A cylindrical near-field vs. spherical near-field - antenna test comparison

A new series of spherical near-field probe positioning devices has been designed and constructed, consisting of a large 5.0 m 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.