The RFID facts
So What is RFID?
There isn't a day goes by when you don't
read another article about RFID in one magazine or another. And
the sad thing is they are being written by people who often do
not have a clue as to what RFID is or how it works. Many of them
are not involved in the RFID world on a daily basis and the
things they report are often "hearsay" and opinion from others.
Here are a few of the facts as we see them, as well as some
opinions from someone who is working in the arena.
1. Standards are a long way off! -
WRONG. Whether you are talking ISO or EPCglobal™ the standards
are NOT a long way off. In the ISO world, the standards for
2.45GHz, UHF (860 - 960MHz), 433MHz (active), 125-134kHz and
13.56MHz are complete and published. T The main vendors of these
products have been working in the ISO arena to help create these
standards and so are fully aware of the technical
In the EPCglobal™ world, things are moving just as fast. The
Generation 2 UHF specifications have been published. The
Generation 2 HF specifications are almost complete and are
expected in late 2008.
What is the difference between ISO
and EPCglobal™ UHF specifications? - Many have questioned
the difference between ISO and EPCglobal™ UHF specifications and
why we have two different sets of specifications. When the work
in ISO started, there was no EPCglobal™
and the consensus was that we needed a standard to provide the
full read/write capabilities with memory. Thus the ISO standard
which was originally published was for a full read/write tag
without references to a numbering system. The tag can be used
for any UHF application. This has been subsequently updated to
add an Amendment for a Type C which is basically identical to
the EPCglobal™ Gen 2 UHF specification.
The EPCglobal™ world set a goal for a low
cost tag at the basic level. So it has limited functionality
(depending on class) (read only, limited memory etc.) and has a
reference to a numbering system. The class system allows for
more functionality at increased cost levels. The ISO standard
allows for more than the basic tag.
3. EPCglobal™ Generation 2 is a read
only tag! - WRONG. The concept of the EPCglobal™ system is
to have several classes of tags that define the functionality.
When the original Class 0 and Class 1 tags were approved it was
realized that they are not compatible with each other and that
there is no path forward to make higher class tags that have
backward compatibility. At the same time some users were
suggesting that the current Class 0 and 1 specifications were
inadequate for their needs. So EPCglobal™ decided to move on to
a Generation 2 of EPC tags. From the original ideas, Class 1
tags are Write Once Read Many (WORM) tags with minimum memory to
hold the EPC number. Class 2 tags are passive field programmable
tags with user memory, encryption, etc. Class 3 tags are
semi-passive tags with user memory, encryption, etc. And Class 4
tags are active tags with user memory, encryption, etc. The
ideal goal is to have one protocol that talks to all forms of
UHF tags - this is Generation 2.
4. Class vs. Generation? - A quick
way to help understand this easily misunderstood area is to
think as follows: Classes define the capability of the RFID tag
from Class 0 to Class 4. Each Class has more capability than the
one below it and is backwards compatible. Generations refer to
the revisions of the specification. The first version (or
generation) of Class 0 and Class 1 tags has been posted to the
EPCglobal™ web site. Generation 2 will apply to several
classes of tag.
5. Patent issues will kill RFID! -
WRONG. In the ISO arena there is a policy which states that
standards should use technology that is freely available where
possible. If technology exists that is protected by patents etc.
and that technology is needed to implement a system, then the
company holding the IP (Intellectual Property) signs an
agreement to make it available to everyone on fair and
reasonable terms without discrimination. This is how the ISO
18000 standards have been created.
In EPCglobal™ the original goal was to have
a Royalty Free (RF) set of specifications. However, in the field
of RFID many people have put a lot of time and money into
developing technology and they have patents that protect their
work. This means that it is very difficult to design an RFID
system that does not infringe on one or more of these patents.
EPCglobal™ has stated they will possibly allow RAND (Reasonable
and Non Discriminatory) licensing of technology as a alternative
to RF. This may prove to be necessary when all the research is
concluded. However, this is most likely to be a license to
manufacture hardware and is unlikely to affect the user
NOTE: EPCglobal™ only requires its
"members" to sign documents about declaring IP required to
implement the specification ahead of time. The thousands of
patents held by companies that are not members of EPCglobal™ are
still out there, and though they are mostly application patents,
they may be an issue.
6. All applications can be accomplished
with UHF! - WRONG. Or at least partly wrong. There are six
frequency ranges that RFID technology is allowed to operate in.
They are LF (125 - 135 kHz), HF (13.56 MHz), 433 MHz, UHF (860-
960 MHz), 2.45 GHz, and 5.8 GHz. Each of these frequency areas
has advantages and disadvantages. Many applications can be
accomplished using UHF technology but some of them will not work
as well as they might with other frequencies. UHF technology is
good when longer distance reads are needed, but many companies
have seen problems with UHF when exposed to liquid or metal
objects. Other frequencies that are far less susceptible to the
effects of these materials may be a much better solution (LF or
HF are better for these applications). If an application needs
to be compliant with others using UHF, then it is obvious that
this is the best way to go. If it is a closed application then
there are many choices in the RFID world and some of them may be
much better than UHF.
7. RFID will not take off until the tags
cost less than five cents! - WRONG. For many projects you do
not need a $0.05 tag to be able to justify the project. The cost
of RFID tags has been high. Many vendors are still charging in
the $0.50 range. The cost of a tag is defined by many things:
cost of silicon, silicon processing, die handling and attachment
process, antenna design, form factor of tag. Each of these
processes has to be optimized to get the lowest cost tag price.
Many companies are working to do this, not just for EPCglobal™
tags but for all RFID tags. The final factor in all this is
volume. If there is a large enough order, the price will fall as
economies of scale come in to play. This is true for all
frequencies of RFID tags. Of course some tags will always be
more expensive than others, the cost of a wire antenna is likely
to always be more than that of a printed one. The five cent tag
is still in the future when manufacturing techniques have been
devised to help reduce the cost, but many applications can show
a good ROI on tags at the $1.00 - $0.50 level.
8. RFID is available now! - RIGHT.
The ISO 18000 standard are available for purchase, the
EPCglobal™ Generation 2 specification is available on line, RFID
is available now in many different forms. RFID is NOT NEW. There
have been commercial applications of RFID available for more
than ten years. While standards are good and very important, if
you are implementing a closed system, the technology you need
may well be available right now.
9. I must implement RFID or my
competitors will overtake me! - WRONG. Although there is a
lot of stories about RFID, the one where it is going to save
your company and ensure large profits for the rest of your life
probably isn't true. As with all business decisions, you need to
look carefully at the need for RFID and determine if there is a
Return on Investment or a mandate that says you must implement?
10. RFID is going to take away our
privacy! - WRONG. Privacy is important to all of us, but
there are sometimes reasons that we are prepared to give away
some of that privacy. Think about cell phones, loyalty cards,
credit cards. Each of these has taken away some of our privacy
but we are willing to sacrifice to get the advantage of the
item. RFID will be very similar. We will be willing to share
information on some things to gain the advantages it will give
us. Should it be government controlled - absolutely NOT. Should
the end user be made aware of the issue - YES.
RFID tags cannot be read by a satellite in
the sky. They do not contain your life history (or your
purchasing history). You cannot tell what color underwear
someone is wearing, simply by reading the tag in a library book.
To tie any of these things together will require access to many
databases and presume knowledge that will difficult to find.
I hope these ten points will further your
understanding of RFID and its availability. Once you understand
these points, you can start to think about the application needs
(and ROI if you need to). Next you need to find the best form of
RFID for your application (frequency etc.).
If you need help or advice on selecting the
best RFID type for your application, call or email us at High
High Tech Aid