ELG 4135

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• ELG 4135
• Electronics ??? Project
• Professor Riadh Habash
• TA Mohamad Eid
• TA Peng He

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RFID AUTOMATION IN AN INDUSTRIAL PLANT
SIGAS Saudi Industrial
Gas Co.LTD.
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The Problem
Manufacturer Information serial, pressure,
model Content, etc
Other data can also be programmed on request
Asset Management Information Inventory ,
receipt, date, current location, etc
Cylinder Filling Information Content, date of
last fill, place of last fill, fill
counter, etc
Application Software
Report Generation Comprehensive
reporting, Current status, historical logs, etc

Inspection Information repair, date and location
of last inspection and retest, Safety data, etc
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Constructing The Loop
Supplier
Distributor
Customer
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Existing Technologies

• Component cables or Electrical wires 
• WiFi
• Infrared Signals
• Bluetooth
• Home RF
• RFID

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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

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Bluetooth

• Radio frequency standard

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Infrared Signals

• Light waves of a lower frequency than human eyes
  can receive and interpret

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Home RF

• Radio frequency standard

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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, doesnt
  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.

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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.

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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

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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

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Components of an RFID system Figure (1)
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Example RFID Tags
Labels with RFID tags embedded
2.5 mm coil-on-chip RFID tag for close proximity
applications (Maxell)
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Gas Cylinders
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SIGAS SOLUTION
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RFID High level System Design
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125 KHz Low Pass Filter
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3rd Order Butterworth LPF
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Frequency Response of Butterworth Filter

• All frequencies above 912 MHz are filtered out.
• Phase shift at 912 MHz is about -100 degrees.

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Input and Output Signals of 912 MHz LPF
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Half Bridge Power Amplifier

• Voltage Gain 0.816
• Current Gain 108
• Power Gain 88
• Cross over distortion
• avoided by 2 diodes

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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.

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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

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Read Range

• Assumptions
• No propagation loss
• Transmission antenna gain is 1
• No noise !!!!
• PR PTGR(c/f)2/(4pr)2
• For PR 1 pW
• r2 PTGR (c/f)2/PR (4p)2
• 3.2 x 10-3 x 9 x 1016 GR / (912)2 x
  1012 x 10-12 x(4p)2
• 2.193 x 106 GR
• r 1.48 (GR)1/2 Km

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Demodulator Circuit
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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.

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Demodulation Results (1)

• Assuming the input is all 1s, the amplitude of
  the modulated signal is always 5V. So the
  comparator output will always be 1.

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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.

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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.

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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/rfi
  d_passport_s_1.html.

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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/documen
  ts/IrDA_BW.pdf
• http//trace.wisc.edu/docs/ir_intro/ir_intro.htm
• http//en.wikipedia.org/wiki/Wi-fiWireless_Access
  _Point_.28WAP.29

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Thank you
Questions ?