耦合映射混沌同步系统在加性噪声中的筛形域性态

由于实际系统中噪声不可避免，噪声使得同步混沌吸引子A变成具有一定生存时间<τ>的准稳态吸引子A′.以加性噪声作用下的二维耦合映射混沌同步系统为例，给定系统实验时间长 度T，解析发现：仅当<τ>>2T时准稳态同步混沌吸引子的筛形吸引域才可被定性观察到；而 当<τ><2T时则不复存在，此时，根据原无噪声时的筛形吸引域特征的不同，筛形域不仅可 以转变成时变筛形结构，还可以转变成分形结构.同时利用数值模拟作了进一步验证.该结果 对于二维耦合映射混沌同步系统具有普遍意义. 关键词：混沌同步筛形吸引域瞬态混沌耦合映射加性噪声

The characters of riddled basins in coupled chaotic synchronized maps with addit ive noises

In real systems, because of the inevitable noise, a chaotic synchronized attractor A will turn into a metastable attractor A′ with an average lifetime <τ>. We analyze a two-dimensional coupled map with additive noises and find analytica lly that the riddled basin of A′ will disappear when <τ><2T and can only be ob served qualitatively when <τ>>2T, where T is the duration of an experiment. Acc ording to the characters of the riddled basin without noises, it is found that t he riddled basin will turn into not only a temporal riddled basin but also a reg ular fractal basin. This result is universal in two-dimensional coupled chaotic synchronized maps, and the further numerical calculations can also confirm this point.