Identification of low-SNR Coulter signals based on strongly coupled Lorenz-like oscillators

Abstract

Abstract A Coulter prototype experiment is established and innovatively combined with coupled Lorenz-like oscillators to identify low-signal-to-noise ratio (SNR) Coulter signals. Coulter signals are collected by a Wheatstone bridge and fitted by Gaussian pulse signals. Using numerical simulation, low-SNR Gaussian pulses are added to the oscillators, and the synchronization mutation phenomena in the chaotic oscillators performed by the time scale transformation are analyzed. The maxima in the phenomena are used to detect the low-SNR pulses and construct an identification formula for different particle sizes. The nonlinear circuit of the oscillators is designed and fabricated. Then, it is applied to process low-SNR Coulter signals in the experiment. By selecting the maxima in the output signals from the circuit, according to the identification formula containing the correction coefficient, the particle size distribution can be obtained. The nonlinear circuit can effectively process low-SNR Coulter signals, which provides a good foundation for reducing the lower limit of detection in Coulter signals.