Friday, December 01, 2006

RFID Standards

Standards are critical in RFID. Be it payment systems or tracking goods in open supply chains. A great deal of work has been going on to develop standards for different RFID fequencies and applications.

RFID standards deal with the following:-

* Air Interface Protocol - The way tags and readers communicate
* Data Content - Organizing of data
* Conformance - Tests that products meet the standard
* Applications - How applications are used

The way the world has gone about developing the standards is a bit complex. There are two major and somewhat conflicting organizations into the business - ISO and Auto-ID Centre (now handled by EPC Global). Without going too much into the conflict, we'll review the standards proposed by both these organizations.

Tags are required to be disposable (manufacturer may not get the tags back from the retailer to reuse it). Hence, the primary mission for any standard developer is to make the tags low cost. It should operate in UHF, as only UHF delivers read range needed for supply chain applications. And since the goods are needed to be tracked as they move across the globe, the standards must be open and globally accepted. There should also be an accompanying network architecture, which would enable anyone to look up information associated with a serial number stored on a tag. The network too needs to be based on open standards.

EPC standards for tags are the class 0 and class 1 tags:

* Class 1: a simple, passive, read-only backscatter tag with one-time, field-programmable non-volatile memory.
* Class 0: read-only tag that was programmed at the time the microchip was made

Class 1 and Class 0 have a couple of shortcomings, in addition to the fact that they are not interoperable. One issue is that they are incompatible with ISO standards. The new EPC standard ~V Gen2 is designed to be fast tracked with ISO standards but for some disagreements over the 8 bit Application Family Identifier (AFI).

ISO has developed RFID standards for automatic identification and item management. This standard, known as the ISO 18000 series, covers the air interface protocol for systems likely to be used to track goods in the supply chain. They cover the major frequencies used in RFID systems around the world.

The seven parts are:

1. 18000~V1: Generic parameters for air interfaces for globally accepted frequencies
2. 18000~V2: Air interface for 135 KHz
3. 18000~V3: Air interface for 13.56 MHz
4. 18000~V4: Air interface for 2.45 GHz
5. 18000~V5: Air interface for 5.8 GHz
6. 18000~V6: Air interface for 860 MHz to 930 MHz
7. 18000~V7: Air interface at 433.92 MHz

No comments: