RFID technology

RFID technology is not new technology. One of the first papers about RFID is published in 1948 by Harry Stockman. RFID was developed during 1940’s, but the use of technology was limited due to high costs of the RFID tags. Commercial use of RFID starts during 1960’s, with the electronic article surveillance (EAS) system, animal tagging, toll road payment systems, and using RFID in automotive industries for assembly lines.

The Electronic Product Code (EPC) is a common way for automatic and unique identification of objects (parts, products, pallets, locations, etc.), i.e. „a standard product coding structure for item management applications.

A simple RFID system includes three main components: tag, reader, and computer or enterprise system. Tag is composed of a small microchip and an antenna and can be embedded into or attached to objects of any kind (e.g. parts, products, tools, animals, persons). Tags have different shapes and sizes and have a memory for data storage. These are specific data such as a unique identification number, product price, product location, date of manufacturing, current inventory, type, description, dimensions, and so on.

There are two basic types of tags: passive (without internal batteries)&active (with battery, self-powered).

The frequency used for RFID application is an important characteristic of the RFID system.

Presently only a few frequencies are consistent around the world. There are different operational frequency ranges:low frequency (LF) 125–134 kHz,high frequency (HF) 13.56 MHz,and ultra-high frequency (UHF) RFID uses 868–928 MHz

Higher frequency enables reading at longer distances and also faster communication. Low-frequency passive tags have an effective range of approximately 30 cm, while high-frequency passive tags are useful in the range of about 1 m. Ultra-high frequency (UHF) passive tags have a range of about 8 m . Active tags are self-powered and more expensive than passive tags but can reach a range of 100 m.

RFID improves the data accuracy, accelerates processes, enables the traceability and the visibility of products throughout supply chains, increases the speed of physical flows, and reduces of Work- In-Progress and inventories.

The use of RFID technology facilitates automation of processes and improves operations management through reduction of workload and elimination of human errors.

However, RFID technology has some advantages over the bar code:

• there is no need for line of sight (tags can be read through different materials),
• suitable for harsh environments (i.e.dirt, moisture, dust, chemicals, high temperatures),
• the RFID reader could interact with multiple tags and automatically receive information from the tags,
• RFID readers greater distances of reading,
• tags contain more data than bar codes,
• form and dimensions of tags could be various, depending on the application.

There are some limitations to RFID application, i.e. physical limitations (difficulties with reading through liquid or metals).