RFID based multipurpose identity card PROJECT

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RFID GENERAL DETAILSMain parts in our system are1

(1)RFID reader (2)RFID tag (3)AT 89C51 (4)RTC (5)LCD (6)Keypad (7)Max 232 (8)EEPROM (9)Power Supply RFID is the radio identification its an ADC(automated data collection) technology which uses : 1. Radio frequency waves to transfer data between a reader and movable item to identify categories and track. 2. It is fact and does not require physical sight or contact between readers/scanners and tagged item. 3. It performs the operation using low cast components. 4. It attempts to provide unique identification and backend integration that allows for wide range of application. Overview: Other Automated Data Collection technologies2

1.Barcodes It is a leading ADC technology. First barcode patent was issued in 1934. In 1970s the UPC standard was adopted by grocery industry. More than 250 barcode schemes exist. It is one of the most accurate ADC method error rate is 10000 time lower in manual keyboard entry. Use to encode numeric or alpha numeric character. As it is having so many advantages its good idea but the main thing is it needs line of sight between the reader and the bar. 2.Magnetic Stripes It is a thin plastic film containing small magnetic particles whose pole orientation can be used to encode data. It is widely used in financial applications. Advantages: Large data storage capacity. Data can be altered. Disadvantages: Stripes must be in contact with the scanning equipment for reading. It is expensive. 3.Optical Character Recognition Specially designed alphanumeric characters machine readable optical reading device. Both horizontal and vertical features must be analyzed during decoding. Advantages: Character can be read by humans and machine. Disadvantages: Manually operated scanning required some skills.3

First read rate often less than 50%. High substitution error rate. Near contact scanning required. Lower scanning rate.

4.Radio Frequency Identification (RFID) It is a considered as one of the best alternating to other ADC. It uses RF technology. Communication occurs in two directions. HOW IT IS: An identification tag with electronically encoded data is attached to the item. This tag is a transponder. It is a device capable of emitting a signal of its own. When it receives a signal from an external source, consist of microchip antenna. The reader transmits low level RF magnetic field that serve as the power source for the transponder when it is close enough. When activated the tag sends data to reader through RF. The reader decodes and validates RF signal before transmitting it to collection computer system. Advantages: NO need of line of sight. RFID SYSTEM COMPONENT DIAGRAM:







RFID COMMUNICATION: The following diagram simply explain the communication between tag and the reader. There is a communication channel between the tag and the reader.

The RFID reader continuously emits radio waves up to certain rang. The passive tag receive energy form the5

radio waves and get activated. The reader then gives command to the tag. Tag receives command and gives response to the reader. It can be easily understood from above diagram. LIMITING FACTORS FOR PASSIVE RFID 1. Reader transmitter power. (Govt. limited) 2. Reader receiver sensitivity. 3. Reader antenna gain. (Govt. limited) 4. Tag antenna gain. (size limted) 5. Power required at tag. (silicon process limited) 6. Tag modular efficiency. DETAILS OF OPERATIONAL FREQUENCIES FOR RFID


Frequency Ranges Typical Max Read Range (Passive Tags) Tag Power Source Data Rate Ability to read near metal or wet surfaces

LF 125 KHzShortest 1-12

HF 13.56 MHzShort 2-24 Generally passive tags only, using inductive or capacitive coupling Moderate

UHF 868 - 915 MHzMedium 1-10 Active tags with integral battery or passive tags using capacitive storage, E-field coupling Fast

Microwave 2.45 GHz & 5.8 GHzLongest 1-15 Active tags with integral battery or passive tags using capacitive storage, E-field coupling Faster

Generally passive tags only, using inductive coupling Slower

Better Access Control & Security Identifying widgets through manufacturing processes or in harsh environments Ranch animal identification Employee IDs





Library books Laundry identification Access Control Employee IDs

supply chain tracking Highway toll Tags

Highway toll Tags Identification of private vehicle fleets in/out of a yard or facility Asset tracking




MATERIAL Cardboard

EFFECT ON RF SIGNAL Absorption (moisture) Detuning (dielectric) Absorption Detuning (Dielectric) Reflection Complex effects (lenses, filters) Reflection Absorption Detuning(dielectric) Reflection

Conductive liquid (shampoo) Plastics Metals Group of cans

Human body/animals



RFID READER1. Readers are devices which continuously emits radio frequency up to certain range depending upon the type of reader used. 2. It is a trans-receiver which can transmit as receive an information using radio frequency. 3. These devices can be hand-held or portable depending upon the application. 4. The typical reader has an antenna to communicate with the tag. The size and the form of the antenna depend on the application and frequency used.9

5. There are two main classes of RFID readers: (a)Read only Reader. (b)Read/write type of reader. A. Read only reader: These reader are capable of only reading the information on the tag. We can not change the information on the tag. B. Read/write type of reader: These reader can read the information on the tag as well as this have capability of change the information present on the tag. REDAER FUNCTIONING: It is used to power up the tag. It established bidirectional data link. It can communicate with network server. Inventory tags and filter results. It can read 100 to 300 tags per tag. These readers can be fixed or mobile type.

READERs GENERAL ANATOMY: A typical reader generally has following parts 1. Digital Signal Processor. 2. Network Processor. 3. Following Radio modules a. 915MHz b. 13.56MHz c. 125KHz10


Probable PCB mounted diagram for RFID reader with RS232 Interface



The above shown is the probable PCB mounted diagram of typical RFID reader for understanding purpose. There are two processors these are DSP and N/W processors. DSP deals with the radio frequency signals. The other circuitry is also shown in the diagram. There is a coil antenna which is quit big in size with other components. This antenna is used for radio wave transmission. There are also four pin outs as follows: 1. VCC: This is for providing required voltage to circuit. 2. GND: For grounding purpose. 3. Sout: Signal out pin to interface with RS232. 4. En : This is kept at ground level. Readers can also be categorized as follows: A.RS232 READERS 1. These readers provide raw data on the RS232 port every time the tag is read. 2. Data is not stored insight the reader and will be lost if controller or PC connected to it does not read it. 3. Controller can offer many features regarding RFID readers as per their requirement.13

B.READERS WITH TCP/IP & controller 1.These readers have TCP/IP Ethernet LAN controller as well as inbuilt controller with limited functionality. 2.These readers can be connected to the LAN network and can be configured to send data to the server. 3.These are efficiently used over many systems. RFID READER VENDORS: PRINTER ENCODE Zebra Printronix Datamax Sato FIXED READER HAND HELD READER TI Symbol Intermec Intermec Matrices Hand Held Products Alien PCS AWD PSION TEKLOGIX Thing Magic



Specific functionality & tag support optimize for supply chain applications Maximum performance for read rate range. Middleware require for application integration.

Embedded feature in another product. Optimum performance given cost space and power requirement. Single, Intuitive application interface native to reader.

RFID TAGS1. RFID Tags are made of a small silicon chip having a rotating coil type of antenna. It is a very small circuit. 2. Tags can be attached to almost anything i. e. items cases , pallet of product, high value goods etc. 3. Vehicles, assets, livestock or personals. There are two types of tags: a. Passive tags b. Active tags A.Passive tags 1. These tag do not contain internal battery that is why these are known as Passive tags. It draws energy from interrogator field.15

2. It has lower storage capacity. 3. Shorter read range (4 inch to 15 inch). 4. Usually read-ones-write-many/read only tags. 5. Cost about 25 cents to few dollars. B.Active Tags 1. Battery Powered. 2. High storage capabilities (512kb). 3. Longer read range (300 feet). 4. Typically can be rewritten by RF interrogator. 5. It cost around $50 to $250 There are two main components present in the RFID tag. Firstly a small silicon chip or integrated circuit which contain unique identification number secondly an antenna that can send and receive radio waves. The antenna consist of flat, metallic conductive coil rather than protruding FM style aerial. These tags can be quit small, thin and increasingly easily embedded within packaging, plastic cards, ticket, clothing label, pallet and block. RFID TAG internal Block diagram


A. Read only Tags Tag Id is assigned at the factory during manufactu