A deterministic (non-stochastic) low frequency method for geoacoustic inversion.

摘要: It is well known that multiple frequency sources are necessary for accurate geoacoustic inversion. This paper presents an inversion method which uses the low (LF) spectrum only to estimate bottom properties even in presence of expected errors source location, phone depths, and ocean sound-speed profiles. Matched field processing (MFP) along a vertical array used. The LF first conducts exhaustive search (five) parameter space (sediment thickness, at top sediment layer, layer gradient, half-space sound-speed, water depth) 25 Hz continues by retaining high MFP value combinations. Next, slowly increased while again At each stage process, those combinations give values all previous predictions considered (an ever shrinking set). important note complete relevant seems be not (sequential) frequencies but also ranges order eliminate sidelobes, i.e., false solutions. Even so, there no mathematical guarantees one final, unique “solution” will found.