Issue link: https://read.uberflip.com/i/1423253
LoRaWAN ™ and LoRa Alliance ™ are marks used under license from the LoRa Alliance ™ www.lora-alliance.org GEOLOCATION WHITEPAPER 5.7 Thorigné-Fouillard (Kerlink/Semtech) Kerlink is offering geolocation-ready stations in its Wirnet IBTS range supporting location-based services (LBS). These new stations provide fine timestamps (using Semtech's license) that can be used for geolocation purposes. A TDOA ranged- based solver has been developed and integrated into a proprietary LBS solution. Kerlink also set up a few test platforms around the world in various environments and conditions (rural area, semi-urban, urban) to assess and optimize the performance of the solver, especially its calculation accuracy and location precision. One testbed is installed at Thorigné-Fouillard (Kerlink HQ) where it operates permanently. Four gateways are installed around the city and several end-devices have been placed in fixed positions. The solver calculates the position as it receives a message in near real-time, and then returns the result to a dashboard for mapping display. Figure 5-17(a) and (b) shows the deployed network and the estimated positions obtained for an end-device. An analysis of HDOP (Figure 5-17(c)) allows us to understand the precision of the results. In addition, its information is used in a Kalman filter for post processing. The CDF, given for this end-device in Figure 5-17(d), shows an accuracy of 32m at 50%, 43m at 70%, and 62m at 90%. Figure 5-17: (a) Thorigné-Fouillard LoRaWAN network testbed (b) estimated positions for a stationary end-device Figure 5-17: (c) HDOP Figure 5-17: (d) CDF