We present a promising application of the inverse source technique for antenna diagnostics and the creation of a synthetic higher-performance measurement environment. The focus is on the post-processing of antenna measurements via the recently introduced dual-equation formulation of the inverse source problem, which provides the equivalent sources with highest correlation to actual radiators among the infinite possible choices of equivalence. It is shown how, in practically relevant conditions, measured data can be spatially filtered in the source domain to recover reference conditions not achievable during measurements, e.g., perfectly balanced antenna feeding and absence of supporting structure. The procedure proposed is useful also in the detection, synthetic elimination, and actual correction of the effect of undesired interactions with scatterers in the measurement volume, such as the supporting platform and surrounding obstacles.