Arrays and array processors: future real time applications in oceanography and sonar

Abstract

In the last several years oceanographic applications of arrays have increased substantially. The spatial resolution and redundancy provided by arrays have been necessary in the interpretation of signal propagation in complex environments. While arrays have also been employed extensively in sonar systems, the demands of higher resolution and capabilities of digital signal processing algorithms are still further increasing their use. With is increased use of arrays in oceanography and sonar, the attendent demands of processing the data have . also risen. Often, this must be done in r .eal .timeor at least on site, while the array is still deployed. His·torically the needs of geophysical exploration for oil were a prime moyer in the development of array processors. This was principally motivated by the use of large arrays, now with up to 500 channels operating at kilohertz bandwidths, for seismic reflection studies. Fortunately, there are 'many parallels between geophysical exploration for oil andoceanography and sonar, so some inferences about future applications of arrays and array processors may be made. Here we examine some of these potential ~pplications, particularly those ~reas in geophysical exploration related to methods of beam forming, frequency wave function estimation, propagation analysis, and remote sensing. We find that arrays and array processors are integral components making possible studies that could not be reasonably accomplished without them.