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Radar Handbook, Third Edition
ii ABOUT THE EDITOR IN CHIEF Merrill Skolnik was Superintendent of the Radar Division at the U.S. Naval Research Labora
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ABOUT THE EDITOR IN CHIEF Merrill Skolnik was Superintendent of the Radar Division at the U.S. Naval Research Laboratory for over 30 years. Before that he was involved in advances in radar while at the MIT Lincoln Laboratory, the Institute for Defense Analyses, and the Research Division of Electronic Communications, Inc. He is the author of the popular McGraw-Hill textbook Introduction to Radar Systems, now in its third edition, the editor of Radar Applications, as well as being a former editor of the Proceedings of the IEEE. He earned the Doctor of Engineering Degree from The Johns Hopkins University, where he also received the B.E and M.S.E degrees in electrical engineering. He is a member of the U.S. National Academy of Engineering, a Fellow of the IEEE, and the first recipient of the IEEE Dennis J. Picard Medal for Radar Technologies and Applications.
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RADAR HANDBOOK Merrill I. Skolnik Editor in Chief Third Edition
New York Chicago San Francisco Lisbon London Madrid Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto
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Cataloging-in-Publication Data is on file with the Library of Congress McGraw-Hill books are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs. To contact a representative, please visit the Contact Us pages at www.mhprofessional.com. Radar Handbook, Third Edition Copyright © 2008 by The McGraw-Hill Companies. All rights reserved. Printed in the United States of America. Except as permitted under the Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of publisher. 1 2 3 4 5 6 7 8 9 0 DOC DOC 0 1 9 8 ISBN 978-0-07-148547-0 MHID 0-07-148547-3 Sponsoring Editor Wendy Rinaldi Editorial Supervisor Janet Walden Project Editor LeeAnn Pickrell Acquisitions Coordinator Mandy Canales Copy Editor LeeAnn Pickrell Proofreader Susie Elkind Production Supervisor Jean Bodeaux Composition International Typesetting & Composition Illustration International Typesetting & Composition Art Director, Cover Jeff Weeks Cover Designer Mary McKeon Information has been obtained by McGraw-Hill from sources believed to be reliable. However, because of the possibility of human or mechanical error by our sources, McGraw-Hill, or others, McGraw-Hill does not guarantee the accuracy, adequacy, or completeness of any information and is not responsible for any errors or omissions or the results obtained from the use of such information.
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CONTENTS Contributors Preface Chapter 1 An Introduction and Overview of Radar Merrill Skolnik 1.1 Radar in Brief /
xiii xv 1.1 1.1
1.2 Types of Radars /
1.5
1.3 Information Available from a Radar /
1.7
1.4 The Radar Equation /
1.10
1.5 Radar Frequency Letter-band Nomenclature /
1.13
1.6 Effect of Operating Frequency on Radar /
1.14
1.7 Radar Nomenclature /
1.18
1.8 Some Past Advances in Radar /
1.19
1.9 Applications of Radar /
1.20
1.10 Conceptual Radar System Design /
1.22
Chapter 2 MTI Radar William W. Shrader and Vilhelm Gregers-Hansen 2.1 Preface /
2.1 2.1
2.2 Introduction to MTI Radar /
2.2
2.3 Clutter Filter Response to Moving Targets /
2.9
2.4 Clutter Characteristics /
2.10
2.5 Definitions /
2.19
2.6 Improvement Factor Calculations /
2.23
2.7 Optimum Design of Clutter Filters /
2.25
2.8 MTI Clutter Filter Design /
2.33
2.9 MTI Filter Design for Weather Radars /
2.46
2.10 Clutter Filter Bank Design /
2.52
2.11 Performance Degradation Caused by Receiver Limiting /
2.59
2.12 Radar System Stability Requirements /
2.65
2.13 Dynamic Range and A/D Conversion Considerations /
2.78
2.14 Adaptive MTI /
2.80
2.15 Radar Clutter Maps /
2.83
2.16 Sensitivity-velocity Control (SVC) /
2.87
2.17 Considerations Applicable to MTI Radar Systems /
2.91
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Chapter 3 Airborne MTI James K. Day and Fred M. Staudaher 3.1 Systems Using Airborne MTI Techniques /
3.1 3.1
3.2 Coverage Considerations /
3.2
3.3 Airborne MTI Performance Drivers /
3.3
3.4 Platform Motion and Altitude Effects on MTI Performance /
3.3
3.5 Platform-motion Compensation Abeam /
3.10
3.6 Scanning-motion Compensation /
3.14
3.7 Simultaneous Platform Motion and Scan Compensation /
3.18
3.8 Platform-motion Compensation, Forward Direction /
3.21
3.9 Space-time Adaptive Motion Compensation /
3.23
3.10 Effect of Multiple Spectra /
3.31
3.11 Example AMTI Radar System /
3.32
Chapter 4 Pulse Doppler Radar John P. Stralka and William G. Fedarko 4.1 Characteristics and Applications /
4.1 4.1
4.2 Pulse Doppler Clutter /
4.14
4.3 Dynamic-range and Stability Requirements /
4.24
4.4 Range and Doppler Ambiguity Resoluton /
4.31
4.5 Mode and Waveform Design /
4.35
4.6 Range Performance /
4.39
List of Abbreviations /
4.48
Chapter 5 Multifunctional Radar Systems for Fighter Aircraft David Lynch, Jr. and Carlo Kopp 5.1 Introduction /
5.1 5.1
5.2 Typical Missions and Modes /
5.10
5.3 A-A Mode Descriptions & Waveforms /
5.16
5.4 A-S Mode Descriptions & Waveforms /
5.28
Chapter 6 Radar Receivers Michael E. Yeomans 6.1 The Configuration of a Radar Receiver /
6.1 6.1
6.2 Noise and Dynamic-range Considerations /
6.4
6.3 Bandwidth Considerations /
6.9
6.4 Receiver Front End /
6.10
6.5 Local Oscillators /
6.14
6.6 Gain Control /
6.22
6.7 Filtering /
6.24
6.8 Limiters /
6.29
6.9 I/Q Demodulators /
6.31
6.10 Analog-to-Digital Converters /
6.35
6.11 Digital Receivers /
6.40
6.12 Diplex Operation /
6.46
6.13 Waveform Generation and Upconversion /
6.47
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Chapter 7 Automatic Detection, Tracking, and Sensor Integration W. G. Bath and G. V.Trunk 7.1 Introduction /
7.1 7.1
7.2 Automatic Detection /
7.1
7.3 Automatic Tracking /
7.22
7.4 Networked Radars /
7.46
7.5 Unlike-sensor Integration /
7.49
Chapter 8 Pulse Compression Radar Michael R. Ducoff and Byron W. Tietjen 8.1 Introduction / 8.2 Pulse Compression Waveform Types /
8.1 8.1 8.2
8.3 Factors Affecting Choice of Pulse Compression Systems /
8.26
8.4 Pulse Compression Implementation and Radar System Examples /
8.28
Appendix / Chapter 9 Tracking Radar Dean D. Howard 9.1 Introduction / 9.2 Monopulse (Simultaneous Lobing) /
8.36 9.1 9.1 9.3
9.3 Scanning and Lobing /
9.16
9.4 Servosystems for Tracking Radar /
9.17
9.5 Target Acquisition and Range Tracking /
9.20
9.6 Special Monopulse Techniques /
9.24
9.7 Sources of Error /
9.26
9.8 Target-caused Errors (Target Noise) /
9.26
9.9 Other External Causes of Error /
9.37
9.10 Internal Sources of Error /
9.42
9.11 Summary of Sources of Error /
9.43
9.12 Error Reduction Techniques /
9.46
Chapter 10 The Radar Transmitter Thomas A. Weil and Merrill Skolnik 10.1 Introduction /
10.1
10.2 Linear-beam Amplifiers /
10.1 10.4
10.3 Magnetron /
10.14
10.4 Crossed-field Amplifiers /
10.16
10.5 Gyrotrons /
10.17
10.6 Transmitter Spectrum Control /
10.19
10.7 Grid-controlled Tubes /
10.21
10.8 Modulators /
10.23
10.9 Which RF Power Source to Use? /
10.25
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Chapter 11 Solid id-State Transmitters Michael T. Borkowski 11.1 Introduction /
11.1 11.1
11.2 Advantages of Solid State /
11.1
11.3 Solid-state Devices /
11.5
11.4 Designing for the Solid-state Bottle Transmitter /
11.17
11.5 Designing for the Solid-state Phased Array Transmitter /
11.24
11.6 Solid-state System Examples /
11.37
Chapter 12 Reflector Antennas Michael E. Cooley and Daniel Davis 12.1 Introduction /
12.1 12.7
12.2 Basic Principles and Parameters /
12.3
12.3 Reflector Antenna Architectures /
12.16
12.4 Reflector Feeds /
12.25
12.5 Reflector Antenna Analysis /
12.37
12.6 Mechanical Design Considerations /
12.35
Acknowledgments / Chapter 13 Phased Array Radar Antennas Joe Frank and John D. Richards 13.1 Introduction / 13.2 Array Theory /
12.47 13.1 13.7 13.9
13.3 Planar Arrays and Beam Steering /
13.15
13.4 Aperture Matching and Mutual Coupling /
13.20
13.5 Low-sidelobe Phased Arrays /
13.28
13.6 Quantization Effects /
13.34
13.7 Bandwidth of Phased Arrays /
13.38
13.8 Feed Networks (Beamformers) /
13.46
13.9 Phase Shifters /
13.57
13.10 Solid-state Modules /
13.53
13.11 Multiple Simultaneous Receive Beams /
13.54
13.12 Digital Beamforming /
13.56
13.13 Radiation Pattern Nulling /
13.57
13.14 Calibration of Active Phased Array Antennas /
13.60
13.15 Phased Array Systems /
13.62
Chapter 14 Radar Cross Section Eugene F. Knott 14.1 Introduction /
14.1 14.1
14.2 The Concept of Echo Power /
14.4
14.3 RCS Prediction Techniques /
14.16
14.4 RCS Measurement Techniques /
14.27
14.5 Radar Echo Suppression /
14.36
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Chapter 15 Sea Clutter Lewis B. Wetzel 15.1 Introduction /
15.1 15.1
15.2 The Sea Surface /
15.3
15.3 Empirical Behavior of Sea Clutter /
15.7
15.4 Theories and Models of Sea Clutter /
15.27
15.5 Summary and Conclusions /
15.37
Chapter 16 Ground Echo Richard K. Moore 16.1 Introduction /
16.1 16.1
16.2 Parameters Affecting Ground Return /
16.4
16.3 Theoretical Models and Their Limitations /
16.7
16.4 Fading of Ground Echoes /
16.12
16.5 Measurement Techniques for Ground Return /
16.19
16.6 General Models for Scattering Coefficient (Clutter Models) /
16.29
16.7 Scattering Coefficient Data /
16.35
16.8 Polarimetry /
16.46
16.9 Scattering Coefficient Data Near Grazing /
16.52
16.10 Imaging Radar Interpretation /
16.55
Chapter 17 Synthetic Aperture Radar Roger Sullivan 17.1 Basic Principle of SAR /
17.1 17.1
17.2 Early History of SAR /
17.2
17.3 Types of SAR /
17.2
17.4 SAR Resolution /
17.6
17.5 Key Aspects of SAR /
17.10
17.6 SAR Image Quality /
17.16
17.7 Summary of Key SAR Equations /
17.21
17.8 Special SAR Applications /
17.22
Chapter 18 Space-Based Remote Sensing Radars R. Keith Raney 18.1 Perspective / 18.2 Synthetic Aperture Radar (SAR) /
18.1 18.1 18.5
18.3 Altimeters /
18.29
18.4 Planetary Radars /
18.43
18.5 Scatterometers /
18.53
18.6 Radar Sounders /
18.59
x
Chapter 19 Meteorological Radar R. Jeffrey Keeler and Robert J. Serafin 19.1 Introduction /
19.1 19.1
19.2 The Radar Equation for Meteorological Targets /
19.3
19.3 Design Considerations /
19.6
19.4 Signal Processing /
19.19
19.5 Operational Applications /
19.25
19.6 Research Applications /
19.33
Chapter 20 HF Over-the-Horizon Radar James M. Headrick and Stuart J. Anderson 20.1 Introduction /
20.1
20.2 The Radar Equation /
20.5
20.3 Factors Influencing Skywave Radar Design /
20.7
20.4 The Ionosphere and Radiowave Propagation /
20.13
20.5 Waveforms for HF Radar /
20.21
20.6 The Transmitting System /
20.23
20.7 Radar Cross Section /
20.26
20.8 Clutter: Echoes from the Environment /
20.29
20.9 Noise, Interference, and Spectrum Occupancy /
20.40
20.10 The Receiving System /
20.45
20.11 Signal Processing and Tracking /
20.49
20.12 Radar Resource Management /
20.54
20.13 Radar Performance Modeling /
20.55
Appendix: HF Surface Wave Radar /
20.70
Chapter 21 Ground Penetrating Radar David Daniels 21.1 Introduction / 21.2 Physics of Propagation in Materials /
20.1
21.1 21.1 21.6
21.3 Modeling /
21.13
21.4 Properties of Materials /
21.18
21.5 GPR Systems /
21.20
21.6 Modulation Techniques /
21.21
21.7 Antennas /
21.24
21.8 Signal and Image Processing /
21.30
21.9 Applications /
21.35
21.10 Licensing /
21.39
Chapter 22 Civil Marine Radar Andy Norris 22.1 Introduction /
22.1 22.1
22.2 The Challenges /
22.3
22.3 International Standards /
22.7
22.4 Technology /
22.10
22.5 Target Tracking /
22.17
xi
22.6 User Interface /
22.19
22.7 Integration with AIS /
22.23
22.8 Radar Beacons /
22.25
22.9 Validation Testing /
22.28
22.10 Vessel Tracking Services /
22.29
Appendix The Early Days of CMR /
22.31
List of Maritime Radar-related Abbreviations /
22.33
Acknowledgments /
22.34
Chapter 23 Bistatic Radar Nicholas J. Willis 23.1 Concept and Definitions /
23.1 23.1
23.2 Coordinate Systems /
23.3
23.3 Bistatic Radar Equation /
23.4
23.4 Applications /
23.9
23.5 Bistatic Doppler /
23.14
23.6 Target Location /
23.17
23.7 Target Cross Section /
23.19
23.8 Surface Clutter /
23.22
23.9 Unique Problems and Requirements /
23.26
Chapter 24 Electronic Counter-Countermeasures Alfonso Farina 24.1 Introduction /
24.1 24.1
24.2 Terminology /
24.2
24.3 Electronic Warfare Support Measures /
24.2
24.4 Electronic Countermeasures /
24.5
24.5 Objectives and Taxonomy of ECCM Techniques /
24.8
24.6 Antenna-related ECCM /
24.10
24.7 Transmitter-related ECCM /
24.31
24.8 Receiver-related ECCM /
24.32
24.9 Signal-processing-related ECCM /
24.33
24.10 Operational-deployment Techniques /
24.36
24.11 Application of ECCM Techniques /
24.37
24.12 ECCM and ECM Efficacy /
24.54
Acronym List /
24.56
Acknowledgments /
24.58
Chapter 25 Radar Digital Signal Processing James J. Alter and Jeffrey O. Coleman 25.1 Introduction /
25.1 25.1
25.2 Receive Channel Processing /
25.2
25.3 Transmit Channel Processing /
25.20
25.4 DSP Tools /
25.22
25.5 Design Considerations /
25.34
25.6 Summary /
25.37
Acknowledgments /
25.38
xii
Chapter 26 The Propagation Factor, Fp, in the Radar Equation Wayne L. Patterson 26.1 Introduction /
26.1 26.1
26.2 The Earth’s Atmosphere /
26.2
26.3 Refraction /
26.3
26.4 Standard Propagation /
26.4
26.5 Anomalous Propagation /
26.6
26.6 Propagation Modeling /
26.13
26.7 EM System Assessment Programs /
26.18
26.8 AREPS Radar System Assessment Model /
26.23
26.9 AREPS Radar Displays /
26.25
Index
1.1
xiii
CONTRIBUTORS James J. Alter Naval Research Laboratory (CHAPTER 25) Stuart J. Anderson Australian Defense Science and Technology Organisation (CHAPTER 20) W. G. Bath The Johns Hopkins University Applied Physics Laboratory (CHAPTER 7) Michael T. Borkowski Raytheon Company (CHAPTER 11) Jeffrey O. Coleman Naval Research Laboratory (CHAPTER 25) Michael E. Cooley Northrop Grumman, Electronic Systems (CHAPTER 12) David Daniels ERA Technology (CHAPTER 21) Daniel Davis Northrop Grumman Corporation (CHAPTER 12) James K. Day Lockheed Martin Corporation (CHAPTER 3) Michael R. Ducoff Lockheed Martin Corporation (CHAPTER 8) Alfonso Farina SELEX Sistemi Integrati (CHAPTER 24) William G. Fedarko Northrop Grumman Corporation (CHAPTER 4) Joe Frank The Johns Hopkins University Applied Physics Laboratory (CHAPTER 13) Vilhelm Gregers-Hansen Naval Research Laboratory (CHAPTER 2) James M. Headrick Naval Research Laboratory, retired (CHAPTER 20) Dean D. Howard Consultant to ITT Industries, Inc. (CHAPTER 9) R. Jeffrey Keeler National Center for Atmospheric Research (CHAPTER 19) Eugene F. Knott Tomorrow’s Research (CHAPTER 14) Carlo Kopp Monash University (CHAPTER 5) David Lynch, Jr. DL Sciences, Inc. (CHAPTER 5) Richard K. Moore The University of Kansas (CHAPTER 16) Andy Norris Consultant in Navigation Systems (CHAPTER 22) Wayne L. Patterson Space and Naval Warfare Systems Center (CHAPTER 26) Keith Raney The Johns Hopkins University Applied Physics Laboratory (CHAPTER 18) John D. Richards The Johns Hopkins University Applied Physics Laboratory (CHAPTER 13) Robert J. Serafin National Center for Atmospheric Research (CHAPTER 19) William W. Shrader Shrader Associates (CHAPTER 2) Merrill Skolnik (CHAPTERS 1 and 10) Fred M. Staudaher Naval Research Laboratory, retired (CHAPTER 3)
xiv
John P. Stralka Northrop Grumman Corporation (CHAPTER 4) Roger Sullivan Institute for Defense Analyses (CHAPTER 17) Byron W. Tietjen Lockheed Martin Corporation (CHAPTER 8) G. V. Trunk The Johns Hopkins University Applied Physics Laboratory (CHAPTER 7) Thomas A. Weil (CHAPTER 10) Lewis B. Wetzel Naval Research Laboratory, retired (CHAPTER 15) Nicholas J. Willis Technology Service Corporation, retired (CHAPTER 23) Michael E. Yeomans Raytheon Company (CHAPTER 6)
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PREFACE Radar is an important example of an electrical engineering system. In university engineering courses, the emphasis usually is on the basic tools of the electrical engineer such as circuit design, signals, solid state, digital processing, electronic devices, electromagnetics, automatic control, microwaves, and so forth. But in the real world of electrical engineering practice, these are only the techniques, piece parts, or subsystems that make up some type of system employed for a useful purpose. In addition to radar and other sensor systems, electrical engineering systems include communications, control, energy, information, industrial, military, navigation, entertainment, medical, and others. These are what the practice of electrical engineering is all about. Without them there would be little need for electrical engineers. However, the practicing engineer who is involved in producing a new type of electrical engineering system often has to depend on acquiring knowledge that was not usually covered in his or her engineering courses. The radar engineer, for example, has to understand the major components and subsystems that make up a radar, as well as how they fit together. The Radar Handbook attempts to help in this task. In addition to the radar system designer, it is hoped that those who are responsible for procuring new radar systems, those who utilize radars, those who maintain radar systems, and those who manage the engineers who do the above, also will find the Radar Handbook to be of help in fulfilling such tasks. The third edition of the Radar Handbook is evidence that the development and application of radar for both civilian and military purposes continue to grow in both utility and in improved technology. Some of the many advances in radar since the previous edition include the following: - The extensive use of digital methods for improved signal processing, data processing, decision making, flexible radar control, and multifunction radar - Doppler weather radar - Ground moving target indication, or GMTI - An extensive experimental database describing low-angle land clutter, as obtained by MIT Lincoln Laboratory, that replaced the previously widely used clutter model that dated back to World War II - The realization that microwave sea echo at low grazing angles is due chiefly to what are called “sea spikes” - The active-aperture phased array radar system using solid-state modules, also called active electronically scanned arrays (AESA), which is attractive for some multifunction radar applications that need to manage both power and spatial coverage - Planetary exploration with radar - Computer-based methods for predicting radar propagation performance in realistic environments
xvi
- Operational use of HF over-the-horizon radar - Improved methods for detecting moving targets in clutter, including space-time adaptive processing - Operational use of inverse synthetic aperture radar for target recognition - Interferometric synthetic aperture radar, or InSAR, to obtain the height of a resolved scatterer or to detect moving ground targets as well as provide a SAR image of a scene - High precision space-based altimeters, with accuracy of a few centimeters, to measure the Earth’s geoid - Ultrawideband radar for ground penetrating and similar applications - Improved high power, wide bandwidth klystron power sources based on clustered cavity resonators, as well as the multiple-beam klystron - The appearance of wide bandgap semiconductors that allow better performance because of high power and high operating temperatures - The availability of high-power millimeter-wave generators based on the gyroklystron - Nonlinear FM pulse compression with low sidelobe levels - The replacement, by the computer, of the operator as information extractor and decision maker The above are not listed in any particular order, nor should they be considered a complete enumeration of radar developments since the appearance of the previous edition. There were also some radar topics in previous editions of the Radar Handbook that are of lesser interest and so were not included in this edition. The chapter authors, who are experts in their particular field, were told to consider the reader of their chapter as being knowledgeable in the general subject of radar and even an expert in some other particular area of radar, but not necessarily knowledgeable about the subject of the particular chapter the author was writing. It should be expected that with a book in print as long as the Radar Handbook has been, not all chapter authors from the previous editions would be available to do the third edition. Many of the previous authors have retired or are no longer with us. Sixteen of the twenty-six chapters in this edition have authors or coauthors who were not involved in the previous editions. The hard work of preparing these chapters was done by the individual expert authors of the various chapters. Thus the value of the Radar Handbook is the result of the diligence and expertise of the authors who contributed their time, knowledge, and experience to make this handbook a useful addition to the desk of radar system engineers and all those people vital to the development, production, and employment of radar systems. I am deeply grateful to all the contributing authors for their fine work and the long hours they had to apply to their task. It is the chapter authors who make any handbook a success. My sincere thanks to them all. As stated in the Preface of the previous edition, readers who wish to reference or quote material from the Radar Handbook are asked to mention the names of the individual chapter authors who produced the material. MERRILL SKOLNIK Baltimore, Maryland
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MOUNTEDONTHEAIRCRAFTSWINGTIPASFARAPARTASPOSSIBLE4HESIGNALSRECEIVEDINEACH WINGTIPANTENNAAREREPEATEDINTHEOPPOSITEWINGTIPANTENNA EXCEPTFORAnPHASE SHIFT WHICHISINSERTEDINONELINETODIRECTANINTERFEROMETRICNULLTOWARDTHEVICTIM RADAR)NEFFECT THISCREATESANAPPARENTCHANGEOFTARGETDIRECTIONASVIEWEDFROMTHE RADAR!LARGEREPEATERGAINISREQUIREDTOGENERATEAHIGHJAMMER TO SIGNALRATIOOTH ERWISE THESKINECHOWILLOVERWHELMTHEJAMMINGSIGNALSINTHEINTERFEROMETERPATTERN NULLS4HEMAXIMUMEFFECTIVENESSOFTHETECHNIQUEIMPLIESACONSIDERABLEDELAYON THEORDEROFNS INTHEREPEATEDSIGNAL OWINGTOTHETRANSMISSIONLINEANDAMPLIFIER BETWEENTHERECEIVERANDTRANSMITTERANTENNAS4HUS LEADING EDGEORMULTIGATERANGE TRACKINGSHOULDBEANEFFECTIVE%##-TECHNIQUEAGAINSTCROSS EYEJAMMING 4ERRAIN BOUNCE JAMMING OR TERRAIN SCATTERED INTERFERENCE 43) OR HOT CLUTTER IS ANOTHERMONOPULSEJAMMINGTECHNIQUETHATISUSEDAGAINSTSEMIACTIVEMISSILESEEKERS ANDAIRBORNETRACKINGRADARS7ITHTHISTECHNIQUE THEJAMMERAIRCRAFTILLUMINATESTHE %ARTHSSURFACEINFRONTOFANDBELOWIT SOTHATTHESEMIACTIVEMISSILEHOMESONTHE ILLUMINATEDGROUNDSPOTANDNOTONTHEJAMMERAIRCRAFT4HEUNCERTAINTYOFTHETERRAIN SCATTERINGPARAMETERSANDTHEPOSSIBLEDEPOLARIZINGEFFECTSOFSURFACEREFLECTIONARE SOMEOFTHEPROBLEMSASSOCIATEDWITHTHISTECHNIQUE 4HE43) AGAINST AIRBORNE RADAR AND THE CORRESPONDING MITIGATION TECHNIQUES ARE DESCRIBEDINDETAILINTHELITERATUREn43)ISASIGNIFICANTPROBLEMTOMILITARYAIR BORNE RADAR IN FACT AN OFTEN WEAK TARGET SIGNAL IN THE MAIN BEAM HAS TO COMPETE WITHJAMMERTHATPROPAGATESNOTONLYVIADIRECT PATHBUTALSOVIAMULTIPATHFROMTHE UNDERLYINGTERRAIN-ITIGATIONTECHNIQUESHAVEBEENFOCUSEDONESTIMATINGTHEDIRECT JAMMERSIGNAL ESTIMATINGTHELINEARSYSTEMCREATEDBYTHEMULTIPATH ANDREMOVING ANESTIMATEOFTHEREFLECTEDJAMMERSIGNALFROMTHEMAINRECEIVEDRADARSIGNALTHIS ISALSOALLOWEDBYUSINGREFERENCEBEAMSPOINTEDATHOTCLUTTER!DAPTIVECANCELLA TIONTECHNIQUESHAVETOBEABLETOACCOUNTFORTHEDOPPLERINDUCEDBYRELATIVEMOTION BETWEENAIRBORNERADARANDJAMMERPLATFORMSANDTHEJAMMERSIGNALNONSTATIONARITY THATISPRODUCEDFROMSUCHABISTATICGEOMETRY43)MITIGATIONFOROVER THE HORIZON /4( RADARISDESCRIBEDIN!BRAMOVICHETAL -ONOPULSERADARSTHATUSEPARABOLICREFLECTORANTENNASARESUSCEPTIBLETOJAMMING THROUGH CROSS POLARIZATION LOBES GENERATED BY THE REFLECTOR SURFACE 4HIS OCCURS BECAUSETHEANGLE ERROR SENSINGDISCRIMINATORHASANINVERSESLOPEFORACROSS POLARIZED SIGNAL WHICHCAUSESTHEANGLE TRACKINGSERVOTOHAVEPOSITIVEFEEDBACKINSTEADOFTHE NEGATIVEFEEDBACKREQUIREDFORTRACKING-ONOPULSEESTIMATESWITHPLANARARRAYANTEN NASUSUALLYHAVEAHIGHRESISTANCETOCROSS POLARIZATIONJAMMINGSEE3ECTIONOF 7IRTH 7ITHARRAYANTENNASINCONTRASTTOREFLECTORANTENNASALLTHESINGLEANTENNA ELEMENTSHAVETHESAMEPOLARIZATION DEPENDENTPATTERN4HISISMULTIPLIEDWITHTHEARRAY FACTORANDALSOAPPLIESFORTHESUMANDDIFFERENCEPATTERNS4HERESULTANTFORMOFTHE BEAMPATTERNWILLTHUSBEINDEPENDENTOFPOLARIZATION4HEREFORE THEMONOPULSEOPERA TIONWILLALSONOTBEDISTURBED 0HASED !RRAY2ADARS )NTHISSUBSECTION WEILLUSTRATE BYANUMERICALEXAM PLE THEROLEPLAYEDBYTHESCHEDULERINAMULTIFUNCTIONAL0!2TOCOMBAT%#-4OTHIS END WERESORTTOABENCHMARKSTUDYDESCRIBEDINTHELITERATURE WHICHDEFINESTYPICAL %#-THREATS OPERATIONALSCENARIOS ANDPHASED ARRAYPERFORMANCEMAINLYINTERMS OF TARGET TRACKING UNDER %#- 4HE SIMULATION BENCHMARK INCLUDES TWO TYPES OF %#- NAMELY3/*AND2'0/4HE3/* MOUNTEDONANAIRCRAFT TRANSMITSBROADBAND NOISETOWARDTHERADAR4HE3/*FLIESANOVALRACECOURSE HOLDINGPATTERNINACLOCK WISEDIRECTIONATANALTITUDEOFMANDASPEEDOFMSITISAPPROXIMATELY
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I_1
INDEX
A A-12 low cross section aircraft, 14.40 Absorbers, 14.32, 14.36 to 14.38 Active aperture, 13.53 to 13.55 Active Electronically Scanned Array (AESA), 5.1, 5.8 to 5.10, 10.28 compared to mechanical scan, 5.9 to 5.10 timing structure, 5.15 to 5.16 typical waveform parameters, 5.13, 5.15 waveform variations for air-to-surface mode, 5.12 to 5.13 Active jamming, 24.5 Active-switch modulator, 10.24 A/D converter and MTI dynamic range, 2.78 to 2.80 Adaptive arrays (ECCM), 24.20 to 24.30 Adaptive jammer and clutter cancellation, 24.25 Adaptive MTI, 2.80 to 2.83 Adaptive thresholding, 7.11 to 7.19 Advanced Propagation Model (APM), 26.16 to 26.17 Advanced Refractive Effects Prediction System (AREPS), 26.1 to 26.2, 26.18 to 26.27 Aid to Navigation (AtoN), 22.25 to 22.26 Air-to-air ground ranging, 5.33 Air-to-air mission profile, 5.12 to 5.14 Air-to-air modes, 5.14, 5.16 to 5.28 medium PRF, 5.16 to 5.20 Air-to-surface mission profile, 5.10 Air-to-surface mode suite, 5.11 to 5.12 Air-to-surface radar modes, 5.28 to 5.42 Air-traffic control (ATC) radar, 1.21 to 1.22 Air Traffic Control Radar Beacon System (ATCRBS), 7.49 Airborne Early Warning, 3.1. See also Airborne Moving Target Indication antenna sidelobes, 3.13 to 3.14 coverage, 3.2 to 3.3 platform motion, 3.3 to 3.14 TACCAR, 3.4 to 3.9 Airborne Moving Target Indication (AMTI) example of, 3.32 to 3.33 improvement factor, 3.8 multiple spectra, 3.31 to 3.32 scanning motion compensation, 3.14 to 3.17 and STAP, 3.23 to 3.31 Aircraft radar cross section, 14.13 to 14.14 Alpha-beta (-) filter, 7.26 to 7.27, 7.30 Altimeters, from space, 18.33 to 18.57 Altitude line, 4.4 to 4.5 Ambiguity function, 8.40 Ambiguity resolution, in MTI, 2.89 to 2.91 Amplitude-comparison monopulse, 9.3 to 9.11 Amplitude noise, in tracking, 9.27 to 9.30 AN/APG-76, 17.25 AN/APY-9, 3.32 to 3.33 AN/FPQ-6, 9.2, 9.9, 9.18, 9.21, 9.44 AN/FPS-23, 23.7 AN/EPS-117, 8.30, 13.63 to 13.64 AN/MPS-39, 9.2, 9.26 AN/SPS-40, 10.27, 11.32 to 11.33 AN/SPY-1, 13.62
AN/SPY-3, 13.69 AN/TPS-59, 8.30, 13.63 to 13.64 AN/TPS-63, 12.18 AN/TPS-77, 13.63 to 13.64 AN/TPS-78, 13.65 to 13.66 Analog-to-digital (A/D) converters, 6.35 to 6.40
I_2
Anechoic chamber, 14.32 Angle accuracy, by beam splitting, 7.5 to 7.7 Angle measurement errors, 9.43 to 9.44 Angle noise, 9.30 to 9.35 Angle scintillation (glint), 9.30 to 9.35, 9.47 Angular direction, 1.8 Anomalous propagation, 26.6 to 26.13 Antenna-related ECCM, 24.10 to 24.31 Antennas, 1.2, 1.4 to 1.5. See also phased arrays, reflector antennas basic principles, 12.3 to 12.15 for civil marine radar, 22.10 to 22.12 for ground penetrating radar, 21.24 to 21.30 phased array, 13.2 to 13.3 for pulse doppler, 4.12 to 4.13 reflector antennas, role of, 12.1 reflector antennas, types of, 12.7 Anti-radiation missile (ARM), 24.40 Anti-range-gate pull-off (A-RGPO), 24.46 Aperture gain, of antennas, 12.4 to 12.5 Apollo Lunar Sounder, 18.60 to 18.61 Aquarius scatterometer, 18.58 Area MTI, 2.84 Array feeds, for reflector antennas, 12.28 to 12.30 ARSR-4, 12.30 ASR-9, 10.27 to 10.28, 12.20 to 12.21 ASR-11 MTI filter design, 2.50 to 2.51 ASR-12, 8.30, 10.27 to 10.28 Atmosphere, of the Earth, 26.2 Atmospheric ducts, 26.7 to 26.10 Attenuation, by clouds, 19.7 to 19.8 by fog, 19.12 by hail, 19.11 to 19.12 by rain, 19.8 to 19.11 Automatic detection, 7.1 to 7.2, 7.20 to 7.22 Automatic gain control (AGC), in monopulse tracker, 9.5, 9.10 to 9.11 Automatic Identification System (AIS) in civil marine radar, 22.23 to 22.25 in search and rescue, 22.27 Automatic noise-level control, 6.23 to 6.24 Automatic Radar Plotting Aid (ARPA), 22.17 Automatic tracking, 7.22 to 7.46 alpha-beta (-) filter, 7.26 to 7.27, 7.30 detection acceptance, 7.25 to 7.26 Interacting Multiple Model (IMM), 7.35 to 7.37 Kalman filter, 7.28 to 7.35 new track formation, 7.41 to 7.46 retrospective processing, 7.42 to 7.43 scheduling and control, 7.46 track association, 7.38 to 7.41 track file, 7.23 to 7.25 updating tracks, 7.26 to 7.30 AWACS, 13.65
B B-2 low cross section aircraft, 14.18, 14.42 Ballistic missile defense, 13.54 Bandwidth importance of, 1.8 to 1.9 of phased arrays, 13.38 to 13.45 receiver, 6.9 Bar, in airborne radar, 5.15 to 5.16 Barker codes, 8.17
Batch processor, 7.8 to 7.11 Battle of the Pips, ducting effects, 26.9 Beacon equation, 24.4 Beacon rendezvous, 5.27 Beam-shape factor, 7.3 Beam-shape loss, 4.40 Beam-splitting angle accuracy, 7.5 to 7.7 Beam steering, 13.15 to 13.19 Beam steering control, 5.10 Binary integrator, 7.7 to 7.8, 7.12 to 7.13 Birds, and MTI, 2.96 to 2.98 Bistatic plane, 23.3 Bistatic radar applications, 23.9 to 23.14 benchmark range, 23.4 to 23.5 concept of, 23.1 to 23.3 coordinate system, 23.3 to 23.4 doppler in, 23.14 to 23.17 floodlight beams, 23.27 forward scatter, 23.21 glint in, 23.20 to 23.21 ground echo, 16.29 hitchhiker, 23.10 with noncooperative transmitter, 23.29 to 23.31 ovals of Cassini, 23.6 to 23.8 passive, 23.10 pseudo-monostatic region, 23.19 to 23.20 pulse chasing, 23.28 to 23.29
I_3
range equation, 23.5 to 23.6 SAR, 23.17 scattering coefficient, 23.22 to 23.25 surface clutter in, 23.22 to 23.26 target cross section, 23.19 to 23.21 target location, 23.17 to 23.19 with TV transmitter, 23.29 to 23.31 Blind speeds, 2.9 to 2.10 Block diagram digital receiver, 25.2 medium PRF air-to-air pulse doppler, 5.17 monopulse tracking radar, 9.4 to 9.5 Moving Target Detection, 2.6 to 2.7 multifunctional fighter aircraft radar, 5.3 pulse compression, 8.1 to 8.2 pulse doppler, 4.11 radar, 1.3 SBR altimeter, 18.40 Bodies of revolution radar cross section, 14.39 to 14.40 Bragg scatter, 15.2, 15.28 to 15.32, 15.38, and ground echo, 16.11 to 16.12 Burst mode, in SBR SAR, 18.23 to 18.24
C C band, 1.16 Calibrate and self-test, 5.42 Calibration of meteorological radar, 19.18 to 19.19 Cascaded Integrator-Comb (CIC) Filters, 25.29 to 25.32 Cassegrain antenna, 12.21 to 12.23, 12.25, 14.34 Cassini, 18.46 Cathode pulser, 10.23 Cell-averaging CFAR, 7.11 to 7.12, 7.17 CFAR, 7.11 to 7.18 and ECCM, 24.35 to 24.36 loss, 4.44 probability of detection, 7.15 target suppression in, 7.16 to 7.17 Chaff, 24.5 to 24.6 Chaff and ECCM, 24.19, 24.34 Chart radars, 22.22 to 22.23 Chebyshev filter bank, 2.54 to 2.55 Civil Marine Radar (CMR), 22.33 and aids to navigation (AtoN), 22.25, 22.26 antennas, 22.10 to 22.12 Automatic Identification System (AIS), 22.2, 22.8 integration with, 22.23 to 22.25 cost of, 22.3 detection performance, 22.4 to 22.6 detection and processing, 22.13 to 22.15 display, 22.21 early days of, 22.31 to 22.33 environmental conditions, 22.3 international standards for, 22.7 to 22.10 magnetrons for, 10.16 precipitation and sea clutter, 22.5 racons and, 22.26 radar beacons and, 22.25 radar target enhancers (RTEs), 22.27 RF head (transmitter and receiver), 22.12 to 22.13 search and rescue transponders, 22.27 solid-state, 22.16 to 22.17 target tracking, 22.17 to 22.19 user interface, 22.19 to 22.22
validation testing of, 22.28 to 22.29 vertical lobing in, 22.6 to 22.7 Class of (amplifier) operation, 11.18 to 11.20 Clouds, attenuation in, 19.7 to 19.8 CloudSat, 18.63, 19.39 Clustered-cavity klystron, 10.12 to 10.13 Clutter amplitude characteristics, 2.17 attenuation, in MTI, 2.20 to 2.21 characteristics for MTI, 2.10 to 2.19 exponential model, 2.12 to 2.16 in ground penetrating radar, 21.5, 21.10 maps, 2.83 to 2.87, 6.23, 7.19 models, for ground echo, 16.29 to 16.34 MTI filter design, 2.33 to 2.46 optimum filter design, 2.25 to 2.33 point scatterers, 2.18 to 2.19 in pulse doppler radar, 4.14 to 4.24 reflectivity, 2.17 to 2.18 Clutter-limited detection in pulse doppler, 4.48 Coaxial magnetron, 10.14 to 10.15 Coaxitron, 10.21 Cobra Dane radar, 8.36 Coherent processing, and ECCM, 24.34 to 24.35 Coherent Processing Interval (CPI), 2.7 Coherent on receive, 10.14
I_4
COHO, 6.3, 6.20 Collapsing loss, 7.3 Compact range, 14.32 to 14.33 Complementary pulse compression waveforms, 8.19 Complex envelope representation, 8.38 to 8.39 Computer codes for reflector design, 12.33 to 12.35 Conformal arrays, 13.3 Conical-scan tracking, 9.16 to 9.17 Conopulse, 9.15 Constant false alarm rate. See CFAR Continuous wave (CW) radar, 1.5 Constant Efficiency Amplifier (CEA), 10.21 to 10.22, 10.26 Cooperative target identification, 5.22 to 5.23 CORDIC processor, 25.22 to 25.25 Corner reflector, radar cross section, 14.9 to 14.11 Corporate feed monopulse phased array, 9.14 Co secant-squared antenna, and STC, 2.98 COSMO-SkyMed SAR, 18.12 Costas codes, 8.25 to 8.26 Counter Battery Radar (COBRA), 13.62 Creeping waves, 14.3, 14.5 Critical frequency, in HE OTH, 20.3 Crossed-field amplifier (CFA), 10.3, 10.16 to 10.17 Crossed-field tubes, 10.2 Cross-eye ECM, 24.42 to 24.43 Cross-polarization jamming, 24.43 Cross-polarization tracking, 9.40 to 9.41 Crossrange resolution, 17.1 Cross section. See radar cross section Crosstalk, in tracking, 9.40 to 9.41 Crowbar, in transmitters, 10.24 CryoSat altimeter, 18.42 to 18.43
D D region, 20.14 Dällenbach layer, 14.37 to 14.38 Data link, missile, 5.26 Data links, in MFAR, 5.24 to 5.27 Data processing, 1.3 dBZ, 19.5 to 19.6 DC operation of CFA, 10.17, 10.24 Deceptive ECM (DECM), and ECCM, 24.6 to 24.7, 24.40 and tracking radar, 24.41 to 24.42 Decimation, 6.41 to 6.42 Decimation filters, 25.28 to 25.32 Decoys, 24.6, 24.8 Delta-Sigma converters, 6.36 Depressed collector, 10.10 Detection acceptance, 7.25 to 7.26 Detectors batch processor, 7.8 to 7.11 binary integrator, 7.7 to 7.8, 7.12 to 7.13 M-out-of-N, 7.7 to 7.8 moving window, 7.4 to 7.7 nonparametric, 7.17 to 7.18 optimal, 7.2 to 7.4 practical, 7.4 to 7.11 rank, 7.17 to 7.18 Dicke fix, 24.33, 24.35 Differential reflectivity, 19.18 Diffraction, 26.5 Digital beamforming, 13.8, 13.56 to 13.57 multiple beams, 25.17 to 25.19
Digital downconversion (DDC), 6.41 to 6.42, 6.44 to 6.45, 25.6 to 25.15 Digital filters, 25.26 to 25.32 Digital pulse compression, 25.19 generation of, 8.28 to 8.30 Digital receiver, 6.40 to 6.46 block diagram, 25.2 direct sampling, 25.38 Digital RF memory (DREM), 24.6 to 24.7 Digital signal processing hardware implementation, 25.35 to 25.37 timing dependence, 25.34 to 25.35 tools, 25.22 to 25.34 Digital upconverter (DUC), 25.21 to 25.22 Diode phase shifter, 13.51 to 13.52 Dipole antenna, 21.25 to 21.26 Direct digital downconversion, 25.10 to 25.15 Direct digital synthesizer (DDS), 6.22, 6.48 to 6.49, 25.20 to 25.21 Direct sampling digital receiver. 25.38 Direction finding (DF) and radar, 7.50 to 7.54 Directive gain, of an antenna, 12.5 Discrete Fourier transform (DFT), 25.32 to 25.34 Displaced Phase Center Antenna (DPCA), 3.10 to 3.13, 3.19 to 3.21, 5.2 to 5.3 Distortion, in receiver, 6.6 to 6.7 Doppler ambiguity resolution, 4.33 to 4.34
I_5
Doppler beam sharpening (DBS), 5.34 to 5.36, 5.37, 17.2, 17.3 Doppler, in bistatic radar, 23.14 to 23.17 Doppler filter bank, 2.7 to 2.9 Doppler filter straddle loss, 4.43 Doppler filter weighting loss, 4.43 Doppler radars, 4.1 Doppler scintillation, in tracking radars, 9.36 to 9.37 Doppler shift, 1.10 Doppler spectra, spurious, 6.11 Doppler spectrum of ground echo, 16.16 to 16.19 of HF sea echo, 20.49 to 20.52, 20.75 Doppler weather radar, 1.7 Ducts atmospheric, 26.7 to 26.10 elevated, 26.12 to 26.13 evaporation, 26.11 to 26.12 surface, 26.10 to 26.11 Duplexer, 1.2, 6.2 Dynamic range, 1.3, 6.4 to 6.8 of A/D converters, 6.38 to 6.39 and ECCM, 24.32 to 24.33 in pulse doppler radar, 24.32 to 24.33
E E-2C, 3.3 E-2D, 3.1 to 3.3 E region, 20.14 Early-late gate range tracking, 9.21 to 9.22 Eclipsing loss, 4.40 to 4.43, 5.18 Effective-earth-radius model, 26.15 Eldora radar, 19.37 to 19.38 EM system assessment, 26.18 to 16.23 Electronic Attack, 24.2 Electronic counter-countermeasures (ECCM) antenna-related, 24.10 to 24.31 decoys, 24.8 efficiency, 24.54 to 24.56 and imaging radar, 24.48 to 24.52 and ISAR, 24.51 to 24.52 operational-deployment techniques, 24.36 to 24.37 and over-the-horizon radar, 24.52 to 24.53 and phased array radar, 24.43 to 24.48 and radar equation, 24.55 to 24.56 receiver related, 24.32 to 24.33 role of the operator with, 24.36 SLB and SLC, 24.17 to 24.20 sidelobe canceler, 24.14 to 24.20 signal-processing related, 24.33 to 24.36 STAP, 24.21 to 24.22 and subarrays, 24.25 to 24.29 and surveillance radars, 24.37 to 24.40 and SAR, 24.48 to 24.51 techniques, 24.8 to 24.9, 24.37 to 24.53 terminology, 24.2 and tracking radars, 24.40 to 24.43 transmitter related, 24.31 to 24.32 Electronic countermeasures (ECM), 24.5 to 24.8 Electronic Protection (EP), 24.2 Electronic-scan monopulse, 9.12 to 9.13 Electronic Support (ES), 24.2 Electronic Warfare Support Measures (ESM), 24.2 to 24.5 Elevated ducts, 26.12 to 26.13
Elint, 24.2, 24.3, 24.4 Emission Control (EMCON), 24.37 ENVIS AT, 18.11 Errors in tracking radar external causes of, 9.37 to 9.43 internal sources of, 9.42 to 9.43, 9.47 reduction techniques, 9.46 to 9.47 sources of, 9.26 target caused, 9.26 to 9.37 ERS SAR, 18.8 to 18.9 Evaporation ducts, 26.11 to 26.12 Exponential model of land clutter, 2.12 to 2.16 Extended Interaction Klystron (EIK), 10.11 External noise at HF, 20.43 to 20.45
F F-117 low cross section aircraft, 14.40 to 14.42 F region, 20.14 to 20.15 Fading, 16.12 False-alarm control, 7.11 to 7.19 Far field, 14.4 Far-field criterion, 14.27 to 14.28 Fast Fourier transform (FFT), 25.33 to 25.34 filter bank, 2.55 to 2.56 Fast Time Constant (FTC), in CMR, 22.5 Fast-wave tube, 10.3 Ferrite phase shifters, 13.52 to 13.53 Fighter aircraft missions, 5.10 to 5.16
I_6
Filter-bank design, 2.52 to 2.59 Filter mismatch loss, in MTI, 2.22 to 2.23 Filters, in radar, 6.24 to 6.29 Finite impulse response (FIR) filters, 2.33, 25.26 to 25.28 FM-CW radar, 1.5, 9.20 Focused SAR, 17.2 Foliage-penetration (FOPEN) SAR, 17.33 to 17.34 Fog, attenuation in, 19.12 Forward scatter, in bistatic radar, 23.21 Fourier transform, 8.38 Frank codes, 8.19 to 8.20 Free-space propagation, 26.13 to 26.15 Frequency agility, 1.9, 24.31 Frequency diversity, 1.9, 24.31 Frequency, effect on radar, 1.14 to 1.18 Frequency multipliers, 6.49 to 6.50 Frequency synthesis, 6.21 to 6.22 Front end, of receiver, 6.10 to 6.14
G GaAs PHEMT FET, 11.12 to 11.16 Geometrical optics, 14.20 to 14.21 and ground echo, 16.8 reflector analysis, 12.33 Geometric theory of diffraction, 14.24 to 14.25 Geosat, 18.41 to 18.42 Ghosts, 2.88, 4.33, 14.35 Glint in bistatic radar, 23.20 to 23.21 in tracking radar, 9.30 to 9.35 Global Nearest Neighbor (GNN), 7.39 to 7.40 Graceful degradation, 13.4 Graded absorber, 14.37 Grating lobes, 13.10 to 13.12 Gregorian antenna, 12.21, 12.25 Gregorian system, 14.33 to 14.34 Grid-controlled vacuum tubes, 10.21 to 10.23, 10.25 Grid locking, 7.49 Ground echo available information from, 16.4 bistatic, 16.29 fading of, 16.12 to 16.19 at HF, 20.29 to 20.30 imaging radar interpretation, 16.55 to 16.56 at low grazing angle, 16.52 to 16.55 measurement techniques for, 16.19 to 16.29 in meteorological radar, 19.13 to 19.14 models for scattering coefficient, 16.29 to 16.34 near-grazing angle, 16.52 to 16.55 near-vertical, 16.25 number of independent samples, 16.24 parameters affecting, 16.4 to 16.7 polarimetry, 16.46 to 16.52 scattering coefficient data, 16.35 to 16.46 scattering coefficients from radar images, 16.28 to 16.29 sea ice, 16.44 to 16.46 snow, 16.42 to 16.44 soil moisture, 16.40 to 16.41 speckle, 16.55 theoretical models, 16.7 to 16.12 vegetation, 16.41 Ground moving target indication (GMTI), 5.38 to 5.42, 17.25 Ground moving target thresholding, 5.39 to 5.40
Ground moving target track (GMTT), 5.38 Ground moving target weapon delivery, 5.40 to 5.41 Ground penetrating radar (GPR) antennas, 21.24 to 21.30 applications of, 21.3, 21.35 to 21.40 archeological applications, 21.36 and land mines, 21.37 AT mines, 21.34, 21.39 attenuation with, 21.7 to 21.9 bandwidth, 21.1 characteristics of, 21.4 clutter in, 21.5, 21.10 comparison with optical image, 21.4 depth resolution, 21.11 description of, 21.1 to 21.6 dispersion in, 21.11 earth material properties, 21.18 to 21.19 example of, 21.2 forensic investigations, 21.35 and frequency domain, 21.23 and glacier, 21.37 image processing, 21.30 to 21.35 licensing of, 21.39 to 21.40 modeling of, 21.13 to 21.18 modulation techniques, 21.21 to 21.24
I_7
polarization, 21.10 to 21.11 propagation, 21.6 to 21.13 reflections in, 21.9 to 21.10 resolution, 21.13 road thickness measurement, 21.37 to 21.38 and SAR, 21.13 signal processing, 21.30 to 21.35 soil suitability map, 21.20 from space, 18.59 to 18.62 systems, 21.20 to 21.21 velocity of propagation, 21.11 Ground plane, 14.31 Guard blanking loss, 4.44 Guard channel, in pulse doppler, 4.19 to 4.22 Gyrotrons, 10.3, 10.17 to 10.19, 10.26
H Hail, attenuation in, 19.11 to 19.12 Hail, detection of, 19.31 Height measurement, with InSAR, 17.30 to 17.33 Height measurement, with SAR, 17.27 to 17.33 HF, 1.15 HF over-the-horizon radar. See over-the-horizon radar High-medium PRF, 4.7 High-PRF pulse doppler, 4.7 to 4.8 High-PRF range-while-search, 4.36 High-PRF ranging, in pulse doppler, 4.34 to 4.35 High-resolution radar, 1.5 Hilbert transform, 6.43 to 6.44 HJ-1-C SAR, 18.13 Hot clutter, 24.43 Hybrid models for propagation, 26.16 to 26.17 Hybrid processors, 25.37
I Identification friend or foe (IFF), integration with radar, 7.50 I/Q channels, 6.31 to 6.35 Image-reject mixer, 6.13 Imaging radar ground echo, 16.55 to 16.56 Improvement factor, for AMTI, 3.8 Improvement factor limitations caused by staggering, 2.42 to 2.44 Improvement factor, for MTI, 2.19 to 2.20, 2.23 to 2.25, 6.17 to 6.18 Inductive output tube, 10.22 Infinite impulse response (IIR) filters, 2.33, 25.26 to 25.27 Insets, radar cross section of, 14.11 to 14.12 Instabilities in MTI, 2.65, 2.73 Instability limitations in MTI, 2.72 Instantaneous bandwidth, 6.9 Interclutter visibility in MTI, 2.22 Interacting multiple model (IMM) in ADT, 7.35 to 7.37 Interferometric SAR (InSAR), 17.5, 17.23 to 17.24 target height measurement, 17.30 to 17.33 International Maritime Organization (IMO), 22.1, 22.4, 22.8, 22.27, 22.28, 22.32 Interpolation filters, 25.28 Inverse Cassegrain, 9.25 Inverse SAR (ISAR), 5.23 to 5.24, 5.31 to 5.33, 9.37, 17.5 and ECCM, 24.51 to 24.52 Ionogram, 20.16 to 20.17 Ionosphere, 20.13 to 20.21 Ionospheric models, 20.19 to 20.20 Isodoppler contours in bistatic radar, 23.16
J Jamming, 5.27, 24.5 Jaumann absorber, 14.36 to 14.37 J-ERS SAR, 18.9 Jet-engine modulation, 5.23 JianBing-5 SAR, 18.12 Jindalee OTH radar, 20.3, 20.22 performance model, 20.67 to 20.70 Joint STARS, 13.66 to 13.67, 17.23 to 17.24 JORN OTH, 20.12, 20.19
K K band, 1.17 Kalman filter, 7.28 to 7.35 Klystrode, 10.22 Klystron, 10.5 to 10.8, 10.26 origin of, 10.2 to 10.3
L L band, 1.16 Land clutter. See ground echo Laser radar, 1.18
I_8
Letter-band nomenclature, 1.13 to 1.14 Lewis and Kretschmer codes, 8.20 to 8.22 Limiters, 6.29 to 6.31 Line-type modulator, 10.23 Linear array antenna, 13.11 to 13.13 Linear-beam vacuum tube, 10.3 Linear-beam amplifier, 10.4 to 10.13 Linear FM pulse compression, 8.3 to 8.11 Liquid crystal display, for CMR, 22.19 Lobing, in elevation, 22.6 to 22.7 Local oscillator, 6.14 to 6.22 Low-earth orbit, 18.2 Low grazing-angle clutter measurements, 16.52 to 16.55 Low-noise amplifier, 6.10 Low radar cross section ships 14.42 to 14.43 vehicles, 14.39 to 14.43 Low-sidelobe antenna, 24.10 to 14.11
M Madre HF OTH radar, 20.24 to 20.45 Magellan Venus mapper, 18.48 to 18.52 Magnetron, 10.2, 10.14 to 10.16, 10.26 for civil marine radar, 10.16, 22.12 Main-beam cancellation, 24.33 MAPSAR, 18.14 to 18.15 Marcum Q-function, 24.22 Marine boundary layer, 26.12 Matched filter, 1.3, 6.25, 8.39 to 8.40 loss in pulse doppler, 4.40 Maximal-length sequences, 8.18 Maxwell’s equations, 14.17 Mechanical design of antenna, 12.35 to 12.41 Medium PRF for air-to-air mode, 5.16 to 5.20 Medium PRF for pulse doppler, 4.8 Medium PRF for range while search, 4.37 to 4.38 Medium PRF selection algorithms, 5.18 to 5.20 Metal plate, radar cross section of, 14.8 to 14.9 Meteor trails, and HF OTH radar, 20.38 to 20.40 Meteorological radar airborne, 19.37 to 19.38 attenuation effects, 19.7 to 19.12 calibration, 19.18 to 19.19 design considerations, 19.6 to 19.19 ground clutter effects, 19.13 to 19.14 measurement accuracy, 19.22 to 19.23 microbursts, 19.29 to 19.31 MTI filter design for, 2.46 to 2.51 multiple radars, 19.33 to 19.35 operational applications, 19.25 to 19.33 phased array, 19.35 to 19.37 polarization, 19.18, 19.27 to 19.28, 19.33 precipitation measurement, 19.26 to 19.28 processor implementation. 19.24 to 19.25 pulse compression, 19.23 to 19.24 pulse-pair algorithm, 19.21 range and velocity ambiguities, 19.12 to 19.13 research applications, 19.33 to 19.40 severe storm warning, 19.28 to 19.33 signal processing, 19.19 to 19.25 spaceborne, 19.38 to 19.39 spaced antenna techniques, 19.40 spectrum moment estimation, 19.20 to 19.21
typical designs, 19.14 to 19.18 whitening filter, 19.24 wind profiler, 19.39 to 19.40 Method of moments, 14.1, 14.18 to 14.19 MFAR. See Multifunctional Fighter Aircraft Radar Microbursts, 19.29 to 19.31 Microwaves, 1.1, 1.14 Microwave monolithic integrated circuits (MMIC) characteristics of, 11.24 to 11.29 power amplifiers, 11.26 low-noise amplifiers, 11.26 phase shifters, 11.27 to 11.29 transmit/receive switching, 11.27 Microwave power module (MPM), 10.13 Military radar, 1.20 Millimeter waves, 1.14, 1.17 to 1.18 Mirror-scanned antenna, 9.25 Missile guidance performance assessment, 5.42 Missile-range instrumentation radar, 9.2 Mixer, image-reject, 6.13 Mixers, performance parameters, 6.14 Mixers, spurious response of, 6.11 to 6.13 MMIC. See Microwave monolithic integrated circuits
I_9
Modeling, of propagation, 26.13 to 26.17 Modified generalized sign test processor, 7.17 to 7.19 Modulators, 10.23 to 10.25 Monopulse-antenna feed techniques, 9.6 to 9.10 Monopulse antenna feeds, 12.26 to 12.28 Monopulse, dual band, 9.24 to 9.25 Monopulse, and ECM, 24.23 to 24.24, 24.42 to 24.43 Monopulse, phased arrays, 13.4 Monopulse tracking, 9.3 to 9.16 Moving Target Indication (MTI), 1.5, 4.2 A/D converter effect on dynamic range, 2.78 to 2.80 adaptive, 2.80 to 2.83 binomial weight cancelers, 2.35 and birds as clutter, 2.85, 2.87 to 2.88, 2.96 to 2.98 blind speeds, 2.9 to 2.10 block diagram, 2.4 to 2.7 canonical filter design, 2.34 clutter attenuation (CA), 2.20 to 2.21 clutter characteristics, 2.10 to 2.19 clutter filter-bank design, 2.52 to 2.59 clutter filter response, 2.9 to 2.10 clutter maps, 2.83 to 2.87 clutter visibility factor (Voc), 2.23 definitions, 2.19 to 2.23 dynamic range, 2.78 to 2.80 environmental considerations, 2.94 to 2.100 feedforward canceler, 2.39 filter design, 2.25 to 2.46 filter design for weather radar, 2.46 to 2.51 filter mismatch loss, 2.22 to 2.23 hardware considerations, 2.92 to 2.94 improvement factor, 2.19 to 2.20, 2.23 to 2.25, 6.17 to 6.18 interclutter visibility (ICV), 2.22 limitation due to scanning, 2.23, 2.38 limiting in receiver, 2.59 to 2.65 one-delay canceler, 2.35 optimum clutter filter design, 2.25 to 2.33 performance degradation due to limiting, 2.59 to 2.65 pulse compression considerations, 2.75 to 2.78 purpose of, 2.2 radial velocity ambiguity resolution, 2.89 to 2.91 range ambiguity resolution, 2.89 to 2.91 rules for, 2.92 to 2.94 in SAR, 17.23 and STC, 2.96 to 2.98 sensitivity velocity control (SVC), 2.87 to 2.91, 2.99 to 2.100 signal-to-clutter ratio improvement (ISCR), 2.21 to 2.22 stability requirements, 2.65 to 2.78 staggered PRF design, 2.39 to 2.46 subclutter visibility (SCV), 2.6, 2.22 superclutter visibility, 2.84 three-delay canceler, 2.37 two-delay canceler, 2.36 unwanted targets, removal of, 2.96 to 2.100 Moving targets, in SAR, 17.23 to 17.27 Moving Target Detection (MTD), 2.6 to 2.9 block diagram, 2.6 to 2.7 ducted propagation, effect of, 2.95 Moving-window detector, 7.4 to 7.7 MTBF, of klystrons, 10.6 to 10.7 Multi-beam digital beamforming, 25.17 to 25.19 Multifunction radar, 1.7, 13.1 Multifunctional Fighter Aircraft Radar (MFAR), 5.2 to 5.7 processing, 5.5 range-doppler situation in, 5.7 to 5.8
software structure, 5.6 to 5.7 Multipath, 26.4 to 26.5 in tracking radar, 9.37 to 9.40, 9.46 to 9.47 Multiple-beam klystron, 10.7 to 10.8 Multiple hypothesis algorithm in track association, 7.40 to 7.41 Multiple Object Tracking Radar (MOTR), 9.2, 9.26 Multiple reflector antenna, 12.21 to 12.24 Multiple scattering in target recognition, 14.35 Multiplicative noise, 4.28, 18.18 in SAR, 17.17 to 17.18
N NCAR dual band radar, 19.17 Networked radar, 7.46 to 7.49
I_10
Nexrad (WSR-88D) weather radar, 19.1, 19.16 to 19.17 automated weather products, 19.25 Noise, in receiver, 6.4 to 6.5 Noise, in tracking, 9.27 to 9.30 Noncooperative air target recognition, 5.22 to 5.24 Nonlinear FM pulse compression, 8.12 to 8.16 Nonparametric detectors, 7.17 to 7.18 Nonspecular absorbers, 14.38 nth-time-around tracking, 9.24 Nyquist, 25.2, 25.4 to 25.6
O Ogive, radar cross section of, 14.7 to 14.8 On-axis tracking 9.25 to 9.26 Operating bandwidth, 6.9 Optics region, 14.5 to 14.6 Optimal detection, 7.2 to 7.4 Orographic rain, 19.26 Oscillator vs. amplifier transmitter, 10.4 Ovals of Cassini, 23.6 to 23.8 Over-the-horizon radar antennas for, 20.24 to 20.26, 20.45 to 20.46 calibration, 20.48 to 20.49 clutter, 20.29 to 20.33 coherent processing for, 20.6 compared to microwave radar, 20.7 to 20.10 doppler spectrum of the sea, 20.49 to 20.52 and ECCM, 24.52 to 24.53 examples of, 20.11 to 20.12 external noise in, 20.40 and meteor trails, 20.38 to 20.40 noise models, 20.43 to 20.45 oceanography, 20.33 to 20.38 performance modeling, 20.55 to 20.70 propagation factor, 20.6 to 20.7 radar cross section, 20.26 to 20.29 radar equation, 20.5 to 20.7 receiving system, 20.45 to 20.49 resource management, 20.54 to 20.55 revisit times, 20.4 to 20.5 signal processing, 20.49 to 20.54 sky wave radar design, 20.8 to 20.13 spectrum occupancy, 20.40 to 20.45 surface-wave radar, 20.70 to 20.76 tracking, 20.53 to 20.54 transmitters, 20.23 to 20.26 waveforms, 20.21 to 20.23
P PALSAR, 18.11, 18.15 to 18.16 Parabolic cylinder antenna, 12.18 to 12.19 Parabolic equation methods, for propagation, 26.16 Parabolic reflector antenna, 12.17 to 12.18 Passive bistatic radar, 23.29 Passive ECM, 24.5 to 24.6 Passive listening, 5.34 Patriot radar, 13.66 to 13.67 Pave Paws radar, 11.31 to 11.32 Penetration aids accompanying ballistic missiles, 24.6 Phase-comparison monopulse, 9.11 to 9.12 Phase instabilities, 2.66 to 2.70
Phase noise in pulse doppler, 4.28 to 4.30 Phase shifters, 13.51 to 13.53 Phased array radar active aperture, 13.53 to 13.55 antennas, 13.2 to 13.3 AN/SPY-1, 13.62 AN/SPY-3, 13.69 aperture matching, 13.20 array simulator for, 13.25 to 13.26 bandwidth of, 13.38 to 13.45 beam switching, 13.8 calibration of active arrays, 13.60 to 13.62 circular polarization, 13.6 constrained feed, 13.46 Counter Battery Radar (COBRA), 13.62 digital beamforming, 13.56 to 13.57 diode phase shifters, 13.51 to 13.52 and ECM, 24.43 to 24.48 element pattern, 13.22 to 13.23 errors in, 13.30 to 13.38 feed networks, 13.46 to 13.50 ferrite phase shifters, 13.52 to 13.53 frequency scan, 13.7 to 13.8 gain, 13.13 to 13.15 grating lobes, 13.10 to 13.12, 13.17 to 13.19 ground-based, 13.63 to 13.65 illumination functions, 13.28 to 13.29 instantaneous bandwidth, 13.42 to 13.45 limited scan, 13.6 to 13.7
I_11
linear array, 13.11 to 13.13 low sidelobes, 13.28 to 13.33 meteorological, 19.35 to 19.37 monitoring of, 13.4 to 13.5 monopulse tracking, 9.12 to 9.13, 13.4 multifunction, 13.1 mutual coupling, 13.20 to 13.22 optical feed, 13.46 parallel feed, 13.48 to 13.49 periodic errors in, 13.35 to 13.38 phase-only control, 13.58 phase quantization, 13.34 phase shifters, 13.51 to 13.53 planar array, 13.15 to 13.19 radiation pattern nulling, 13.57 to 13.60 scanning, 13.7 to 13.9 series feed, 13.47 to 13.48 simultaneous receive beams, 13.54 to 13.56 small arrays, 13.27 solid-state modules for, 13.53 to 13.54 solid-state transmitter for, 11.24 to 11.31 subarrays, 13.43 to 13.44, 13.49 to 13.50 surface waves and mutual coupling, 13.24 to 13.45 Taylor illumination, 13.29 thinned arrays, 13.23 to 13.24 3D search, 13.4 theory, 13.9 to 13.15 time-delay networks, 13.44 to 13.45 time-delay scanning, 13.7 tracking with, 7.46 Volume Search Radar (VSR), 13.62 to 13.63 wide bandwidth operation, 13.6 Phase shift in DSP, 25.22 to 25.25 Physical optics, 14.21 to 14.24 and ground echo, 16.9 to 16.10 reflector analysis, 12.31 to 12.33 Physical theory of diffraction, 14.25 to 14.26 Pilotage and CMR, 27.31 Pioneer Venus, 18.44 Planar array, 13.15 to 13.19 Planetary radars, 18.43 to 18.53 atmospheric sounding, 18.62 to 18.63 Cassini, 18.46 Clementine, 18.46 to 18.47 cloud profiling, 18.63 flight systems, 18.43, 18.56 to 18.58 ice exploration, 18.47 to 18.48 ionospheric sounding, 18.62 Magellan, 18.45 to 18.46, 18.48 to 18.52 polarization, 18.52 rainfall measurement, 18.62 scatterometers, 18.53 to 18.58 sounders, 18.59 to 18.63 table of, 18.44 Venera, 18.43 to 18.45 Plasma frequency, 20.2 Platform motion, in AMTI, 3.3 to 3.14 compensation abeam, 3.10 to 3.14 forward direction, 3.21 to 3.23 and scan compensation, 3.18 to 3.21 P(n,k) polyphase codes, 8.22 to 8.24 Point-clutter scatterers, 2.18 to 2.19 Polarimetric SAR, 17.22 Polarization and ground echo, 16.46 to 16.52
in ground penetrating radar, 21.10 to 21.11 in meteorological radar, 19.18 for planetary radar, 18.52 Polarization-twist reflector, 12.23 Polyphase codes, 8.19 to 8.24 Power-aperture product, 10.1 Power supply, for AESA, 5.10 Practical detectors, 7.4 to 7.11 Precipitation measurement, 19.26 to 19.28 Precision velocity update, 5.33 to 5.34 Probabilistic data association, 7.39 to 7.40 Probability of detection, in pulse doppler, 4.46 to 4.48 Probability of false alarm, in pulse doppler, 4.44 to 4.46 Propagation, anomalous, 26.6 to 26.13 Propagation factor, 26.1 Propagation, in free space, 26.13 to 26.15 Propagation loss, 4.40 Propagation modeling, 26.13 to 26.17 Propagation, standard, 26.4 to 26.6 Pseudo coherent radar, 6.20 Pulse chasing in bistatic radar, 23.28 to 23.29 Pulse compression block diagram, 8.1 to 8.2 comparison of various waveforms, 8.27 digital, 25.19 and ECCM, 24.34 to 24.35 examples of, 8.30 to 8.36 factors affecting choice of, 8.26 to 8.27
I_12
Pulse compression (cont.) implementation of, 8.28 to 8.30 linear FM, 8.3 to 8.11 in meteorological radar, 19.23 to 19.24 and MTI, 2.75 to 2.78 nonlinear FM, 8.12 to 8.16 phase coded, 8.16 to 8.24 radar, 1.5 range sidelobes, 6.29 SAW devices for, 8.10 to 8.11 signal analysis definitions, 8.36 to 8.37 stretch, 8.31 to 8.36 time-frequency coded, 8.25 to 8.26 waveforms, 8.2 to 8.26 Pulse doppler antenna, 4.12 to 4.13 applications, 4.2 to 4.3 basic configuration, 4.10 to 4.14 block diagram, 4.11 clutter, 4.14 to 4.24 clutter-limited detection, 4.48 doppler ambiguity resolution, 4.33 to 4.34 dynamic range, 4.24 to 4.27 high-PRF ranging, 4.34 to 4.35 losses in, 4.39 nomenclature, 4.1 to 4.2 probability of detection, 4.46 to 4.48 probability of false alarm, 4.44 to 4.46 range ambiguity resolution, 4.31 to 4.33 range performance, 4.39 to 4.48 search mode, 4.36 to 4.38 spectrum, 4.4 to 4.6 stability requirements, 4.27 to 4.31 timeline definitions, 4.9 to 4.10 track mode, 4.38 to 4.39 Pulse-pair algorithm for meteorological radar, 19.21 Pulse repetition frequency and ambiguities in pulse doppler, 4.6 to 4.10 and doppler, 4.2 to 4.4 for SAR, 17.13 to 17.15 Pyramidal absorber, 14.37 to 14.38
Q Quadraphase codes, 8.24 Quantization noise, affect on MTI, 2.73 to 2.74
R Racons, and CMR, 22.26 to 22.27 Radar applications of, 1.20 to 1.22 bandwidth in, 1.8 to 1.9 basic parts of, 1.2 beacons, in CMR, 22.25 blinking for ECCM, 24.37 block diagram, 1.3 in brief, 1.1 conceptual system design, 1.22 to 1.23 cross section of aircraft, 14.13 to 14.14 approximate methods, 14.19 to 14.27 approximations for simple scatterers, 14.10
basic echo mechanisms, 14.2 to 14.4 of birds, 14.11 bistatic, 23.19 to 23.21 of bodies of revolution, 14.39 to 14.40 characteristics, 14.5 to 14.16 of complex objects, 14.11 to 14.16 of a corner reflector, 14.9 to 14.11 definition of, 14.4 to 14.5 exact methods, 14.16 to 14.19 at HF, 20.26 to 20.29 general, for various target types, 14.16 of insects, 14.11 to 14.12 of a man, 14.11 to 14.12 measurement ranges, 14.30 to 14.35 measurement techniques, 14.27 to 14.35 of a metal plate, 14.8 to 14.9 of an ogive, 14.7 to 14.8 prediction techniques, 14.16 to 14.27 of ships, 14.13 to 14.15 of a short wire dipole, 14.7 of a sphere, 14.5 to 14.6 of string, 14.6, 14.7, 14.29 and surface traveling waves, 14.7 of target support, 14.29 to 14.30 doppler shift in, 1.10 echo suppression, 14.36 to 14.43 in A-12, 14.40 in B-2, 14.42 in F-117, 14.40 to 14.42 in SR-71, 14.39 to 14.41 in X-45C, 14.42 to 14.43 by absorbers, 14.36 to 14.38
I_13
by shaping, 14.36, 14.38 to 14.39 in ships, 14.42 to 14.43 equation, 1.10 to 1.13 bistatic, 23.4 to 23.6 and chaff, 24.55 to 24.56 in conceptual design, 1.23 ground penetrating radar, 21.8 to 21.9 HF over-the-horizon, 20.5 to 20.7 and jamming, 24.55 for meteorological targets, 19.3 to 19.6 surveillance, 3.1 frequency bands, 1.13 to 1.14 hole, in propagation, 26.9 information from, 1.7 to 1.10 letter-band nomenclature, 1.13 to 1.14 multifunction, for fighter aircraft, 5.1 to 5.10 networked, 7.46 to 7.49 nomenclature, 1.18 to 1.19 oceanography at HF, 20.30 to 20.38 past advances in, 1.19 to 1.20 reflectivity, 19.3 reflectivity factor, Z, 19.4 scheduling and control, 7.46 types of, 1.5 to 1.7 warning receiver (RWR), 24.4 to 24.5 work station, 24.55 to 24.56 RADARS AT, 18.9 to 18.10 Radial velocity, 1.7 Radiating elements, 13.5 to 13.6 Radomes, 12.39 to 12.41 Radome loss, 4.40 Rain, attenuation by, 19.8 to 19.11 Rain, detection of, 19.3 to 19.6 RAMP air traffic control radar, 11.33 to 11.34 Range, as used in radar, 1.2, 1.7 Range ambiguities, in meteorological radar, 19.12 to 19.13 ambiguity resolution in pulse doppler, 4.31 to 4.33 and doppler, in MFAR, 5.7 to 5.8 error, in tracking radar, 9.43 to 9.44 filter map in sidelobe blanking, 24.13 to 24.14 -gate pull-off, 24.6, 24.44 -gate straddle loss, 4.40 to 4.43 -gated high PRF (RGHPRF), 5.20 to 5.22 gates, 4.2 gating in pulse doppler, 4.9 glint, 9.35 to 9.36, 9.47 noise, 9.35 to 9.36 sidelobes, 6.29 tracking, 9.21 to 9.24 Rank detector, 7.17 Rapid Doppler on Wheels (Rapid-DOW) 19.36 to 19.37 Ratio detector, 7.13 to 7.14 Rayleigh region, 14.5, 19.3 to 19.4 Rayleigh scattering, 14.19 to 14.20 Ray tracing, 20.20 to 20.21 Receiver, 1.3 analog-to-digital converter, 6.35 to 6.40 bandwidth, 6.9 channel matching, 6.29 COHO, 6.20 configuration of, 6.1 to 6.4 digital, 6.40 to 6.46 diplex operation, 6.46 to 6.47 dynamic range, 6.4 to 6.8
effect on radiated signal, 6.11 exciter, 6.47 filtering, 6.24 to 6.29 front end, 6.10 to 6.14 gain control of, 6.22 to 6.24 instability, 6.20 to 6.21 I/Q channels, 6.31 to 6.35 limiter, 6.29 to 6.31 local oscillator, 6.14 to 6.22 multi-channel, 6.45 to 6.46 noise, 6.4 to 6.5 and tracking accuracy, 9.42 spurious response, 6.11 to 6.12 STALO, 6.14 to 6.20 upconversion, 6.47 to 6.50 waveform generation, 6.47 to 6.50 Receiver-related ECCM, 24.32 to 24.33 Reentrant structures and cross section, 14.3 Reflectivity, 19.3 Reflectivity factor, Z, 19.4 Reflector antenna analysis, 12.31 to 12.35 applications of, 12.1 to 12.2 architecture, 12.16 to 12.25 array feeds for, 12.28 to 12.30 basic principles of, 12.3 to 12.15 environmental factors, 12.39 feed blockage, 12.6 to 12.8
I_14
Reflector antenna (cont.) feed displacement, 12.14 feeds for, 12.25 to 12.30 gain optimization, 12.8 to 12.10 mechanical design, 12.35 to 12.41 radomes for, 12.39 to 12.41 role in radar, 12.1 spillover loss, 12.6 strut blockage, 12.14 to 12.15 surface ace of, 12.10 to 12.14 surface roughness loss, 12.12 to 12.14 types of, 12.2 Refraction, 14.20, 26.3 to 26.4 Refractivity, 26.3 to 26.4 Refractivity measurements, 19.32 to 19.33 Region of uncertainty (ROU) in target tracking, 7.47 to 7.48 Remote sensing of the environment, 1.21 Remote sensing, with SBR, 18.11 Repeater jammer, 24.6 Resolution, in GPR, 21.11 to 21.13 Resonance region, 14.5 RF receive loss, 4.40 RF transmit loss, 4.40 RGHPRF (Range Gated High PRF) algorithm, 5.22 Ricker wavelet, 21.11, 21.21 RIS AT SAR, 18.14 River radar, 22.9 ROTHR, 20.3
S S-193 altimeter, 18.33 S band, 1.16 Salisbury screen, 14.36 Sampled signal spectrum, 25.3 to 25.5 Sampling period in phased arrays, 24.45 Sampling receiver, 21.23 SAR-Lupe radar, 18.13 to 18.14 SARTs (Search and Rescue Transponders), 22.27 SAW delay line for pulse compression, 8.10 to 8.11 Scan compensation, and platform motion, 3.18 to 3.21 Scan SAR, 18.12 to 18.13, 18.24 Scatterer, 14.4 Scatterometers, 16.19 to 16.24, 16.26 to 16.28 space based, 18.53 to 18.58 table of, 18.56 wind measurement, 18.54 to 18.55 Sea clutter Bragg scatter, 15.28 to 15.32, 15.38 breaking waves, 15.6 to 15.7 composite-surf ace model, 15.30 to 15.32 contaminants, effect of, 15.26 to 15.27 and ducting, 15.24 to 15.25 empirical behavior of, 15.7 to 15.27 as a global boundary-value problem, 15.27 to 15.32 at HF, 15.19, 20.30 to 20.33 at high grazing angles, 15.16 at low grazing angles, 15.16 to 15.18 at millimeter waves, 15.20 numerical methods for, 15.36 rain, effect of, 15.23 to 15.24 sea spikes, 15.2, 15.16 to 15.17, 15.35 shadowing, effect of, 15.25 sigma zero definition, 15.7
spectrum, 15.20 to 15.23 statistics, 15.8 to 15.9 surface currents, effect of, 15.25 to 15.26 surface features, 15.33 to 15.34 theories of, 15.27 to 15.37 wind speed and direction, 15.12 to 15.16 Sea descriptors, general, 15.5 to 15.6 Sea echo. See sea clutter Sea ice, 16.44 to 16.46, 16.48, 22.14 Sea spikes, 15.2, 15.16 to 15.17, 15.35 Sea state, 15.6, 22.14 Sea surface, 15.3 Sea surface search, 5.30 to 5.31 Seawinds scatterometer, 18.58 Sensitivity time control (STC), 2.96 to 2.98, 6.22 to 6.24, 19.6 in CMR, 22.5, 22.13 and cosecant-squared antenna, 2.98 in pulse doppler, 4.22 Sensitivity velocity control (SVC), 2.87 to 2.91, 2.99 to 2.100 Sensor integration, other than radar, 7.49 to 7.54 Senrad broadband radar, 24.31 Sequential lobing, 9.16 to 9.17 Servosystems, for tracking radar, 9.17 to 9.19 Shaped pulses for transmitter, 10.19 to 10.20 Shaped reflector antennas, 12.19 to 12.20
I_15
Shaping, for radar cross-section reduction, 14.38 to 14.39 Ship, radar cross section, 14.13 to 14.15 Ships, low cross section, 14.42 to 14.43 Sidelooking airborne radar (SLAR), 1.6 17.3 Sidelobe blanking (SLB), 24.11 to 24.14 Sidelobe canceler, 24.14 to 24.20 Sigma zero (for clutter echo), 15.7, 16.1 to 16.3 Signal-to-clutter ratio improvement, 2.21 to 2.22 Signal-to-noise ratio, 1.9 in SAR, 17.16 to 17.17 Signal processing, and ECCM, 24.33 to 24.36 Signal processing, for meteorological radar, 19.19 to 19.25 Signal processor, 1.3 Signal sampling, 25.15 to 25.16 Silicon bipolar junction transistor, 11.10 to 11.11 Silicon LDMOS FET, 11.11 to 11.12 Silicon transistor capabilities, 11.13 Simultaneous lobing, 9.3 SIR-C, 16.46 SIR (spaceborne) SARs, 18.8 Skin depth, 21.8 Skip zone, 20.3 Sky wave OTH radar, 20.8 to 20.13 Slip-SAR, 18.14 Slow-wave tubes, 10.3 Sniff (or passive listening), 5.34 Snow, echo from, 16.42 to 16.44 Software structure, in MFAR, 5.6 to 5.7 Soil, dielectric properties of, 21.19 Soil moisture, effect on radar echo, 16.38, 16.40 to 16.41 Solar calibration of radar, 19.19 SOLAS (Safety of Life at Sea), 22.8 Solid-state advantages of, 11.1 to 11.5 amplifier, 10.4, 10.26 to 10.28 amplitude and phase sensitivities, 11.22 to 11.23 AN/SPS-40 transmitter, 11.32 to 11.33 class of (amplifier) operation, 11.18 to 11.20 devices, 11.5 to 11.17 examples of, 11.31 to 11.34 MMIC, 11.24 to 11.29 modulator, 11.24 to 11.25 modules, 13.53 to 13.54 Pave Paws radar, 11.31 to 11.32 performance capability, 11.2 phased array transmitter, 11.24 to 11.31 power combining, 11.20 to 11.22 power limitations, 11.8 to 11.10 RAMP radar, 11.33 to 11.34 spectral emissions, 11.23 transmit/receive modules, 11.29 to 11.31 Sounders, 18.59 to 18.63 Space-based radars (SBR) altimeters, 18.29 to 18.43 block diagram, 18.40 CryoSat, 18.42 to 18.43 flight systems, 18.33 to 18.37 Geosat, 18.41 to 18.42 orbit considerations, 18.37 to 18.38 overview, 18.30 to 18.31 precision, 18.31 theoretical foundations, 18.38 to 18.41 hardware, 18.4 to 18.5 meteorological, 19.38 to 19.39 planetary. See planetary radars
synthetic aperture radars (SAR), 18.5 to 18.29 ambiguities, 18.17 to 18.18 ambiguity limits, 18.22 to 18.24 antennas, 18.19 applications, 18.29 data products, 18.21 to 18.22 data rate, 18.20 design issues, 18.16 to 18.24 interferometry, 18.24 to 18.27 Kosmos, 18.8 list of, 18.6 to 18.7 multiple channels, 18.24 to 18.29 nadir, return from, 18.18 orbit characteristics, 18.2 to 18.4 polarimetry, 18.27 to 18.29 PRF constraints, 18.16 to 18.17 processing, 18.20 to 18.21 Quill (first space-based SAR), 18.6 ScanSAR, 18.12 to 18.13, 18.24 Seasat, 18.7 to 18.8 Shuttle Imaging Radar (SIR), 18.8 spotSAR 18.23 strip map, 18.23 transmitters, 18.19
I_16
Space-time adaptive processing (STAP), 3.23 to 3.31, 3.33, 5.2 to 5.3, 5.17, 24.21 to 24.22 in HF OTH radar, 20.53, 24.52 Spark-gap transmitter, 10.2 SPASUR, 23.2, 23.9, 23.11 to 23.13 Speckle, 16.55 Spectral characteristics of clutter, 2.11 to 2.16 Spectral noise in doppler radars, 10.20 to 10.21 Spectrometers, 16.20, 16.26 to 16.28 Spectrum, of pulse doppler radar, 4.4 to 4.6 Specular point, 14.20 to 14.21 Specular scatterers, 14.3 Sphere, radar cross section of, 14.5 to 14.6 Spherical reflector antenna, 12.24 to 12.25 Spotlight SAR, 17.4 to 17.5 SpotSAR, 18.12, 18.23 Spread-F region, 20.19 Spurious output, in transmitters, 10.19 Spurious response of mixers, 6.11 to 6.13 SR-71 low cross section aircraft, 14.39 to 14.41 Stability requirements in pulse doppler, 4.27 to 4.31 Stagger PRF design for MTI, 2.39 to 2.46 STALO, 6.3, 6.14 to 6.20 Standard atmosphere, 26.3 Stand-off jamming (SOJ), 24.43 to 24.44 Station keeping, airborne, 5.27 Stealth, 14.2, 14.36, 24.38 Stratiform rain, 19.26 Stretch pulse compression, 6.10, 6.22, 8.31 to 8.36 in SBR altimeter, 18.40 to 18.41 String, radar cross section of, 14.6 to 14.7 Strip map, 18.23 Stripmap SAR (or “strip” SAR), 17.3 to 17.4 Subarray adaptivity to ECM, 24.25 to 24.27 Subarrays, 13.43 to 13.44, 13.49 to 13.50 Subclutter visibility, in MTI, 2.22 Subrefraction, 26.6 Sudden ionospheric disturbance, 20.18 Sunspot number, 20.17 Superclutter visibility, 2.84 Superheterodyne, 6.1 Superrefraction, 26.7 Superresolution, 24.30 to 24.31 Surface discontinuities, and radar cross section, 14.3 Surface ducts, 26.10 to 26.11 Surface traveling-wave echoes, 14.36, 14.38 Surface ace-wave absorbers, 14.38 Surface winds, and HF radar, 20.37 to 20.38 Surveillance radar, 1.5 Surveillance radar equation, 1.12 Synthesizer, digital, 25.20 to 25.22 Synthetic aperture radar (SAR) autofocus, 17.15 basic principle of 17.1 burst mode, 18.23 to 18.24 clutterlock, 17.15 comparison with optical imaging, 17.18 to 17.21 comparison with real-aperture radar, 17.9 to 17.10 crossrange resolution, 17.7 to 17.8 design issues for SBR, 18.16 to 18.24 doppler beam sharpening, 5.34 to 5.36, 5.37, 17.2, 17.3 early history of, 17.2 and ECCM, 24.48 to 24.51 fast-time processing, 17.6 focused, 17.3 to 17.5 foliage penetration, 17.33 to 17.34
and ground penetrating radar, 21.4, 21.13 height measurement with, 17.27 to 17.23 image quality, 17.16 to 17.21 interferometric (InSAR), 17.5, 17.23 to 17.24, 17.30 to 17.33 inverse (ISAR), 5.23 to 5.24, 5.31 to 5.33, 9.37, 17.5, 24.51 to 24.52 Joint STARS, 17.23 to 17.24 key aspects of, 17.10 to 17.15 key equations, 17.21 to 17.22 motion compensation in, 17.12 moving targets in, 17.23 to 17.27 multiplicative noise ratio, 17.17 to 17.18 point-spread function, 17.16 polarimetric, 17.22 pulse repetition frequency requirements for, 17.13 to 17.15 range migration, 17.15 range resolution, 17.6 to 17.7 range and velocity contours, 17.10 to 17.12
I_17
resolution, 17.5 to 17.10 resolution (crossrange) examples, 17.5 to 17.6 shadows in, 17.28 signal-to-noise ratio, 17.16 to 17.17 slow-time processing, 17.6 for space applications, 18.5 to 18.29 specific aspects of, 17.22 to 17.34 spotlight, 17.4 to 17.5 squinted stripmap, 17.4 stereo, 17.29 to 17.30 stripmap, 17.3 to 17.4, 17.14 to 17.15 types of, 17.2 to 17.6 vibrating targets in, 17.25 to 17.27 unfocused, 17.3 Washington monument image, 17.18 to 17.21 System instabilities and MTI, 2.65 to 2.73 System noise, 6.5
T TACCAR, 3.4 to 3.9, 3.33 Target acquisition, in tracking radar, 9.20 to 9.21 Target caused errors in tracking, 9.26 to 9.37 Target cross section. See radar cross section Target noise, in tracking radar, 9.26 to 9.37 Target recognition, 1.7 cooperative, 5.22 to 5.23 noncooperative 5.22 to 5.24 Target resolution, in automatic detection, 7.19 to 7.20 Taylor weighting or illumination, 8.7 to 8.9, 13.29 TecSAR, 18.12 TEM horn, 21.27 to 21.30 Terminal Doppler Weather Radar (TDWR), 19.1, 19.30 to 19.31 MTI filter design for, 2.47 to 2.50 Terrain avoidance, 5.28 to 5.29 Terrain-bounce jamming, 24.43 Terrain database and radar, 5.30 Terrain following, 5.28 to 5.29 Terrain height estimation, 5.29 to 5.30 Terrain scattered interference, 24.43 TerraS AR-X, 18.12 Test ranges, indoor, 14.32 to 14.35 Test ranges, outdoor, 14.30 to 14.32 THAAD radar, 13.68 Thunderstorm prediction, 19.32 Time-delay scanning, 13.7 Time-frequency coded waveforms, 8.25 to 8.26 Topex altimeter parameters, 18.35 Tornado detection, 19.28 to 19.29 Towed decoy, 24.8 T/R module, 10.28 Track association, 7.38 to 7.41 Track file, 7.23 to 7.25 Tracking, automatic, 7.22 to 7.46 Tracking radar, 1.6 acquisition with, 9.20 to 9.21 automatic gain control (AGC), 9.33 to 9.35 conical scan, 9.16 to 9.17 dual band, 9.24 to 9.25 and ECCM, 24.43 error reduction techniques, 9.46 to 9.47 errors in, 9.26 to 9.46 external causes of error, 9.37 to 9.42 glint in, 9.30 to 9.35, 9.47
limitations in performance, 9.44 to 9.45 monopulse, 9.3 to 9.16 two-channel, 9.14 to 9.15 multipath error reduction, 9.46 to 9.47 nth-time-around tracking, 9.24 on-axis tracking, 9.25 to 9.26 range tracking in, 9.21 to 9.24 sequential lobing, 9.16 to 9.17 servosystems for, 9.17 to 9.19 sources of error in, 9.26 updating tracks, 7.26 to 7.30 TRAKX, dual band monopulse radar, 9.24 Transmit/receive module characteristics, 11.29 to 11.31 Transmit signal digital processing, 25.20 to 25.22 Transmitter-related ECCM, 24.31 to 23.32 Transmitters, 1.2, 1.4 clustered-cavity klystrons, 10.12 to 10.13 constant efficiency amplifier, 10.21 to 10.22, 10.26 crossed-field amplifiers (CFA), 10.16 to 10.17 extended interaction klystron (EIK), 10.11 grid-controlled tubes, 10.21 to 10.23, 10.25 gyrotrons, 10.17 to 10.19, 10.26 for HF OTH radar, 20.23 to 20.26 linear-beam amplifiers, 10.4 to 10.13
I_18
Transmitters (cont.) klystrons, 10.5 to 10.8, 10.26 multiple-beam, 10.7 to 10.8 magnetrons, 10.14 to 10.16, 10.26 microwave power module (MPM), 10.13 modulators for, 10.23 to 10.24 MTBF of tubes, 10.6 to 10.7, 10.10, 10.15, 10.16 oscillator vs. amplifier, 10.4 role in radar, 10.1 to 10.2 solid-state, 10.26 to 10.28. See also solid-state spectrum control, 10.19 to 10.21 traveling wave tube, 10.3, 10.8 to 10.10, 10.26 Twystron, 10.11 types of, 10.2 to 10.4 variants of klystrons and TWTs, 10.11 to 10.13 which type to use, 10.25 to 10.28 Transponder, 24.6 Trapping, in ducting, 26.7 Tropical Rainfall Measurement Mission (TRMM) SBR, 18.62, 19.39 Troposphere, 26.2 effect on tracking accuracy, 9.41 to 9.42
U UHF, 1.15 Ultralow sidelobes, 24.37 Ultrawideband (UWB), 21.1 Updating tracks, 7.26 to 7.30
V Velocity ambiguities, in meteorological radar, 19.12 to 19.13 Velocity-Azimuth-Display (VAD), 19.31 to 19.32 Velocity estimation, 19.22 Velocity of propagation, in GPR, 21.11 Velocity search, in pulse doppler, 4.36 Venera, 18.43 to 18.45 Vessel tracking service (VTS) radars, 22.1 Vessel tracking services, 22.29 to 22.31 VHF, 1.15 Vibrating targets, in SAR, 17.25 to 17.27 Volume Search Radar (VSR), 13.62 to 13.63
W Wake detection, 5.31 Warloc millimeter-weave radar, 10.18 Washington Monument SAR image, 17.18 to 17.21 Water vapor, attenuation in, 19.7 Water vapor measurement with radar, 19.32 to 19.33 Wave spectrum, of the ocean, 15.3 to 15.5 Waveform upconversion, 6.50 Waveguide models, for propagation, 26.15 to 26.26 Weather avoidance, with fighter radar, 5.24 Weather radar. See meteorological radar Wedgetail AEW radar, 3.3 Wide bandgap semiconductors, 11.15 to 11.17 Wind measurement, 19.31 to 19.32 Wind profiler, 19.39 to 19.40 WSR-88D (Nexrad), 19.1, 19.16 to 19.17
X X-45C low cross section unmanned combat aircraft, 14.42 to 14.43 X band, 1.17 X-Band Radar (XBR), 13.68 to 13.69
Z Z (radar reflectivity factor), 19.4 Ze (effective reflectivity factor), 19.6