scope:

Current standards define several two-dimensional and three-dimensional shapes and numerous reporting formats with varying underlying assumptions and approaches for capturing the wireless location estimate with its uncertainty bounds and confidence. These varying approaches to reporting two-dimensional and three-dimensional shapes have the potential to cause confusion and introduce additional errors, particularly as the shapes propagate between components in a broader positioning system from wireless network to PSAP. Furthermore, these varying representation approaches can cause confusion when testing location solutions, potentially impairing test results. This Technical Report presents the results of a survey of the existing standards related to location reporting shapes along with recommendations.

Purpose

In addition to surveying the related standards where reporting formats are defined, identifying common features and potential gaps, this Technical Report makes recommendations for reporting two-dimensional and threedimensional shapes and best practices for propagating the shapes to minimize the accumulation of errors. It also makes recommendations for performing the minimum number of position estimate shapes conversion between elements in the end-to-end location system, where different standards may be used.

Detailed discussion of the entities responsible for performing shapes conversion under various network interconnection architectures is outside the scope of this document.