post details Interfacing-GPS-GSM-8051-Microcontroller | Interface-GPS-89C51-89C52-89S81-89S52-Microcontroller | GPS+GSM+Interfacing
Interfacing GPS Modem+ GSM Modem 8051 Microcontrollers

Interfacing Global Positioning System (GPS Modem) and GSM Modem With 8051 Microcontroller :
When we talk and listen about GPS it means a GPS receiver.The Global Positioning System (GPS) is actually an installations of 27 earth revolving satellites 24 satellites in operation and extra 3 for in emergency use. The U.S. military developed and implemented this satellite network as a military navigation system, but soon opened it up to everybody else. A GPS receiver's job is to locate four or more of these satellites, figure out the distanc­e to each, and use this information to deduce its own location. This operation is based on a simple mathematical principle called trilateration. Trilateration in three-dimensional space can be a little tricky, so we'll start with an explanation of simple two-dimensional trilateration.

Interfacing GPS and GSM Modem With 8051 Microcontroller
In this GSM and GPS Interfacing with 8051 Project it is designed for tracking and positioning the running vehicle all over the globe using Global Positioning System (GPS) and send SMS using GSM Modem about the current location of the vehicle. In the project we use 8051 microcontroller for interfacing GSM Modem and GPS Modem and other hardware devices which are compulsory for running the project.

GSM Modem and GPS Receiver is directly interfacing 89S51 Microcontroller using serial port protocol to send and receive data. Using RS232 protocol integrated ic. The GPS modem constantly receiving the data from the satellite and start sending it to microcontroller. Information given by GPS modem is in the Latitude and Longitude and GSM modem is used to send SMS the received information from GPS in the form of Latitude and Longitude to the selected number. There information is processed and find out the current location of the vehicle.

An EEPROM a storage device is used to store the mobile number and current location of the vehicle. The the main hardware components are 89S51 Microcontroller, GPS Receiver and GPS Modem. A serial interface is used to communicate by the 89S51 Microcontroller to send and receive data from GPS Modem and send it to GSM Modem.

Hardware Circuit and its Operation (Soon will be Uploaded Here)
In the Vehicle Positioning and Navigation System we can locate the vehicle anywhere in the global using simple but advanced devices with 8052 Atmel or NXP micro controller, GPS receiver, GSM modem, MAX 232, EEPROM. for storage and Microcontroller used is AT89S52 or 51. GPS pin TX which is referred as transmit pin is connected to microcontroller using MAX232. GSM pins TX and RX are also connected to microcontroller serial ports. AT89S51 Microcontroller communicates using serial communication with the help of RS232 protocol. It takes data from the GPS receiver and then sends the information in the form of SMS with help of GSM modem.

GPS Modem receiver works on a specified baud rate is used to get the data from from Satellites, the GPS values received then send to the microcontroller AT89S51-52, where these are processed and forwarded to GSM Modem. The power is supplied to components like GSM, GPS and Micro control circuitry using a 12V/3.2A battery .GSM requires 12v,GPS and microcontroller requires 5v .with the help of regulators we regulate the power between three components.

The GPS module continuously sends serial data in the form of sentences according to NMEA standards. The latitude and longitude values of the location are contained in the GPGGA sentence in NMEA. In this program, these values are extracted from the GPGGA sentence and are displayed on LCD. Microcontroller accepts data from GPS from serial communication using RS232 protocol. The extraction of the data is taken place.

Software Developed and Its Operation (Will Be Uploaded Here)
The software used in the project developed in Keil C. As a programme flow as specified above are into following steps:

1. First GPS Modem sends the data to the microcontrollers LAT and Long.
2. Then Microcontroller study the given data and store it to serial eeprom.
3. After processing and filtering data is sent to the GSM Modem.
4. GSM modem sends the data in the form of SMS to selected device.
5. There the data is processed and location is tracked and displayed on the screen.