Large-scale active RFID system utilizing ZigBee networks

As the era of the ubiquitous computing is ushered in, consumers have been primed for a variety of automation applications. Active RFIDs can be used for a number of automation applications because it may also have other sensors to extend its applications. An active RFID instinctively focuses on a long communication range. Nevertheless, active RFIDs cannot be applied to a large-scale area due to their limited radio communication and obstacles. This paper introduces a large-scale active RFID system based on multi-hop deployment utilizing dual radio frequency to overcome radio shadow areas that do not reach signals from the RFID reader. The proposed system consists of multiple RFID readers deployed in an ad hoc pattern. It uses a multihop collection scheme utilizing ZigBee networks to extend the coverage of the RFID reader and collect RFID tags outside its communication range. This paper also includes an experiment evaluating performance of the proposed method, using an implemented RFID system that complies with the standard for 433 MHz active RFIDs based on ISO/IEC 18000-7.