A method includes: transmitting, from a reader device, a first set of wireless signals, in a first frequency band, detectable by RFID transponder devices; transmitting, from the reader device, a second set of wireless signals, at a second frequency band different from the first frequency band, detectable by the RFID transponder devices; detecting, at the reader device, a set of reply wireless signals transmitted by one or more of the RFID transponder devices in response to the first set of wireless signals, the set of reply signals comprising identification data associated with the one or more of the RFID transponder devices, and orientation information representative of relative orientation of the respective one or more of the RFID transponder devices to the reader device; and deriving location information for at least one of the one or more of the RFID transponder devices based on the detected set of reply wireless signals.