PULSE: A MAC Protocol for RFID Networks

Abstract

Abstract. The reader collision problem occurs when the signal from one reader interferes with the signal from other readers. Solutions like RTS-CTS are not applicable because a reader may communicate with multiple tags simultaneously. In this paper, we describe Pulse, a distributed protocol to reduce reader collisions. The operation of the Pulse protocol is based on periodic beaconing on a separate control channel by the reader, while it is reading the tags. The protocol functions effectively with fixed as well as mobile RFID readers. We show, using simulation in QualNet, that using Pulse protocol, the throughput (overall read rate) is increased by as high as 98%(with 49 readers) as compared to "Listen Before Talk" (CSMA) and by 337%(with 9 readers) as compared to Colorwave. We also present an analytical model for our protocol in a single hop scenario.

How to Improve CSMA-Based MAC Protocol for Dense RFID Reader-to-Reader Networks?

“…Pulse [2] is CSMA-based protocol which is proposed to resolve hidden terminal issue. Pulse proposes the use of two non-interfering channels: control channel and data channel.…”

“…The state-of-the-art protocols can be broadly classified as CSMA-based [2,11,20] and activity scheduling based [1,3,6,7,15] through time division, frequency or by putting together both approaches. The former approach is considered as an efficient and more adaptive approach in large-scale RFID reader networks because it is full-distributed algorithm and it does need neither synchronization nor additional resource (e.g.…”

Optimal Scheduling in Single Channel Dense Reader RFID Environments

“…In this approach, both tags and reader positions must be known in advance, making a real implementation difficult if mobile readers are considered. Pulse [12] is a protocol based on Listen Before Talk (LBT) strategy. It makes use of an auxiliary control channel and readers simultaneously listen the control and the reading channel, but only transmit in one of them.…”

Reader Anti-collision in dense RFID networks with mobile tags

“…Some, like HiQ-learning [10] use a hierarchical architecture to provide an online learning of collision patterns of readers and assign frequencies to the readers over time. Others, such as [1], [7], [11], [12] apply a carrier sense multiple access (CSMA) based algorithms to detect collisions. These solutions, although efficient, cannot be used in mobile tag applications since they either need a stabilization time to learn certain patterns or are probabilistic.…”

“…As a result, two or more readers can be active at the same time and are able to successfully read tags if and only if they do not interfere. This technology is applicable to several fields such as distribution centers, inventory, transportation, e-passports, baggage tracking in airports etc 1 . In distribution…”