Wideband Beamforming Concepts and Techniques

Wideband beamforming has advanced with the increasing bandwidth in wireless communications and the development of ultra wideband (UWB) technology.

In this book, the authors address the fundamentals and most recent developments in the field of wideband beamforming. The book provides a thorough coverage of the subject including major sub-areas such as sub-band adaptive beamforming, frequency invariant beamforming, blind wideband beamforming, beamforming without temporal processing, and beamforming for multi-path signals.

Key Features:

• Unique book focusing on wideband beamforming
• Discusses a hot topic coinciding with the increasing bandwidth in wireless communications and the development of UWB technology
• Addresses the general concept of beamforming including fixed beamformers and adaptive beamformers
• Covers advanced topics including sub-band adaptive beamforming, frequency invariant beamforming, blind wideband beamforming, beamforming without temporal processing, and beamforming for multi-path signals
• Includes various design examples and corresponding complexity analyses

This book provides a reference for engineers and researchers in wireless communications and signal processing fields. Postgraduate students studying signal processing will also find this book of interest.

Acknowledgements

1 Introduction

1.1 Array Signal Processing

1.2 Narrowband Beamforming

1.3 Wideband Beamforming

1.4 Wideband Beam Steering

1.5 Summary

2 Adaptive Wideband Beamforming

2.1 Reference Signal-Based Beamformer

2.2 Linearly Constrained Minimum Variance Beamforming

2.3 Constraints Design for LCMV Beamforming

2.4 Generalized Sidelobe Canceller

2.5 Other Minimum Variance Beamformers

2.6 Robust Adaptive Beamforming

2.7 Summary

3 Subband Adaptive Beamforming

3.1 Fundamentals of Filter Banks

3.2 Subband Adaptive Filtering

3.3 General Subband Adaptive Beamforming

3.4 Subband Adaptive GSC

3.5 Temporally/Spatially Subband-Selective Beamforming

3.6 Frequency-Domain Adaptive Beamforming

3.7 Transform-Domain Adaptive Beamforming

3.8 Summary

4 Design of Fixed Wideband Beamformers

4.1 Iterative Optimization

4.2 The Least Squares Approach

4.3 The Eigenfilter Approach

4.4 Summary

5 Frequency Invariant Beamforming

5.1 Introduction

5.2 Design Based on Multi-Dimensional Inverse Fourier Transform

5.3 Subband Design of Frequency Invariant Beamformers

5.4 Frequency Invariant Beamforming for Circular Arrays

5.5 Direct Optimization for Frequency Invariant Beamforming

5.6 Beamspace Adaptive Wideband Beamforming

5.7 Summary

6 Blind Wideband Beamforming

6.1 Blind Source Separation

6.2 Blind Wideband Beamforming

6.3 Blind Beamforming Based on Frequency Invariant Transformation

6.4 Summary

7 Wideband Beamforming with Sensor Delay-Lines

7.1 Sensor Delay-Line Based Structures

7.2 Frequency Invariant Beamforming

7.3 Adaptive Beamforming

7.4 Beamspace Adaptive Beamforming

7.5 Summary

8 Wideband Beamforming for Multipath Signals

8.1 The Wideband Multipath Problem

8.2 Approach Based on a Narrowband Beamformer

8.3 Approach Based on Blind Source Separation

8.4 MIMO System

8.5 Summary

Appendix A: Matrix Approximation

Appendix B: Differentiation with Respect to a Vector

Appendix C: Generic Algorithm

C.1 The Principle

C.2 Design Example in Section 3.5.2

Bibliography

Index