Chaotic systems have certain ability to suppress noise and are sensitive to initial conditions. Therefore,in weak signal detection,compared with the traditional detection method chaotic system has a great advantage. In this paper,a new type of Lorenz-like chaotic system is improved,and the improved system is made more sensitive to sinusoidal signal amplitude changes by adding periodic perturbations to meet the conditions of detecting weak periodic signals. At the same time,a 0-1 test algorithm is introduced to further confirm the threshold value of the chaotic state of the system,so that the accuracy of the improved system in detecting the amplitude of weak signals can reach 10-4 V. The detection of unknown frequency signals is realized by calculating the variance of the state variables. Simulation results show that the chaotic system can detect the lowest signal-to-noise ratio up to-63.01 dB.
关键词
混沌/类Lorenz系统/弱信号检测/信噪比
Key words
chaos/Lorenz-like system/weak signal detection/signal-to-noise ratio
维普
万方数据