Near-field range assessment

The uncertainty concepts described in this chapter form the basis of any range assessment (RA), regardless of the type of test facility and therefore allow us to create a framework within which the quality of any antenna measurement result can be expressed. It also allows us to do meaningful range inter-comparisons that have become such an integral part of modern test programmes. Although most of the groundwork related to RAs was conducted in an effort to validate near-field testing in the early days, this work has found wider application and can today be applied to far-field and CATR test systems with equal success. It is safe to say that the antenna measurement community (for the most part) have adopted the principle that measurement results need to be reported with an associated uncertainty, to make them credible.Finally, a very welcome side effect of doing any RA is a greater understanding of the measurement process and associated weaknesses. This often leads to a clear definition of exactly what aspect needs to be addressed if uncertainty is to be reduced, making for a very efficient use of resources in the process.