Ocean acoustics, sonar array processing, acoustic telemetry of the ocean and matched field array processing.
Navigation and mapping for autonomous mobile robots, robotic localization and mapping applications below, on and above water in marine and river environments.
Ocean exploration, remote sensing of marine life and geophysical phenomena, census of marine life, ocean acoustics, and hurricane classification.
Research interests are in the general area of signal processing and its applications: coauthor of the widely used textbooks Discrete-Time Signal Processing and Signals and Systems.
Arctic and shallow water acoustics; scattering and reverberation due to sea surface and ice roughness; determination of seismic-acoustic propagation and reverberation in ocean environments; and 3-D acoustics in very shallow water.