Over-the-Air Testing for Connecting Faults Diagnosis in Beamforming Antenna Arrays with Short Measurement Distance

A novel diagnosis method for detecting the connecting faults (i.e., disconnected and misconnected antenna elements) in beamforming antenna array is proposed. Compared with state-of-the-art methods, the proposed diagnosis method can be conducted when the phased array operates in its default beam-steering mode. Moreover, the proposed diagnosis method is fast since it only requires a few near-field measurement positions in a very short distance (i.e., the near-field of the array). Measurement uncertainties, e.g., the scatterings from the practical testing environment, are considered in the method. Therefore, the proposed method can robustly detect beamforming array connecting faults in practical production line testing environments. The method is first validated using an 11-element dual-polarized base station (BS) antenna array at 2.7 GHz by numerical simulations. It is further experimentally validated using an eight-element single-polarized patch antenna array at 3.6 GHz. The same antenna array also serves as the probe array with only a 10-cm distance between the antenna under test (AUT) and the probe array. The diagnosis results for different types of connecting faults with numerical simulations and measurement validations have verified the effectiveness and robustness of the proposed method in practical applications.