Improving the read range of RFID sensors

Active RFID sensors are increasingly replacing their wired counterparts. However, their need for batteries, high unit costs and vulnerability to harsh environmental conditions (i.e., vibration, shock, temperature) make the passive RFIDs a favored option, even if they are associated with shorter distance detections. In addition to their limited read range, current passive sensor tags are relatively large for tagging small objects, including many commercial products where bar codes are currently the norm. Also, reader systems associated with off-the-shelf passive RFID sensors are comparatively expensive. In this paper, we propose an alternative for both of these problems.