<title>Fluctuation-based technique for beamforming and auto detection</title>

Abstract

A technique is presented for generating a modified cross- spectral density matrix (CSDM) that is sensitive to fluctuations in the frequency bin amplitudes and phases of sinusoidal signals (plus noise) and noise. The beamformed output of such a fluctuation-based CSDM provides signal-to- noise ratio (SNR) gains in excess of those achieved using a conventional CSDM. The additional gains are inversely proportional to the beamformed ratio of the signal bin fluctuations to the noise bin fluctuations. An unalerted auto-detection capability is another advantage of this new technique.