RFIDiom have extensive experience in working with different RFID frequencies, standards and protocols. We are often engaged to integrate multi discipline RFID technologies within various production processes; supply chain systems and security applications.
During a previous assignment, we were contracted to assist in the pilot stage of a dual RFID technology based Document Tracking application in a libraries’ distribution centre. The current process consisted of two HF (13.56 MHz) RFID standards for tracking (ISO 15693) and security (ISO 14443). The system consisted of a line-side reader attached across a roller-conveyor system; which was used to transport HF-tagged books, pamphlets and loose-leaf A4/A5 paper documents.
RFIDiom were tasked to integrate a near-field coupled (NFC) Gen2 UHF RFID (ISO 18000-6C) system alongside the current line-side installation. The purpose behind this was to phase out the HF based tracking system in favour of the faster and cheaper near-field UHF RFID.
The project was broken down into several key stages and some preliminary feasibility studies were carried out in order to understand the performance limitations and potential implications on the current system:
Inlay (label) evaluation and selection
- Carry out detailed and rigorous performance testing on a selection of NFC optimised EPC Gen2 inlays across a wide range of acceptable label sizes and silicon technologies;
- Survey EPC Gen2 protocol features across different chip vendors;
- Implement smart Tag Data Encoding schemes (eg. GRAI-170) based on EPC Global data structure definitions.
- Conduct performance and EPC Gen2 feature tests on primary and alternative UHF RFID (line-side) readers;
- Investigate various near-field UHF antennas for optimised NFC performance;
- Investigate and rectify any cross-modulation issues across different HF/UHF RFID readers.
- Determine optimum UHF RFID label positions on various items (boxes, books, brochures and A4/A5 loose-leaf documents);
- Advise on operator ‘best practices’ and performance limitations.
- Conduct RF site surveys and adjust reader transmission power and channel allocations accordingly;
- Determine RF shielding requirements for reader isolation and interference limitation;
- Calibrate RFID read-zones and optimise proximity sensor detection and rejection fields;
- Optimise reader parameters, firmware settings and TCP/IP network configuration.
Schematic illustration of HF/UHF RFID line-side reader operation showing multiple tag reads on books, A4/A5 documents and container trays
RFIDiom were able to successfully integrate Gen2 UHF RFID technology alongside the client’s existing line-side HF RFID system within a relatively small time-frame.
Issues relating to system interoperability were quickly identified and rectified using tried and tested engineering techniques. Using strategically positioned antenna arrangements and adept reader channel allocations, we were able to eliminate interference and cross-modulation issues.
Our pragmatic and rigorous UHF inlay selection procedures resulted in optimum reader performance levels with highly consistent read rates and read accuracies to 100 %.
Our work has allowed the client to begin to phase out the current ISO 15693 HF RFID system in favour of the faster and cheaper UHF RFID technology. This will allow the client to increase process speeds for quicker distribution times on selected lines.