Model 3147
Log Periodic
Dipole Antenna
User Manual
ETS-Lindgren L.P. reserves the right to make changes to any product described
herein in order to improve function, design, or for any other reason. Nothing
contained herein shall constitute ETS-Lindgren L.P. assuming any liability
whatsoever arising out of the application or use of any product or circuit
described herein. ETS-Lindgren L.P. does not convey any license under its
patent rights or the rights of others.
© Copyright 1999–2010 by ETS-Lindgren L.P. All Rights Reserved. No part
of this document may be copied by any means without written permission
from ETS-Lindgren L.P.
Trademarks used in this document: The ETS-Lindgren logo is a trademark of
ETS-Lindgren L.P.
Revision Record
MANUAL 3147 LOG PERIODIC ANTENNA | Part #399160, Rev. F
Revision Description Date
A Initial Release January, 1999
B Updated content/branding October, 2002
C Edited content, rebranding changes June, 2008
D Updated photos April, 2009
E Added Mounting Instructions March, 2010
F Corrected error in Power
Requirements table; updated part
numbers in Mounting Instructions
ii |
November, 2010
Table of Contents
Notes, Cautions, and Warnings ................................................ v
1.0 Introduction .......................................................................... 7
Regarding Calibration of Log Periodic Dipole Antennas ................................ 8
ETS-Lindgren Product Information Bulletin ................................................... 9
2.0 Maintenance ....................................................................... 11
Maintenance Recommendations ................................................................. 11
Annual Calibration ....................................................................................... 11
Service Procedures ..................................................................................... 11
3.0 Specifications ..................................................................... 13
Electrical Specifications ............................................................................... 13
Physical Specifications ................................................................................ 13
4.0 Mounting Instructions ....................................................... 15
Using Included Mounting Adapters .............................................................. 15
Additional Mounting Options ........................................................................ 17
4-TR Mounting Options ................................................................................ 17
7-TR and Mast Mounting Options ................................................................ 18
2x2 Boom Mounting Options ....................................................................... 19
5.0 Operation ............................................................................ 21
Model 3147 Assembly Instructions .............................................................. 21
Model 3147 Use ........................................................................................... 21
6.0 Typical Data ........................................................................ 23
Typical VSWR for Model 3147 ..................................................................... 23
Typical Antenna Factor and Gain for Model 3147 ....................................... 24
Beamwidth for Horizontally and Vertically Polarized Model 3147................ 26
Front-to-Back Ratio for Model 3147 ............................................................. 28
Cable Attenuation (dB) at 20°C for 6-M Cable ............................................. 29
Typical Antenna Pattern for 200 MHz and 300 MHz ................................... 30
7.0 Radiated Emissions Measurement .................................. 31
Conversion Factors ...................................................................................... 32
8.0 Power Requirements ......................................................... 35
Power Requirements Table ......................................................................... 36
| iii
80 Watts Continuous Power ........................................................................ 36
40 Watts Continuous Power ........................................................................ 38
Appendix A: Typical Antenna Patterns ................................. 41
400 MHz ...................................................................................................... 41
500 MHz ...................................................................................................... 41
600 MHz ...................................................................................................... 42
700 MHz ...................................................................................................... 42
800 MHz ...................................................................................................... 43
900 MHz ...................................................................................................... 43
1.0 GHz ........................................................................................................ 44
1.5 GHz ........................................................................................................ 44
2.0 GHz ........................................................................................................ 45
2.5 GHz ........................................................................................................ 45
3.0 GHz ........................................................................................................ 46
3.5 GHz ........................................................................................................ 46
4.0 GHz ........................................................................................................ 47
4.5 GHz ........................................................................................................ 47
5.0 GHz ........................................................................................................ 48
Appendix B: Warranty ............................................................. 49
iv |
Notes, Cautions, and Warnings
Note: Denotes helpful information intended to
See the ETS-Lindgren Product Information Bulletin for safety,
regulatory, and other product marking information.
provide tips for better use of the product.
Caution: Denotes a hazard. Failure to follow
instructions could result in minor personal injury
and/or property damage. Included text gives proper
procedures.
Warning: Denotes a hazard. Failure to follow
instructions could result in SEVERE personal injury
and/or property damage. Included text gives proper
procedures.
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vi |
1.0 Introduction
The ETS-Lindgren
Model 3147 Log Periodic
Dipole Antenna is a
linearly-polarized broadband
antenna designed to operate
over the frequency range of
200 MHz to 5 GHz. The
antenna was designed with
the latest revision to Part 15
of FCC Rules and
Regulations in mind. See
page 13 for specifications.
The Model 3147 is constructed from 30 elements mounted on two 6.35-mm by
12.7-mm booms. The choice of scaling factors, the various diameters of each
element, and the center-to-center spacing of the booms yield excellent VSWR
characteristics throughout the operating frequency range (see VSWR on
page 23). The precise design of the feed and the positioning of the elements on
the boom yield an optimum phase relationship. This causes the active region, at
any given frequency, to propagate RF energy towards the smaller elements,
leaving the elements behind it electrically dead.
The constant gain of the Model 3147 yields an antenna factor which varies
linearly with frequency, as shown in Typical Data on page 23. The variation is
smooth; therefore, accurate interpolation of performance between specified
frequency points is simple.
Due to the relatively high upper frequency limit, the small elements on the
Model 3147 are very thin. The antenna is equipped with an integral, low
dielectric-constant radome to protect the elements from possible damage.
Do not disassemble or drop the antenna or the
thin elements may be damaged.
Introduction | 7
Because the radome is almost RF-invisible, it has very little effect on the
performance of the Model 3147 (see VSWR on page 23).
The base of the Model 3147 accepts an ETS-Lindgren or other tripod mount with
1/4–20 threads. Additionally, the antenna is shipped with a support rod. A variety
of mounting options are available for the Model 3147. For information, see
Mounting Instructions on page 15.
Regarding Calibration of Log Periodic Dipole Antennas
To meet the requirements of two different specifications, this log periodic dipole
antenna was calibrated at two different spacings.
• SAE ARP 958 (Society of Automotive Engineers, Aerospace
Recommended Practice) requires an antenna spacing of one meter,
measured tip to tip.
• ANSI 63.5 requires a spacing of three and ten meters measured from
the projection onto the ground plane of the midpoint of the longitudinal
axis of the antenna.
The ARP and the ANSI requirements disagree because these standards were
written for different purposes. Therefore, when calibrating the log periodic array
antennas per ARP 958, ETS-Lindgren measures from tip to tip and sets the
spacing to one meter. When calibrating the log periodic array antennas per
ANSI C63.5, ETS-Lindgren measures from the midpoint to the midpoint of the log
periodic antennas for 3-meter and 10-meter calibrations.
It is important in compliance demonstration testing to measure the
spacing from the antenna to the Equipment Under Test (EUT) as it
was measured when calibration was performed.
For additional information, contact ETS-Lindgren.
8 | Introduction
ETS-Lindgren Product Information Bulletin
See the ETS-Lindgren Product Information Bulletin included with your shipment
for the following:
• Warranty information
• Safety, regulatory, and other product marking information
• Steps to receive your shipment
• Steps to return a component for service
• ETS-Lindgren calibration service
• ETS-Lindgren contact information
Introduction | 9
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10 | Introduction
2.0 Maintenance
Before performing any maintenance, follow the
safety information in the ETS-Lindgren
Product Information Bulletin included with your
shipment.
Maintenance of the Model 3147 Log Periodic Dipole Antenna is limited to
external components such as cables or connectors. If you have any questions
concerning maintenance, contact ETS-Lindgren Customer Service.
Maintenance Recommendations
If the Model 3147 is used outdoors, periodic removal of the antenna cable
connection and cleaning of any corrosion may be needed to maintain accuracy of
the measurements. An inspection to determine the need for cleaning should be
made at least every six months. More frequent inspection may be needed
depending on the atmosphere and the environment in which the antenna is used.
Annual Calibration
See the Product Information Bulletin included with your shipment for information
on ETS-Lindgren calibration services.
Service Procedures
For the steps to return a system or system component to ETS-Lindgren for
service, see the Product Information Bulletin included with your shipment.
Maintenance | 11
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12 | Maintenance
3.0 Specifications
Electrical Specifications
Frequency Range: 200 MHz–5 GHz
VSWR: Average: 1.25:1
Impedance: 50 Ω
Maximum: 1.7:1
Maximum Continuous
Input Power:
Maximum Peak Input Power: 100 W at 1 GHz
Connector: Precision N female
80 W at 1 GHz
40 W at 5 GHz
50 W at 5 GHz
Physical Specifications
Height: 7.62 cm
3.0 in
Width: 88 cm
34.65 in
Depth: 97 cm
38.19 in
Weight: 4.25 kg
9.36 lb
Specifications | 13
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14 | Specifications
4.0 Mounting Instructions
Before connecting any components, follow the
safety information in the ETS-Lindgren
Product Information Bulletin included with your
shipment.
The Model 3147 is a precision measurement
device. Handle with care.
Using Included Mounting Adapters
The Model 3147 Log Periodic Dipole Antenna ships with these mounting
adapters:
• 100989 Polarizing Mounting
Adapter with 7/8–14 thread
receptacle
If you need to convert the polarizing
adapter to a 1/4–20 receptacle,
insert the 1/4–20 thread insert into
the polarizing adapter
• 105861 1/4–20 Thread Insert
Mounting Instructions | 15