Application of Array Processing for Parallel Linear Recursive Kalman Filtering in Underwater Acoustic Exploration

In underwater seismic exploration applications using acoustic arrays, the firing pulses suffer from air bubbles due to sudden change in water pressure. In practice, the optimum wave form is obtained after the firing pulse has travelled for about 50 meters in the water column. The wave-form is non-periodic and may be approximated by a damped sinusoidal wave. The wave hits the seabed and propagates through the ocean floor. The exploration task is to obtain information in real time from the reflected signals collected by a number of acoustic receivers. Several recent contributions to the literature on signal processing, computer architecture, and VLSI design show that systolic array processing techniques are extremely useful for designing special purpose devices to solve problems in linear algebra and system analysis. In this paper,we apply Kalman filtering theory and parallel Kalman filters to the exploration problem. Particular emphasis is given to the multi-receiver case as an important application of array processing methodology.