Satellite Ground Station Antennas E-Book

Roland Schwerdtfeger

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 576

Veröffentlichungsjahr: 2024

Beschreibung

Understand all aspects of ground station design with this groundbreaking volume

A satellite ground station is a terrestrial station built to communicate or receive signals from spacecraft and other astronomical and interplanetary sources. Since ground stations are subject to weather and other terrestrial conditions, their operations can be unpredictable, and their design offers numerous challenges for engineers.

Satellite Ground Station Antennas constitutes the first-ever comprehensive overview of these challenges and the tools by which engineers of all kinds can meet them. Analyzing every aspect of ground station antenna technology, the book can be read both continuously or as a reference, with each chapter functioning by itself to fully apprehend a discrete portion of the subject. Balancing mathematics with mechanics, it combines accessibility and rigor to create an unprecedented resource.

Readers will also find:

• In-depth material published in a fully accessible form for the first time
• Detailed discussion of topics including reflector design, structural considerations, proof-of-performance, and more
• Lavish illustrations and photographs throughout

Satellite Ground Station Antennas is ideal for electrical, mechanical, and civil engineers, as well as for any other industry professional working with ground station design.

Leseprobe

IEEE Press445 Hoes LanePiscataway, NJ 08854

IEEE Press Editorial BoardSarah Spurgeon, Editor-in-Chief

Moeness Amin

Jón Atli Benediktsson

Adam Drobot

James Duncan

Ekram Hossain

Brian Johnson

Hai Li

James Lyke

Joydeep Mitra

Desineni Subbaram Naidu

Tony Q. S. Quek

Behzad Razavi

Thomas Robertazzi

Diomidis Spinellis

Satellite Ground Station Antennas

Electrical, Mechanical, and Civil Engineering Design

Roland Schwerdtfeger

with

Thomas A. Milligan, Robert Hoferer, and Christophe Granet

Copyright © 2025 by The Institute of Electrical and Electronics Engineers, Inc. All rights reserved.

Published by John Wiley & Sons, Inc., Hoboken, New Jersey.Published simultaneously in Canada.

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Library of Congress Cataloging-in-Publication Data:

Names: Schwerdtfeger, Roland, author. | Milligan, Thomas A., author. |  Hoferer, Robert, author. | Granet, Christophe, author.

Title: Satellite ground station antennas : electrical, mechanical, and  civil engineering design / Roland Schwerdtfeger with Thomas A. Milligan,  Robert Hoferer and Christophe Granet.

Description: Hoboken, New Jersey : Wiley, [2025] | Includes index.

Identifiers: LCCN 2024026893 (print) | LCCN 2024026894 (ebook) | ISBN  9781394191710 (hardback) | ISBN 9781394191727 (adobe pdf) | ISBN  9781394191734 (epub)

Subjects: LCSH: Antennas (Electronics) | Earth stations (Satellite telecommunication)

Classification: LCC TK7871.6 .S375 2025 (print) | LCC TK7871.6 (ebook) |  DDC 621.382/4 – dc23/eng/20240730

LC record available at https://lccn.loc.gov/2024026893

LC ebook record available at https://lccn.loc.gov/2024026894

Cover Design: WileyCover Image: © Imagery by Thomas A. Milligan

Since the bulk of this work was prepared at home, my wife Marilyn essentially suffered many years from an uncommunicative presence writing and studying at the kitchen table. She has traveled with me to various antenna sites and has a measure of understanding of the issues. Therefore, it is fitting that this book be dedicated to her.

— Roland Schwerdtfeger

Memorial Biographical Sketch – Roland Schwerdtfeger

Born in Adelaide, Australia in 1941, the author attended the School of Engineering at McGill University in Montreal and graduated in 1963 with a BEng degree. An introduction to serious microwave engineering was acquired at RCA Victor Co. Ltd. under the leadership of Peter Foldes, while participating in a project for the first Canadian earth station in Mill Village Nova Scotia in 1965. Postgraduate studies on reflector antennas were undertaken at the University of Southern California (USC) with Dr Willard Rusch in 1979. A brief sojourn in Switzerland with Huber + Suhner AG permitted some consultative time with the Swiss PTT about a new earth station at Leuk. A new RF Lab was set up at H+S while developing a transportable C and Ku band man-pack antenna for the Swiss Army. From 1982 to 1983, he assisted Spar Aerospace in Montreal in their short escapade into the business of large earth station antennas. Scientific Atlanta supported entry into the United States. From 1984 to 1988, he was self-employed as a technical consultant. In 1988, the author started with Vertex Communications Corporation later General Dynamics SATCOM Technologies and now Communications & Power Industries – Antenna Technologies in Kilgore, Texas – initially as director of RF Development Labs, and since 2003, as director of RF Concepts and Technical Advisor. He was a life member of the IEEE.

Larger than life, Roland believed in mentoring both young engineers and his customers. This book is a memorial to his goal of teaching those who come after him. Roland died in May 2021.

The author at CSIRO’s impressive 64 m Radio Telescope in Parkes, NSW, Australia – 2007

About the Authors

Thomas A. Milligan has over 50 years of industrial experience in general antenna design and test. He is author of Modern Antenna Design (McGraw-Hill, 1985, 2nd ed. Wiley/IEEE Press, 2005, Chinese ed. 2012), co-author of Antenna Engineering using Physical Optics (Artech, 1996), and wrote the chapter “Numerical Techniques for Reflectors” (Artech, 2013). He served as the Artech antenna series editor for 10 years. An IEEE Life Fellow, AP-S President in 2000, he edited the “Antenna Designer’s Notebook” column in the IEEE Antenna Magazine for 21 years and served as an associate editor for the Transactions. For 14 years, he distributed and supported reflector antenna design and analysis software by TICRA used primarily for satellite communication. Previously Mr. Milligan worked for 34 years in antenna design, analysis, and test including many NASA’s planetary probes at Lockheed Martin Astronautics in Denver. He taught numerous publicly offered antenna short courses for over 30 years including general antenna design, phased arrays, measurement, and cellular antennas.

Dr. Robert Hoferer has over 30 years of experience in antenna feed systems and reflector antennas for satellite communications. He has been active as a Senior Member within the IEEE as the Chair for the Los Angeles AP-S chapter between 2013 and 2016, a member of the Industry Initiative Committee from 2012 to 2015, a reviewer for the AP-S Magazine, has published numerous conference papers and journal publications, and also holds two US patents. Since 1999, he worked at General Dynamics SatCom Technologies in different roles including Director of RF Engineering, Test Range Manager, and Type Approval Manager. He left in 2013 to join Spacetime Engineering as a co-founder and Chief Technology Officer.

Dr. Christophe Granet is an award winning antenna engineer with over 30 years of experience in the design, manufacture, and test of high-performance reflector antennas and feed systems for satellite communications, radio astronomy, and scientific applications. He was the recipient of the 2001 HA Wheeler Award from the IEEE Antennas and Propagation Society, and has published many peer-reviewed scientific papers and co-authored two book chapters on antenna design. From 1995 to 2008, he worked as a Principal Research Scientist at the CSIRO Radiophysics, Laboratory and then in 2008 left to join BAE Systems Australia as a Senior Antenna Specialist. In 2015, he left BAE Systems to start Lyrebird Antenna Research Pty Ltd. Christophe is a Senior Member of the IEEE.

Preface

Billions of people depend daily on the essential technology of satellite ground station antennas. This monograph captures the entire technology in all its aspects. It includes material for engineers specifying, designing both the RF and weather protection, overseeing site construction, and doing the final compliance testing of satellite ground station antennas. Managers planning these projects will find the help they need. You could read the book from cover to cover, but you can just as easily read the material required for your assignment. If a mathematical derivation is confusing, you lack the background, or it seems unimportant to you, skip it, and read on. You will not miss much. It takes a team of experts to specify, design, construct, and test a satellite ground station.

Roland Schwerdtfeger, a lifelong learner, focused on satellite ground stations. He started early doing limited hands-on design of small elements. Meanwhile, he slowly learned all aspects of the total system as he expanded his interest in the components of design. His unbounded curiosity led him to devise methods for the final testing of the completed installation. As older engineers left the field, he took on the responsibility of teaching younger engineers all he had learned by either absorbing what his predecessors had taught him or educating himself when new requirements arose. Customers and their engineers who specified the system needed to understand how to generate meaningful specifications so he started teaching them. This book began with Roland’s manuscript and his collection of additional material.

Located in Roland’s additional material we found further revisions because he was always improving his presentation. Companies building antennas today shared with us information about their manufacturing methods. The three of us from industry, who worked with Roland, have taken on two tasks: updating his material to include newer designs and methods revolutionizing the field, and the details of book production while correcting small errors.

Chapter 1 covers specifying the communication system from satellite geometry, propagation of signal including polarization, channel capacity, and limitations of environmental and equipment-generated noise to generate antenna size for a particular frequency of operation. The following four chapters illustrate design methods: reflectors, feeds, and construction methods including ground positioners. Chapter 6 shows the performance effects of weather protection including radomes. Radiation transmitted by the antennas affects neighboring communication and possible personnel radiation hazards. The final chapter gives the methods of final testing including the use of radio stars.

The authors hope the book will serve as a continuing source of design methods.

Thomas A. MilliganRobert HofererChristophe Granet

Acknowledgments

Marilyn Schwerdtfeger retained and provided Roland’s computer files and documents that made this book possible. Marc R. Björkman and Roy Passfield explained digital communication used in satellite data (TV) transmission. William D. Ashton provided help with civil engineering structures and foundations used in ground stations. Furthermore, the following contributors provided many valuable photos contained in this book to better illustrate the various aspects of a reflector antenna: Alex Dunning (CSIRO), Fred Vinezeano (Kratos Antenna Solutions, Inc.), Lutz Stenvers (mtex antenna technology), Bill Lawyer and Joe Baird (Viasat, Inc.), Dan Grzesik and Gene Sorgi (Challenger Communications, LLC), and Alan Pollard (Communications & Power Industries LLC).

Glossary of Terms

Item

Meaning

ACU

Antenna control unit

AIAA

American Institute of Aeronautics and Astronautics

ANSI

American National Standards Institute

a.r. or A.R.

Axial ratio (in dB)

ATIS

Automatic terminal information service

Az or az or Azim

Azimuth

b/a

Aspect ratio (of waveguide)

BDF

Beam deviation factor

bw

Bandwidth

bw/g

Beam waveguide

C

Celsius (temperature scale)

C-band

5.85–8.2 GHz

CCIR

Comité Consultatif International de la Radio (forerunner to ITU-R)

CCW or ccw

Counterclockwise

CFR

Code of Federal Regulations (USA)

C/N

Carrier-to-noise ratio or dynamic range (of signal)

Coax. or coax

Coaxial line

Ch. or ch.

Channel

con-scan

Conical scan

Co-pol or co-pol

Co-polarized

CP or cp

Circular polarization

CP/LP or cp/lp

Switch from circular to linear polarization

cps

Cycles per second (frequency unit)

CSIRO

Commonwealth Scientific and Industrial Research Scientific Organisation (Australia)

Cross-pol

Cross-polarized

CSU

Colorado State University (USA)

CW or cw

Clockwise

D

Diplexer

dB

Decibel

dBc

Decibel relative to the carrier level

dBi

Decibel relative to isotropic

dBK

Decibel relative to 1 Kelvin

dBm

Decibel relative to 1 milliWatt

DBS

Direct broadcast satellite (service)

dBW

Decibel relative to 1 Watt

DC

Direct current

deg

Degree (angular measurement)

DNC or d/c

Down converter

DPS or diff. ph. sh.

Differential phase shift(er)

DSF

Dielectric space frame

E or E-field

Electric field

EHF

Extremely high frequency

EIA

Electronic Industries Association (USA)

eirp or EIRP

Effective isotropic radiated power

El or el or Elev

Elevation

e-m

Electromagnetic

E-plane (bend)

Waveguide component

Eq

Equation

ET

Earth terminal

es or ES

Earth station

F

Frequency (as hertz or cps)

FCC

Federal Communications Commission (USA)

F/D or f/d

Focal length/reflector aperture diameter ratio

FoV

Field of view

FSS

Frequency selective surface

G

Antenna gain

GEO

Geostationary earth orbit

GEO

Global equatorial orbit

GHz

Gigahertz

GMT

Greenwich mean time

GSO

Geostationary satellite orbit

G/T

Antenna gain/noise temperature ratio

H

Magnetic field

H

Horizontal polarized signal component

HA

Hour angle

HLP

Horizontal linear polarization

HPA

High power amplifier

HPF

High pass filter

H-plane (bend)

Waveguide component

H-pol or Hor. pol

Horizontal polarization (of signal)

H + S

Huber and Suhner AG (Switzerland)

ICSC

International Satellite Communications Commission

IEEE

Institute of Electrical and Electronics Engineers (USA)

IESS

Intelsat Earth Station Standards

IF

Intermediate frequency

IFL

Interfacility link

IM

Intermodulation

IMP

Intermodulation products

i/o

Input/output

IOT

In-orbit test

i/p

Input

IRE

Institute of Radio Engineers (USA)

ISRO

Indian Space Research Organization

ITU-R

International Telecommunications Union – Recommendations (USA)

JPL

Jet Propulsion Laboratory (USA)

K

Kelvin (temperature scale)

k

Beam deviation factor

K-band

18–26.5 GHz

Ka-band

26.5–40 GHz

kHZ

Kilohertz

Ku-band

12–18 GHz

Kt-band

17.7–21.2 GHz

La or la

Latitude

L-band

390 MHz–1.5 GHz

LCP

Left-hand circular polarization

LEO

Low earth orbit

LHA

Local hour angle (of star)

LNA

Low noise amplifier

Lo or lo

Longitude

LP or lp

Linear polarization

LPF

Low pass filter

MEO

Medium earth orbit

MHz

Megahertz

MOD

Modulation (of slope performance)

MIL

Military standard (USA)

MIT

Massachusetts Institute of Technology (USA)

MSF

Metal space frame

MSL

Mean sea level

MSS

Mobile satellite service

MT

Magic tee

MTT

Microwave theory and techniques

NBS

National Bureau of Standards

NF

Noise figure

NIST

National Institute of Standards and Technology (USA)

NOAA

National Oceanic and Atmospheric Administration (Vermont, USA)

OMT

Orthomode transducer or orthocoupler

PA

Power amplifier

PC

Phase center

PD

Polarization discrimination

PF

Packet filter

pfd

Power flux density

Ph

Reference or “hot load” noise power

ph. sh.

Phase shift

PIM

Passive intermodulation

PL

Path loss

pol angle

Polarization rotation angle

p–p

Port to port

PR

Power ratio

Pre-preg

Pre-impregnated

psf

Pounds per square foot (pressure)

psig

Pounds-force per square inch gauge

PTFE

Polytetrafluoroethylene (used in Teflon)

PTT

Postal Telegraph and Telephone (Switzerland)

Q-band

33–60 GHz

QJ

Quadrature junction

R

Ratio of one or more voltage axial ratios

r

Voltage axial ratio

RA

Right ascension (of star)

RAS

Royal Astronomical Society (England)

RBW

Resolution band width

RCA

Radio Corporation of America

RCP

Right-hand circular polarization

RF

Radio frequency

RH

Relative humidity

RL

Return loss

rms

Root mean square

RRF

Receiver frequency rejection filter

Rx

Receiver

sat.

Satellite

S-Band

2.6–3.95 GHz

SGH

Standard gain horn

SLE

Sidelobe envelope

SMA

Subminiature coax line connector

S/N

Signal-to-noise ratio

SOTM

Satellite communication on the move

s-pol

satellite polarization

SSM

Satellite system monitor

SSPA

Solid state power amplifier

Subref.

Sub-reflector

Sw

Switch

T

Temperature (in Celsius or Kelvin)

Tc

Cold load noise temperature

TE

Transverse electric wave

TEM

Transverse electromagnetic wave

Th

Hot load noise temperature

THz

Terahertz

TM

Transverse magnetic wave

TRF

Transmit frequency rejection filter

Ts

System noise temperature

TTC

Telemetry tracking and control

TWTA

Travelling wave tube amplifier

Tx

Transmitter

UER

Upper equipment room

USC

University of Southern California (USA)

UTC

Coordinated universal time

V

Vertical polarized signal component

VAR or var

Voltage axial ratio (of antenna)

VBW

Video bandwidth

VHF

Very high frequency

VLP

Vertical linear polarization

VP

Vertical polarization

V-pol

Vertical(ly) polarized signal

VSAT

Very small aperture terminal (network)

VSWR

Voltage standing wave ratio

w/g or W/G

Waveguide

X-band

8–12 GHz

Xpol or xpol

Cross-polarization

X–Y

Elevation over cross-elevation (positioner)

y-factor

Noise power ratio

Zee or Z

Flexible stiffener (for antenna)

Zf

Feed axis

Zm

Main reflector axis

Zs

Sub-reflector axis

Introduction

Objective

This book discusses microwave reflector antennas for satellite communications. Microwaves cannot be sensed, making it difficult to develop an intuitive understanding of their nature and behavior. While many individuals and enterprises may operate satellite links, they may only have a rudimentary understanding of how the microwave antennas of these links function. Young engineers with university training in microwave theory may lack the experience to identify the appropriate design approach or to understand individual or idiosyncratic performance problems once a design is complete. Technicians without substantial physical and mathematical education or experience in microwave antenna and feed system design can be frustrated by assembling and testing components and systems designed by others.

Antenna theory uses complicated mathematics and concepts which make reading technical publications difficult. The authors assume readers have some background in electromagnetics where power radiation is discussed.

The antenna shape and size determine the directional distribution (pattern) of radiated power. Antennas constructed from linear (properties do not depend on power level) and isotropic (no directional properties) materials radiate and receive the same pattern. Transmission lines connect antenna terminals from transmitter to receiver with some power lost in materials or reflected at impedance mismatches.

Antenna design is determined by signal pattern requirements. Interference can be created by physical objects or other signals using the same frequency. This book provides techniques to optimize signal radiation and minimize interference without the use of complicated mathematics.

Short History

Commercial satellite communications started in the early 1960s using the C-band 5.925–6.425 GHz uplink and 3.7–4.2 GHz downlink. The United States, Canada, Britain, Germany, France, and Spain contributed earth station antenna systems to communicate with the first Low Earth Orbit (LEO) satellite called Relay. Coincidentally, each of these antennas adopted the same radio frequency (RF) design approach.

US – Andover Maine – Bell Telephone – a 67 ft horn reflector

Canada – Mill Village, Nova Scotia – Dept of Transport – a classic 85 ft Cassegrain

Britain – Goon Hilly – British Post Office – 25 m prime focus

Germany – Raisting – German Post Office – 25 m two reflector quasi-beam waveguide Cassegrain

Low satellite power prompted large antenna sizes and low feed losses. In 1965, the first of the Global Equatorial Orbit (GEO) stationary satellites became available. These satellite operations soon were placed under the control of an international organization called Intelsat. In the 1970s, Intelsat “Standard A” antenna sizes increased to 32 m to accommodate lower antenna operation cost demands, yet maintain received signal quality. As the number of satellites increased, interference from neighboring satellites forced antenna designs to possess low-level sidelobes. Additionally, dual polarization techniques increase communication capacity, prompting low cross-pol characteristics to minimize same satellite interference.

Deep space communication with spacecraft and radio telescopes operating from 100 MHz to 1 THz, continue to use very large, fully steerable precision reflector antennas. These antennas may be up to 100 m in size, and equipped with cryogenically cooled low-noise amplifiers to suppress the system noise floor to the absolute minimum.

In the 1980s, Intel standards expanded communication channels, antenna designers introduced the 11–13 m C-band “Intel Standard-B”, and the 13 m Ku-band “Intel Standard C” with 14.0–14.5 GHz uplink and 10.95–12.75 GHz downlink. Satellite power levels increased. Smaller 4.5–6.1 m Ku-band, small 2.4–4.5 m Ku antennas were created for low-capacity applications such as banking, public TV broadcast, and direct satellite-to-home broadcast at C-band. Remote earth sensing satellites for scientific and meteorological purposes adopted the S-band and the upper X-band. Military interests adopted the single polarized X-band 7.9–8.4 GHz uplink and 7.25–7.75 GHz downlink in 20, 38, and 60 ft Cassegrain antennas. These designs were accompanied by special antennas for Milstar satellites working Ka/Q bands 20.2–21.2 GHz downlink and 43.5–45.5 GHz uplink. Other obscure frequency bands followed for very high gain surveillance applications at the Kt/Ka bands. Beginning in the 1990s, satellites simultaneously operated multiple frequency bands such as C and Ku, L and C, S and X, S and Kt, X and Ku, Ku and Ka, and even C+X+Ku and C+Ku+Ka bands, as well as multi-beam antennas to link with several satellites simultaneously.

Due to the global nature of earth station performance, independent regulatory agencies have been established by international government agencies to ensure that satellite links do not interfere with each other. The Federal Communications Commission (FCC) in the United States and Eutelsat in Europe, as well as several regional organizations, dictate uplink flux densities, sidelobe envelope, and cross-pol performance. Communications owners dictate the G/T (gain/noise temperature K) and uplink power handling based on link budgets calculated on specific satellites. Special antenna systems for Telemetry, Tracking and Control (TTC), and In-Orbit Test (IOT) functions monitor the health of an orbiting satellite and are in continuous operation. They demand high-precision, calibrated antenna designs to establish the exact position of a target satellite and measure its receive and transmit performance.

Once, costs of antenna instruments were of secondary consideration; performance was the first. Today, costs are of paramount importance. Many antenna operators are now faced with changing satellite links involving new frequency bands and functions, and for financial reasons want to convert existing antennas. However, there are many problems with this approach, and antenna designers must be able to understand the consequences of damaged antennas, constraints in reusing existing feeds, and polarization and frequency compatibility.

Since 1962, satellite Effective Isotopically Radiated Power (EIRP) has increased from less than 0 dBm to >50 dBW. Earth-based reflector antennas have become smaller: from 32 m at C-band to 50 cm at Ku-band. This has sparked a need for Satellite Communications On-The-Move (SOTM): vehicle-mounted communications. These small multi-function antennas demand new RF and mechanical packaging design concepts and methods. In the future, reflector antennas will need to offer increasingly wider frequency bandwidths and lower losses in ever more compact packages, involving new waveguide components.

Requirements to Produce Microwave Reflector Antennas

Antenna manufacturing is a team effort involving multiple disciplines:

Precision fabrication of mechanical parts and structure based on good engineering design

Comprehensive understanding of microwaves and the components used to control them, including reflector optics

Interface engineering

Electrical and mechanical measurement techniques to establish proof-of-performance

Team members often work on several antenna projects at once, all with constrained timelines for completion. The necessary disciplines of an engineer working in commercial industry can be summed up with the following list:

Evaluate the customer’s request and understand the mission for the antenna system

Propose an effective technical solution that encompasses performance and cost requirements

Generate a detailed plan with delivery estimates of all actions needed to complete the work

Educate the customer and colleagues during technical reviews

In particular, the engineer must be able to communicate their concepts, methods, and design philosophy to new members of the technical staff to ensure organizational consistency. This book seeks to form a foundation for continued education in microwave reflector antenna engineering by summarizing the elements of successful product delivery.

This book introduces antenna system design by considering orbit geometry and communication capacity requirements in a particular allocated frequency band. While this book focuses mainly on geostationary satellite communications, the methods given can be applied to satellites at any altitude. Lower altitude satellites require tracking antennas to follow the passing satellite, but even geostationary satellites move in a figure-eight N–S pattern and may require tracking in higher frequency bands. Quality of communication drives the antenna design and transmitter power requirements when unavoidable noise is considered. Once the basic gain and pattern shape requirements are established, we move to design trade-offs. Chapter 2 considers types of reflector antennas using our approach, restricted to the inexpensive aperture type antennas as opposed to phased arrays. Chapters 3 and 4 consider reflector feeds: first for antennas either with a fixed pointing direction or slowly moving pointing requirements (Chapter 3) or reflectors with tracking mounts (Chapter 4). Chapter 5 considers elements of the structure of the antenna and its mount to withstand dead weight loading and weather (wind, rain, etc.) if not protected. Chapter 6 illustrates methods of protecting the reflector antenna from weather using radomes that affect performance. Radiation safety and interference between multiple closely spaced reflector antennas is considered in Chapter 7. Chapter 8 expounds on the challenges presented by electrically large antennas during final proof-of-performance testing and includes application of radio star measurement techniques.

1Antenna System Analysis

1.1 Introduction

Chapter 1 introduces