AN EFFECT OF RANGE-HETEROGENEOUS CLUTTER ON ADAPTIVE DOPPLER FILTERS

The practical implementation of adaptive Doppler Alters requires estimates of clutter parameters to determine the adaptive weights. One method of deriving the estimate is via the sample matrix inversion (SMI) algorithm using multiple data snapshots from adjacent range cells. For homogeneous clutter environments, this technique gives performance that asymptotically approaches the optimum (a priori known covariance matrix) as the number of snapshots approaches infinity. It is shown that this asymptotic behavior does not occur for heterogeneous clutter environments. An equation for the decrease in improvement factor is derived. To ease the development of understanding, the simplified special case of narrowband clutter is considered in detail. It is shown that in almost all cases the loss is small. © 1990 IEEE