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Stochastic Resonance. Adding Noise to a signal can help in its detection. Just the right amount of noise must be added (resonance) SR in Nature Periodic ice age prediction Crayfish warnings of approaching bass - a periodic fin motion Dogfish spit noise to better detection. Neurons.
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Stochastic Resonance • Adding Noise to a signal can help in its detection. • Just the right amount of noise must be added (resonance) • SR in Nature • Periodic ice age prediction • Crayfish warnings of approaching bass - a periodic fin motion • Dogfish spit noise to better detection. • Neurons
Stochastic Resonance • What Causes SR? • Non-Additive Noise • Nonlinearities • Mathematical Definition • There is none
Example: Miyamoto Resonance Add noise to image and threshold. Vary noise. 0 15 30 60 90 120 180 240
dx/dt x 1/s ax-bx3 + + sin(t) (t) Most Studied System
Comparison of NP Optimal Detector • Coherent NP Correlator vs. Stochastic Resonance • Assumptions • Compared NP on input and after SR nonlinearity • Detector COHERENT • Noise = White Gaussian Galdi, Pierro, Pinto (Phys Review E, June 1998).
Comparison of NP Optimal Detectors • Coherent NP Correlator vs. Stochastic Resonance (4 dB) Galdi, Pierro, Pinto (Phys Review E, June 1998).
Noncoherent • Noncoherent SR sign detector Galdi, Pierro, Pinto (Phys Review E, June 1998).
Noncoherent Results • Noncoherent correlator is about 3dB worse than coherent. • Noncoherent SR is better than noncoherent correlator for low SNR Galdi, Pierro, Pinto (Phys Review E, June 1998).