Space-time adaptive processing in modern electronic warfare environments

Extensive investments have made toward the development of adaptive array technology for airborne early warning (AEW) radar applications. A characteristic common to all AEW space-time adaptive processing (STAP) approaches designed to operate in a nonhomogeneous interference environment is that they require an estimate of the statistics of that environment based upon measured data from within the multi-dimensional cancellation space. The signal models on which most STAP schemes are based rely upon the assumption of independent and identically distributed (i.i.d.) reference data. Non-conventional ECM environments can severely alter the i.i.d. assumption, especially over extended sampling windows in range. For a radar system designed to rely upon relatively high cancellation performance, target detection capabilities can be severely degraded. We characterize adaptive array radar performance in such a non-conventional ECM environment.