Measurement procedures for design and enforcement of harm claim thresholds

Abstract

Harm claim thresholds (HCTs) are a promising approach for regulators to specify interference limits in a technology-neutral fashion, and a useful parameter spectrum access systems can use to manage the aggregate interference caused by transmitters they control. However, existing literature provides very little guidance how HCTs should be set and enforced. In this paper we propose a detailed regulatory framework for gathering and processing of measurement data for enforcing and setting harm claim thresholds. We introduce the central concepts of stratification and weighting of measurement data, and show their importance in ensuring representativeness of measurements and enabling robust estimation of statistical confidence on results. For deriving HCT thresholds from measurements, we propose additional representativeness criteria that a regulator should apply to avoid underestimation of field strength levels related to existing wireless services. We demonstrate application of our proposed framework using an extensive drive test data set, and show that the chosen HCT percentile is critical in determining how much data needs to be gathered for enforcement. We also discuss the various design choices and parameters needed by our framework, and show through examples how they can be derived in cooperation with the different stakeholders. The developed framework has several applications beyond HCT enforcement, some of which are briefly described in the paper.