Sunday, May 12, 2013

RFID Technology in Supply Chain


A supply chain requires seamless flow of goods between the point of origin and the point of consumption, in order to meet the requirements of consumers.  Physical tracking of merchandise in a supply chain is a challenge today. Visibility into the logistics network is critical to ensure optimal inventory level and better co-ordination of different stages / departments in a supply chain. Automatic  identification techniques like RFID makes this process faster, more efficient  and accurate.

Radio Frequency Identification(RFID) is a reliable and fast growing  automatic identification and data capture technology, which allows for non-contact reading to track and monitor physical objects like retail items, vehicles, documents, people etc . As it makes use of radio waves for identification, RFID doesn’t require ‘line of sight’. A reader communicates with a tag, which holds digital information (e.g., a serial number) in a microchip. The microchip, attached to an antenna, picks up signals and sends it to a reader. Each tag contains a unique serial number called the Electronic Product Code (EPC) and the antenna enables the chip to transmit the identification information to the reader.

RFID Tags

Tag is a an electronic device which uses radiofrequency antenna to communicate with the RFID reader. Information is stored in the tags as digital data that describe the object. Tag can contain large amount of such information and also can write information into it at any point of time. Hence it is getting more popular in supply chain and other industries too.

Tags can be active or passive. The active tags are self-powered whereas the passive tags use the signal from the RFID reader as the source of power.   
 
Active tags use a battery-powered transponder that emits a constant signal containing identification information. Active tags have the greatest range of all RFID tags, including search and read/write capability. Today, they have up to 128 Kbytes of storage space, but could hold more in the future.

Passive tags have no battery, but instead rely on an antenna as the power source, drawing power from the reader’s electromagnetic signal. Passive tags have a much more limited range (less than 2-3 yards), have limited storage space (as of now, 128 bytes, but could hold more in the future), and lack data manipulation capabilities.


 The RFID tag responds to the reader by broadcasting its EPC, which is a 96-bit code consisting of

Ø  8 bits of header information.

Ø  28bits identifying the organization that  assigned the code

Ø  24 bits identifying the type of product.

Ø  36 bits representing serialization   information for the product


RFID Reader

RFID tag readers are devices that scan the tags and decodes/reads the information transmitted by them. The RFID reader converts the radio waves from the tag into a form that can be passed along to an information system.  Readers that must scan multiple items, moving quickly on a high-speed conveyor or through a dock door are more expensive than the basic hand held readers.

Antenna

RFID tag readers use an antenna to communicate to the RFID tag through the tag’s antenna. Some readers have integral antenna while other can have various types and sizes of antenna fitted to them. The antenna is a critical component in the RFID system, as it has to be built for the coverage area. The antennas vary depending upon the facility location, size, area, and volume. Usually, an antenna operates in the 3-15 MHz range.

Benefits of RFID in Supply Chain

ü  Substantial productivity gains

ü   Elimination of re-labelling costs and effort.

ü  Greater accuracy

ü  Flexibility of data on the tag – e.g., goods and containers can be identified and tracked using the same tag

ü  Ability to write additional or replacement information to a tag at any stage in the supply chain.

RFID Vs Barcodes

RFID has several advantages over conventional barcodes as follows

Ø  Barcode can be read only the “line of sight “

           RFID tags need to be within the reader’s radio reach

Ø   Barcode cannot be read inside other containers

            RFID tags can be read through most materials

Ø  Barcode provide only limited information

           RFID provides unlimited information

Ø  Barcode identify classes of products

           RFID identify individual products

 In short, RFID can check goods much faster and at a lower overall cost than the conventional barcode system. However, the cost of deployment of RFID system (cost of tags / readers/software etc) are very high compared to barcodes and hence the migration of supply chains from barcodes to RFID will not happen overnight.
 
RFID – The Future…………………

Falling prices of tags and readers and the rapid strides in the standards development process is making RFID technology an increasingly viable option for pallet and case level tagging. However, the migration of supply chains from barcodes to RFID will require significant investments and will not happen overnight.