Laurie T. Fialkowski
John S. Perkins
Michael D. Collins
W. A. Kuperman
Naval Res. Lab., Washington, DC 20375
John A. Fawcett
SACLANT Undersea Res. Ctr., 19038 La Spezia, Italy
Environmental source tracking (EST) is a matched-field processing (MFP) technique that exploits source motion in a complex environment [Collins et al., J. Acoust. Soc. Am. 94, 3335--3341 (1993)]. EST involves searching for a source track which provides the best agreement with the data. EST performed using a single receiver and a single frequency can often outperform conventional MFP methods with a fixed source and an array of receivers. In this paper EST performance is discussed, using a data set obtained in shallow water north of Darwin, Australia. In-situ acoustic data from a known source were used to invert for the environmental parameters. Parabolic equation solutions were then used to generate replica fields throughout the region. EST was performed for both radial and nonradial source tracks. In some instances, the source speed was reasonably constrained to eliminate very short tracks from the search space. The performance of several error measures is discussed. Improved EST results were obtained using multiple receivers and frequencies.