As we talk about RFID a lot, the Tech Geek has been asked the following questions: “What is RFID? How does it work?” School of RFID has been constantly investigating this topic, and now some light will be shed on our findings.
In this series of articles, the Tech Geek shares the basics of
RFID with you. Maintaining the RFID Arena and writing in-depth
articles have taken much effort in form of research and have
engaged several talented RFID-minded investigators and experts. The
articles and blog posts published on the RFID Arena are only the
peak of an iceberg - several great writings are still lying in the
drawers. The Tech Geek opened one of the drawers and compiled a
series of technical articles out of the researches conducted by
School of RFID. Let's get busy.
How does RFID work?
The victorious path of RFID relates to the fact that it is a
technology unlike any other. Usually, RFID is understood as HF to
UHF technologies. Now we concentrate on UHF Gen 2 technologies
since they are the current standard that for example the retail
business has chosen to adopt.
Radio-frequency identification (RFID) is a sensor technology
based on smart tags, which are attached to different surfaces and
items. The microchip in the tag stores a small amount of data. In
all cases, an RFID system consists of a tag, an interrogator (a
reader) and a computer system network.
Tags are mini-sized radio transmitter/responders
("transponders") that store and broadcast data. Tag types are many,
as well as sizes, shapes and capabilities of them. The data in the
tag can be a simple identification number for identifying the
object the tag is attached to. Most often the tag contains only a
number, which serves as a key to a record in a database on the host
back end system, which stores the actual data. When the tags are
scanned with a reader, they broadcast their contents. The reader
catches the information and sends it to the host back end. The host
can use the data in an application program, such as a system for
warehouse management, inventory, ERP or a database.
Nearly all RFID applications operate on four different
frequencies: low frequency (LF), high frequency (HF), ultra-high
frequency (UHF) and microwave (MF). Item-level tagging typically
uses UHF tags, which operate on between 860 and 930 MHz
frequencies. NFC tags operate on high frequency.
The use of RFID traces back to the World War II, though the
commercial applications were taken into use not before the 1980s.
The early application areas have mainly consisted of road tolls,
live-stock tracking and manufacturing. After these the commercial
applications have been introduced. The adoption of technology in
new business areas has been favored by advancements in
technological development and constantly decreasing prices of
tags.It is estimated that the most rapid growth in RFID will come
from retail and consumer goods. (Harrop, Das & Holland 2011).
IDTechEx, the total RFID market in 2015 is worth $10.1 Billion,
and the estimation for 2020 is up to $12.3 Billion.
The building blocks needed
An RFID system needs four components for performance: individual
tagged items, an RFID reader, tags and the software including the
Each of the items has an own tag attached. Each tag holds a
unique identifier like a serial number, therefore each product is
individual. There are various types of tags on the market for
different purposes. A reader can be a wireless mobile computer or a
fixed reader installed at a gateway, at the cash register or even
on the ceiling. In addition, there must be software for both the
RFID reader and for the back end system in order to inform of
product details, follow stock levels and perform store
In a nutshell, this is how it works: When searching for a
specific product, the reader sends a command for each of the tags
filling specific conditions to respond. The reader can ask for
instance all the black t-shirts size S of model X from collection Y
to answer. When the tag answers, it sends its own identifier as a
reply. The reader gets the details matching the identifier from the
back end system and therefore it knows that the specific garment is
there. In taking inventory, the reader reads all the tags it finds
with conditions set while the salesperson is sweeping the mobile
reader close to the clothes in a shop. Then the mobile reader
reports the findings: it can tell the number of tags found, the
percentage of tags found compared to the information of the back
end system… This is much up to the user application.
In 2016, apparel industry alone will demand 4.6 Billion RFID
IDTechEx). This is important for the fashion industry, since
the SKU (stock keeping unit) counts are high and the turnaround
time on items is fast. With a high number of SKUs, shrinkage seems
to be a remarkable problem as well. In addition, a high potential
for OOS (out of stock) situations leads to loss of sale. There
already is evidence about how retailers have been able to eliminate
shrinkage, reduce losses of sale and have the RFID investment pay
for itself in a rather short time.
Next time the Tech Geek tells you about
radio technology and radio waves. To be continued…
Brown, Dennis E. (2007) RFID Implementation. McGraw-Hill
Harrop, Das & Holland (2011): Apparel RFID 2011-2021.
Tajima, M. (2007) Strategic value of RFID in supply chain
management. Journal of Purchasing & Supply Management, Vol. 13,