Z. Huang et al., "A Novel Cross Layer Anti-Collision Algorithm for Slotted ALOHA-Based UHF RFID Systems," in IEEE Access, vol. 7, pp. 36207-36217, 2019. doi: 10.1109/ACCESS.2019.2900739
Reducing collisions in UHF RFID systems is a crucial problem. In most anti-collision designs,
the reader has to estimate the number of tags within its reading range during the interrogation process. Most
of the approaches estimate the number of tags with observations in multiple time slots. Since estimation error
varies along with the initial frame length and the number of tags, system ef ciency is affected by both of them.
To reduce the sensitiveness to them and improve system ef ciency, we propose a novel MAC-PHY crosslayer
anti-collision algorithm based on Bayesian inference. Speci cally, each frame is allowed to end at an
early stage and a slot-by-slot estimator is proposed. Bene t from its slot-by-slot nature, system ef ciency is
more stable and independent on the initial frame length and very close to the upper bound of dynamic framed
slotted ALOHA (DFSA) algorithm. The performance of the proposed method is compared with the stateof-
the-art algorithms through numeric simulations. The results show that the proposed solution signi cantly
outperforms the compared ones.