Research And Design Of Network Assisted GPS System Based On ARM

This subject is based on ARM and single chip microcomputer, Linux system and Qt/E software, combined with GPS, electronic map, GPRS/GSM, touch screen, voice module,keyboard/mouse, digital tube driver and display, serial port interface technology, add the Dijkstra optimal path, universal time coordinated and East eight area conversion, serial communication XOR, navigation and positioning data scale conversion algorithm and program code, is the overall system to navigation application.The purpose of this study is to reduce the seconds of cold start time of the conventional GPS navigator, the problem of special environment can not be normal use, can not get of communication and contact with the outside world and slow speed. This design adopts GPRS/GSM network aided positioning, effectively reduce the positioning time, breaks through the traditional GPS navigator use environment limitations, uses the voice call or send location Short Message form to communicate with the outside world. MCU can receive and process a large number of navigation data, does some simple control tasks to reduce the ARM core controller workload and improve the overall system speed.This paper introduces the hardware design and related theory, such as ARM, GPS module,MCU,GPRS/GSM module and related peripherals,has a detailed description of the Linux system and the transplantation of Qt/E, the design of electronic map and the function interface. Mainly introduces the realization of some innovative design and a variety of algorithms for hardware and software. For example, the design of TTL, CMOS, RS232 level conversion circuit, cross/direct selection switch, matrix keyboard, display circuit and eight digital tube dynamic display, algorithm of time conversion, XOR and binary conversion.From a practical application point of view to design experiment,has a lot of debugging and improvement, at present the whole system runs in good condition, has fast speed of navigation and positioning, can be used in different of environment, each function interface displays smoothly, has the basic realization of navigation and positioning function, has a wide application prospect in real life.