Suprathreshold Stochastic Resonance in a Single Comparator

Stochastic resonance usually appears when stimulus is too weak to overcome barriers in a nonlinear system. Unusually, we demonstrate that in a simple competitor as a prototype model, stochastic resonance can still occur when the stimulus is predominantly suprathreshold. This result provides new knowledge for understanding of mechanism underlying information process in biological systems and aIso finds appfications in signal processing.     

Frequency Resonance in Stochastic Systems

The phenomenon of frequency resonance,which is usually related to deterministic systems.is investigated in stochastic systems.We show that for those autonomous systems driven only by white noise,if the output power spectrum exhibits a nonzero peak frequency,then applying a periodic signal just on this noise-induced central frequency can also induce a resonance phenomenon,which we call the frequency stochastic resonance.The effect of such a resonance in a coupled stochastic system is shown to be much better than that in a single-oscillator system.     

Experimental Analysis of Stochastic Resonance in a Duffing System

An experimental circuit is used to study the stochastic resonance(SR) phenomena in a Duffing system.The charcacteristics of SR are investigated from various aspects by varying all the possible parameters,The deviations between the experimental results and the adiabatic theory are presented.     

Stochastic Resonance in a Bistable Sawtooth Potential Driven by COrrelated Multiplicative and Additive Noise

We Present and analytical investigation of the signal-to-noise ratio(SNR)by studying the bistable sawtooth system driven by correalted Gaussian white noise.The analytic expression of the SNR is obtained.We detect some novel results,as follows.(1) Stochastic resonance(SR) always occurs in the SNR-Q (the multiplicative noise intensity)curve for the whole range of correlation coefficients.(2)There is not only resonance but also suppression and monotony in the dependence of SNR upon the additive noise intensity.(3) There are two extrema(one is minimum,the other meximum)in the SNR-b(the barrier height)curve for different multiplicative noise intensities.     

Resonance in Defect Turbulence under Periodic External Force

The periodically forced spatially extended Brusselator is investigated in the chaotic regime. We explore resonant or non-resonant patterns generated under various forcing frequencies and forcing amplitudes. Resonant spatially uniform oscillation and irregular structures are found. Furthermore two types of regular spatial patterns are generated under appropriate parameters. Our results of numerical simulations demonstrate that periodic force can give rise to resonant patterns in forced systems of spatiotemporal chaos similar to the situation of forced systems of regular oscillations.     

Enhancement of Information Transmission by Array Induced Stochastic Resonance in the Processes of Amplitude and Frequency Modulations

Information transmission is studied in the cases of amplitude and frequency modulations where there is an impulsive jamming in the signal. By using the array approach of nonlinear elements, we find that for both the periodic and aperiodic modulations, the information transmission can be enhanced by adding independent external noise on every element of the array. The dependence of information transmission on the size of array and the impulsive interval of the jamming are also studied.     

Stochastic Resonance in an Asymmetric Bistable System Subject to Frequency Mixing Periodic Force and Noise

The phenomenon of stochastic resonance (SR) in an asymmetric bistable system subject to the multiplicative and additive white noises and two periodic fields is investigated. Using the two-state theory, analytic expressions of the signal-to-noise ratio (SNR) for fundamental harmonics and higher harmonics are derived. It is found that SR appears at both fundamental harmonics and mixed harmonics (of second- and third-order approximation).Moreover, the higher the order of mixed harmonics is, the larger the SNR values are. The effects of static asymmetry on the SNR (of second- and third-order approximation) are different, and the noise intensity ratio can enhance the SNR for higher harmonics.     

Frequency （Stochastic） Resonance and Stochastic Resonance for a Superconducting Junctions＇ Device

In this paper, we investigate a Josephson-junction device with dichotomous resistance or a special SQUID （superconducting quantum interference device）. It is shown that frequency （stochastic） resonance and stochastic reso- nance can appear for some suitably selected parameters＇ values of the device respectively. Our results can provide some insights for the investigation of the SQUID response to the signal （including the input alternating current, the added al- ternating voltage, the vertically added alternating magnetic field, and the detected （electric-magnetic） temporal-periodic signal）.     

Stochastic Resonance in a Single-Mode Laser Driven by Quadratic Colored Pump Noise： Effects of Biased Amplitude Modulation Signal

A single-mode laser noise model driven by quadratic colored pump noise and biased amplitude modulation signal is proposed. The analytic expression of signal-to-noise ratio is calculated by using a new linearized procedure. It is found that there are three different typies of stochastic resonance in the model： the conventional form of stochastic resonance, the stochastic resonance in the broad sense, and the bona fide SR.