对称Alpha稳定分布噪声下的Duffing振子检测方法  

Detection method of the Duffing oscillator under symmetric Alpha-stable noise

作　　者：李楠[1,2,3] 李秀坤[1,2] 刘彩虹 

机构地区：[1]哈尔滨工程大学水声技术重点实验室,哈尔滨150001 [2]哈尔滨工程大学水声工程学院,哈尔滨150001 [3]东北电力大学信息工程学院,吉林132012

出　　处：《船舶力学》2017年第1期90-98,共9页Journal of Ship Mechanics

基　　金：国家自然科学基金资助项目(51279033);黑龙江省自然科学基金资助项目(F201346)

摘　　要：Duffing振子是利用系统对与策动力同频的小信号敏感而对噪声免疫实现微弱信号检测,特定分布下的噪声激励Duffing振子系统不会发生相变是应用该方法的前提条件。文中主要研究了服从Alpha稳定分布的噪声激励Duffing振子产生相变的鲁棒性问题,研究结果表明Duffing振子相变在Alpha稳定分布源的激励下为小概率事件。为消除小概率相变的影响,利用多支路并行检测及多数判决准则对常规的Duffing振子检测方法进行改进,即将待测信号分段截短周期延拓后送入多个并行Duffing振子检测单元,若检测单元多数发生相变,必然是由于弱目标信号而非噪声激励所致,即可判定检测信号中包含目标小信号。将该方法应用于水下目标回波信号的检测中,实测数据处理结果验证了该方法是有效的。Duffing oscillator own the property of sensitivity to small signal and immune to noise, which can be used to detect weak signal. The precondition of applying this method is that the phase motion of the system does not transit by excitation of the noise under the specific distribution. Duffing oscillator subjected to excitation by noise under symmetric Alpha-stable distribution, the robustness of the phase-state transition is studied. The simulation results show that the phase-state transition of the system is a small probability event. In order to eliminate the effect of small probability event, a multi-branch parallel detection method of the Duffing oscillator is proposed. The measured signal is truncated and periodic extended, then processed signals are sent to multi-branch parallel detection units. If phase state of the most branches transit in large periodic state, it is due to the excitation of small target signal rather than the noise. Namely, the detected signal contains the target signal. The proposed method is applied to the detection of underwater target echo signals, and the results show that this method is effective.

关 键 词：DUFFING振子 对称Alpha稳定分布 小概率事件 多支路并行检测 

分 类 号：U661.1[交通运输工程—船舶及航道工程]