Arik D. Brown - Active Electronically Scanned Arrays: Fundamentals and Applications

1. Chapter 2
2. Chapter 4
3. Chapter 7
4. Appendix E

1. Chapter 1
2. Chapter 2
3. Chapter 3
4. Chapter 4
5. Chapter 5
6. Chapter 6
7. Chapter 7
8. Appendix C
9. Appendix E
10. Appendix F
11. Appendix G

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Arik D. Brown, PhD

Copyright 2022 by The Institute of Electrical and Electronics Engineers, Inc. All rights reserved.

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Hardback ISBN: 9781119749059

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Cover Image: Graphic by Arik Brown

To God, my wife Nadine, my children Alexis and Joshua, my parents Rudy and Meredith, my ever-supportive family, and in particular, my grandfather, the late James Gibby Sr., whose love for education lives on through me. Love has motivated me, faith has activated me, the power of the Spirit has accelerated me, and wisdom has provided the navigation. Thanks, Pastor Mike.

For those unfamiliar with AESAs, they can seem very confusing and complicated. However, there are basic fundamental principles that drive how AESAs operate and what are key metrics for their performance. This book's goal is to provide the AESA beginner, whether a student, researcher, or practicing engineer, an understanding of why AESAs are critical technology, what are the primary subsystems in an AESA, key driving subsystem parameters that govern AESA performance, and various AESA topologies that are commonly implemented.

AESAs provide incredible capability working synergistically with downconverters, upconverters, exciters, and/or receivers. Having worked with AESAs for over 20 years, I have grown accustomed to thinking of the entire system from the AESA front-end elements to the backend electronics as the AESA, but in practice the AESA consists of the front-end array elements and the electronics used to provide signal conditioning, amplification, and beam steering. One of my colleagues (John Welch) and I had a friendly disagreement on what defined an AESA, and he'll be amused to know that I now agree with his definition. This discussion is relevant to this book as its chapters are organized in this manner.

focuses on the the beamformer. In practice, the beamformer can also be referred to as the RF manifold. This chapter will show how signals are distributed from the exciter and also how signals received from the array elements are combined together to form beams.

The final two chapters cover AESA cascaded performance and architectures that are common in AESA systems. provides patterns for various AESA topologies spanning AESAs with phase shifters, AESAs with true time delay, subarrayed AESAs, and elemental digitally beamformed AESAs. It concludes with an overview on adaptive beamforming and several pattern examples.

I have worked on various systems spanning radar, electronic warfare, communications, and SIGINT for over 20 years. I have found that no matter what the application, the fundamentals remain the fundamentals. My hope is that these fundamentals are brought to light and made tangible to the reader uninitiated to AESA technology. Also, my goal is that those who are or have worked on AESAs will find utility in this book for explaining topics that in a normal busy day they have no time to research or investigate. As a system architect, I have had to take system level requirements and derive lower-level requirements that directly affect an AESA. I bring some of that flavor in the following chapters.

Maryland

March, 2021

Arik D. Brown

To the many great people who have imparted wisdom to me on my journey, and especially Dr. John Volakis, Dr. Leo Kempel, Uncle Bill (Bill Hopwood), Lee Cole, Carl Nothnick, John Wotjowitcz Sr., Rich Konapelsky, Dr. Daniel Boeringer, Dr. Eric Holzman, Dan Davis, Steve Pettit, Clint Ung, and Bob Worley.

Arik D. Brown