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The RFID facts So What is RFID? Quick Links
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
specifications. 2.
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.
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.
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
Tech Aid.
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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.
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.
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.