There are two common algorithms based on natural gradient method

which are fix-step-size algorithm and adaptive step-size algorithm

respectively.Fix-step-size algorithm has a very fast convergence rate in the initial stage of Blind Source Separation.As iteration goes on

however

the step size gradually leads to poor robust performance.On the other hand

for adaptive method

the relatively small initial step size inevitably leads to more times of iteration.To further reduce the contradiction between convergence speed and convergence robust

as well as redundancy computation

two-segment method is therefore proposed in this paper.In addition

the adaptive step formula is modified by the related coefficient with high order.Computer simulation result confirms the effectiveness in improving convergence rate and robustness

as well as reduction of computation in BSS problem.