A MINMAX APPROACH TO ADAPTIVE MATCHED-FIELD PROCESSING IN AN UNCERTAIN PROPAGATION ENVIRONMENT

Adaptive array processing algorithms have achieved widespread use beca use they are very effective at rejecting unwanted signals (i.e., contr olling sidelobe levels) and in general have very good resolution (i.e. , have narrow mainlobes). How ever, many adaptive high-resolution arra y processing algorithms suffer a significant degradation in performanc e in the presence of environmental mismatch. This sensitivity to envir onmental mismatch is of particular concern in problems such as long ra nge acoustic array processing in the ocean where the array processor's knowledge of the propagation characteristics of the ocean is imperfec t. An adaptive minmax matched field processor is formulated which comb ines adaptive matched field processing and minmax approximation techni ques to achieve the effective interference rejection characteristic of adaptive processors, while limiting the sensitivity of the processor to environmental mismatch. An efficient implementation and alternative interpretation of the processor are developed. The performance or the processor is analyzed using numerical simulations.