1990 Technical Papers

A Millimeter Compact Range

Authors: James D. Huff, Christopher B. Brechin

Publication: AMTA 1990

Copyright Owner: NSI-MI Technologies

The compact range mechanically collimates electro-magnetic energy, thus creating a plane wave useful for testing antennas in a far field environment. Since this collimation can be achieved in a relatively small space, the tests can be performed in an environmentally controlled chamber. With the increasing use in both military and commercial applications of antennas operating at millimeter wavelengths, there is increasing need for small compact ranges operating in the 26.5 to 100 GHz frequency range. This paper describes the development of a small compact range with a two foot diameter test zone that operates from 26.5 GHz to greater than 100 GHz.

High Speed Measurements of T-R Modules

Authors: John R. Jones, Curtis E. Green

Publication: AMTA 1990

Copyright Owner: NSI-MI Technologies

An s-parameter measurement system and a procedure are described for making fast s-parameter measurements on multi-state devices. A sample test problem is considered and the application of the system and the procedure to this test problem is discussed. The important features of the system are described and timing measurements of system operation are presented.

Productivity Improvements for a Gated-CW RADAR

Authors: J. B. Wilson

Publication: AMTA 1990

Copyright Owner: NSI-MI Technologies

This paper will describe new developments in a gated-CW radar that has been designed to improve the productivity and sensitivity of RCS measurements. Improvement in data acquisition speeds result from the design of a fast synthesizer, a data acquisition co-processor and pulse modulator. Each of these new products have been specifically designed to take advantage of the high speed capabilities of Scientific-Atlanta’s Model 1795 Microwave Receiver. The RF sub-system has also been designed to permit continuous 2-18 GHz, full polarization data acquisitions. Critical RF components are now mounted at the feed in the chamber, improving the sensitivity and ringdown of the the system. Productivity in analysis activities has been improved by the use of a multi-tasking system controller which permits simultaneous use of the system for acquisitions, analysis, and plotting.

The Effects of Non-Systematic Instrumentation Errors on Measurement Uncertainty

Author: 0. M. Caldwell

Publication: AMTA 1990

Copyright Owner: NSI-MI Technologies

The effects of non-systematic receiver instrumentation errors on precision antenna measurements are investigated. A simple uncertainty model relating dynamic range to random perturbation effects on amplitude measurements is proposed. Examples of measurement uncertainty versus both input level and measurement speed are presented using data taken on modern measurement receivers. Data are compared w1th the model to estimate measurement uncertainty at various pattern levels and acquisition speeds. Equivalent dynamic range specifications are deduced from the measured data.

An Overview of Parameters Determining Productivity and Sensitivity in RCS Measurement Facilities

Authors: Edward B. Hart, William G. Luehrs

Publication: AMTA 1990

Copyright Owner: NSI-MI Technologies

A major objective in the design of an RCS measurement facility is to obtain the greatest possible productivity (overall measurement efficiency) while maintaining the accuracy and sensitivity necessary for low radar cross section targets. This paper will present parameters affecting the total throughput rates of an indoor facility including instrumentation, target handling, and band changes - one of the most time consuming activities in the measurement process. Sensitivity and accuracy issues to be discussed include radar capabilities, feeds and feed clustering, compact range, background levels, and diffraction control.

An Overview of Parameters Determining Productivity and Sensitivity in RCS Measurement Facilities

Authors: Edward B. Hart, William G. Luehrs

Publication: AMTA 1990

Copyright Owner: NSI-MI Technologies

A major objective in the design of an RCS measurement facility is to obtain the greatest possible productivity (overall measurement efficiency) while maintaining the accuracy and sensitivity necessary for low radar cross section targets. This paper will present parameters affecting the total throughput rates of an indoor facility including instrumentation, target handling, and band changes - one of the most time consuming activities in the measurement process. Sensitivity and accuracy issues to be discussed include radar capabilities, feeds and feed clustering, compact range, background levels, and diffraction control.

Longitudinal Translation at Selected Points a Measured Technique Revisited

Author: Doren W. Hess

Publication: AMTA 1990

Copyright Owner: NSI-MI Technologies

The extraneous signals that perturb antenna patterns can be found and identified by a method known as "longitudinal translation at selected points". The method is usually applied to certain selected angular points on the antenna pattern. With this technique the composite pattern -- consisting of the direct-path signal and the reflection signal -- is measured at a series of translation distances along the axis of the antenna range. By utilizing both the amplitude and phase of the received signal, one can remove the signal that results from stray reflection and retain the desired direct path signal. The result is an improved and more accurate version of the pattern. In this presentation I review this technique as specifically applied to compact range antenna measurements, and apply it to several patterns, to demonstrate the method.

1
2

Atlanta

1125 Satellite Blvd. NW,
Ste. 100
Suwanee, GA 30024 USA

+1 678 475 8300
+1 678 542 2601

Los Angeles

19730 Magellan Dr.
Torrance, CA 90502 USA

+1 310 525 7000
+1 310 525 7100

NSI-MI UK

C/O AMETEK LAND,
Stubley Lane,
Dronfield, S18 1DJ UK

+44 1246 581500

MRO Americas

Atlanta, GA Finding your local time... 16 Days mroamericas.aviationweek.com