地下工程环境下基于混沌系统的微弱磁共振信号提取方法研究

项目名称： 地下工程环境下基于混沌系统的微弱磁共振信号提取方法研究

项目编号： No.41504086

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 天文学、地球科学

项目作者： 易晓峰

作者单位： 吉林大学

项目金额： 21万元

中文摘要： 磁共振技术（MRS）作为一种水源信息直接探测方法，应用于地下工程水害隐患预报具有明显优势。但由于信号极其微弱，对工业用电、采掘设备等强电磁噪声干扰特别敏感，致使这种方法在隧道、矿井等环境中应用时受到限制。本项目针对磁共振技术在地下工程环境中难以获取有效信号的技术瓶颈，研究强噪声背景下基于混沌理论检测系统的微弱磁共振信号提取方法。在分析噪声特征与模型参数的约束关系基础上，确定关键参数的选取策略，建立适用于地下工程的混沌系统检测模型。针对信号幅值变化导致相图状态的不确定问题，提出适合于磁共振信号特征的拆解与重建算法，提高检测精度。同时，为抑制天线扰动对混沌系统灵敏度影响，开展固定参数的硬质接收天线研制，实现目标信号的有效检测。通过本项目的研究，能够实现-60dB信噪比下甚微弱磁共振信号的提取，将仪器系统的抗干扰能力提升到一个新的水平，为矿井、隧道中的水害隐患准确预报提供有力的技术支撑。

中文关键词： 磁共振探测；混沌检测系统；弱信号提取；水灾害隐患；地下工程

英文摘要： Magnetic resonance sounding (MRS) technology, as a method of direct detection for water information, has obvious advantages applying in water-inrushing hazard prediction in underground engineering. However, MRS signal is extremely weak and sensitive to strong electromagnetic disturbing from industrial electricity and mining equipment which leads to limiting the application of this method in the tunnels and mines. Aiming at the technological problem that MRS technology is difficult to obtain effective signals in the underground engineering, this project researches a method for weak MRS signal extraction against strong noise based on the chaos theory system. On the basis of analyzing constrained relationship between the noise characteristics and the model parameters, a selection strategy of key parameters is determined and a chaotic system suitable for underground engineering is constructed. Considering the problem that changes the signal amplitude leads to uncertainty of the state of phase diagram, dismantling and reconstruction algorithm suited to MRS signal characteristic is proposed to improve the detection accuracy. Besides, in order to suppress antenna disturbance to impact on sensitivity of chaotic systems, the stereoplasm receiving antenna with fixed parameters is researched to realize valid test of target signals. Through this project, the extraction of extremely weak MRS signals at SNR=-60 dB can be realized, which will increase the anti-interference ability of instrument systems to a new level and provides a powerful technical supporting for the accurate prediction of water-inrushing hazard in the tunnels and mines.

英文关键词： Magnetic Resonance Sounding;chaotic monitoring system;weak signal extraction ;water-inrushing hazard;underground engineering