Coverage metric for acoustic receiver evaluation and track generation

Acoustic receiver track generation has been the subject of active research, both academic and operational, since at least 1946. In general, track generation algorithms operate by maximizing some measure of effectiveness or performance for a particular receiver in a particular environment. Current probability-based receiver performance measures are difficult to visualize, time consuming to calculate and are not easily subject to strict scientific analysis. Although great strides have been made in the ability to model and predict oceanography (temperature, salinity, currents, etc.) accurately, there exists the need to develop measures of receiver performance which more readily lend themselves to analysis of sensitivity to environmental variation or uncertainty. With the increasing dependence on optimization algorithms in acoustic receiver placement and track generation in the presence of variable or uncertain environments, the desire for a more environmentally-sensitive metric of acoustic receiver performance has arisen. A measure of performance based upon acoustic coverage area has shown promise as a basis for acoustic receiver utilization and optimized track generation applications and is presented here. Coverage can be defined as the areas throughout which a receiver has a sufficiently high signal-to-noise ratio or, alternatively, probability of making positive observations. For the purposes of determining optimal receiver placement and track generation the area of interest is divided into a sufficiently sampled grid of calculation points. Computing and compiling acoustic receiver coverage area information for grid points throughout the area of interest into an acoustic receiver coverage map gives immediate visual feedback on locations of optimal performance for a specific acoustic receiver in use in the current ocean environment. By making use of multiple calculation layers in an N ? 2-D fashion, acoustic coverage volumes can be constructed for the purposes of thr- ee dimensional receiver placement or track generation. The use of an acoustic coverage-based metric for optimal track generation is shown to compare favorably with current track optimizers which use cumulative probability measures of performance, offering faster calculation times and a stronger connection to the acoustic environment.