Pseudo-Random ALOHA for Enhanced Collision-Recovery in RFID

In this letter we motivate the need to revisit the MAC protocol used in Gen2 RFID system in order to leverage receiver structures with Collision Recovery capabilities at the PHY layer. To this end we propose a simple variant of the Framed Slotted-ALOHA where slot selection is not random, as in the classical scheme, but instead computed deterministically by a pseudo-random function of the message to be transmitted and the frame index. Deterministic slot selection enables Inter-frame Successive Interference Cancellation (ISIC) without changing the PHY modulation and coding format of legacy RFID standard. By means of simulations we show that ISIC can bring 20-25% gain in throughput with respect to traditional intra-slot SIC.