自适应随机共振系统及小信号检测方法的研究

【作者】 江波；

【导师】 杨祥龙；

【作者基本信息】 浙江大学 ， 仪器科学与工程学， 2003， 硕士

【摘要】 随机共振是目前非线性学术领域的一个新兴的重要的分支。随机共振系统是一个非线性系统，在一个小的周期性调制信号作用下同时输入噪声和信号，当噪声增强到某一强度的时候，信噪比不仅不会降低，相反系统会产生随机共振从而使输出信号得到显著的增强。随机共振技术跟传统的信号检测方法相比具有很明显的优越性，它的最大的特点是利用噪声来增强系统对微弱信号的检测能力，并且不会损害信号量。 本课题从工程实际需要出发，在深入研究随机共振机理的基础上，将其拓展到工程应用性研究中去。从理论到仿真，从工程测量背景分析到自适应随机共振算法，进行系统的研究，并建立自适应随机共振信号检测系统。 本文的主要内容包括： 1．介绍了随机共振研究的历史、现状和发展；阐述了随机共振的理论。 2．研究了噪声、信号和非线性系统之间的关系，以及产生随机共振的系统条件。 3．研究了非线性系统特征，构建实用于检测强噪声背景下弱信号的特征信息的自适应随机共振算法。 4．建立应用于工业现场的自适应随机共振信号检测系统的设计方案，完成系统界面以及上位机软件的实现，并进行了相应的调试和测试。 5．将该系统应用于中频开关电源的故障信号检测项目中，并取得了很好的效果。 随着人们对随机共振机理及其自适应算法研究的进一步深入，自适应随机共振技术将成为强噪声控制下的弱信号检测的一种新的技术。因此，系统地研究自适应随机共振技术并应用到实际测量中去，将是一项十分有意义的工作。更多还原

【Abstract】 Stochastic resonance (SR) is a new and very important embranchment in the nonlinear science field. SR system is a nonlinear system.Input the signal and noise into the system. With the noise being added to a proper value,the system will show shochastic resonance and enhance the output signal.The SR technology is better than the traditionary signal detecting method.The best virtue of it is using the noise to enhance the capability of detecting the weak signal. And it will not harm the signal at the same time.For the need of actual engineering signal detection,our project researched the physics mechanism of SR and extend it to the field of engineering application. We have studied the background of engineering detecting and adaptive SR technology,made a systemic research on the theory and drawn some conclusions from simulation. Then we designed an engineering-oriented adaptive stochastic resonance signal-detecting system.The main contents of the thesis are as following:1 . The introduction of the history,status and development of SR,and the statement of SR theory.2. The study of relationship among signal,noise and the nonlinear system,and the systemic conditions for shochastic resonance.3. The study of characteristics of the nonlinear system. Realization of the adaptive SR algorithm of detecting the characteristic information of practical weak signals overwhelmed in strong noise.4. The development of design scheme of adaptive SR signal-detecting system applied on the engineering spot. Realization of the system interface and software .The debugging and testing.5. The application of the system into broken-down signal -detected project of intermediate frequency switch electrical source and getting the satisfied achievement.With farther research into the SR mechanism and its adaptive algorithm,adaptive SR technology is becoming a new technology for detecting weak signals overwhelmed in strong noise. So that,to study adaptive SR technology and apply it into actual signal detecting will greatly make sense.更多还原