The Wireless Hydrology Data Acquisition Based On ARM9 And CDMA+DTU

As the rapid development of computer software and hardware, especially the popularization of computer applied technology, embedded system and technology has been universally employed in all kinds of field in society. Nowadays, embedded system and technology has been one of the hottest issues in IT field. With characteristics of powerful functions, free of charge and abound developing resource, Embedded Linux has been dominated in embedded operating system. Therefore, it is of great importance for us to study and master theoretical knowledge and practical application of embedded system. Data collection of hydrologic regime provides important information for the operation and maintenance of reservoirs, but the tremendous invested cost and instability in data transmission of traditional hydrology measurement and reporting system reduce the quality of automatic measurement. Embedded system based on ARM9 stabilizes traditional system by connecting it with internet for the employment of embedded system in data collection of hydrologic regime achieves data transmission based on CDMA wireless network which also realizes the online monitoring of water level and rainfall. Thus it can reduce unnecessary invested cost and achieve outdoor unattended mode.This paper mainly studies the basic principles of embedded system and does research into the architecture, repertoire, operating system and development software of ARM microprocessor; by provides solution based on ARM9 embedded system, it analyzes the acquisition module and CDMA wireless data transmission of data collection of hydrologic regime, elaborately verifies the design procedure of ARM9 microprocessor and finally accomplishes not only the clipping and transplanting of Linux operating system, but also the design of corresponding device drivers and applications.For the achievement of the embedded system, this paper provides specific steps and experimental evidences of the key technology of this system. Taking ARM9 development board for experimental platform, it employs S3C2440 microprocessor of ARM9 kernel. This board is equipped with FLASH memory chip, RAM memory, serial interface, I/O docking station, A/D analog-digital converter and RTC real-time clock, etc. In order to screen the rock-bottom details and make the development of application program convenient, this system successfully transplants UBOOT guiding kernel system program and Linux operating system and the yaffs2 file system which provides the upper application program with a unified application programming interface to ARM9 development board. When it comes to data transmission, this system applies ARM9 interface which is connected with CDMA+DTU wireless transmission module to design data transmission in Linux system; when switched in internet, CDMA+DTU system can transport data by wireless networkThrough several experiments and long-time debugging, it turns out that data collection of hydrologic regime system is reliable enough to meet the designing standard of automatic acquisition and measurement of the whole data. Last but not least, in the aspect of data management, this system employs prevailing JSP WEB technology by joining CDMA+DTU module in internet. Client-side/Server architecture is employed between mobile terminal and center server; connection-oriented socket communication based on TCP/IP protocol between the two guarantees the validity of hydrologic data collection transported. In PC office terminal, it applies data management of WAN to make data examination as easy as viewing web page. It also takes full use of internet technology to unify the interfaces of wireless data.The development technology discussed in this paper is also suitable for other correlated developing programs, which also provides reference value for other embedded application systems and wireless data transmission.