling CHEN
Linear system (6) parabolic signal (7) sinc signal Meiling CHEN
Linear system Signal Classification • Periodic and aperiodic • Even and odd • Real and complex • Continuous-time and discrete-time • Deterministic and stochastic (random) • Causal and noncausal Meiling CHEN
Linear system Periodic signals Even signals odd signals Meiling CHEN
Linear system Causal signals Anticausal signals Meiling CHEN
Linear system Causal and noncausal system Example: distinguish between causal and noncausal systems in the following: (1) Case I Noncausal system Meiling CHEN
Linear system (2) Case II Delay system causal system (3) Case III causal system At present past Meiling CHEN
Linear system (4) Case IV noncausal system At present future (5) Case V noncausal system Meiling CHEN
Linear system Signal operations • Simple operation : +、- • Convolution : * Meiling CHEN
Linear system simple operation Meiling CHEN
Linear system Convolution Integral : Linear system Linear system … Meiling CHEN
Linear system Linear system I.C.=0 Impulse response Transfer function of the system Linear system I.C.=0 Any input Zero state response Meiling CHEN
Linear system Example : Graphical convolution (1) Meiling CHEN
Linear system (2) (3) Meiling CHEN
Linear system (4) (5) Meiling CHEN
Linear system Ans: Meiling CHEN
Linear system Laplace and convolution integral Algebra operator Meiling CHEN
Linear system Example Meiling CHEN
Linear system Hint: Meiling CHEN
Laplace transform For causal signals pass through linear time-invariant causal systems Complex frequency Meiling CHEN
Linear system Laplace transform properties Meiling CHEN