Pseudo-random Aloha for Enhanced Collision-recovery in RFID

TL;DR

This paper proposes a pseudo-random Aloha protocol for RFID systems that enhances collision recovery at the PHY layer, leading to significant throughput improvements without altering existing standards.

Contribution

It introduces a deterministic slot selection method enabling collision recovery techniques like ISIC in RFID MAC protocols, improving throughput over traditional methods.

Findings

20-25% throughput gain with ISIC

Pseudo-random access enables collision recovery without changing PHY standards

Potential for combining pseudo-random protocols with advanced PHY techniques

Abstract

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 to consider a simple variant of the Framed Slotted Aloha with pseudo-random (deterministic) slot selection as opposite to the classical random selection. Pseudo-random access allows naturally to implement 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-frame SIC. Besides that, we elaborate on the potential of leveraging pseudo-random access protocols in combination with advanced PHY techniques in the context of RFID applications.