Methods and systems for rfid tag geographical location using beacon tags and listening tags

Abstract

RFID method and system are provided. A reader transmits a reader signal to beacon tags and a listening tag. The beacon tags transmit beacon signals including a beacon identification and a beacon distance to the reader. The listening tag receives the beacon signals. Neighbor distances are calculated for the beacon tags based on when the beacon signals are received, when the listening tag receives the reader signal, and a constant processing time. The neighbor distances are the individual distances from the listening tag to the beacon tags. A list is stored including the beacon identification for the beacon tags, the beacon distance, and the neighbor distances. The listening tag transmits the list and a listening tag identification to the reader. A geographical position of the listening tag is calculated based on the beacon distance, beacon coordinates, and a listening tag distance which is from the reader to the listening tag.