In Daum (1992) it has been very well explained that sensor resolution modeling is crucial for the tracking of closely spaced targets. For non-maneuvering targets appropriate models and tracking approaches have been developed by Chang & Bar-Shalom (1984) and by Koch & Van Keuk (1997). This paper combines their sensor resolution submodels with a descriptor system approach towards tracking two suddenly maneuvering closely spaced targets from measurements that may be false, missing or unresolved. Using this descriptor system formalism, exact Bayesian and approximate filter equations are derived.