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.

Manufacturer Information serial#, pressure, model Content, …etc Application Software Asset Management Information Inventory #, receipt, date, current location, …etc Inspection Information repair, date and location of last inspection and retest, Safety data, …etc Other data can also be programmed on request Cylinder Filling Information Content, date of last fill, place of last fill, fill counter, …etc Report Generation Comprehensive reporting, Current status, historical logs, …etc The Problem …

Constructing The Loop Distributor Customer Supplier

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

WiFi Wi-Fi setup consists of several Access Points (APs) and several clients. Each AP broadcasts its Service Set Identifier (SSID) through packets called beacons Wi-Fi setup consists of several Access Points (APs) and several clients. Each AP broadcasts its Service Set Identifier (SSID) through packets called beacons AdvantagesDisadvantages High data rate High data rate Low interference Low interference Products widely available in the market Products widely available in the market High power consumption High power consumption Needs encryption for security Needs encryption for security Interruption can occur from 2.4 GHz mobile phones and microwave ovens Interruption can occur from 2.4 GHz mobile phones and microwave ovens Adapters must be installed on each client Adapters must be installed on each client

Bluetooth Radio frequency standard Radio frequency standard AdvantagesDisadvantages Low interference because of the low power consumption Low interference because of the low power consumption Automatic recognition Automatic recognition Each transmission consumes 1 milliwatt of power Each transmission consumes 1 milliwatt of power Max distance 32 feet Max distance 32 feet Not the cheapest Not the cheapest

Infrared Signals Light waves of a lower frequency than human eyes can receive and interpret Light waves of a lower frequency than human eyes can receive and interpret AdvantagesDisadvantages Interference between devices is uncommon Interference between devices is uncommon "line of sight" technology "line of sight" technology "one to one" technology "one to one" technology Speed of data rate transmission is lower than typical wired transmission Speed of data rate transmission is lower than typical wired transmission

Home RF Radio frequency standard Radio frequency standard AdvantagesDisadvantages Enhances mobility Enhances mobility No transmitter interaction/interfe rence No transmitter interaction/interfe rence Low Cost Low Cost Blocked by common materials: people, walls Blocked by common materials: people, walls Short range Short range Speed of data rate transmission is lower than typical wired transmission 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. 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. 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. 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. 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 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

3 rd Order Butterworth LPF

Frequency Response of Butterworth Filter All frequencies above 912 MHz are filtered out. All frequencies above 912 MHz are filtered out. Phase shift at 912 MHz is about -100 degrees. Phase shift at 912 MHz is about -100 degrees.

Input and Output Signals of 912 MHz LPF

Half Bridge Power Amplifier Voltage Gain = 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 voltage is the same for all frequencies. Output current does not depend on frequency. Output current does not depend on frequency. Therefore Power Gain is constant. Therefore Power Gain is constant.

Transmitted Power Input voltage = V Input voltage = V Input current = mA Input current = mA Input Power = 31.6 mW Input Power = 31.6 mW LPF output voltage = 0.49 V LPF output voltage = 0.49 V LPF output current = mA LPF output current = mA LPF output power = 36.3 µW LPF output power = 36.3 µW Amplifier output voltage = 0.4 V Amplifier output voltage = 0.4 V Amplifier output current = 8 mA Amplifier output current = 8 mA Amplifier output power = 3.2 mW Amplifier output power = 3.2 mW

Read Range Assumptions: No propagation loss No propagation loss Transmission antenna gain is 1 Transmission antenna gain is 1 No noise !!!! No noise !!!! P R = P T G R (c/f) 2 /(4πr) 2 For P R = 1 pW r 2 = P T G R (c/f) 2 /P R (4π) 2 r 2 = P T G R (c/f) 2 /P R (4π) 2 = [3.2 x x 9 x ] G R / [(912) 2 x x x(4π) 2 ] = [3.2 x x 9 x ] G R / [(912) 2 x x x(4π) 2 ] = x 10 6 G R = x 10 6 G R r = 1.48 (G R ) 1/2 Km r = 1.48 (G R ) 1/2 Km

Demodulator Circuit

How the circuit works Assuming the tag uses ASK modulation: Assuming the tag uses ASK modulation: 1 is represented by a 5V sine wave 1 is represented by a 5V sine wave 0 is represented by 1V 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 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. 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. 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. 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: 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 Adding security codes to the transmitted signal Using an advanced demodulation circuit to decode other types of modulated signals. Using an advanced demodulation circuit to decode other types of modulated signals.

References Han05 Han05 –Gerhard Hancke. A practical relay attack on ISO proximity cards, Lee03 Lee03 –Youbok Lee. Antenna circuit design for RFID application. Microchip Technology, Application Note AN710, DS00710C, Sch05 Sch05 –Bruce Schneier. RFID passport security revisited. Schneier on Security: A weblog covering security and security technology, _1.html. _1.html _1.html

References TI03 TI03 –S4100 multi-function reader module data sheet. Texas Instruments, Module , f f f f

Thank you Questions ?