1、ANSI/EIA-411 -A-1986 APPROVED JULY 7, 1986 ELECTRICAL AND MECHANICAL CHARACTERISTICS OF EARTH STATION ANTENNAS FOR SATELLITE COMMUNICATIONS EIA STANDARD EIA-411-A (REVISION OF EIA-411) SEPTEMBER 1986 Engineerw Peporhnent ELECTRONIC INDUSTRIES ASSOCIATION j EIA 411-A 86 m 3234600 O068013 8 m NOTICE E
2、IA Engineering Standards and Publications are designed to serve the public intetest through eliminating misunderstandings between manufacturers and purchasers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the p
3、roper product for his particular need. Existence of such Standards and Pub- lications shall not in any respect preclude any member or non-member of EIA from manufacturing or selling products not conforming to such Standards and Publications, nor shall the existence of such Standards and Publications
4、 preclude their voluntary use by those other than EIA members, whether the standard is to be used either domestically or internationally. Recommended Standards and Publications are adopted by EIA without regard to whether or not their adoption may involve patents on articles, materials, or processes
5、. By such action, EIA does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopting the Recom- mended Standard or Publication. This Recommended Standard is considefed to have international standard- ization implications, but the IEC activity has.no
6、t progressed to the point where a valid comparison between-the EIA Recommended Standard and the IEC Recommendation can be made. * Published by ELECTRONIC INDUSTRIES ASSOCIATION Engineering Department 2001 Eye Street, NW Washington, D.C. 20006 Copyright 1986 All rights reserved ELECTRONIC INDUSTRIES
7、ASSOCIATION PRICE: $40.00 Printed in U.S.A. Y, EIA 411-A 86 m 3234600 0068014 T m EIA-411-A PREPACE The objectives of EIA-411-A, Electrical and Mechanical Characteristics of Earth Station Antennas for Satellite Communications,“ are the following: (a) to provide standard terms, definitions, and conce
8、pts for the mechanical and RF design of earth station antennas, and (b) to offer a standard methodology for the verification o RF performance compatible with current technology and test equipnent. The standards are not intended to replace or supersede applicable codes. The information contained in t
9、hese standards was obtained from information and data as referenced and noted herein and represente, in the judgment of the subcommittee, the accepted industry practices for definition and standards for the design and testing of satellite corrmunications antennas Specific values for parameters such
10、as gain, sidelobe level, safe wind loading etc., are not given because the acceptable values depend on the application and the system configuration. This industry standard does provide users as well as manufacturers with a common language for the preparation of specifications, proposals, and test ro
11、utines. i PRDBLEM HARD COPY EIA 411-A 8b m 3234b00 00b8015 1 m .4? - EIA-411-A ELECTRICAL AND MECHANICAL CIIARACTERISTICS OF EARTH STATION ANTENNAS FOR SATELLITE COIMINICATIONS TABLE OF CORERTS Ch8Dtct 1 ELECTRICAL RF 1 . 1 Int roduc t ion 1.2 Earth Station Antenna 1.3 Antenna Gaia 1.4 1.5 1.6 1.7 1
12、.8 1.9 1.10 1,11 1.12 Antenna Noise Temperature Antenna System G/T Antenna Pattern Antenna Feed System Frequency Band Reflection Coefficient Return-Loee, and VSWR Port-to-Port Isolation Ohmic Loss (Insertion Loss) Polarization 1.12.1 Axial Ratio 1,12.2 Polarization Efficiency 1.12.3 Polarization Iso
13、lation (Discrimination) 2 1.13 Group Delay 1.14 Power Rating 1.15 Radiation Hazard CONTROL SYSTEMS 2.1 General 2.2 Applicable Standards 2.3 Modes of Operation P.gc 1-1 1-1 1-3 1-3 1-4 1-5 1-6 1-6 1-7 1-7 1-7 1-8 1-9 1-11 1-11 1-14 1-20 1-21 1-22 2-1 2-1 2-3 2-4 EIA 411-A 8b = 3234600 OOb8OLb 3 EIA-4
14、114 - TABLE OF COIOTS - Coatiauad I. .i . , I JI Chapter 2.4 Performance Requirements 2.4.1 Angular Coverage 2.4.2 Dynamics 2.4.2 1 Target Dynamics 2.4.2.2 Antenna Dynamics 2.4,2.3 Slew Dynamics 2.4.2.4 Stow Dynamics 2.4.2.5 Control Steering rrr 2.4.2.6 Control System Stability 2.4.2,7 Transient Per
15、formance 2,4.2.8 Locked Rotor Frequency 2.5 Safety Requirements 2.5.1 Travel Limits 2.5.2- Stow IateriocKs 2.5.3 Emergency Interlocks 2.5.4 Handcrank Interlocks 2.5.5 Reflector Access Interlock 2.5.6 Audible Motion Alarm .- 2,6 System Monitoring 2.6.1 Mode Selection 2.6.2 Position Display 2.6.3 Stat
16、us Display 2.6.4 Parameter Display 2.7 Computer Control and Monitor 3 Pointing and Tracking Accutacy 3.1 General 3,2 Pointing Accuracy 3.3 Tracking Accuracy 3.3.1 Tracking for Gain Accutacy 3-, 3 2 Tracking for Spat ia1 Coorciinates Accuracy s ri Page 2-5 2-5 2-6 2-6 2-6 2-6 2-7 2-7 2-7 2-8 2-8 2-11
17、 2-11 2-11 2-12 2-12 2-12 2-3 2-13 2-13 2-13 2-14 2-16 2-14 3-1 3-1 3-3 3-3 3-3 3-5 . iii -) PROBLEM HARD COPY 2 EIA 411-A 6 M 3234600 00b01 7 M EIA-4 ll-A Chapter 5 4.3 4.4 4.5 4.6 4.7 4.8 TABLE OF CONTENTS - Continued- 4.2.3 Appl ic able Standards 4.2.4 Natural Frequency 4.2.5 Safety Factors Struc
18、tural 4.3.1 Survival 4.3.2 Standard 4.3.3 Applicable Standards Factors Affected by Environment 4.4.1 Structure 4.4.2 Wind and Wind Gusts 4 4.3 Wind Loading 4.4.4 Earthquake 4.4.5 Drive System 4.5.1 Operational Requirements 4.5.2 Stow Requirements Mechanic a 1 Equipment Electronic Equipment Foundatio
19、ns and Anchot Bolts D 4.8.1 Design Loads 4.8.2 Stiffness 4.8.3 Soil Properties 4.8.4 Standard Foundations Operational Requirements of the StruCture 4.8.4.1 Uplift Resistnce 4.8.5 Nonstandard Conditions 4.8.6 Foundat ion Drawings ENVIRONMENTAL 5.1 General 5.2 Wind Velocity 5.2.1 Wind Gusts Page 4-8 4
20、-9 4-9 4-9 4-9 4-10 4- 10 4-11 4-11 4-11 4- 12 4-24 4-24 4-26 4-26 4-26 4-27 4-27 4-27 4-27 4-27 4-28 4-28 4-28 4-29 4-29 5-1 5-1 5-1 5-1 - PKOBLEM HARD COPY - and f, Phase center data. The radiation pattern and phase-center data on the primary feed can be used to predict many of the critical parame
21、ters of the secondary antenna system. If it is assumed that the antenna geometry is properly aligned and quantita- tive knowledge of the alignment accuracy is available the following informa- tion can be derived: o Gain and G/T: typical accuracy approximately k0.5 dB o First sidelobe levels: probabl
22、e accuracy I1 dB (at 15 dB level) Wide-angle sidelobe: qualitative estimate of the sidelobe envelope o Axial ratio: qualitative estimate of levels. EIA 411-A 86 m 3234600 0068025 4 m EIA-4 ll-A 1.2 EARTB STATION A#TEI9#A e Definition: The Satellite Communication Earth Station Antenna is a device tha
23、t transfers RF energy from a transmission line to free space and/or vice versa. The antenna in its simplest form consists of four main subsystems: a. The radiating system consisting of a single reflector or multiple reflectors or a lens b. The feed system or the launcher for RE energy c. The antenna
24、 support structure with a pedestal d. The antenna positioning control system. Standard: It shall be standard to specify al1 electrical and mechanical param- eters for any antenna. P .a mEm GAIR Definition: The antenna gain is defined as the ratio of the maximum power density produced at a larga dist
25、ance to the power density produced at the same distance by an isotropic radiator with matched polarization of 100 percent efficiency having the same input power as the antenna under test. The gain of an antenna is defined in the far zone radiation field of the antenna. it is usually expressed in dec
26、i- bels referred to isotropic (dBi). The same term is also applied to receiv- Note: I ing antennas. Standard: It shall be standard to specify the gain for specific frequencies and the polarizations of interest. It shall be standard to specify the points in the antenna system at which the transmit an
27、d receive gain are to be measured or referenced. Note: The extent to which filters, couplers, switches and other components in the transmission line losses are to be included in the gain computation and measurement shall be speci- f ied. a 1-3 EIA 411-A 86 H - 3234600 0068026 6 Em-411-A It shall be
28、standard in a steerable antenna system to specify the operating angles at which the specified gain is to be achieved. It shall be standard to specify the environmental condition under which the speci- fied gain is to be achieved. It shall be standard to specify the VSWR of the antenna. 1.4 ANTENNA O
29、LSB TEHPERATURE Definition: The noise temperature expressed in Kelvin at a specific frequency, is equal to the effective temperature of a passive matched load having an equal available noise power output per unit bandwidth. It is defined in the following relationship: N = kT where N is the available
30、 noise power output per unit bandwidth in watts/Hz, k is the Boltzmanns constant in watts/Kelvin Hz, and T is the noise temperature in Kelvin. Standard: It shall be standard to specify the antenna noise temperature at the feed output flange, including all feed contributions. Any active circuit eleme
31、nts (e.g. amplifiers, detectors) shall not be included. It shall be standard to specify the noise temperature for specific frequencies and polarization. It shall be standard to specify antenna noise temperature at the same point in the antenna as the antenna gain is specified. It shall be standard t
32、o specify noise temperature versus elevation angle the horizon. above 1-4 - - EIA 411-A 6 W 3234600 0068027 EIA-411-A If antenna system noise temperature is specified it shall be standard to also include the effects of the active circuit elements (e.g. amplifiers, detectors), noise contribution of t
33、he interconnecting transmission lines between the feed output and the active circuit elements as well as their VSWR. It shall be standard to specify the environmental conditions under which the specified noise temperature is to be achieved. NOTE: These requirements need not be the full environmental
34、 requirements specified for the antenna system. 1 e5 ANTENNA SYSTEM G/T Definition: The G/T (or Figure of Merit) o an antenna system is the ratio of the receive antenna gain to the system noise temperature when referred to the same point in the system and expressed in decibels (dB). 1 Antenna Gain (
35、power ratio relative to Isotropic) System Noise Temperature (Kelvin) G/T = io loglo or 1 System Noise Temperature C/TI dBK = Antenna Gain This equation expresses the G/T of the antenna system under consideration as a ratio, referred to a reference antenna system whose (antenna gain)/(system noise te
36、mperature) ratio is equal to unity. Standard: t shall be standard to specify the G/T of the antenna system at the elevation angle(s), frequency(ies), and polarization of interest. It shall be standard to specify the conditions under which the test is to be performed, if G/T is to be demonstrated. 1-
37、5 1) 2) EIA 411-A b 3234600 0068028 T G/T, is customarily measured at the receiver preamplifier (LNA) output and referred to, the LNA input, It includes the effects of LNA and receiver noise, interconnecting transmission line loss, VSWR, and port-to-port isolation as well as antenna noise. System G/
38、T is independent of reference position. If the operation of the transmitter degrades the G/T, the effects of the transmitter shall be included. 1 e6 ANTEMJA PATTERIO Definition: The antenna pattern is an angular plot of the RF signal strength with respect to the on-axis signal level. NOTE: The signa
39、l level is typically expressed in dB relative to beam peak or dBi. Standard: It shall be standard to specify frequencies, polarization, and angular range of all patterns. In the United States the governing document is FCC Rules + Regulations, Part 25 paragraph 209. Note: Other national and internati
40、onal documents are CCIR 465, INTELSAT Standards for Type A to 2 Earth Station Antennas 1.7 ANTENNA FEED SYSTEM The feed system of an antenna is located at the real or virtual focal point of the antenna and determines primarily a number of antenna characteristics, which are defined in the following s
41、ections. Typically, these parameters are tested and documented in the feed factory. Standard: any feed system as applicable. It shall be standard to specify the following characteristics for . 1-6 - L c EIA q1L-A 86 3234600 0068029 1 W /6 I EIA-411-A 1 a8 FREQUENCY BAND Definition: The frequency ban
42、d is that band or bands of frequencies over which the required performance of the antenna is met. Standard: The frequency band or bands shall be defined by stating lower and upper frequency limits. 1.9 REFLECTION COEPFICIERT, RETURN-LOSS , AND VSWR The reflection coefficient of an antenna system is
43、the ratio of the reflected power to the incident power as measured at the terminals of the antenna system, This is written as Re f lected Power = (Total Incident Power Return Loss is related to Reflection Coefficient by RL = 20 log p. A reflected wave interacts with an incident wave to generate a vo
44、ltage stand- ing wave interference pattern. The ratio of the voltage maximum to voltage minimum in this interference pattern is termed the voltage standing wave ratio VSWR. Reflection Coefficient is related to VSWR by the following rela- t ionship 1.10 PORT-TO-PORT ISOLATION Definition: Isolation is
45、 the ratio of the power level incident in one port to the power level measured in some other port at the same frequency. 1-7 EIA-411-A Standard: The isolation shall be specified. The frequency range over which it is achieved shall be specified. . it is normally expressed in dB, System O isolation in
46、cludes diplexer plus isolation realized through filtering. Tn CP systems it should include the effects of the subreflector and/or main reflector. Method of Measurement: Swept frequency signal source, substitution tech- nique, hard copy recording. 1.11 OHMIC LOSS (INSERTION LOSS) Definition: Ohmic lo
47、ss is that pa,rt of the signal power that is dissipated as heat in the antenna system. Standard: In addition to the losses in the antenna .proper, it shall be standard to include lossee in the transmission line components located between the feed horn and the reference point to which gain, noise tem
48、pera- ture and G/T are referred. Loss is normally expressed in decibels (dB). Method of Measurement: .a e Swept .frequency signal source, substitut ion technique, hardcopy X-Y recording. b, Short-circuit etanding-wave-ratio technique, single frequency recording. Restriction: Measurement methods vali
49、d only for feed network (excluding horn) and associated connecting transmission line to the reference point. i I /Y EIA 4LL-A 6 m 3234600 006803L T m EIA-411-A 1.12 BOURIZATIO Polarization is a property of single-frequency electromagnetic radiation describing the shape and orientation of the locus of the extremity of the field vectors as a function of time. nie far field radiated by an antenna is generally observed in a small region where it can be considered as a plane wave propagating away from the antenna in the radial direction. The electric field is i
