Patent ID: 11971473
Assignee: NEC CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A product locating system, comprising:
at least one Radio Frequency (RF) backscatter transmitter configured to emit a main carrier RF signal that forms an excitation signal;
a passive RF backscatter tag associated with a product and configured to generate an Ultra-Wideband (UWB) signal from the excitation signal; and
at least one RF backscatter receiver configured to simultaneously receive both the excitation signal from the at least one RF backscatter transmitter and the UWB signal from the passive RF backscatter tag, and compute a time-difference-of-arrival (TDoA) therebetween;
wherein TDoA information from multiple backscatter receivers, including the at least one RF backscatter receiver, is aggregated to compute the location of the product to which the passive RF backscatter tag is attached;
wherein different RF backscatter transmitters send an excitation signal at different times to activate passive RF backscatter tags in different regions of deployment; and
wherein at least one RF backscatter transmitter first sends a harvesting signal used for energy harvesting by the passive RF scatter tag, followed by a backscatter signal to initiate tag transmission.