1. EPCglobal Class-1 Generation 2 UHF RFID
Todd Humes, CTO Impinj, Inc. 501 N 34th Street, Suite 100 Seattle, WA

2. An RFID Chip More transistors than the processor in a 1985 IBM PC-AT
Lower power consumption than a honeybee’s brain

3. RFID Hardware Overview
Wafers
Tags
Reader

4. RFID is Old, what’s New
New standards at UHF (900 MHz) vs HF (13.56MHz)
UHF - 10X range of HF RFID
Faster data rates – up to 640kbps
But, presents many new challenges:
How to identify and read/write single tags from hundreds within a reader field...
Tag and reader RF interference...
Security....
Tag data processing...
Solution - EPCglobal Gen2 standard

5. Example data exchange:
RFID Systems
Network layer
Air Interface
RFID Reader
Tag
Tag IP
Network
RFID Reader
Tag
Tag
RFID Reader
Example data exchange:
Forward
Return
Link parameters
Tag inventory
Link rates and encoding formats
Singulation parameters, tag identification

6. What do I do? Tag Identification Suppose…you are all tags
You are all blindfolded
You are nearly deaf
You talk by whispering
You can’t hear each other
Suppose…I’m a reader
I’m blindfolded
I don’t know who is in the room
I need to yell so you can hear me
If two of you talk at once, I can’t understand you
I’m not allowed to say your name
I may hear many others like me screaming in the same room
I need to identify everybody in the room
What do I do?

7. Reader Environments Operating Environment Single-reader environment
A region within which a reader’s RF transmissions are attenuated by less than 90dB (roughly a sphere with a 1km radius)
Single-reader environment
A single reader operating in the environment
Multiple-reader environment
# of simultaneously active readers < # of available channels
Example: 10 readers operating in 50 channels
Dense-reader environment
# of simultaneously active readers  # of available channels
Example: 50 readers operating in 50 channels
Readers require knowledge of operational deployment and the ability to adjust their RF parameters for a given environment -ie. One non-dense reader in a dense reader deployment will spoil the whole frequency plan

8. Air Interface Control Gen2 features Purpose S/W Control
Tag selection and identification
Singulation control and options for faster inventories
Q-algorithm, Boolean selection, truncated replies
Dense reader mode
Allows for a large number of closely spaced readers with minimal interference and optimized data rate for high noise or high speed comm
Forward link options – DSB-ASK, SSB-ASK, PR-ASK Return link options – Baseband or subcarrier backscatter
Sessions
Multiple readers talk within same tag population
e.g. dock door reader + handheld
Choice of four sessions
Variable data rates
Link closure in varied environments
Configure forward link (Tari, pulsewidth) and reverse link (preamble type, data rate, encoding - FMO or Miller)
Kill and access password
Security
Password validation and management