Delft University of Technology
Faculty Mechanical, Maritime and Materials Engineering Transport Technology
J.J. Kroes Readibility of passive EPC gen1 UHF RFID
Masters thesis, Report 2005.TL.7021, Transport Engineering and Logistics.
This research project deals with the use of Radio Frequency Identification (RFID) in the supply chain. RFID is a rapidly growing and developing technology in supply chain management. RFID can be used for the automatic identification of objects, people and items by means of radio frequency. It can store more information than traditional barcodes and requires no direct line of sight to the product to be identified. This makes bulk scanning of products possible and makes RFID technology very attractive for application in an open supply chain.
RFID comes in several types: active, passive, and a combination of the two. Active RFID transponders, or tags, use an internal battery to transmit data to the system. Passive RFID tags use energy from an interrogator to transmit data. The small size and cost make passive RFID a promising candidate for use in the open supply chain, where tags are generally used just once.
However, there are still problems with passive RFID. Part of these problems is with poor readability. Problems with read-speeds and interference of product and packaging materials cause 'missed readsö. This research discusses the readability of passive RFID technology in supply chain applications. In particular it will deal with Electronic Product Code (EPC) generation 1 standard for Ultra High Frequency (UHF) RFID technology.
The main objective of this research project is to increase the knowledge of the use of RFID technology. This was done by investigating the issues with readability of current EPC UHF generation 1 RFID technology, specifically in an operational environment. What are the factors determining the limits? What are the causes for bad readability? What can be done to improve the readability?
From the tests it became clear that the readability of current EPC generation 1 UHF RFID technology is too low to implement RFID in most existing supply chains. However, if certain measures are taken RFID could be usable for tracking and tracing. The reliability of RFID can be improved by taking measures taking into account various aspects. Four ways to increase readability and use of RFID in the supply chain are:
Basic usage requirements; These requirements concern tag quality, tag placement tag time in read-field, and component interoperability. Associate the tags on a pallet with each other; Create an association of tags on a pallet with the other tags on that pallet. This association can be used to check pallet-completeness.
Stop in gate with a light system; The addition of a light system for a dock door application, with a stop-and-go rule for pallets passing through the dock door, would benefit the readability of tags. This means a longer time of tags in the read-field.
Single parcel flow; One way of solving orientation and volume problems is to have the case detection take place for one case at a time. This can be identified as a single parcel flow.
Developments in RFID technology are moving at a fast pace, with the standards and technology still maturing. Therefore, every new development will need to be tested and tried to get the maximum benefits from it. Evaluate future generations of RFID technology, and investigate the necessity of reading 100%. Reports on Transport Engineering and Logistics (in Dutch)
