嵌入式微弱信号采集系统设计与实现

发布时间：2018-03-11 01:28

本文选题：微弱信号　切入点：嵌入式　出处：《重庆大学》2014年硕士论文　论文类型：学位论文

【摘要】：信号检测是人们了解自然的基础，随着科学技术以及理论研究的加深，对信号检测的极限提出了更高的要求，因此诞生了微弱信号检测这一新兴的学科。微弱信号的兴起吸引了大批科研工作者的关注。微弱信号的采集作为微弱信号检测的一部分，自然也引起了极大的关注，研究出了众多的科研产品，代表的有锁定放大器、取样积分器等。这些仪器都有一个共同的特点，就是设备先进、价格昂贵，只适用重大研究项目中。鉴于这一缺陷，本文分析了微弱信号采集中的关键技术，拟搭建一套面向大众的完整的微弱信号采集系统，实现对模拟信号处理与数字信号采集，从而达到在上位机识别微弱信号的目的。本文首先对微弱信号检测的相关知识做了介绍，介绍了微弱信号的特点、国内外现状等，分析出成本低廉的微弱信号采集系统的应用前景，从而提出了将嵌入式和虚拟仪器结合到一起，形成嵌入式微弱信号采集系统的思路。接着针对嵌入式微弱信号采集系统，提出以FPGA和LabVIEW为中心解决方案。细化设计方案，为放大滤波、AD采样、传输控制和系统软件选择了合适的开发平台，并给出了依据。然后根据解决方案对系统的组成部分进行分析和设计研发。硬件部分给出了放大滤波、AD采样和控制传输几个模块的电路根据硬件系统需求以及与软件系统的交互，嵌入式系统完成了指令解释、采样控制以及数据读写等功能，同时对USB固件的修改使得传输端口专属于采集设备软件系统具备了与设备的数据交互以及对数字信号的处理，实现了上位机对采样信号的重现和存储功能。最后进行了系统的调试。通过对各个硬件和软件模块的调试，，以及总体调试，实现了对微弱信号的采集功能。
[Abstract]:Signal detection is the basis of people's understanding of nature. With the deepening of science and technology and theoretical research, the limit of signal detection has been put forward higher requirements. As a result, weak signal detection, a new subject, has attracted the attention of a large number of researchers. As a part of weak signal detection, the acquisition of weak signals has naturally aroused great concern. Many scientific research products, such as locking amplifiers, sampling integrators and so on, have been developed. These instruments all have a common characteristic. Is that the equipment is advanced, the price is expensive, only applies in the important research project. In view of this flaw, this paper analyzes the key technology in the weak signal collection, plans to build a set of complete weak signal acquisition system for the public. Analog signal processing and digital signal acquisition are realized, so that weak signal can be recognized on the upper computer. This paper first introduces the relevant knowledge of weak signal detection, introduces the characteristics of weak signal, the current situation at home and abroad, and analyzes the application prospect of low cost weak signal acquisition system. The idea of combining embedded instrument with virtual instrument to form embedded weak signal acquisition system is put forward. Then, aiming at the embedded weak signal acquisition system, the paper puts forward a solution centered on FPGA and LabVIEW. The detailed design scheme selects a suitable development platform for AD sampling, transmission control and system software for amplifying and filtering, and gives the basis. Then, according to the solution, the components of the system are analyzed and designed. The hardware part gives the circuits of the AD sampling and control transmission modules based on the hardware system requirements and the interaction with the software system. The embedded system has completed the functions of instruction interpretation, sampling control and data reading and writing. At the same time, the modification of the USB firmware makes the transmission port belong to the acquisition equipment software system with the data interaction with the device and the processing of digital signal. The function of reproduction and storage of the sampling signal is realized by the upper computer. Finally, the system is debugged. Through the debugging of each hardware and software module, as well as the overall debugging, the weak signal acquisition function is realized.
【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN911.23;TP274.2

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