US 12,216,219 B2
Radio frequency (RF) ranging in propagation limited RF environments utilizing aerial vehicles
David Farrell, Loveland, CO (US); and Thomas Pattison, Kamuela, HI (US)
Assigned to RTR Technologies, Inc., Loveland, CO (US)
Filed by RTR Technologies, Inc, Loveland, CO (US)
Filed on Mar. 1, 2024, as Appl. No. 18/592,686.
Application 18/592,686 is a continuation of application No. 18/199,934, filed on May 20, 2023, granted, now 11,971,492.
Application 18/199,934 is a continuation of application No. 17/584,117, filed on Jan. 25, 2022, granted, now 11,693,127, issued on Jul. 4, 2023.
Application 17/584,117 is a continuation of application No. 16/875,501, filed on May 15, 2020, granted, now 11,275,181, issued on Mar. 15, 2022.
Claims priority of provisional application 62/847,992, filed on May 15, 2019.
Prior Publication US 2024/0201398 A1, Jun. 20, 2024
Int. Cl. G01S 19/46 (2010.01); G01S 19/11 (2010.01); G01S 19/51 (2010.01)
CPC G01S 19/46 (2013.01) [G01S 19/115 (2019.08); G01S 19/51 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A ranging system, comprising:
transponders mounted to unmanned aerial vehicles; and
a range detector configured to determine first GPS coordinates of a first unmanned aerial vehicle when hovering proximate to a first known location, and to determine second GPS coordinates of a second unmanned aerial vehicle when hovering proximate to a second known location;
for each transponder of the transponders mounted to the first unmanned aerial vehicle and the second unmanned aerial vehicle, the range detector is further configured to calculate a distance between the range detector and the transponder based on Radio Frequency (RF) signals exchanged with the transponder;
the range detector is further configured to calculate a position of the range detector relative to the first known location and the second known location based on the distance calculated between the range detector and the transponder mounted to the first unmanned aerial vehicle, a distance between the first GPS coordinates and the first known location, the distance calculated between the range detector and the transponder mounted to the second unmanned aerial vehicle, a distance between the second GPS coordinates and the second known location, a distance between the first GPS coordinates and the second GPS coordinates, and a distance between the first known location and the second known location.