An exhaust gas treatment device for an exhaust gas system of an internal combustion engine, in particular of a motor vehicle, includes a housing and at least one exhaust gas treatment insert arranged in the housing and sheathed by bearing material on the circumference. A consumable dosage delivery unit includes a dosage form and a bio-compatible wireless communications tag. The second waveguide includes a first layer with a first predetermined refractive index andor first predetermined thickness, a second layer with a second predetermined refractive index andor second predetermined thickness. The spatial correlation matrices from the sub-arrays are averaged, and the averaged spatial correlation matrix is used as input to an adaptive array processing algorithm.