Study Of Weak Signal Detection Approaches Based On Chaos Theory

The weak signal can be detected by chaotic oscillator owing to its property ofsensitive dependence on initial conditions and of immunity from noise. This paperanalyzes the basic form of Duffing equation and the chaotic motion of the Duffingoscillator, and then describes the principle of weak signal detection based on thechange of phase trace. The frequency difference condition of the intermittent chaoshappening and the effect of phase difference on system performance are deduced.The simulation model applicable to signal detection of sine wave,square wave andarbitrary periodic signals is given. Afterwards, with these models, lots of simulationexperiments are done. Improved methods to detect frequency, phase and amplitudeare put forward. Finally, the principle of correlation detection and new methods forweak signal detection based on combining correlation function with chaos theoryare introduced;simulation model, frame diagram and simulation results are given.