A Gaussian-Process-Interpolation-Model-Based Approach for Robust, Independent, and Implementation-Agnostic Validation of Complex Multi-Variable Measurement Systems: Application to SAR Measurement Systems

Resource-efficient and robust validation of complex measurement system that would require millions of test permutations for comprehensive coverage is an unsolved problem. In the paper, a general, robust, trustworthy, efficient, and comprehensive validation approach based on a Gaussian Process Interpolation (GPI)-model of the test-system has been developed that can operate system-agnostically, prevents calibration to known validation benchmarks, and supports large configuration spaces. The approach includes three steps that can be performed independently by different parties: 1) GPI-model creation, 2) model confirmation, and 3) model-based critical search for failures. The new apporach has been applied to two systems utilizing different measurement methods, i.e., robot-scanning and fixed sensor array, for compliance testing of radiofrequency-emitting devices with the objective to demonstrate validity and equivalence of the two systems. The result demonstrate that measurement system validation is feasible within a single day by a test-lab or the user. It has been proposed to the standardization committees as a proposal to unify and strengthen the current IEC 62209-1528 and IEC 62209-3 standards, resulting in a pragmatic approach for establishing validity and effective equivalence of the two measurement device classes.