Basic Rules for Anechoic Chamber Design, Part Two: Compact Ranges and Near Field Measurements

Author: Vince Rodriguez
Publication: Microwave Journal

The task of adequately specifying performance for an indoor anechoic chamber without driving unnecessary costs or specifying contradictory requirements calls for insight that is not always available to the author of the specification. Although there are some articles and books13 that address anechoic chamber design, a concise compendium of reference information and rules of thumb on the subject would be useful. This second part of the series intends to do that, concentrating on the sizing of compact ranges and chambers for near field systems. As was done in part one, simple approximations are used for absorber performance to generate a series of equations that help specify performance and size of facilities.

 

Basic Rules for Anechoic Chamber Design, Part One: RF Absorber Approximations

Author: Vince Rodriguez
Publication: Microwave Journal

The task of adequately specifying performance for an indoor anechoic chamber without driving unnecessary costs or specifying contradictory requirements calls for insight that is not always available to the author of the specification. While there are some articles and books13 that address anechoic chamber design, a concise compendium of reference information and rules of thumb on the subject would be useful. This article intends to be a helpful tool in that regard. It starts by recommending the proper type of range for different antenna types and frequencies of operation. Rules of thumb are provided to select the best approach for the required test or antenna type. The article concentrates on rectangular chambers. Simple approximations are used for absorber performance to generate a series of charts that can be used as a guide to specify performance and appropriate facility size.

 

Telematic Antenna Testing

Authors: Dr. Donald G. Bodnar, Dr. Daniel N. Aloi
Publication: Electronic Component News (ECN) Magazine

Today’s automobiles have a wide variety of RF systems with antennas on them for Sirius and XM radio, collision avoidance radars, the Global Positioning System (GPS) and other systems. Conventional test facilities can only perform terrestrial directed pattern measurements of the antenna on the automobile. Special test facilities are required when the automobile must communicate with a satellite as well as other ground systems. Table 1 provides a partial list of satellite-based wireless systems below 2.5 GHz in frequency. This paper discusses a system specially designed for making antenna measurements from the zenith to the horizon. In addition, some of the issues involved in making satellite band measurements such as Sirius/XM and GPS and terrestrial band measurements such as CELL800 and CELL1800 are reviewed.

 

The IsoFilterTM Technique: A Method of Isolating the Pattern of an Individual Radiator from Data Measured in a Contaminated Environment

Author: Doren W. Hess
Publication: IEEE Antennas and Propagation Magazine

This paper describes a novel method, termed the IsofilterTM Technique, of isolating in the measured data the radiation pattern of an individual radiator from among a composite set of radiators that form a complex radiation distribution. This technique proceeds via three successive steps: A spherical NFFF transform on an oversampled data set, followed by a change of coordinate system followed in turn by filtering in the domain of the spherical modes to isolate a radiating source. The end result is to yield an approximate pattern of the individual radiator largely uncontaminated by the other competing sources of radiation.

You have requested a Reprint of an IEEE Paper

Copyright 2010 IEEE.

This material is posted here with permission of the IEEE. Such permission of the IEEE does not in any way imply IEEE endorsement of any of NSI-MI Technologies' products or services. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to pubs-permissions@ieee.org.

By choosing to view this document, you agree to all provisions of the copyright laws protecting it


Military Radome Performance and Verification Testing

Author: Thomas B. Darling
Publication: Microwave Products Digest

Incredible efforts are made by system designers to produce state-of-the-art radar and other RF based capabilities for our military. Modern radar systems are used for various purposes including, but not limited to: weather assessment; navigation; terrain following/terrain avoidance; weapons fire control; electronic warfare; enemy tracking, listening and identification, etc.

 

RCS Measurements in a Compact Range

Author: Jeff Fordham, Marion Baggett
Publication: Microwave Products Digest

The Radar Cross Section (RCS) of an object is defined as, “the area intercepting that amount of power which, when scattered isotropically, produces a return at the radar equal to that from the target.” In simpler terms, RCS is the projected area of a sphere that has the same radar return as the target. The unit of measure for an object’s RCS is “decibels per square meter,” or dBsm. The power received by a radar for a target indicates how well the radar can detect or track that target. For this reason, much research and effort has been put into reducing the “signature” of various aircraft, ships and other objects.

 

A Cylindrical Near-Field vs. Spherical Near-Field Antenna Test Comparison

Author: Jeffrey Fordham
Publication: Base Station Earth Station

A new series of spherical near-field probe positioning devices has been designed and constructed consisting of a large 5.0 meter fixed arc. Several of these large radius arc systems have been developed for telematic antenna testing, radar antenna and ground based communication systems test.

As part of the delivery of one of these spherical near-field (SNF) test systems, a measurement study was performed to determine the accuracy of the new facility relative to an existing cylindrical near-field (CNF) test facility. The study was conducted by collecting and processing data on an offset fed parabola reflector antenna both on the CNF range and on the SNF antenna test range.

This article summarizes the results obtained as part of the measurement program and includes discussions on the error budgets for the two ranges along with a discussion on the mutual error budget between the two ranges.

 
  • 1
  • 2

Atlanta

1125 Satellite Blvd., Suite 100
Suwanee, GA 30024-4629 USA

+1 678 475 8300
+1 678 542 2601
sales@nsi-mi.com

Los Angeles

19730 Magellan Drive
Torrance, CA 90502-1104 USA

+1 310 525 7000
+1 310 525 7100
sales@nsi-mi.com

TU-Automotive

Novi, MI 06/06/2018 09:00 am 11 Days