An analysis of errors in RFID SAW-tag systems with pulse

We analyze the code reading error probability (EP) in the radio frequency identification surface acoustic wave (SAW) tags with pulse position coding (PPC) and peak-pulse detection. EP is found in a most general form assuming M groups of codes with N slots each and allowing individual signal-to-noise ratios (SNRs) in each slot. The basic case of zero signal in all Off-pulses and equal signals in all On-pulses is investigated in detail. We show that if a SAW-tag with PPC is designed such that the spurious responses are attenuated on more than 20 dB below On-pulses, then EP can be achieved at the level of 10-8 (one false per 108 readings) with SNR > 17 dB for any reasonable M and N.