1/fαnoise from self-organized critical models with uniform driving

Using the well-known Olami-Feder-Christensen model as our paradigm, we show how to modify uniform driven self-organized critical models to generate ${1/f}^{\alpha }$ noise. This model can reproduce all the main features of ${1/f}^{\alpha }$ noise: (1) $\alpha$ is close to one and does not depend on the dimension of the system. (2) The ${1/f}^{\alpha }$ behavior is found for very low frequencies. (3) The spatial correlations do not obey a power law. That proves that spatially extended systems based on activation-deactivation processes do not have to be point-driven to produce ${1/f}^{\alpha }$ noise. The essential ingredient is a local memory of the activation-deactivation process.