Robust maximum energy adaptive matched field processing

Adaptive array processing algorithms have achieved widespread use because they are very effective at rejecting unwanted signals (i.e. controlling sidelobe levels) and in general have very good resolution (i.e. have narrow mainlobes). However, many adaptive high-resolution array processing algorithms suffer a significant degradation in performance in the presence of environmental mismatch. This sensitivity to environmental mismatch is of particular concern in problems such as acoustic array processing in the ocean where the array processor´s knowledge of the propagation characteristics of the ocean is usually imperfect. A maximum energy matched field processor is formulated which “tunes” the replica vector used by a minimum variance distortionless response (MVDR) matched field processor to adjust for fluctuations in the environment. The resulting processor has the same structure as the two-stage MVDR processor interpretation of the adaptive minmax matched field processor proposed previously. However, the criteria which the two processors use to “tune” replica vector differ. The result is that the MEMV processor achieves a level of performance superior to that of the adaptive minmax processor and close to that of traditional adaptive processors while limiting the sensitivity of the processor to environmental mismatch. An algorithm for implementing the professor is developed, and the performance of the processor is analyzed