Transient phased array distortion measurements

As a beam is steered on a phased array system, the transients of the beam itself may be of interest for analyzing settling, system response times and other factors. The transient behavior of distortion products can also be of interest for similar reasons. In addition, the angle of distortion products may deviate significantly from that of the main beam due to simple array calibration differences or due to array nonlinear effects. These differences and the potential for more substantive transient behavior from individual element nonlinearities settling and interacting can make system performance implications interesting. This work explores a wideband vector network analyzer (VNA)-based measurement structure that allows for transient time resolution into the ns range for some configurations, synchronization of product measurements, and enough dynamic range (often > 90 dB at >28 GHz) that useful distortion product measurements can be obtained for microwave and mm-wave arrays.