TABLE OF CONTENTS Ulrich Nickel
Broadband superresolution and interference suppression have been topics of intensive research since the early 1980s. At that time the pioneering work of Schmidt appeared [1] and a broad literature on adaptive arrays was already available [2]. It is impossible to summarise all the work that has been published since then in a few pages. Therefore, we focus here on special aspects of the problem.
The intention of this chapter is to give a fairly compact overview of some of the key ideas on broadband superresolution and interference suppression which are applicable for the special case of a multifunction radar. There is always a request for performance enhancements leading to arrays with larger bandwidth. In particular for airborne radar, there is a great interest in providing a search and track radar with an additional target recognition feature by high range resolution or with an additional imaging mode based on SAR (synthetic aperture radar) processing. The typical feature of a multifunction radar is that it has a high gain antenna, which means an array antenna which consists of thousands of elements. The array elements are summed up in analogue technology into subarrays which are further processed digitally. Our main interest is to point out in which way we can extend the usual narrowband processing with such a complicated array to broadband applications. We will therefore consider in particular simple cost-effective methods. Sophisticated methods that...
