Survey technique for high‐resolution ocean navigation

We have reported on an acoustic Doppler navigation system for ocean use in several publications [R. P. Porter, R. C. Spindel, and R. J. Jaffee, J. Acoust. Soc. Am. 53, 1691–1699 (1973); R. C. Spindel, R. P. Porter, and R. J. Jaffee, J. Acoust. Soc. Am. 56, 440–446 (1974)]. The system can yield navigation fixes with respect to a bottom‐moored, continuous‐wave, beacon net with accuracies (on a fix‐to‐fix basis) of a few centimeters. The system has found use in generating synthetic space‐time acoustic apertures where it is necessary to track a receiver to within a fraction of an acoustic wavelength. In order to use the system to best advantage, a survey is required to determine precisely the relative positions of the beacons forming the net. We report here on a navigation system that combines a pulse transponder with a beacon to improve survey accuracy. It measures acoustic travel time between survey platform and mooring, as well as accumulated phase between survey points. Nonlinear regression techniques are...