Application of multitaper methods to passive sonar

Abstract

While the multitaper spectral estimation method [Thomson, Proc. IEEE 70, 1055–1096 (1982)] is used extensively in time series analysis, it has received much less attention in the array processing literature. The multitaper approach reduces the variance of power estimates by averaging windowed Fourier transforms of the data obtained using a set of orthogonal window functions. One advantage of the multitaper method is that it is designed to work with low sample support. Since multitaper estimates are often formed using a single data snapshot, they are suitable for use in highly nonstationary environments where it is difficult to obtain reliable estimates of the noise and interference statistics. This talk focuses on the application of the multitaper method to the passive sonar array processing problem. Standard techniques exist for detecting the presence of line components using multitaper estimates. This talk describes how to extend these techniques to detect plane waves in sonar data, where the signals are typically modeled as complex Gaussian rather than deterministic. Processing of non‐plane‐wave signals, e.g., normal modes, will also be briefly discussed. [Work supported by an ONR Young Investigator Award.]