Joint identifiability of parameters of linear dynamic equations of a plant and disturbances

The problem of parametric identification of the object described by a system of linear difference equations in the presence of additive deterministic disturbances in the observations is considered. Disturbances are also described by linear difference equations of given order with uncertain initial conditions and coefficients. The necessary and sufficient conditions for the local co-identifiability of the coefficients of the object and the disturbances equations are obtained.