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Generalized Probe-Position Compensation Methods for Near-Field Antenna Measurements



Michael H. Francis, Ronald C. Wittmann, Josh Gordon, David R. Novotny


The National Institute of Standards and Technology (NIST) has developed computationally efficient algorithms for probe location and polarization compensation in near- to far-field transformations for use when measurements are not made on the standard canonical grids. A major application of such methods is at higher frequencies, where it is difficult or impractical to locate a probe to required tolerances for the standard transforms. Our algorithms require knowledge of the actual position of the probe at the measurement points. This information can be furnished by state-of-the-art optical tracking devices. Probe position information is routinely obtained by the NIST CROMMA (Configurable Robotic MilliMeter-wave Antenna) Facility. Even at lower frequencies, probe-location compensation techniques allow in principle, the use of less precise and therefore, less expensive scanning hardware. Our approach also provides the flexibility to process data intentionally collected on nonstandard grids (plane-polar, spiral, etc.) or with mixed geometries (such as a cylinder with a hemispherical or planar end cap). We present actual probe position compensation results at 183 GHz. The possibility of compensating for known variations in the probe pointing is considered.
Proceedings Title
Proceedings of the Antenna Measurement Techniques Association
Conference Dates
October 11-16, 2015
Conference Location
Long Beach, CA, US


antenna measurements, near-field measurements, probe position compensation, spherical scanning


Francis, M. , Wittmann, R. , Gordon, J. and Novotny, D. (2015), Generalized Probe-Position Compensation Methods for Near-Field Antenna Measurements, Proceedings of the Antenna Measurement Techniques Association, Long Beach, CA, US, [online], (Accessed May 24, 2024)


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Created October 10, 2015, Updated April 12, 2022