Patent ID: 11907779
Assignee: SENSORMATIC ELECTRONICS, LLC
Field: Computer technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 14:
15. A radio-frequency (RF) identification (RFID) system, comprising:
a signal generator configured for generating a modulating signal; and
an RF mixer configured for modulating a first RF signal with the modulating signal to provide a modulated signal,
wherein the first RF signal has an RF carrier frequency according to an RFID protocol,
wherein the signal generator provides the first RF signal to a main directional antenna in the RFID system to radiate a first signal toward a first main lobe of the main directional antenna for reading one or more RFID tags according to the RFID protocol,
wherein the first RF signal further causes the main directional antenna to radiate an unintended signal toward a side-lobe of the main directional antenna,
wherein the RF mixer is further configured to provide the modulated signal to a secondary directional antenna installed back to back with the main directional antenna and having a second main lobe extending in a same direction as the side-lobe of the main directional antenna to radiate a second signal toward the second main lobe of the secondary directional antenna to reduce or prevent a reading of one or more stray RFID tags by the RFID system due to the unintended signal.