Adaptive matched beam processing for source localization

Abstract

Matched beam processing (MBP) has been previously applied to a horizontal line array for localizing a moving source in bearing and range, and for differentiating a submerged target from a surface clutter [T. C. Yang and T. Yates, J. Acoust. Soc. Am. 104 (1998)]. MBP is matched field processing in the beam domain. Using the Bartlett processor, bearing and depth resolutions are often inadequate for rejecting surface clutter and other noise sources. High-resolution processors may be required. We note that in situations where many clutters exist, adaptive (plane-wave) beamforming has effectively rejected clutter by either high-angular resolution or by steering a null to the interference source. Motivated by this approach, an adaptive MBP will be investigated in this paper. The new processor will apply adaptive beamforming to the data and replica fields such that interference has already been removed before the matched field correlation. This approach differs from the adaptive matched field processing where interference remains in the data field. The latter approach is known to be sensitive to environmental mismatch, as a result the correlation between the replica and the interference fields may be present as substantial clutter. Initial numerical results will be presented using simulated data with interference sources. [Work supported by the Office of Naval Research.]