An adaptive coupled range-dependent normal-mode method

Based on the warping method and the generalized eigenvalue problem the range-independent solution is extended to that of range dependence. In this method, coupling in range is analytical and may be either one way or two way. Since the range steps are not dependent on finite-difference schemes, the optimal range step at each point is determined. This leads to two advantages: (1) There is no need for input of range step; and (2) the optimal range step is predetermined by several conditions, thus avoiding overkill and reruns to determine stability. Comparisons with other range-dependent methods are presented. [Work sponsored by ONR, the Naval Res. Lab., and the Univ. of New Orleans.]