Synthetic aperture towed-array processing: The Edmund J Sullivan Legacy

Dr. Edmund J. Sullivan developed synthetic aperture towed-array processing. Confronted by many nay-sayers Dr. Sullivan persisted with his work and developed the first approach as the signal processing group leader (SPGL) at the SACLANT ASW Center (now CMRE) in La Spezia, Italy. The first notional passive synthetic aperture processor using an overlapped correlation method was jointly developed [“Extended Towed Array Processing by Overlapped Correlator,” (JASA, 1989)]. This idea was to blossom even further in his collaborative works (Stergiopolous et al.) extending these ideas to a fully, recursive (in-time) model-based passive-synthetic aperture processor [“Space-time array processing: A model-based approach” (JASA, 1997)]. He also began collaborations with the Swedish Navy where he performed joint experiments in model-based passive synthetic aperture evaluating its performance in the ocean and demonstrating its effectiveness. Dr. Sullivan began mentoring more researchers and teaching at the University of Rhode Island where he advised students in underwater acoustics and processing leading researchers to the model-based approach (Cousins), synthetic aperture processing (Edelson) [“On the performance of the overlap-correlator synthetic aperture technique” (JASA, 1991)] and broadband processing (Holmes) [“Broadband passive synthetic aperture” (JASA, 2006) ]. His ideas were summarized in his recent text, [Model-Based Processing for Underwater Acoustic Arrays (Springer, 2015)].