Transcript RFID Automation

ELG 4135
Electronics ΙΙΙ Project
Professor: Riadh Habash
TA: Mohamad Eid
TA: Peng He
RFID AUTOMATION
IN AN INDUSTRIAL PLANT
SIGAS
Saudi Industrial Gas Co.LTD.
The Problem …
Manufacturer Information
serial#, pressure, model
Content, …etc
Asset Management
Information
Inventory #, receipt, date,
current location, …etc
Other data can also be
programmed on request
Application
Software
Inspection Information
repair, date and location of
last inspection and retest,
Safety data, …etc
Cylinder Filling Information
Content, date of last fill,
place of last fill,
fill counter,
…etc
Report Generation
Comprehensive reporting,
Current status,
historical logs, …etc
Constructing The Loop
Supplier
Distributor
Customer
Existing Technologies






Component cables or Electrical wires
WiFi
Infrared Signals
Bluetooth
Home RF
RFID
WiFi 802.11

Wi-Fi setup consists
of several Access
Points (APs) and
several clients. Each
AP broadcasts its
Service Set Identifier
(SSID) through
packets called
beacons
Advantages
Disadvantages
High data rate
High power
Low interference consumption
Needs
Products widely
encryption for
available in the
security
market
Interruption can
occur from 2.4
GHz mobile
phones and
microwave ovens
Adapters must
be installed on
each client

Bluetooth

Radio frequency
standard
Advantages
Low
Disadvantages
interference Max distance 32
because of the
feet
low power
Not the cheapest
consumption
Automatic
recognition
Each
transmission
consumes 1
milliwatt of
power
Infrared Signals

Light waves of a
lower frequency
than human eyes
can receive and
interpret
Advantages
Disadvantages
Interference
between devices
"line

is uncommon
of sight"
technology
"one to one"
technology
Speed of data
rate transmission
is lower than
typical wired
transmission
Home RF

Radio frequency
standard
Advantages
Disadvantages
Enhances
Blocked by
mobility
common
materials: people,
No transmitter
interaction/interfe walls
rence
Short range

Low
Cost
Speed
of data
rate transmission
is lower than
typical wired
transmission
Why is RFID better than
using bar codes?




Bar codes are line-of-sight technology, which means
people usually have to orient the bar code towards
a scanner for it to be read. Radio frequency
identification, by contrast, doesn’t require line of
sight.
RFID tags can be read as long as they are within
range of a reader.
Bar codes have other shortcomings as well. If a
label is ripped, soiled or falls off, there is no way to
scan the item.
Standard bar codes identify only the manufacturer
and product, not the unique item. The bar code on
one cylinder is the same as every other, making it
impossible to identify which one might pass the
inspection.
RFID – An Idea Whose
Time Has Come
•Radio Frequency Identification (RFID) is a
technology with several aspects that correspond to
different applications.
•The common element of all RFID applications is the
use of radio signals to sense the presence of a
tagged object and, in most instances, to retrieve
data stored on the object.
What is RFID? (Continued)

From the sensing point of view, the many RFID
applications are quite diverse, including
– Radar
– Access control systems and smart cards
– Automatic toll collection
– Asset tracking (e.g., railroad cars)
– Animal tagging, including implants
– Hazardous substance tracking
– Inventory and supply chain tracking
RFID Components




RFID transponder or an RFID tag :
There are several methods of identification, but the most
common is to store a serial number that identifies a person
or object, and perhaps other information, on a microchip
Tag is attached to an antenna The antenna enables the chip
to transmit the identification information to a reader.
The reader converts the radio waves reflected back from the
RFID tag into digital information that can then be passed on
to computers that can make use of it.
Friendly software
Components of an RFID system Figure (1)
Example RFID Tags
Labels with RFID tags embedded
2.5 mm coil-on-chip RFID tag for close
proximity applications (Maxell)
Gas Cylinders
SIGAS SOLUTION
RFID High level System
Design
125 KHz Low Pass Filter
3rd Order Butterworth LPF
Frequency Response of
Butterworth Filter


All frequencies
above 912 MHz are
filtered out.
Phase shift at 912
MHz is about -100
degrees.
Input and Output Signals
of 912 MHz LPF
Half Bridge Power
Amplifier
Voltage Gain = 0.816
Current Gain = 108
Power Gain = 88
Cross over distortion
avoided by 2 diodes
Frequency Response of
Power Amplifier



Output voltage is
the same for all
frequencies.
Output current does
not depend on
frequency.
Therefore Power
Gain is constant.
Transmitted Power









Input voltage = 1.549 V
Input current = 20.418 mA
Input Power = 31.6 mW
LPF output voltage = 0.49 V
LPF output current = 0.074 mA
LPF output power = 36.3 µW
Amplifier output voltage = 0.4 V
Amplifier output current = 8 mA
Amplifier output power = 3.2 mW
Read Range
Assumptions:
 No propagation loss
 Transmission antenna gain is 1
 No noise !!!!
PR = PTGR(c/f)2/(4πr)2
For PR = 1 pW
r2 = PTGR (c/f)2/PR (4π)2
= [3.2 x 10-3 x 9 x 1016 ] GR / [(912)2 x 1012 x 10-12 x(4π)2]
= 2.193 x 106 GR
r = 1.48 (GR)1/2 Km
Demodulator Circuit
How the circuit works





Assuming the tag uses ASK modulation:
1 is represented by a 5V sine wave
0 is represented by 1V sine wave
Comparator gives 1 if the envelope detector
output is higher than 2V and 0 if envelope
detector output is less than 2V
For a 1 followed by 0, the capacitor will
discharge starting from 5V until output falls
below 2 V and the comparator output will
change to 0.
Demodulation Results (1)

Assuming the input
is all 1’s, the
amplitude of the
modulated signal is
always 5V. So the
comparator output
will always be 1.
Demodulation Results (2)

Assuming the input is a
series of 1 followed by
0, the modulated
signal amplitude will
alternate between 5V
and 1V. So we can
model this case by
applying an input
signal of lower
frequency to give the
envelope detector
enough time to
discharge.
Future Improvements

Increasing power efficiency:
– Matching antenna impedance
– Improving the LPF and power amplifier
– Including noise considerations in circuit design


Adding security codes to the transmitted
signal
Using an advanced demodulation circuit to
decode other types of modulated signals.
References

Han05
– Gerhard Hancke.
A practical relay attack on ISO 14443 proximity cards, 2005.
http://www.cl.cam.ac.uk/~gh275/relay.pdf.

Lee03
– Youbok Lee.
Antenna circuit design for RFID application.
Microchip Technology, Application Note AN710, DS00710C, 2003.
http://ww1.microchip.com/downloads/en/AppNotes/00710c.pdf.

Sch05
– Bruce Schneier.
RFID passport security revisited.
Schneier on Security: A weblog covering security and security
technology, 2005.
http://www.schneier.com/blog/archives/2005/08/rfid_passport_s
_1.html.
References

TI03
– S4100 multi-function reader module data sheet.
Texas Instruments, Module 11-06-22-715, 2003.
http://www.ti.com/rfid/docs/manuals/refmanuals/rf-mgr-mnmn_ds.pdf.

http://en.wikipedia.org/wiki/Bluetooth, 2006

http://techtrain.microchip.com/webseminars/documents/IrDA_BW.pd
f

http://trace.wisc.edu/docs/ir_intro/ir_intro.htm

http://en.wikipedia.org/wiki/Wi-fi#Wireless_Access_Point_.28WAP.29
Thank you
Questions ?