Research Of On-Vehicle Location System Based On GPS And SMS Of GSM

Location system has been applied in lots of domains. In the past many location systems used the mathematical location method which was in the carrier. These ways were complicated. In order to locate the carrier, the worker had to operate the math equipment to get the location data. A cheap and great location method is provided by GPS (Global Positioning System) for all the people in the world. The GPS receiver gets the carrier's location data endlessly. Remote sensing locating comes true by sending the data which is carried by the SMS.This design is an on-vehicle location system based on GPS and SMS of GSM, which could meet owner's location needs. There are two parts in the design: on-vehicle part and monitor part. The on-vehicle part is to receive the valid GPS data and control the SMS of GSM (Global System for Mobile communication) module. The monitor part is to send the locating request message and get the message which has the GPS data and display the encoded GPS data.TC35i module made in Siemens is used as GSM. GPS receiver and TC35i module are controlled by the SCM-AT89S52's serial ports in the two parts. In The on-vehicle part, the AT89S52 need to control two modules. AT89S52 have a pair of serial ports. Considering the application of this design, the system needs GPS data when it has been requested. The SCM can choose the connection of its serial port using a switch chip named 4066. Also the power circuit, IGT circuit and SIM card circuit are introduced in detail. In the monitor part the serial port communication between SCM and PC is very important.C51 programs in this design. SCM send AT instruction to operate the reading, receiving and sending of SMS. Base flow of getting location data: the on-vehicle part's SCM receive the selective GPS data, then judge the validity and store the useful GPS data. At last the message with the useful GPS data is sent to the monitor part. In the monitor part the SCM receives the returned massage and deals with it.This design completed the function of vehicle location. The equipment in the on-vehicle part can be used on the other carrier. There could be lots of applications, such as position tracking, phone locating and guard against theft. Changing the input from GPS data to anthers, new remote monitor equipment could be created. For example, the temperature and humidity is very suitable in the rugged environment. Based on this design, the system gets more dynamic GPS data and match electronic maps. Then it becomes a navigation system. The system will have more applications.