04-10-2012, 03:58 PM
A Seminar Report on RFID Technology
RFID Technology.ppt (Size: 1.62 MB / Downloads: 62)
What is RFID?
RFID is an ADC technology that uses radio-frequency waves to transfer data between a reader and a movable item to identify, categorize, track...
RFID is fast, reliable, and does not require physical sight or contact between reader/scanner and the tagged item
What Constitutes an RFID System?
One or more RF tags
Two or more antennas
One or more interrogators
One or more host computers
Appropriate software
RFID Operation
Sequence of Communication
Host Manages Reader(s) and Issues Commands
Reader and tag communicate via RF signal
Carrier signal generated by the reader (upon request from the host application)
Carrier signal sent out through the antennas
Carrier signal hits tag(s)
Tag receives and modifies carrier signal
“sends back” modulated signal (Passive Backscatter - FCC and ITU refer to as “field disturbance device”)
Antennas receive the modulated signal and send them to the Reader
Reader decodes the data
Results returned to the host application
What is RFID? -- The Tags
Tags can be read-only or read-write
Tag memory can be factory or field programmed, partitionable, and optionally permanently locked
Bytes left unlocked can berewritten over more than100,000 times
Are All Tags The Same?
Variations:
Memory
Size (16 bits - 512 kBytes +)
Read-Only, Read/Write or WORM
Type: EEProm, Antifuse, FeRam
Arbitration (Anti-collision)
Ability to read/write one or many tags at a time
Frequency
125KHz - 5.8 GHz
Physical Dimensions
Thumbnail to Brick sizes
What is RFID? -- The Readers
Readers (interrogators) can be at a fixed point such as
Entrance/exit
Point of sale
Warehouse
Readers can also be mobile -- tethered, hand-held, or wireless