Founder of IndoorSOS®
“2021 April 3, 2021 (Six-year benchmark)*Horizontal Location Accuracy Benchmark: Nationwide providers must achieve 50-meter horizontal accuracy (x/y location within 50 meters) or provide the dispatchable location for 80% of all wireless 911 calls. (47 CFR § 9.10(i)(2)(i)(A)(4)) Non-nationwide providers must achieve the 80 % call threshold described above by this date or within one year of the provider’s deployment of a commercially operating VoLTE platform in the provider’s network, whichever is later. (47 CFR § 9.10(i)(2)(i)(B)(4))” Vertical Location Accuracy Benchmark: In each of the top 25 cellular market areas (CMAs), nationwide CMRS providers shall deploy either dispatchable location or z-axis technology. (47 CFR § 9.10(i)(2)(ii)(C)) Because it is dependent on a technological breakthrough. Currently, the two vertical location technology vendors of NextNav, and Polaris Wireless, are primarily using Barometric Pressure based-Z tech referencing HAE data converted into vertical height information of a building. While NextNav uses Barometric Pressure based-Z with support by the Metropolitan Beacon System (MBS), Polaris Wireless uses Barometric Pressure based Z, and Hybrid X.Y. consisting of U.E. -User-Equipment-based GPS, UE-Assisted GPS, ECID (Exclusive Chip Identification of iPhone), Barometer, WiFi access point).
Neither methodology produces floor-level identity that PSAP and first responders can rely on for action without a doubt. The Stage Z Test Report presented several unanswered questions regarding real-world performance, including the accuracy and yield of z-axis information. See Stage Z Test Report pp. 121-22. “While the results of the testing provide valuable data and lessons learned, numerous key questions remain unanswered through the Stage Z testing:
How would a barometric pressure-based altitude estimation technology perform in a real-world production deployment (integrated into a wireless network and a commercial mobile device in normal use).
What yield (or availability) to expect in a real-world production deployment.
What latency to expect in a real-world production deployment.
How a barometric pressure-based altitude estimation system would scale from a small handful of individually calibrated test handsets (six per region in the initial Test Bed) to hundreds of millions of devices across the U.S.
How one-time manual calibration would perform on an iOS device.
How Z-Axis accuracy degrades with the age of the barometer, as barometer manufacturers have indicated that accuracy degrades as the sensors age (i.e., from the Page 121 9-1-1 Location Technologies Test Bed, LLC Stage Z Report time of manufacture of the mobile device) though no test handsets over 1.5 years old were included in this initial Test Bed campaign.
How Z-Axis accuracy degrades with lower-end devices.
The performance of devices with active mobile device barometric sensor bias calibration in rural morphologies, in very cold weather, and in high winds.
The extent to which individual barometer bias in a given handset can be adequately calibrated out of the altitude estimate in a standardized production environment once integrated into a wireless carrier’s network and with mobile devices in normal use. How barometer bias for a given sensor varies over time and other factors, and how frequently the sensor needs to be calibrated to effectively manage errors.
The extent to which, and how, altitude could be accurately converted into building floor level for pressure-based estimation systems. Before further research and testing, a technology feasibility study might be the first step.
The extent to which the accuracy of the barometer reading is affected by an active call on the mobile device.”
IndoorSOS® is ready to introduce its ‘On-premises & U.E. Based Indoor Location Tech’ that provides reliable vertical data of floor level id, meter grade accuracy horizontal positioning, and sustains supporting in-building power outage and internet interruption.