The Race is on for 3rd Generation Gen 2 Chips – And the winner is?

Ξ May 7th, 2008 | → Comments Off on The Race is on for 3rd Generation Gen 2 Chips – And the winner is? | ∇ RFID News, UHF Ultra High Frequency |

Late March 2008 major chip maker Impinj announced a new Monza 3 chip that is significantly improved over their flagship Monza 2 chip released in 2006. This new Gen 2 Chip promises increased sensitivity by up to 40% on difficult to read items such as metals, liquids and densely packed cases. In addition it has super interference rejection which also improves readability in dense RF environments. With its dual antenna input configuration tag orientation becomes less sensitive making this chip a great next generation for RFID tags.

Early April 2008 Alien Technology introduced its new Higgs 3 chip which is a significant improvement over its Higgs 2 chip design. Alien states their new chip is 25 % more sensitive to RF signals than other tags currently available.

Both chips are slated to be available as inlays and tags in summer 2008 – So the race is on to see who has the best new Gen 2 chip. These chips offer increased sensitivity, reduced RF interference, more memory and more security than the existing Gen 2 chips.

What this really means to the rest of the world is that the both new chips offer significant improvements in read rates over the previous generation making it that much easier to deploy RFID solutions.

So the real winners will not just be Impinj and Alien for the their new designs, but the end users who will now have much better read rates and therefore improved accuracy on their RFID implementations which means all of us will benefit from the improved efficiencies that will come out of the RFID deployments.

So everyone wins!

 

HF and UHF RFID Reader

Ξ May 1st, 2008 | → Comments Off on HF and UHF RFID Reader | ∇ General RFID Questions, HF High Frequency, UHF Ultra High Frequency |

Since we posted the Blog on our 13.56 MHz. (HF) and 900 MHz. (UHF) reader we have had a number of queries asking “Can the reader read both HF and UHF at the same time?”

Unfortunately the two technologies to read/interrogate the tags are completely different.

HF uses Near Field technology known as electromagnetic induction. The reader and tag literally make a transformer for communication and because of this transforming effect the read distance is very short, hence the term Near Field. Once there is a a coupling between the reader and the tag communication is established by the reader changing the amplitude (size) phase or frequency of the carrier wave to get a response from the tag. Since there can be multiple ways to read HF tags a single HF reader does not have the capability to read all HF tags. This is also one of the reasons HF tags are slower to read than UHF tags. HF also has many different encryption/decryption methods and ISO standards which also adds to the read time and makes a single reader possibility for all HF tags almost impossible to manufacture and if you could make one it would be so expensive most companies could not afford to purchase one.

UHF uses Far Field technology known as passive backscatter which is very similar to the radar gun used by law enforcement officials to check vehicle speeds. The UHF electromagnetic wave is partially absorbed by the UHF tag to power the chip and some reflects back to the reader depending on how well the tag resonates to the UHF frequency. While several years ago UHF was Gen 1 class 0 and Class 1 most of this has been replaced by Gen 2 which is a global standard for reader to tag communications. UHF Gen 2 has only two methods or ways to read a tag and that is totally dependent on the surrounding environment at the time of the read request. If the environment is RF noisy then the reader changes its read method to a slower read algorithm that eliminates the surrounding noise. This is done automatically by the reader and since either read speed is very fast users will not even know that the reader changed its interrogation method While UHF normally is Far Field technology, recent developments of small tags for item level deployment have produced the need for the UHF
to also use Near Field technology. Since the frequency is still UHF a change in antenna type is all that is needed to read NF UHF tags. Note that while you can have UHF tags that read 35 feet or more away from a reader Near Field is usually a foot or less depending on the reader power. The biggest reason for the Near Field tag is so that you can use all of the same hardware to read both Far Field and Near Field in the GEN 2 UHF frequencies.

Summary:

Unless a reader has two different antennas it can not read multiple frequencies (or different read technologies); and unless the reader has 2 separate operating systems, etc. in essence two readers contained in one enclosure you can not read an HF tag and a UHF tag at the same time.