Linear frequency modulated signal induced aperiodic resonance

A method is proposed to induce strong aperiodic resonance in a linear frequency modulated signal excited nonlinear system. The phenomenon has application value in weak linear frequency modulated signal enhancement. The spectral amplification factor is used to measure the aperiodic resonance performance. By piece-wise analysis, appropriate system parameters are found. Then, a strong resonance output is achieved. The cross-correlation coefficient between the input and the output is another measurement of aperiodic resonance. However, there is a weakness in analysis of the linear frequency modulated signal. To overcome the shortness, a modified cross-correlation coefficient is proposed. As a result, the error of the cross-correlation coefficient induced by the phase difference of the excited signal is eliminated. In addition, by adding another much faster excitation, aperiodic resonance is further enhanced by vibrational resonance. (paper)