Application of the L-curve technique to loading level determination in adaptive beamforming

Diagonal loading is a well-known technique in adaptive beamforming for adding robustness to mismatch. Effective use of this technique, however, requires that the loading level be properly set for the given environment. A technique called the L-curve, has been developed in the numerical linear algebra community for selecting the regularization parameter in least squares problems. Motivation for the L-curve is developed herein. This technique is applied to adaptive beamforming and its performance is evaluated through Monte Carlo simulation. Initial results indicate that the L-curve predicts the optimal loading level very well.