Portable Freehand System for Real-Time Antenna Diagnosis and Characterization

This article presents an agile system for antenna diagnosis. The system is operated by means of freehand movements of the probe antenna avoiding the need of bulky positioners and thus providing portability to the system. For that purpose, the probe antenna position, which is required by the antenna diagnosis algorithm, is retrieved by means of an affordable and quickly deployable motion capture system. The probe position and the acquired field are used to characterize the antenna under test by computing an equivalent currents distribution on the antenna aperture and its far-field pattern in real-time. To achieve that, an ad hoc workflow is designed including a method for spatially balancing the acquired field samples. Although the system is not intended to provide an accuracy comparable to the one achieved by anechoic chamber facilities, it opens a new horizon of possibilities for in situ agile characterization of antennas enabling the detection of faulty elements or radiation pattern deviations. Results at Ku - and Ka -bands, supported by attached multimedia material, are presented to illustrate the capabilities of the system.