Performance Analysis of Large Adaptive Sidelobe Canceller Arrays with Reused Elements.

摘要

This report considers adaptive sidelobe canceller arrays (SLCs) in which the mainbeam and auxiliary signals are obtained from the same set of elements. The SLC with element reuse is different from the conventional SLC in that thermal noise components of the mainbeam and auxiliary signals are correlated. This correlation causes sidelobe degradation when the number of degrees of freedom exceeds the number necessary to cancel a given jammer scenario. The equations for a general planar array with an arbitrary signal scenario are first formulated. These equations are then used to examine array performance with different auxiliary configurations. Both auxiliaries form from a single array element and auxiliaries form from subarrays of elements are studied. Various auxiliary configurations are investigated to determine how the auxiliaries should be chosen to provide good cancellation of multiple jammers while retaining low sidelobes in the mainbeam. It is shown that using single-element auxiliaries may result in serious SLL degradation whenever there are extra degrees of freedom. This degradation can be overcome by using subarray auxiliaries that satisfy an orthogonality condition on their patterns. Excellent cancellation and sidelobe level performance can be attained with small subarrays chosen to satisfy this orthogonaltiy condition. (RRH)