An Energy and Application Scenario Aware Active RFID Protocol
1 Centre for Research on Embedded Systems (CERES), Halmstad University, 30118 Halmstad, Sweden
2 Research Department, Free2move AB, 302 48 Halmstad, Sweden
3 Department of Computer Science and Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
EURASIP Journal on Wireless Communications and Networking 2010, 2010:432938 doi:10.1155/2010/432938Published: 8 December 2010
The communication protocol used is a key issue in order to make the most of the advantages of active RFID technologies. In this paper we introduce a carrier sense medium access data communication protocol that dynamically adjusts its back-off algorithm to best suit the actual application at hand. Based on a simulation study of the effect on tag energy cost, read-out delay, and message throughput incurred by some typical back-off algorithms in a CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) active RFID protocol, we conclude that by dynamic tuning of the initial contention window size and back-off interval coefficient, tag energy consumption and read-out delay can be significantly lowered. We show that it is possible to decrease the energy consumption per tag payload delivery with more than 10 times, resulting in a 50% increase in tag battery lifetime. We also discuss the advantage of being able to predict the number of tags present at the RFID-reader as well as ways of doing it.