The blind harmonic signal extraction algorithm based on the steady-state point capture under the chaotic background

The key issue to verify the confidentiality and guarantee the security of the system is to extract the harmonic signal accurately under the chaotic background. The energy distribution of chaotic signal will affect the extraction of harmonic signal. Based on the background of three typical chaotic dynamic systems, this article analyses their spectrums and finds the energy concentrated area. We propose the solution of capturing chaotic system steady state point by solving the Lyapunov exponent and design a novel blind extraction algorithm of harmonic signal based on the capture of parameter iteration steady point. By comparing the simulation results, this algorithm can accurately extract the harmonic signals under the three typical chaotic backgrounds and provide an effective method for the safety verification of the chaotic secure communication system.