Double exponential inversionalgorithm based on differential evolution in photon correlation spectroscopy

In traditional double exponential inversion algorithm of photon correlation spectroscopy (PCS), four initial parameters choice of decay linewidths and decay linewidth distribution coefficients affect the particles size inversion accuracy. In order to obtain the optimal parameters, based on differential evolution algorithm, an optimization algorithm within the global is proposed. This algorithm begin from a solution set of four parameters, iteratively calculated by operation rules of differential, variation and choice, simultaneously perform survival of the fittest according to the objective function value of each solution and gradually guide the search process approaching the optimal solution. This algorithm overcomes difficult of iterative initial value choice By new algorithm and traditional algorithm, simulation datum with noise-free and noise of 100nm-500nm bi-dispersed particles were respectively inversed. The results show new algorithm has strong tolerance of noises, when the noise levels is within 0~0.001,compared with tradition algorithm, it can reduce inversion error by 0.31% ~ 2.52%. Therefore, new algorithm is effective double exponential inversion algorithm in particles size inversion of PCS.