At the recent IDTechEx conference Wireless Sensor Networks and RTLS Europe in Munich, Colin Faulkner of the UK fabless semiconductor company Jennic spoke on Active RFID Applications Using IEEE 802.15.4. These are strong candidates for energy harvesting. He described their capability and illustrated this with tags having low power consumption when not transmitting data – less than 2uA of current. They use broadcast data transmissions to pass data to local reader(s). They do not associate or join the network of readers and are therefore completely mobile. They transmit a unique 64-bit ID and battery voltage and temperature are measured using the on chip temperature sensor. Taking the sequence number and number of CCA failures, performance statistics can be calculated. He described potential use in container trucking, care for the elderly, retailing etc. The Jennic JenNet proprietary network permits star tree and linear topologies.
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