Kwara State Polytechnic Ilorin Real Time School Bus Tracking System Using (rfid)

CHAPTER FOUR
4.1    ENGINEERING BLOCK DIAGRAM AND DESCRIPTION

As you are able to see in the above fig. there is the engineering block diagram of our project that we have designed at the primary stage of our project.
    So, the diagram consist of RFID tag, RFID reader, if transmitter receive, signal conditioning unit, microcontroller, load cell, amplifier, ADC,  LCD display then what is the follow of the diagram? So, the flow starts from the RFID tag which is detected by the RFID reader and sends the data i.e types & no of vehicle stored in 12digit code form in the tag to the controller to match with data base provided at both.
    Then the 1R transmitter receivers’ assembly will detect the exact location of the vehicle on the load cell plate to actuate weighing operation. The load cell then weights the vehicle accurately and transmits the analog signal through the instrumentation amplifier to comparator where it is compared with the stored data.
    The controller then compares the signal with the stored value of respective toll and displays on LCD.
    This is the simple working of our engineering block diagram that we have designed at the primary stags.
4.2    How does RFID works
    A radio frequency identification has three parts
-    A scanning Antenna
-    A transceiver with a decoder to interpret the data
-    A transponder the RFID tag that has been programmed with into the scanning antenna puts out radio frequency signals in a relatively shorts range. The RF radiation does two things.
-    It provides the RFID tag with the energy to communicate (in the case it passive RFID tags)
    This is an absolutely key part of the technology; RFID tag do not need to contain batteries and can there remain usable for very long period of time (may be decade)
    The scanning antennas can be permanently affixed to a surface; handheld antennas are also available. They can take whatever shape you need; for example, you could build them into a door frame it a school bus to accept data from person or objects passing through.
    When an RFID tag paste through the field of the scanning antennas it detects the activation signal from the antenna. That “wake up” the RFID chip, and it transmits the information on it’s microchip to be picked up by the scanning antenna.
    RFID tag, can be read in a way wide variety circumstances, where barcode or other optically read technologies are useless
-    The tag need not be on the surface if the objects (and is therefore not subjected to wear)
  -    The read time is typically less than IOD millisecond
-    large numbers of tags can be read at once  rather than items  by item.
    In essence, that how RFID works.