Detecting Method of Weak Sine Signal with Initial Phase

Generally, the detecting signal methods based on the chaos theory always cope with the signal whose phase angle is zero. On this basis, this paper expands the method of chaos theory to the situation that the phase angle does not equal zero. According to initial phase angle of different detected signal, different driving force value automatically is set up. Output states of the system are detected from chaotic critical state to cycle state by automatically searching threshold value. Then make the system go back to chaotic critical state again by regulating the driving force value. Lastly, the amplitude and phase angle are solved by corresponding algorithm. This method can further perfect and supplement former methods. The simulation results indicate that this method can enhance the detecting performance of system and improve the measurement precision.