viii CONTENTSFrequency and Time Scaling Number of Samples Complex Frequency-Domain Sequences xn Versus Time and Xk Versus Frequency One-Sided Sequences Combinations of Two-Sided Phasors
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Frequency and Time Scaling
Number of Samples
Complex Frequency-Domain Sequences
x(n) Versus Time and X(k) Versus Frequency
One-Sided Sequences
Combinations of Two-Sided Phasors
Time and Spectrum Transformations
Transforming Two-Sided Phasor Sequences into
One-Sided Sine, Cosine, θ
Example 2-1: Nonlinear AmpliÞer Distortion
and Square Law Modulator
Example 2-2: Analysis of the Ramp Function
Spectral Leakage Noninteger Values of Time x(n) and
Frequency X(k)
Example 3-1: Frequency Scaling to Reduce Leakage
Aliasing in the Frequency Domain
Example 3-2: Analysis of Frequency-Domain Aliasing
Aliasing in the Time Domain
Smoothing the Rectangular Window, Without Noise
and with Noise
Smoothed Sequences Near the Beginning and End
Rectangular Window
Hamming Window
Hanning (Hann) Window
Relative Merits of the Three Windows
Scaling the Windows
Sequence Multiplication
Polynomial Multiplication
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Convolution
Discrete Convolution Basic Equation
Relating Convolution to Polynomial Multiplication
“Fold and Slide” Concept
Circular Discrete Convolution (Try to Avoid)
Sequence Time and Phase Shift
DFT and IDFT of Discrete Convolution
Fig 5-6 Compare Convolution and Multiplication
Deconvolution
Properties of a Discrete Sequence
Expected Value of x(n)
Include Some Additive Noise
Envelope Detection of Noisy Sequence
Average Power of Noiseless Sequence
Power of Noisy Sequence
Sequence Averaging
Variance
Gaussian (Normal) Distribution
Cumulative Distribution
Correlation and Covariance
Autocorrelation
Cross-Correlation
Autocovariance
Cross-Covariance
Correlation CoefÞcient
Finding the Power Spectrum
Two-Sided Phasor Spectrum, One-Sided Power Spectrum
Example 7-1: The Use of Eq (7-2)
Random Gaussian Noise Spectrum
Measuring the Power Spectrum
Spectrum Analyzer Example
Wiener-Khintchine Theorem
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System Power Transfer
Cross Power Spectrum
Example of Calculating Phase Noise
The Perfect Hilbert Transformer
Example of a Hilbert Transform of an Almost-Square Wave
Smoothing of the Example
Peaks in Hilbert of Square Wave
Mathematics of the Hilbert Transform
Analytic Signal
Example 8-2: Construction of Analytic Signal
Single-Sideband RF Signals
SSB Design
Basic All-Pass Network
−90◦ Cascaded Phase Shift Audio Network
Why the−90◦ Network Is Not Equivalent to a Hilbert
Transformer
Phasing Method SSB Transmitter
Filter Method SSB Transmitter
Phasing Method SSB Receiver
Filter Method SSB Receiver
Appendix: Additional Discrete-Signal Analysis and Design
Discrete Derivative
State-Variable Solutions
Using the Discrete Derivative to Solve a Time Domain
Discrete Differential Equation
Trang 4The Introduction explains the scope and motivation for the title subject
My association with the Engineering Department of Collins Radio Co., later Rockwell Collins, in Cedar Rapids, Iowa, and my education at the University of Iowa have been helpful background for the topics covered The CD accompanying the book includes the Mathcad V.14 Aca-demic Edition, which is reproduced by permission This software is fully functional, with no time limitation for its use, but cannot be upgraded For technical support, more information about purchasing Mathcad, or upgrading from previous editions, see http://www.ptc.com
Mathcad is a registered trademark of Parametric Technology Corpora-tion (PTC), http://www.ptc.com PTC owns both the Mathcad software program and its documentation Both the program and documentation are copyrighted with all rights reserved No part of the program or its docu-mentation may be produced, transmitted, transcribed, stored in a retrieval system, or translated into any language in any form without the written permission of PTC
William E Sabin
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