A new method for simulating underwater acoustic signals in range dependent environments is presented, and the approach utilizes Maslov asymptotic theory as developed by C. H. Chapman for synthetic seismograms. The simulated range dependent signals are then used in active underwater acoustic tomography exercises, where changes in observed acoustic transmissions are inverted to obtain information about ocean sound velocity structure. The inversions are performed with both the generalized inverse and the maximum entropy inverse, and a new numerical method for finding the maximum entropy inverse with noisy data is presented. The numerical technique follows the ε statistic approach proposed by Bryan and Skilling.
