Robust adaptive array beamforming with random error in cycle frequency

By exploiting the cyclostationary properties, the SCORE algorithms presente d by Agee et al. (1990) have been shown to be effective in performing adapt ive beamforming without requiring the direction vector of the desired signa l. However, these algorithms suffer from severe performance degradation in the presence of a random error in cycle frequency. The authors first establ ish a statistical model of the cyclic correlation matrix when the random er ror exists. According to this statistical model, two robust methods based o n the SCORE algorithms are developed to achieve robust adaptive beamforming against random error. Analytical formulas are then derived for evaluating the performance of the proposed methods. Several simulation examples are al so presented for confirming the theoretical analysis and showing the effect iveness of the proposed methods.