Linearized travel time, intensity, and waveform inversions in the ocean sound channel—A comparison

Linearized inversion schemes involving waveform (total record), intensity (dephased total record), and travel times (intensity peaks) are used on synthetically generated arrival patterns to solve for the sound speed structure in the upper km of a range-independent ocean model. In all three cases inversions are carried out for a variety of source center frequencies and bandwidths. The results are compared; conditions under which each inversion method performs poorly and well are outlined. The nature of the linearization approximation is discussed for each of the three types of inversion scheme as well as the methods used to solve the general linearized system.