Dynamics of inhomogeneous one--dimensional coupled map lattices

We study the dynamics of one--dimensional discrete models of one--component active medium built up of spatially inhomogeneous chains of diffusively coupled piecewise linear maps. The nonhomogeneities (``defects'') are treated in terms of parameter difference in the corresponding maps. Two types of space defects are considered: periodic and localized. We elaborate analytic approach to obtain the regions with the qualitatively different behaviour in the parametric space. For the model with space--periodic nonhomogeneities we found an exact boundary separating the regions of regular and chaotic dynamics. For the chain with a unique (localized) defect the numerical estimate is given. The effect of the nonhomegeneity on the global dynamics of the system is analyzed.