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The RFID facts
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), and 433MHz
(active) are already approved and will be published in mid August 2004.
The standards for 125-134kHz and 13.56MHz are complete and in the final
ballot stage. The ballots will be complete at the beginning of August
2004 and publication will be shortly after that. 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 specifications and
have already started production in some cases to anticipate the
publication.
In the EPCglobal™ world, things are moving just as fast. The
specifications for the original (Generation 1) Class 0 and Class 1 tags
have been published and there will be interoperability testing done in
the summer. The new Generation 2 specifications are also moving along
and are close to completion (technically). There are various steps that
have to be taken before acceptance and publication of this specification
and final publication is expected to be in October 2004. The main
vendors of the EPC technology are all participating in the work and so
should know what is happening in advance of the publication of the
specification to allow hardware designs to start as soon as possible.
2. 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 will be
published in mid August is for a full read/write tag without references
to a numbering system. The tag can be used for any UHF application.
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
community is ready to adopt whatever EPCglobal™ comes up with as the
Generation 2 air interface and move it forward as a version C of the ISO
18000 standard.
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 Class1 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. The new work on UHF Generation 2 is progressing
well and should be available in the Fall. 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 community.
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 50 cents level.
8. RFID is available now! - RIGHT. Although you cannot buy an ISO
18000 standard yet (mid August 2004) or see the EPCglobal™ Generation 2
specification (Oct 2004?), 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 Tech Aid.
Steve Halliday
President
High Tech Aid
http://www.hightechaid.com
steve@hightechaid.com
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