Spatial and Temporal Analysis on the Distribution of Active Radio-Frequency Identification (RFID) Tracking Accuracy with the Kriging Method

Radio frequency identification (RFID) technology has already been applied in a number of areas to facilitate the tracking process. However, the insufficient tracking accuracy of RFID is one of the problems that impedes its wider application. Previous studies focus on examining the accuracy of discrete points RFID, thereby leaving the tracking accuracy of the areas between the observed points unpredictable. In this study, spatial and temporal analysis is applied to interpolate the continuous distribution of RFID tracking accuracy based on the Kriging method. An implementation trial has been conducted in the loading and docking area in front of a warehouse to validate this approach. The results show that the weak signal area can be easily identified by the approach developed in the study. The optimum distance between two RFID readers and the effect of the sudden removal of readers are also presented by analysing the spatial and temporal variation of RFID tracking accuracy. This study reveals the correlation between the testing time and the stability of RFID tracking accuracy. Experimental results show that the proposed approach can be used to assist the RFID system setup process to increase tracking accuracy

OPTIMIZATION OF RFID SYSTEM COVERAGE IN A MANUFACTURING ENVIRONMENT

This paper compiles existing ideas, theories, and experiments across multiple disciplines to provide guidance for a company looking to implement an optimal RFID system in their production facility. The desire is to maximize the information received by the system while minimizing the cost. Four potential layouts of RFID antennas, two with overlapping antenna coverage and two with non-overlapping layouts, are first analyzed to understand the special coverage and the number of antennas required. The value of information is then quantified to determine whether higher coverage layouts are worth the additional costs associated with the higher number of antennas required. It was found that the non-overlapping network of antennas in a hexagonal lattice formation, which covers 90.7% of the production floor area, provides the highest amount of benefit when considering the system’s implementation costs. However, some companies prefer or even require a system that provides perfect information throughout the production process, so implementing an overlapping network may be considered optimal for some companies, even with the higher up front costs

RFIDcover - a coverage planning tool for rfid networks with mobile readers

Abstract. Radio Frequency Identification (RFID) finds use in numerous applications involving item identification and tracking. In a typical application, RFID tags are attached to the items and are periodically queried by readers. Using a fixed placement of readers to guarantee complete coverage of all tags in a given area at all times increases the deployment costs. Also, most practical applications do not need complete coverage at all times. It is enough to provide complete coverage periodically, say each tag being covered every τ seconds. For such applications, using mobile readers to cover the area would be more cost-effective. Given an area to be covered completely within a period τ, determining the number of mobile readers required, their placement and movement pattern, is a difficult problem. We have developed RFIDcover 1, an automated coverage planning tool, that addresses this problem. Given an application scenario and reader specifications, RFIDcover determines an optimal number of readers required to guarantee complete coverage within the specified period τ. It also generates a layout giving the placement and movement pattern of the readers. The architecture of RFIDcover is generic and extendible, making it easy to implement different application scenarios. In this paper, we present RFIDcover implementation for a retail inventory tracking application scenario and evaluate its effectiveness.