Premnoitoring of railway station using GSM



GSM Modem based Railway premonitory system





Electronics and Communication Engineering

Session 2010-2014

Department of ECE

Submitted To:-                                                             Submitted By:-       

Er. Mandeep Kaur                                                                               Mohit Sood


Index/ List Of Figures

S. No.TopicPage No.
2Introduction in Brief3
3Design of Problem Solution8
4Methodology Planning of Work10
5Facilities provided for proposed work  12



  • GSM Railway Pre Monitoring system
  • wireless Transmission and Reception of data


In this project we will sense We will use  GSM modem to monitorrailway gate open or close. We will send SMS on particular No. It’s the latest technology available in market .We will use SIM300 or SIM 900 modem for this puspose.We will use AT commands to send sms from mobile. In this we divided project in to two section. Transmitter circuit and receiver circuit. In transmitter section we will generate sms when any barrier close detected from sensor section then our arduino main control using will generate a character message and will send to receiver section. We used GSM modem for transmission of SMS. GSM modem needs 5v VCC, ground and serial input from arduino. Gsm modem follows AT commands from arduino.

In receiver section we used GSM modem to receive message.Our GSM modem will receive message and will give signal to Modem . Modem will dispplay data on 16×2 LCD.


  • Sensor Circuit
  • GSM Modem
  • GSM modem Max 232 interface circuit
  • Arduino Circuit
  • Power Supply

In this sensor unit  it is our choice , how many sensor’s  we use , IN this project we use two sensor’s, In this project we use two electronics circuit with infra red sensor’s and Humidity sensor alarm sensor.In the infra red sensor. We use ic 555 as a main component. Pin no 4 and pin no 8 is connected to the positive supply. Pin no 1 is connected to the negative voltage. One capacitor is grounded from the pin no 5 for noise cancellation. Output is available on the pin no 3. Sensor is connected to the pin no 2.

In the case of infra red sensor. Pin no 2 is negative bias through the 33k ohm resistor and pin no is positively biased through the photodiode. One infra red transmitter l.e.d is  focused to the photodiode . Infra red l.e.d is directly connected to the positive and negative supply through the 470 ohm resistor..

In normal stage when light is focus on the photodiode then  pin no 2 is positively biased photodiode. If pin no 2 is positive then  negative  output is available on the pin no 3. Now when any body interrupt the light then  there is no light on the photodiode and pin no 2 is now gets its voltage from only 33 k ohm resistor.  If pin no 2 is become negative then  output is shifted to the  pin no 3. when positive output is available on the pin no 3 and with the help of this voltage  NPN transistor is on and npn transistor provide a negative voltage as a pulse to the microcontroller.

If we connect two sensor as a input to the microcontroller then we use same circuit with the ic 555 .

 Note that microcontroller sense only negative input to the microcontroller.

We will use GSM modem sm300 at 9600 baud rate.

GSM modem

This GSM modem is a highly flexible plug and play quad band GSM modem for direct and easy integration to RS232. Supports features like Voice, Data/Fax, SMS,GPRS and integrated TCP/IPstack.

Specifications for Fax

· Group 3, class 1

Specifications for data

· GPRS class 10: max 85.6 kbps(downlink)

· PBCCH support

· Coding schemes CS 1,2,3,4

· CSD upto 14.4 kbps


· Non transparent mode

· PPP-Stack


· Quad Band GSM/GPRS

850/900/1800/1900 Mhz

· GPRS multi-slot class 10/8

· GPRS Mobile station class B

· Compliant to GSM Phase 2/2+

o Class 4 (2W@850/900Mhz)

o Class 1(1W@1800/1900Mhz)

· Control via AT commands(GSM 07.07,

07.05 and enhanced AT commands)

· Operation Temperature(-20 deg C to

+55 deg C)

Specifications for SMS

· Point-to-point MO and MT

· SMS cell broadcast

· Text and PDU mode

Power Supply

· Use AC – DC Power Adaptor with following ratings

· DC Voltage : 12V

· DC Current : 1A

· Polarity : Centre +ve & Outside –ve

· Current Consumption in normal operation 250mA, can rise up to 1Amp while transmission.


· RS-232 through D-TYPE 9 pin connector, Serial port baud rate adjustable 1200 to115200

bps (9600 default)

· Stereo connector for MIC & SPK

· Power supply through DC socket

· SMA antenna connector

· Push switch type SIM holder

· LED status of GSM / GPRS module

Getting Started

· Insert SIM card: Press the yellow pin to remove the tray from the SIM cardholder. After properly fixing the SIM card in the tray, insert the tray in the slot provided.

· Connect Antenna: Screw the RF antenna on the RF cable output provided.

· If voice call is needed, connect the mic and speaker to stereo sockets.

· Connect RS232 Cable: (Cable provided for RS232 communication) Default baud rate is 9600 with 8-N-1, no hardware handshaking. Cable provided has pins 7 and 8 shorted that will set to no hardware handshaking. In you need hardware handshaking the pins 7-8 can be taken for signaling.

  • Pin 2 is RS232 level TX out
  • Pin 3 is RS232 level RX in
  • Pin 5 is Ground
  • Pin 7 RTS in (shorted to pin 8 in cable for no hardware handshaking)
  • Pin 8 CTS out (shorted to pin 7 in cable for no hardware handshaking)

Connect the power Supply (9-12V) to the power jack. Polarity should be Center +ve and outer –ve DC jack.

Network Led indicating various status of GSM module eg. Power on, network registration & GPRS connectivity.After the Modem registers the network, led will blink in step of 3 seconds. At this stage you can start using Modem for your application.

Examples for send and receive SMS

For sending SMS in text Mode:

AT+CMGF=1 press enter

AT+CMGS=”mobile number” press enter

Once The AT commands is given’ >’ prompt will be displayed on the screen.Type the message to sent via SMS. After this, press ctrl+Z to send the SMS.If the SMS sending is successful, “ok” will be displayed along with the message number.

For reading SMS in the text mode:

AT+CMGF=1 Press enter

AT+CMGR= no.

Number (no.) is the message index number stored in the sim card. For new SMS, URC will be received on the screen as +CMTI: SM ‘no’. Use this number in the AT+CMGR number to read the message.

Design Of Problem

Methodology/Planning Of Work

Methodology used in this project is we will get low high pulse at input of Microcontroller. From Microcontroller we will use AT command to communicate with GSM modem. There will be 5V DC regulated supply for whole circuit to work. IR sensor will work as a variable resistor. And Thermocouple will work on thermal properties.


Summary of circuit features

  • Brief description of operation: Gives out well regulated +5V output, output current capability of 700 mA.
  • Circuit protection: Built-in overheating protection shuts down output when regulator IC gets too hot.
  • Circuit complexity: Simple and easy to build.
  • Circuit performance: Stable +9V output voltage, reliable operation.
  • Availability of components: Easy to get, uses only common basic components.
  • Design testing: Based on datasheet example circuit, I have used this circuit successfully as part of other electronics projects.
  • Applications: Part of electronics devices, small laboratory power supply.
  • Power supply voltage: Unregulated DC 5-18V power supply.
  • Power supply current: Needed output current 1A.
  • Components cost: Few rupees for the electronic components plus the cost of input transformer.



This circuit is a small +05 volts power supply, which is useful when experimenting with digital electronics. Small inexpensive wall transformers with variable output voltage are available from any electronics shop. Those transformers are easily available, but usually their voltage regulation is very poor, which makes them not very usable for digital circuit experimenter unless a better regulation can be achieved in some way. The following circuit is the answer to the problem.

This circuit can give +05V output at about 1A current. The circuit has overload and terminal protection.


                                  IN 4007                                   

                                                                       1                       3                      +12V


                                                                               1000 uf                                 470 uf

                              Circuit diagram of power supply

The above circuit utilizes the voltage regulator IC 7805 for the constant power supply. The capacitors must have enough high voltage rating to safely handle the input voltage feed to circuit. The circuit is very easy to build for example into a piece of Vero board.

                                                   1      2      3

                                     Pin diagram of 7805regulator IC

PIN 1 :  Unregulated voltage input

PIN 2 :  Ground

PIN 3  :  Regulated voltage output  

Component list

  1.  7805 regulator IC.
  2.  1000 uf electrolytic capacitor, at least 25V voltage rating.
  3.  470 uf electrolytic capacitor, at least 25V voltage rating.

We are using center taped full wave rectifier and Pi- filter for filtering.

About Rectifiers

A rectifier is an electrical device that converts alternating current (AC) to direct current (DC), a process known as rectification. Rectifiers have many uses including as components of power supplies and as detectors of radio signals. Rectifiers may be made of solid state diodes, vacuum tube diodes, mercury arc valves, and other components.

A device which performs the opposite function (converting DC to AC) is known as an inverter.

When only one diode is used to rectify AC (by blocking the negative or positive portion of the waveform), the difference between the term diode and the term rectifier is merely one of usage, i.e., the term rectifier describes a diode that is being used to convert AC to DC. Almost all rectifiers comprise a number of diodes in a specific arrangement for more efficiently converting AC to DC than is possible with only one diode. Before the development of silicon semiconductor rectifiers, vacuum tube diodes and copper(I) oxide or selenium rectifier stacks were used.

Early radio receivers, called crystal radios, used a “cat’s whisker” of fine wire pressing on a crystal of galena (lead sulfide) to serve as a point-contact rectifier or “crystal detector“. Rectification may occasionally serve in roles other than to generate D.C. current per se. For example, in gas heating systems flame rectification is used to detect presence of flame. Two metal electrodes in the outer layer of the flame provide a current path, and rectification of an applied alternating voltage will happen in the plasma, but only while the flame is present to generate it.

Facilities provided for proposed work

  1. GSM modem
  2. Arduino Uno3
  3. PCB general purpose
  4. Power Lead
  5. Soldering wire
  6. Soldering Iron
  7. Multimeter
  8. push to on sw
  9. 555 timer
  10. .001 µf,0.1 µf,0.01µf
  11. 1µf,
  12. 220k,470k,4.7k,10k,
  13. Crystal 11.0592 MHz
  14. 3.38 MHz.
  15. Buzzer  9v                     
  16. Condenser MIC
  17. Speaker 8 ohm
  18. Relay 12v 100 ohm
  19. Transformer 6v 500mA
  20. Connecting wires
  21. Copper clad board


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