GPS Module of Software, Hardware Structure And Analysis
The GPS module hardware design, often make the GPS module and serial 1serial connected, module and antenna can be connected with a preamplifier.The antenna can choose Toshiba antenna, can also be customized. You can select the LCD screen display, time, longitude and height data. The power supply adopts 4 alkaline battery, easy replacement.
MCU can use TI's MSP430flash (F13X) series. MSP430 series of 16 bit single chip microcomputer, fast processing speed, low power consumption, small size,suitable for use in portable instruments. At the same time, MSP430 singlechip C language support, easy programming.
Screen menu using character and western language display, can shorten development time, reduce the cost, it is suitable for civil use; also can choose thecolor large screen LCD, friendly interface, beautiful, but the software workload,high cost of hardware. Select the 3 touch keyboard, menu function can be achieved by software. Because the power MSP430 microcontroller 3.3V TU30 and the power for the 5V, so the need for processing power DC-DCconversion module. If the battery charging circuit also need. The interface principle of GPS module and the monolithic integrated circuit as shown in fig..
The GPS module software structure
The software flow chart of GPS module. The preparation of the main software is a serial communication, parameter display and man-machine interface is set up between the GPS module and MCU. Including initialization, serial port communication, data processing, the fault tip, display, keyboard processing,power management etc.. The initialization includes various registersconfiguration MSP430, configuration parameters (baud rate, serial correlationmodel (LCD) and the peripheral circuit, power supply and other test equipment)initialization etc.;
Serial communication including data sending, receiving, checking,communication fault prompt; data processing is mainly for receiving datadecoding, storage and data refresh; fault tips include equipment failure,communication failure, power failure. Power management is the main powerundervoltage tip and current power status display.
In addition, the design should also be noted that when the antenna module of GPS requirements, the following specific points:
(1) the antenna gain is 30dB, the impedance is 50 ohms.
(2) radio frequency signal environment requirements, namely the carrier frequency RF input L1 is 10MHz, bandwidth center point should be 0dBW.
Application of GPS module navigation equipment focuses on the multi satellite system, remote monitoring and multi function display. The use of multi satellite system (such as the GNSS integrated navigation system) navigation, satellitecan ensure the accuracy and reliability of many real-time positioning.
In addition, the GPS module is positioned by GPS network restrictions, control network application of GPS satellite positioning technology called GPS net. To sum up can be divided into two categories: one category is the high precision GPS network global or national, adjacent to the GPS network in the distance of thousands of kilometers to tens of kilometers, its main task is as a framework for global high precision coordinate or national high precision coordinate frame,think global earth dynamics and space science scientific research in the field ofservice. Another kind is the regional GPS network, including the city or area GPS network, GPS network, in this network between adjacent points in a distance of several kilometers to tens of kilometers, its main task is to directly serve the national economic construction.