Train information and control system based on RFID
PRINCIPLE OF Track Circuit Train Control (TCTC):
The system transfers control information through railway track. Each track circuit is a close division with certain length. Sender and receiver are located in the start and end of the division.The value of the track circuit resistance, is crucial because it will influence the value of current transferred to the control center. If the current is weak, the position will not be indicated at the moment.

RFL(Radio frequency identification location system)
It consists of RF-card, Read/Write device and management system. The Read/Write devices consist of wireless transceiver, antenna,
controlling module and interface circuit . The RF-card can read or write intelligently within encrypted communication. RFL systems are classified as low frequency, intermediate frequency and high
frequency.The high frequency system works at 850- 950MHz or 2.4-5 GHz for long distance or high rate of reading/writing data. The low frequency system refers to 100- 500kHz and intermediate frequency system is about between 10-15 MHz. and are mainly used in short distance or low cost application.

CBTC
It is is an advanced control system using wireless communication. Itâ„¢s a flexible and safe new generation of train control system with strong functions. there are 5 parts in CBTC: MSC( mobile switch center), BSC(base switch controller), BTS(base transfer station), MS(mobile station) and CL(connection line).

WORKING PROCEDURE:
When train is running on the railway, the RF-read/write device will read the data from the RF-card and is displayed to the train driver and transferred to control center through the CBTC and thus the trainâ„¢s position is located.When the train runs between two RF-cards, the location could be calculate by formula:
Location= Mileage(data from just passing RF-card)+Speed*Time .

full report:

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