Nasa's Horizontal Planar Near-Field Facility: A Large-Scale, High-Accuracy System for Spaceborne Antenna Testing

NASA has commissioned a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{1 0 m} \boldsymbol{\times} \mathbf{1 0 m}$</tex> Horizontal Planar Near-Field (HPNF) measurement facility to advance the precision characterization of spaceborne antennas for aerospace and defense applications. Developed by MVG-OATI and NASA Glenn Research Center, the system accommodates diverse antenna types, including active electronically scanned arrays (AESAs) and parabolic reflectors, across a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{1-110 ~ GHz}$</tex> frequency range. It employs planar near-field techniques to measure gain, directivity, 3D radiation patterns, sidelobe levels, and advanced metrics like effective isotropic radiated power (EIRP), gain-to-noise-temperature (G/T), intermodulation distortion (IMD), and gain compression. The horizontal orientation simplifies installation and mitigates gravity-induced distortions, critical for zero-gravity space environments. A laser tracker ensures precise alignment and surface measurements, enhancing millimeter-wave accuracy. This paper provides an overview of the facility's design, measurement methodology, and preliminary performance, highlighting its role in next-generation antenna testing.