Anticollision Protocols for Single-Reader RFID Systems: Temporal Analysis and Optimization

TLDR

RFID systems must read many tags rapidly, but collisions among tag replies hinder scalability, prompting the development of MAC protocols based on aloha and tree schemes. The authors introduce a new performance metric, time system efficiency, to evaluate anticollision protocols. This metric directly measures the time required to read a group of tags, and the authors assess several established RFID MAC protocols using it. Using the metric, they design a new anticollision protocol that significantly outperforms existing mechanisms.

Abstract

One of the major challenges in the use of Radio Frequency-based Identification (RFID) on a large scale is the ability to read a large number of tags quickly. Central to solving this problem is resolving collisions that occur when multiple tags reply to the query of a reader. To this purpose, several MAC protocols for passive RFID systems have been proposed. These typically build on traditional MAC schemes, such as aloha and tree-based protocols. In this paper, we propose a new performance metric by which to judge these anticollision protocols: time system efficiency. This metric provides a direct measure of the time taken to read a group of tags. We then evaluate a set of well-known RFID MAC protocols in light of this metric. Based on the insights gained, we propose a new anticollision protocol, and show that it significantly outperforms previously proposed mechanisms.