Fundamentals of Signal Enhancement and
Array Signal Processing
Fundamentals of Signal Enhancement and
Array Signal Processing
Jacob Benesty
INRS, University of Quebec
Montreal, Canada
Israel Cohen
Technion, Israel Institute of Technology
Haifa, Israel
Jingdong Chen
Northwestern Polytechnical University
Xi’an, China
This edition first published
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v
Contents
xi
Preface
About the Companion Website
xiii
1
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Introduction
Signal Enhancement
Speech Enhancement and Noise Reduction
Underwater Acoustic Signal Enhancement
Signal Enhancement in Radar Systems
Signal Enhancement in Ultrasound Systems
Approaches to Signal Enhancement
Array Signal Processing
Organization of the Book
How to Use the Book
References
Part I Signal Enhancement
Single-channel Signal Enhancement in the Time Domain
Signal Model and Problem Formulation
Wiener Method
Linear Filtering
Performance Measures
2
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..
..
.. Optimal Filters
Spectral Method
.
Joint Diagonalization and Reformulation of the Problem
..
.. Noise Reduction with Gains
..
.. Determination of the Gains from the Fullmode Output SNR
Performance Measures
Problems
References
3
.
.
Single-Channel Signal Enhancement in the Frequency Domain
Signal Model and Problem Formulation
Noise Reduction with Gains
vi
Contents
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.
.
.
Performance Measures
Optimal Gains
Constraint Wiener Gains
Implementation with the Short-time Fourier Transform
Problems
References
Multichannel Signal Enhancement in the Time Domain
Signal Model and Problem Formulation
Conventional Method
Joint Diagonalization
Linear Filtering
Performance Measures
4
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..
..
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.. Optimal Filtering Matrices
.
..
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.. Optimal Filters
.
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.. Maximization of the Output SNR
.. Minimization of the Output SNR
Spectral Method
Temporal Joint Diagonalization and Reformulation of the Problem
Spatial Joint Diagonalization
Spatial Linear Filtering
Performance Measures
Case of a Rank Deficient Noise Correlation Matrix
Eigenvalue Decompositions
Problems
References
Multichannel Signal Enhancement in the Frequency Domain
Signal Model and Problem Formulation
Linear Filtering
Performance Measures
Input SNR
5
.
.
.
..
.. Output SNR
.. Noise Rejection and Desired Signal Cancellation
.. Desired Signal Distortion Index
.. MSE Criterion
.
Optimal Filters
.. Maximum SNR
.. Wiener
.. MVDR
.. Tradeoff
LCMV
..
.
Generalized Sidelobe Canceller Structure
A Signal Subspace Perspective
.
Joint Diagonalization
..
..
Estimation of the Desired Signal
Contents
vii
.
Implementation with the STFT
Problems
References
6
An Exhaustive Class of Linear Filters
.
Signal Model and Problem Formulation
.
Linear Filtering for Signal Enhancement
.
Performance Measures
.
Optimal Filters
.. Wiener
.. MVDR
.. Tradeoff
LCMV
..
.. Maximum SINR
.. Maximum SIR
.
Filling the Gap Between the Maximum SINR and Wiener Filters
Problems
References
Part II Array Signal Processing
Fixed Beamforming
Signal Model and Problem Formulation
Linear Array Model
Performance Measures
Spatial Aliasing
Fixed Beamformers
7
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.. Delay and Sum
.. Maximum DF
..
Superdirective
..
Robust Superdirective
.. Null Steering
.
..
.. Compromising Between WNG and DF
A Signal Subspace Perspective
Joint Diagonalization
Problems
References
Adaptive Beamforming
Signal Model, Problem Formulation, and Array Model
Performance Measures
Adaptive Beamformers
8
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.. Wiener
.. MVDR
..
.. Maximum Array Gain
..
LCMV
Tradeoff
viii
Contents
SNR Estimation
DOA Estimation
A Spectral Coherence Perspective
.
.
.
.. Definitions
.. Derivation of Optimal Beamformers
Problems
References
Differential Beamforming
Signal Model, Problem Formulation, and Array Model
Beampatterns
Front-to-back Ratios
Array Gains
Examples of Theoretical Differential Beamformers
First-order Design
Principle
9
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.. Design Examples
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.. Design Examples
. Third-order Design
..
.. Design Examples
.
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.. Design Examples
Problems
References
Principle
Second-order Design
Principle
Minimum-norm Beamformers
Principle
10
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Beampattern Design
Beampatterns Revisited
Nonrobust Approach
Robust Approach
Frequency-invariant Beampattern Design
Least-squares Method
Joint Optimization
Problems
References
Beamforming in the Time Domain
Signal Model and Problem Formulation
Broadband Beamforming
Performance Measures
Fixed Beamformers
11
.
.
.
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.. Delay and Sum
.. Maximum DF
.. Distortionless Maximum DF
Contents
ix
Adaptive Beamformers
.. Superdirective
.. Null Steering
.
.. Wiener
.. MVDR
.. Tradeoff
.. Maximum SNR
.. LCMV
.
..
.. Second Order
.. General Order
.. Hypercardioid
.. Supercardioid
Differential Beamformers
First Order
Problems
References
Index