A Field Test for Phaseless Measurements for Nearfield Inspections of Navigation Systems with UAVs

In this contribution results are presented for phase and amplitude measurements of antennas without any carrier synchronization. This investigation is part of the NAVANT project, that deals with near field measurements of navigation systems by means of unmanned aerial vehicle. A necessary precondition for performing such measurements is a sufficient accuracy of the phase, which usually is done with a network analyzer. However, since antennas under test are not accessible with respect to the feed, phase measurements must be done without carrier synchronization, requiring a different measurement concept, which is validated by first field tests described in this contribution with a corresponding setup at an open area test site. As a result, the phase accuracy turns out to be sufficiently accurate at VHF frequency with a maximum error of smaller than 3°.