Implementation of a Novel, Sparse, Irregular, Multi-Probe Array System for the Rapid Production Test of 5G Massive MIMO Antennas

As the seemingly never-ending desire for ever more data continues, so too does the need for ever more complex antennas operating at ever higher frequencies which are required to satisfy this insatiable demand. This, of course, places greater demands on the associated measurement system with ever increasing acquisition times. Previously, measurement engineers have had the luxury of being able to exhaustively measure these devices, relying upon rigorous but arguably expensive sampling theorems. Unfortunately, in recent years such approaches have become unaffordable. Compressive Sensing (CS) and Sparse Sampling techniques have been applied in a variety of free-field metrology-based applications in an attempt to rein in the amount of data samples required without sacrificing resolution. Recent studies have shown that CS can potentially be used to drastically reduce the number of measurements required to verify antenna array excitations in a demanding time critical production test environment. The process involves a near-field measurement comparison of the test article to that of a ‘gold’ reference antenna under identical test conditions utilizing a total variation strategy. However, this process is sensitive to non-repeatable measurement errors, for example due to mechanical position and RF thermal drift. To combat these errors, a test fixture comprised of an array of fixed RF probes is proposed to rapidly and sparsely sample the nearfield of both a ‘gold’ reference and ensuing test articles for the purpose of very quickly identifying array failures in a production facility.