Survey technique for high-resolution ocean navigation

Abstract

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 employed to develop a maximum-likelihood estimator for mooring positions. An approximate covariance matrix of the estimate errors is generated, and an optimum choice of survey points is indicated. The combined system, using these selected locations for performing the survey, yields mooring coordinate errors of about ±1 m. Improved precision appears to be limited by inaccuracies in the pulse and Doppler measuring systems.

Ocean bottom control using the global positioning system

“…Position determination of marine control points, including performance analysis of acoustic navigation systems and net-unit configurations, is under extensive study by marine technologists (Knowles and Roy, 1972;Saxena, 1975;Durham et al, 1975;Yamazaki, 1975aYamazaki, , 1975bSmith et al, 1975;Spindel et al, 1975;Saxena et al, 1976 and1981). The typical high-resolution acoustic navigation technique considered here is a pulse positioning system (PPS).…”

Use of GPS in ocean‐bottom control

“…Position determination of marine control points including performance analysis of acoustic navigation systems and net-unit configurations is under extensive study with the marine technologists (Knowles and Roy, 1972;Saxena, 1975;Durham et al, 1975;Yamazaki, 1975;Smith et al, 1975;Spindel et al, 1975;Saxena, 1976 and1981). The typical high resolution acoustic navigation technique considered here is a pulse positioning system (PPS).…”