Approaches to Wireless E9-1-1 Indoor Location Performance Testing
|Publication Date:||1 February 2010|
This document presents guidelines for assessing the performance of wireless location technologies in various types of indoor structures and indoor calling scenarios. This document is separate and distinct from ATIS-0500001 "High Level Requirements for Accuracy Testing Methodologies". ATIS-0500001 provides guidelines for testing E911 wireless location technologies for compliance with the E911 Phase II FCC-mandated location accuracy requirements outlined in FCC Docket 94-102, Third Report and Order. Performance testing differs from accuracy testing for compliance in that:
♦ Performance testing is optional and is conducted to provide information for use in the decision making process such as planning network configurations or developing dispatcher training in certain emergency response situations.
♦ Accuracy testing for compliance is mandatory and is conducted to measure the wireless E911 Phase II location technology against specific FCC-mandated accuracy requirements.
The guidelines in this indoor performance measurement document provide an overview of the indoor testing process and walk the user through:
♦ The establishment of indoor test scenarios and locations,
♦ The creation of a plan for the selection of test sites,
♦ The establishment of an accurate ground truth at each test site,
♦ The field testing and data collection,
♦ The analysis of results and ground truth verification, and
♦ Understanding performance test results.
The purpose of this document is to provide optional guidelines for a user to assess indoor location performance within different types of permanent structures and from different call locations within a given structure.
Indoor testing is distinct from outdoor testing in that location performance can vary greatly depending on the composition of the structure, the composition and density of the surrounding structures, and the placement of the call within the given structure (e.g., near a window or door or deep within structure's core). The test sites within the building need to be chosen in order to provide a true representation of the type of structure and how it is used by the public, whereas accuracy compliance outdoor testing is dependent on the random selection of test sites that together provide a valid representation of the test area and statistical independence of test results. Also, indoor location performance testing has challenges associated with gaining access to structures in order to make test calls.
With any location testing the acquisition of an accurate ground truth at each test site is critical. Test results cannot be considered valid unless the users of the data are assured that consistent, accurate ground truth has been established for each site in the test plan. With indoor testing, the establishment of an accurate ground truth is often challenging due to blockage of GPS signals and complexity of alternative ground truth measurement methods. This document provides in depth guidance on the various methods for acquiring indoor ground truth and techniques to ensure that the ground truth for each test site is accurate.