ADAPTIVE HIGH RESOLUTION SPATIAL DISCRIMINATION OF PASSIVE SOURCES

Increased spatial resolution over conventional beamformer by adaptive arrays is limited by the weakness of signal to noise ratios usually available in passive listening. It is shown here that a more complete modelization of the noise field and particularly of the background noise spatial coherence allows to define an asymptotically infinite spatial resolution method by using an algebraic property of the spectral density matrix. Its robustness is checked against measurement noise and modelization errors. Results obtained from field records are presented.