Trade-Off between Bandwidth and Number of Array Elements in the Performance Enhancement of Passive Fathometer

Jahangir Alam, E. H. Huntington, M. R. Frater

School of Engineering and Information Technology, University College, University of New South Wales, Canberra, Australia.

DOI: 10.4236/oja.2013.32A003                

Abstract

Improved signal to noise ratio (SNR) and resolution of the ambient noise cross-correlation function (NCF) between two points help in the estimation of bottom profile of the ocean. One of the main requirements of the improvement of the SNR and resolution is collection of a large amount of data. These large amounts of data can be achieved by recording a large bandwidth ambient noise or using an array of hydrophones. This paper evaluates the performance of the array processing and compares it to the large bandwidth technique in terms of SNR and resolution of NCF. It is shown that the large bandwidth technique gives better SNR and resolution compared to the array processing technique under certain conditions. The outcome of this article finds application in the enhanced estimation of the passive fathometer.

Keywords

Passive Fathometer; Cross-Correlation; SNR; Resolution; Bandwidth; Array Processing

Conflicts of Interest

The authors declare no conflicts of interest.

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