Table Of Content( Oc,
NAVIGATION f<
Edited by
JOHN S. HALL, PH.D.
ASSOCIATE PFIOFESSOEI OF ASTRONOhfY AND PHYSICS
AMHF.FIST CO1.l,EGE
OFFICE OF SCIENTIFIC RESEARCH AND DEVELOPMENT
N.kTIONAL D13F131vSE RESE.iRCH COMIIITTEE
FmsT EDITION
NEW YORK AND I.ONDOIV
kflcGRAw -HILL BOOK COMPANY, INC
1947
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R.41).+R .UI)S T(3 XAVIGA’IYON
COpyRIGFtT, 1!)47, B~-THE
\IrCJRIW-HILL BOOK CnMP.\xI-. INC.
PRINTEI) IX THE UNITED SrI~.4TES OF .kMliRICA
.111lights resewed Y’his book. or
Paris thereof, m ynot bcreproduced
in on!i form 7uithtI;[(pennissim of
the publishers.
THE MAPLE PRESS COMPANY, YORK, PA.
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MASSACHUSETTS INSTITUTE OF TECHNOLOGY
RADIATION LABORATORY SERIES
BoardofEditors
LouIs N. RIDENOUBE,ditor-in-Chief
GEORGE B. COLLINS, Deputy Editor-in-Chief
BEITTONCHANCES,.A.GOUDSMIRT.,G.HERB,HUBEETM.JAMESJ,ULIANK.KNIPP
JAMESL. LAWSON, LEON B. LINFORD, CAROL G. MONTGOMERCY.,NEWTONA,LBEIW
M. STONEL,ouIs A. TURNERG, EORGEE. VALLEY,JR.,HERBERT H. WHEATON
1. RADAR SYSTEMENGINEERING—Ridenour
2. RADAR AIDS TONAVIGATION—HU21
3. RADAR BEAcoNs—Roberls
4. LoRAN—Pierce, McKenzie, and Woodward
5. PULSE GENERATORS-6%S0e and Lehacqz
6. MICROWAVE MAGNETRONS—CO/~~nS
7. KLYSTRONS AND MICROWAVE TR1oDEs—Hamillon, Knipp, and Kuper
8. PRINCIPLES OF MICROWAVE (%icuITs—Monigo?nefg, Dicke, and Purcell
9. MICROWAVE TRANSMISSION CIRCUITS—hkgan
10. WAVEGUIDE HANDBooK—Mamwilz
11. TECHNIQUE OFMICROWAVE MEAsURE~ENTS—Mon@0mt7~
12. MICROWAVE ANTENNA THEORY ANDDEsIGN—Sike?’
13. PROPAGATION OFSHORTRADIO WAvES—Kt?m’
14. MICROWAVE DUPLEXERS—S~U~/in and Montgomery
15. CRYSTAL RECTIFIERS—~0f7e~ and Whitmer
16. MICROWAVE MIXERs-.?ounU
17. COMPONENTSHANDEooK—BLackhurn
18. VACUUM TUBE AMPLIFIERS— Valle~ and Wallman
19. WAVEFORMS—ChUn03, Hughes, ,lfac.Vichol, i+zyre, and wdliam&
20. ELECTRONIC TIME MEASUREMENTS—Chan@ Hulsizer, MacNachoL,
and Williams
21. ELECTRONIClNsTRuMENTs+Teenuood, Holdam, and MacRae
22, CATHODERAYTUBE DISPLAYS—~o~kr, slaw, and Valley
23. MICROWAVE RECEIVERS—Van Voorhis
24 THRESHOLD&GNAI,s—Lawson and Uhlenheck
25 THEORY OFSERVOMECHANISMS—Ja771.3SN,ichols, and Phillips
26 RADAR SCANNERSANDRAuoMEs—Cady, Karelifz, and Turner
27 COMFLITINGMECHANISMSANDLINitAGES-&JObOd@
28 IrwEx–Henne~
o
Foreword
THEtremendous research and development effort that went into the
development of radar and related techniques during World War II
resulted not only in hundreds of radar sets for military (and some for
possible peacetime) use but also in a great body of information and new
techniques in the electronics and high-frequency fields. Because this
basic material may be of great value to science and engineering, it seemed
most important to publish it as soon as security permitted.
The Radiation Laboratory of MIT, which operated under the super-
vision of the National Defense Research Committee, undertook the great
taskofpreparing these volumes. The work described herein, however, is
the collective result of work done at many laboratories, Army, Navy,
university, and industrial, both in this country and in England, Canada,
and other Dominions.
The Radiation Laboratory, once its proposals were approved and
finances provided by the Office of Scientific Research and Development,
chose Louis N. Ridenour as Editor-in-Chief to lead and direct the entire
project. An editorial staff was then selected of those best qualified for
thistype oftask. Finally the authors for thevarious volumes orchapters
or sections were chosen from among those experts who were intimately
familiar with the various fields, and who were able and willing to write
the summaries of them. This entire staff agreed to remain at work at
MIT for six months or more after the work of the Radiation Laboratory
wascomplete. These volumes stand as a monument to this group.
These volumes serve as a memorial to the unnamed hundreds and
thousands of other scientists, engineers, and others who actually carried
on the research, development, and engineering work the results of which
arehereindescribed. There weresomany involved inthis work and they
workedso closely together even though often in widely separated labora-
toriesthat itisimpossible to name oreven to know those who contributed
toaparticular idea ordevelopment. Only certain ones who wrote reports
orarticles have even been mentioned. But to all those who contributed
inany way to this great cooperative development enterprise, both in this
country and in England, these volumes are dedicated.
L. A. DUBRInGE
RADAR AIDS TO NAVIGATION
EDITORIAL STAFF
L. A. TURNER, TECH. ED.
J. S. HALL, ED.
R. M, WHITMER, ASS’T. ED.
CONTRIBUTING AUTHORS
H. B. ABAJIAN D. B. MCLAUGHLIN
F. R. BANKS, JR. R. E. MEAGHER
J. H. BUCK E. E. MILLER
W. M. CADY R. H. MULLER
M. A. CHAFFEE J. P. NASH
G. C. COMSTOCK C. F. J. OVERHAGE
D. DAVIDSON J. A. PIERCE
R. M. EMBERSON J. B. PLATT
A. G. EMSLIE R. M. ROBERTSON
H. FAHNESTOCK,JR. E. L. SINSHEIMER
G. A. GARRETT C. A. SMITH
D. L. HAGLER H. P. STABLER
J. S. HALL J. M. STURTEVANT
D. HALLIDAY W. J. TULL
J. J. HIBBERT L. A. TURNER
N. W. MACLEAN T. H. WATERMAN
R. M. WHITMER
)v
*
1
Preface
Radar Aids toNavigation isintended primarily to describe the advan-
tages and limitations of radar equipment when applied to problems of
navigation and pilotage, whether the equipment is airborne, shipborne,
orground-based. Radar beacons asaidsto navigation arealsodismmed.
While the development of radar was proceeding apace under the
impetus of the Second World War, the development of ahost of nonradar
navigational aids was also accelerated. These aids include systems that
measurerange differences like Loran and Gee and a number of azimuthal
systems like the German Sonne. Descriptions of these and other non-
radar aids are included to give the reader a more comprehensive picture
of available techniques.
The authors have not always found it possible to present this informa-
tion in a nontechnical form. The reader with no technical background
should obtain a fair estimate of the value of radar in navigational prob-
lemsfrom Chaps. 2,3, 8, and 9. Radar indicators are described in some
detail in this volume because, of all the components, they are of greatest
interest to the navigator. A more detailed discussion of many of the
engineering problems mentioned here is given in Radar System Engi-
neering, Vol. 1 of this series.
In thk volume, the emphasis is placed more on what can now be
done with radar than on what should be possible in the future. A pos-
sible exception to this policy is the inclusion of several photographs of
airborne radar indicators attached to radars with antenna beams 0.8°
wide. Although these pictures illustrate what can now be done, beam-
widths of 3° to 5°, rather than 0.8°, appear practical for airborne radars
to be used as navigational aids in the near future. More emphasis
has been placed on airborne radar used with beacons as an anticollision
device on overwater flights simply because it does not appear reasonable
to require that all airplanes flying over land have beacons.
A real effort has been made to define terms either explicitly or by
their use. A certain amount of repetition results from this policy. For
most radar applications described here, narrow antenna beams neces-
sitating short wavelengths, or microwaves, are commonly prescribed. By
J
PREFACE
thk term is meant radio waves between 1 and 12 cm long. It is not
our intention to insult the reader’s intelligence by defining words found
in a small dictionary, nor even the word radar. There is no glossary.
The definitions of many words may be found by reference to the index.
Thirty-three authors and many persons serving in other capacities
have contributed to this book. Unfortunately it is not practical to give
full acknowledgement to everyone. R, A. Whitmer, assistant editor,
did a large share of the editorial work connected with the portion of the
book devoted to airborne radar. L. A. Turner, technical editor, was
amost constructive influence in clarifying many sections. His criticisms
and suggestions were invariably followed. R. G. Herb served as
technical editor during the formative stage of this project.
David Davidson deserves a solid vote of thanks for selecting the
illustrations used inthe sections onLoran and other navigational nets and
for writing their captions. We are grateful also to M. G. White,
D. T. Griggs, and R. J. Dippy for their criticism. We regretted to learn
that illness prevented Dippy, the originator of Gee, from sending us a
description of the miniature system similar to Gee that the British have
recently used successfully as an airport approach system. Thanks are
due to L. J. Laslett, R. M. Emberson, G. C. Comstock, M. A. Chaffee,
and J. H. Buck for assistance in making the original outlines of the book.
We are grateful to Beka Doherty who, as an uninhibited reader, read the
final manuscript and made many helpful criticisms and suggestions.
We acknowledge with thanks the careful manner in which Louise
Butler, our production assistant, guided the diagrams and photographs
to their ultimate completion. A large amount of secretarial work con-
nected with the book was cheerfully done by Bernyce Goldberg. Thanks
aredue to Eleanor Uhl who acted as editorial assistant during the forma-
tive stages of the book and particularly to Barbara Rudolph who bravely
shouldered this responsibility during its critical final stages.
JOHN S. HALL.
CAMERIDGME,ASS.,
June,1946.
r
Contents
FOREWORD BYL. A. DUBRIDGE . . . vii
PREFACE . . . . . . . . . . . . . . .,, . . . . . . . . . . . . ..ix
PART I. INTRODUCTION
CHAP.1. PRINCIPLES OF RADAR... . . . . . 3
HOWRADARWORKS, ..,... . . . . . . . . . . . ..3
1.1. The Fundamental Ideas. . . . . . 3
1.2. Resolution, Accuracy, and Coverage. . . . . . 10
1.3. Design Considerations. . . . . . . 15
PROPAGATION. . . . . . . . . . . . . . . . . ..21
1.4. Curvature of the Earth and Atmospheric Refraction, . . 21
1.5. Atmospheric Attenuation . . . . . . . . 22
INDICATORS. . . . . . . . . . . . . . . . . . . . . ..26
1.6. Cathode-ray Tubes .,.,, . . . . . . . . . . . . ...26
1.7. Synchros, Servomechanisms, and Amplidynes. 28
1.8. Different Types of Indicators. . . . 30
RADARBEACONS.....,,, . . . . . . . . . ,,36
1.9. Operation...,,,,. . . . . . . . .36
1.10. Future Developments; Systems. 41
CHAP.2. NONRADAR NAVIGATIONAL METHODS . . 44
2.1, Nonradar Navigational ~Methods . . 44
2,2. Radio Ranges .,...,, . . . . . . . . . . . . ...44
2.3. German Radio Rangej Sonne, 47
2.4. Ultri+hlgh-frequency, Navigational Aids, uhf. . 50
2.5. Airborne and Shipborne Direction Finders . 51
2.6, Ground Direction Finders . . . . . . . 54
2.7. Celestial Navigation. . . . , 55
LOEANmn OTHERNAVIGATIONAL NETS . . . . . . . . . . 56
2.8. Hyperbolic Systems . . . . . . . . . . . . . . . 56
2.9. Gee. . . . . . . . . . . . . . . . . . . . . . . . ...60
210.Loral . . . . . . . . . . . . . . . . . . . . . . . ...64
2.11. ’’SLoranr,n .,..,,., . . . . . . . . . . . . ...70
2.12. Low-frequency Loran..., . . . . . . . . . . . . . . . 72
2.13. Mecca. . . . . . . . . . . . . . . . . . . . . . . ...76
CONTENTS
2.14. AccuracyandRangeofVariousHyperbolicSyeteme.. . . . . 77
2.15. Autimatic Data ~alysis .-‘. . . . . . . . . . 79
2.16. Automatic Piloting . . . . . . . . . . . . . . . . . . 82
PART 11. AIRBORNE RADAR
CHAP. 3. CHARACTERISTICS OFAIRBORNE RADAR. . . . . . . . . 89
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
3.1. FeaturesRevealedby RadarMapping. . . . . . . . . . . 89
3.2. DetailsinRadarMapping. . . . . . . . . . . . 96
3.3. TbeOperator. . . . . . . . . . . . . . . . . . . . . . . 105
3.4. MeasurementofDriftandGround%eed . . . . . . . . 105
3.5. Determination of Drift and “Ground Speed”GverWater. . . 110
3.6. InfotrnationAvailableonFlightsOverWater. . . . . . . . 112
3.7. TbeUseofMapaseAidstoRadarPilotage. . . . . . 115
3.8. RadarBeaconNavigation . . . . . . . . . . . . . . . 117
(%AP. 4. SPECIAL AIDS AND DEVICES. . . . . . . . . . . . . . . . 122
NAVIGATIONArm ANTICOLLISION . . . . . . . . . . . . . . . . . . 122
4.1. The Ground Position Indicator. . . . . . . . . . . . . . . 122
4.2. AnticolliAon Radar Devices . . . . . . . . . . . . . . . . 128
Armrrmm DETERMINATION. . . . ,.. . . . . . . . . . . . 131
4.3. Pulsed Radio Altimeters (SCR718C) . . . . . . . . . . . 132
4.4. Frequency-modulated Altimeters (AN/APN-1)’. . . . . . . . 136
4.5. Comparison of F-m and Pulsed Altimeters. . . . . . . . . . 141
4.6. Suggested Future Trends. . . . . . . . . . . 142
CMP. 5. SPECIAL DESIGN CONSIDERATIONS. . . . . . . . . . . 143
5.1. Receivere . . . . . . . . . . . . . . . . . . . . . ...143
5.2. Indicatore . . . . . . . . . . . . . . . . . . . . . ...148
5.3. Antennaa . . . . . . . . . . . . . . . . . . . . . ...155
6.4. Antenna Stabilization . . . . . . . . . . . . . . . . ...156
CHAP. 6. ENGINEERING AND ECONOMIC CONSIDERATIONS. . . . 161
6.1. Installation . . . . . . . . . . . . . . . . . . . . . ...161
6.2. General Design Considerations . . . . . . . . . . . . 165
6.3. Performance of AN/APS-10. . . . . . . . . . . . . 171
6.4. Characteristics of the AN/APS-10 Radar:I . . . . . . . . . 174
6.5. CharacteristicsoftheAN/AP~10 Radar:II. . . . . . . . . 181
6.6. TypicalPerformanceofSomeExistingSystems. . . . . . . 185
6.7. EconomicAspectsofAirborneRadar . . . . . . . 187
PART III. GROUND-BASED RADAR
CHAP.7. TYPES OF GROUND-BASED RADAR AND SPECIAL EQUIP-
MENT . . . . . . . . . . . . . . . . . . . . . . . . ...193
SEARCH mm AUTOMATIC-TRACKKNCJRADARS. . . . 193
7.1. A Long-range Microwave System. . 193
7.2. Automatic Tracking Systems. . 202
CONTENTS
HEIGHTFINDERS, ,,, . . . . . . . . . . . . . . . . . . . . 207
7.3. Height-finding Methods . . . . . . . . 207
7.4. General Problems of Design . . . . . . . . . 212
7.5. Illustrations of Some Recent Systems . . . . . . . . 218
RADAEAIDS FORLANDING . . . . . . . . . . . . . . . . . . . 227
7.6. Beam Approach Systems. . . . . 227
7.7. Beacon Approach Systems, BABS . . . . 232
7+3. Ground-based Scanning Radar Systems . . . . . 237
SPECIALRADLRALDS . . . . . . . . . . . . . . . . . . . . 252
7.9. Moving Target Indication . . 252
7.10. Beacons . . . . . . . . . . . . . . . . . . . . . . ...256
7.11. Radar Relay . . . . . . . . . . . . . . . . . . . . ...258
7.12. Video Mapping . . . . . . . . . . . . . . . . . . . ...267
7.13. Radar Aids to Mapping . . . . . . . . . . . . . . . ...278
@P. 8. RADAR AIDS TO AIR NAVIGATION AND TRAFFIC CONTROL 285
81. Statement of the Problem 285
8.2. Navigation and Traffic Control Using Airborne Radar Aids 293
8.3. Navigation and Traffic Control Using Ground-based Radar Aids 299
&4. Sum~ary of Proposed Aids. ~. . . 311
PART IV. SHIPBORNE RADAR
CnAP.9, NAVIGATIONAND PILOTAGE 317
9.1. How Radar Can Help the Navigator 317
9.2. Coordination of Radar Data with Other Data 320
9.3. Marine Radar Beacons. .322
9.4. Corner Reflectors . . . . . . . . . . . .324
9.5. Principle of Superposition h’avigation . 331
9.6. Char&matching Equipment . 335
9.7. Accuracy Obtainable by Chart Matching. . . . . 344
9.8. PPISlmulations, ,., . . . . . . . . . . . . . . ...351
BIBLIOGRAPHY. . . . . . . . . . . . . . . . . . . . . 353
Crop. 10. A SHIPBORNE NAVIGATIONAL RADAR . . . 354
10.1.Radar Propagation over Water, . 354
102. General Specifications of a Shipborne Navigational Radar 363
10.3,Anterma Assembly . . . . . . . . . . . . . . . . . ...364
10.4.Transmitter-receiver Package. 371
10.5.Indicator . . . . . . . . . . . . . . . . . . . . . . ...373
106. Power Supply . . . . . . . . . . . . . . . . . . . ...377
10.7.Physical Characteristics of the Components and Test Equipment 379
INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383
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