Sensitivity of a Passive Tracking Algorithm to Input Variations

Résumé du livre

The sensitivity of a passive horizontal-tracking algorithm to variations in input measurements is investigated. The algorithm determines estimates for depth, range, bearing, horizontal speed, course, and frequency for a cw acoustic source moving with constant velocity at fixed depth. The receiver is a horizontal linear array towed at a constant depth. Both source and receiver move in the upper portion of a deep ocean and are separated by a relatively short range. Dominant acoustic signals are presumed to arrive along two upper-ocean ray paths. The algorithm uses a new combination of input quantities, including multipath information, Doppler frequency shifts, and array directional measurements. Procedures are developed for analyzing effects of input-measurement errors on source localization. The robustness of the algorithm to small variations in acoustic measurements and environmental parameters is demonstrated for a variety of source-receiver configurations. Variance estimates of position and motion are obtained in terms of input-measurement variances. Bounds on tracker performance are developed for measurements that are affected by noise. Results from the several types of analyses corroborate the sensitivity characteristics of the algorithm. Additional keywords: Multipath propagation; Tracker sensitivity. *MSG RECEIVE.