Some Lessons from Array Processing Theory

Practical problems arising in radar, sonar and seismology have stimulated extensive research in the area of array processing during the past two decades. This paper is not a review in the sense that it attempts to give a balanced presentation of the various elegant and highly mathematical analyses which have contributed to an understanding of arrays. It is the author’s feeling that array processing as a field has now matured to the point where a number of fairly simple intuitive notions can be abstracted from the more formal studies. We will be concerned with these intuitive notions, with questions like: What have we learned and why are these conclusions plausible? For formal proofs the interested reader will be referred to the, by now, very extensive literature.