Patent 9510146 was granted and assigned to CenTrak on November, 2016 by the United States Patent and Trademark Office.
A RTL system and method for operating, the system including: a plurality of groups, each group including: a battery-operated wireless timing beacon generator to transmit timing beacons, wherein the timing beacon generator obtains its timing synchronization for the timing beacons wirelessly from a timing server; and one or more battery-operated secondary technology base-stations to receive the timing beacons, and to transmit respective secondary technology transmissions based on the received timing beacons; and a portable tag to be located, the portable tag configured to receive timing beacons and secondary technology transmissions from at least one group.