ABSTRACT
NHD Test Statistic........................................................... 192
3.2.4. Performance Analysis.................................................................... 194
3.2.5. Conclusion ..................................................................................... 204
An important issue in space-time adaptive processing (STAP) for radar target
detection is the formation and inversion of the covariance matrix underlying the
clutter and interference. Typically, the unknown interference covariance matrix
is estimated from a set of independent identically distributed (iid) target-free
training data that is representative of the interference statistics in a cell under test.
Frequently, the training data is subject to contamination by discrete scatterers or
interfering targets. In either event, the training data becomes nonhomogeneous.
Consequently, it is not representative of the interference in the test cell. Estimates
of the covariance matrix from nonhomogeneous training data result in severely
undernulled clutter. Consequently, CFAR and detection performance suffer.
Significant performance improvement can be achieved by employing preproces-
sing to select representative training data.
