Method and apparatus for operating an exhaust gas aftertreatment system of an internal combustion engine

In a method and an apparatus for operating a particulate filter having exhaust aftertreatment system of an internal combustion engine, particularly a motor vehicle, wherein at least one characteristic of the loading state of the particle filter size of operating parameters of the particle filter is determined, is to achieve an increased accuracy of the load determination of the particulate provided that essentially models the spatial distribution of exhaust particulates in the longitudinal direction of the particulate filter and a correction of the characteristic quantity is carried out by means of the modeled spatial distribution of the exhaust particles.