Signals and Systems - Electrical Engineering

(avery) #1
Index 751

moving average (MA), 481–482
nonlinear system, 498
time-invariance, 498
discrete-time Fourier transform
(DTFT), 572–596
convergence, 591
convolution sum, 595–596
downsampling and
upsampling, 582
eigenfunctions, 573–575
Parseval’s theorem, 585–587
sampled signal, 578–580
symmetry, 589–595
time and frequency shifts, 628
time-frequency duality, 628
time-frequency supports,
580–585
Z-transform, 573–575
discrete-time signals
absolutely summable, 575,
576, 628
basic, 465–478
definition, 452
Fibonacci sequence, 453
finite energy, 458–461
finite power, 458–461
inherently discrete-time, 452
sample index, 452
sinusoid, 469–472
square summable, 458
discrete transfer function, 655


E
energy, 80
discrete-time signals, 458–461
Euler’s identity, 23–24, 87
even signal, 279, 461–465


F
Fibonacci sequence
difference equation, 453
field-programmable gate array
(FPGA), 5
filtering, 276–278, 327–344
analog, 390–408
median filter, 495
filters
anti-aliasing, 430
passband, 332
RC high-pass filter, 336
RC low-pass filter, 277
finite calculus, 9
finite difference, 12–13
summations, 13–16


FIR filters and convolution sum,
528, 529, 531, 533
Fourier basis, 247
four-level quantizer, 441, 442
frequency, harmonically related, 83
frequency aliasing, 424
frequency modulation (FM), 87
frequency response, poles and zeros,
342, 343

G
Gibb’s phenomenon, 266, 267
filtering, 334
graphical convolution sum, 530

H
hybrid system, 119

I
ideal filters
band-pass, 332
high-pass, 332
linear phase, 332
low-pass, 332
zero-phase, 333
ideal impulse sampling, 421–428
inverse Laplace
with exponentials, 209
partial fraction expansion, 198
two-sided, 212–214
inverse Z-transform, 542–563
inspection, 542
long-division method, 542–543
partial fraction expansion,
544–546
positive powers of z, 545, 546

L
Laplace transform
convolution integral, 196–197
derivative, 189
integration, 193–194
inverse, 169, 197–214
linearity, 185–188
one-sided, 176–197
proper rational, 198
region of convergence (ROC),
166, 172–176
transfer function, 214, 223
two-sided, 166–176
length of convolution sum, 721
L’Hopital’s rule, 101, 306, 433
LTI systems, superposition, 135–136

M
magnitude line spectrum, 249
Matlab
analog Butterworth and
Chebyshev filter design, 414
analog Butterworth filtering, 414
control toolbox, 375
decimation and interpolation,
585
DFT and FFT, 577
discrete filter design, 644
DTFT computation, 577
FFT computation, 717
filter design, 405–408
Fourier series computation,
603–604
functions, 36
general discrete filter design, 646
numerical computations, 30
phase computation, 591
phase unwrapping, 592
plotting, 39–41
saving and loading, 41–43
symbolic computations, 43–53
vectorial operations, 33–35
vectors and matrices, 30–33

N
negative frequencies, 323
nonlinear filtering, median
filter, 495
nonzero initial conditions, 552
normality, 247
Nyquist sampling rate, 431
Nyquist sampling theorem, 431

O
odd signal, 75–77
one-sided Z-transform, 511
orthogonality, 248

P
Parseval’s relation and sampling,
427
periodic convolution, 609–614, 624
periodic discrete sinusoids, 454, 456
phase line spectrum, 249, 250, 253,
257, 259, 261, 263, 265
phase modulation (PM), 87, 378,
386
phasors, sinusoidal steady state,
24–26, 28
poles and zeros, 172–176
poles and zeros of Z-transforms, 511,
549, 551, 564
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