基于参数非共振激励混沌抑制原理的微弱方波信号检测

利用自治混沌系统的参数非共振激励混沌抑制原理实现强噪声背景下微弱方波信号的检测. 将频率远大于系统特征频率的方波信号作为内置激励信号，经平均法处理后，得到受控系统与原系统之间的参数等效关系，并由此确定使系统由混沌状态突变为周期状态的检测参数临界值. 数值仿真结果表明此系统可以达到极低的信噪比工作下限. 相比于利用参数共振微扰混沌抑制原理实现微弱信号检测的有关方法，此方案可根据严格的理论分析得到更准确的检测参数估计值，有利于在相关领域推广应用. 关键词： 自治混沌系统 参数激励 方波信号 检测

Detection of weak square wave signals based on the chaos suppression principle with nonresonant parametric drive

Based on the principle of chaos suppression with nonresonant parametric drive in autonomous chaotic systems, detection of weak square wave signals in strong noise is realized. Firstly a square wave signal whose frequency is far higher than the system characteristic frequency is introduced as the system internal drive signal. According to the parametric equivalent relation between the controlled system and the original system obtained by the averaging method, the critical value of the detection parameter is determined, which marks the sudden change from chaos state to periodic orbit of the system. Numerical simulations show that extremely low signal-to-noise ratio limit in detection can be attained by the proposed system. Compared with the known weak signal detection methods based on the parametric resonant perturbation principle, this method gives more accurate estimates of the detection parameter through strict theoretical analysis, which enables its generalization and application in related fields.