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Can Wireless Carriers Deliver Accurate & Reliable Vertical Location Within The Time Frame ? That Is A Question.”

Founder of IndoorSOS®

FCC Secures 911 Vertical Location Commitments from wireless carriers. However, can they do it now and then in the six-year benchmark time frame? That is a question.

“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.