Abstract
Passive surface acoustic wave (SAW) tags require a large signal-to-noise ratio (SNR) in order to increase the interrogation range. For the purpose of achieving high SNR for radio frequency identification (RFID) communication systems, Barker codes, a binary phase shift keying (BPSK) modulation technique, have been adopted in this study. Passive SAW RFID tags were designed with 5-bit Barker code sequences to generate BPSK modulated signals. Through the SNR analysis, the improvements in SNR were about 11 dB using Barker codes along with a correlator, which can be further improved by optimisation in the correlator.
Acknowledgements
This research is supported by the MKE (The Ministry of Knowledge Economy), Korea, under the ITRC (Information Technology Research Center) support program supervised by the NIPA (National IT Industry Promotion Agency) (NIPA-2011-(C1090-1111-0006)) and by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (200921015.01).