Colored diagonal loading

We develop a beamforming technique called colored diagonal loading. This technique is a generalization of diagonal loading in which the covariance matrix is augmented with a scaled version of a colored matrix as opposed to using the identity matrix as with conventional diagonal loading. Thus as the loading is increased, the beampattern increasingly takes on the form of a desired quiescent pattern as opposed to that of a conventional (high sidelobe) pattern. The attractiveness of this technique is that it retains the robustness and simple formulation of diagonal loading while allowing insertion of additional quiescent structure. We compare this technique is to conventional diagonal loading and to other quiescent pattern techniques.