RFID Anticollision in Dense Mobile Environments

Abstract

The popularization of RFID systems has conducted to large deployments of RFID solutions in various areas under different criteria. However, such deployments, specially in dense environments, can be subject to RFID collisions which in turn affect the quality of readings. In this paper we propose two distributed and efficient solutions for dense mobile deployments of RFID systems. mDEFAR is an adaptation of a previous work highly performing in terms of collisions reduction, efficiency and fairness in dense static deployments. CORA is more of a locally mutual solution where each reader relies on its neighborhood to enable itself or not. Using a beaconing mechanism, each reader is able to identify potential (non-)colliding neighbors in a running frame and as such chooses to read or not. Performance evaluation shows high performance in terms of coverage delay for both proposals quickly achieving 100% coverage depending on the considered use case while always maintaining consistent efficiency levels above 70%. Compared to GDRA, our solutions proved to be better suited for highly dense and mobile environments, offering both higher throughput and efficiency. The results reveal that depending on the application considered, choosing either mDEFAR or CORA helps improve efficiency and coverage delay.

DACAR: Distributed & Adaptable Crosslayer Anticollision and Routing Protocol for RFID

“…We implemented DACAR using two anti-collision protocols CORA and mDEFAR [14] that both highly perform for dense and mobile deployments of readers compliant with the scenarios depicted. They perform similarly to results obtained in [14,16].…”

A Survey of RFID Readers Anticollision Protocols

“…The priority levels are set depending on the success of readers during previous contentions. Another version of this algorithm was proposed in [17] to address mobile deployments. While these solutions improve the fair access to shared medium among readers, they rely on a precedent beacon exchange which is itself subject to collisions.…”

“…6) Coverage Oriented Reader Anti-collision (CORA): CORA [17] is aimed at time critical RFID systems. After selecting a timeslot in the available range, readers exchange beacons to inform their neighbors.…”

“…Based on our observations, distributed TDMA-based algorithms are all-around less profitable than the others. This can be explained by their unawareness of the [29] CORA [17] GD-MRSOA-AIS [18] DCNS [22] GDRA [27] DCS [20] NFRA [25] DEFAR [23] NFRA++ [26] PDCS [21] CASE [30] MALICO [24] CSMA HiQ [13] APR [31] DiMCA [32] EDMC [33] HAMAC [19] LBT [16] Pulse [15] EMRCA [34] TABLE II: Reader anticollision protocols system configuration which can be very random in dense and mobile environments. Basing the readers activity on a local information at a given time is insufficient to have a proper working solution.…”

“…Pulse [15] or LBT [16]; for high mobility and density with low delay but not collision sensitive applications (smart cities, preventing forest fires, warehouse goods tracking, etc.) CORA [17] if the application is collision sensitive but not delay sensitive (harbor dock loading and unloading, etc.) GD-MRSOA-AIS [18] is the best trade-off.…”