2007 Technical Papers

Planar and Spherical Near-Field Range Comparison with -60 dB Residual Error Level

Authors: Allen Newell, Greg Hindman
Publication: AMTA 2007
Copyright Owner: NSI-MI Technologies

Comparisons of the far-field results from two different ranges are a useful complement to the detailed 18 term uncertainty analysis procedure. Such comparisons can verify that the individual estimates of uncertainty for each range are reliable or indicate whether they are either too conservative or too optimistic. Such a comparison has recently been completed using planar and spherical nearfield ranges at Nearfield Systems Inc. The test antenna was a mechanically and electrically stable slotted waveguide array with relatively low side lobes and cross polarization and a gain of approximately 35 dBi.

The accuracies of both ranges were improved by testing for, and where appropriate, applying small corrections to the measured data for some of the individual 18 terms. The corrections reduce, but do not eliminate the errors for the selected terms and do not change the basic near-to-far field transformations or probe correction processes. The corrections considered were for bias error leakage, multiple reflections, rotary joint variations and spherical range alignment. Room scattering for the spherical measurements was evaluated using the MARS processing developed by NSI.

The final results showed a peak equivalent error signal level in the side lobe region of approximately -60 dB for both main and cross component patterns for angles of up to 80 degrees off-axis.


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


Stubley Lane,
Dronfield, S18 1DJ UK

+44 1246 581500


Seattle, WA Finding your local time... 15 Days 2023.amta.org
This site is using cookies for analytical purposes and to provide a better user experience. Read our Privacy Policy for more information.