Read Bulk Data From Computational RFIDs

Without the need of local energy supply, computational RFID (CRFID) sensors are emerging as important platforms enabling a variety of sensing and computing applications. Nevertheless, the data throughput of CRFIDs is very low. This paper aims at efficiently reading bulk data from CRFIDs using commodity RFID readers. We carry out thorough experiment studies to investigate the root cause of the low data throughput of CRFIDs. The experiment results suggest that the fundamental problem of data transfer stems from the mismatch between the stringent timing requirement of commodity standard and the limited packet handling capability of CRFIDs. We further propose several simple yet effective techniques to allow CRFIDs to meet stringent timing requirement of commodity RFID readers and achieve efficient data transfer. We implement a prototype system based on the WISP CRFIDs and commercial off-the-self RFID readers. We carry out extensive experiments on the prototype systems, which show that the proposed scheme works well with the commodity RFID readers.