Research On Embedded Wireless Data Acquisition System And Its Application Based On ARM

Data acquisition is an important means to obtain external information for people, it is an indispensable segment for all sorts of measurement and control system. With the advent of Internet age, the traditional way of data collection has been unable to adapt to the new production requirements. At the request of Jianguan instrument company, this paper proposed an embedded wireless data acquisition system based on ARM, which combined the embedded technology with measurement and control technology well, it aimed to achieved a reconfigurable and scalable modular system structure. This issue surrounds universality of the data acquisition system to makes an in-depth researches on the aspects of system structure, work mechanism, software platform and device interfaces.This issue takes material testing machine as the object in the process of research, and applies our system model on it, the emphasis of tasks are as follows:(1) In order to improve the utilization and sharing of data, the structure of the whole system would be separated into acquisition module and processing module. Data acquisition terminal is responsible for the comprehensive data extraction, and data processing terminal chooses the information according to their own needs to get the corresponding results. Moreover, in allusion to the redundancy of hardware, this paper puts forward the ARM+FPGA hardware structure in acquisition terminal. Using FPGA to implement phase differentiation and quadruple subdivision of the grating sense. Additionally, it also dominates AD to sample the S strain sensors etc.(2) Uses the embedded Linux operation system as software platform, from three aspects:the bootloader, kernel, rootfs to configure and construct the embedded system circumstances, and for a dedicated hardware platform, writes our particular bootloader.(3) As most wireless transmission methods are facing with the problems of slow transmission rate, small coverage and so on, this paper uses WIFI to transmit data between the acquisition module and processing module, and completes the transplantation of RT3070 wireless WIFI driver on Linux system. On the upper level communication protocol, using the Socket programming to change communication mode from the traditional point-to-point mode to C/S mode, and finally beat the target of information sharing.(4) In view of the network communication security issues, in-depth research on the Netfiler frame and kernel encryption frame under Linux, using Linux network security subsystem to build firewalls and encryption system.(5) Data processing module uses the Visual C++ to implement GUI design, mainly accomplishes the analysation and processing of the data, adopts the form of curve to display the data for user, and the user can interact with the system by means of the software.The examination consequent demonstrates that this design can satisfy the various functions and index of data acquisition system, and the whole system has a high degree of flexibility and reliability.