Detection of the pulse signal at low signal-to-noise ratio (SNR) is difficult but meaningful. Some documents have already used coupled Duffing oscillators to detect non-periodic pulse signal, but those oscillators have a few defects. This Letter presents a type of strong coupled Duffing oscillators system, and by using the generalised time scale transformation, the system can detect signal with any sampling frequency. The system is coupled by damping force and restoring force of the oscillators and has characteristics of high synchronisation speed and high coupling degree. The simulation results show that the system can detect large amplitude signal, large time-width pulse, and plus-minus signal, and the detection SNR is lower than −27 dB.

Signal denoising is an important aspect of signal processing. It is a meaningful direction to solve this problem by using chaotic oscillator. As a kind of chaotic oscillator, Duffing oscillator is often used in the field of periodic signal or pulse signal detection, but it has not been used in signal denoising. In this paper, a new Duffing oscillators system for signal denoising is proposed. The system utilizes the coupling between linear and nonlinear restoring forces of the oscillators to achieve complete synchronization of the system. Because the external signal will cause a large deviation of the oscillator's trajectory, while the Gauss white noise will only produce a small deviation. Based on this phenomenon, signal denoising can be realized. The simulation results show that, compared with the existing technology, our method is effective for the denoising of complex irregular signal, and can recover the mutation points of signal well. This method has less computational complexity and is easy to implement parallel computation. It can be used in real-time signal processing.

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