Suitability of Correlation Arrays and Superresolution for Minehunting Sonar
Abstract
Towards the possible development of new sonars, particularly a hull-mounted minehunting sonar, work has been done in two areas. The first area concerns arrays-to be called correlation arrays'-that are based on the principle used by correlation telescopes in radio astronomy. The application of this principle might enable a large reduction in the number of sonar array elements. In this area, key results from the literature are reported and some concepts are elucidated with the aid of mathematics. The second area is that of superresolution (SR) and superdirectivity. The former consists of methods by which resolution is obtained that is better than that given by the Rayleigh criterion. In this second area, a more complete literature survey is carried out. A number of SR techniques are briefly described, including Capon's method and an autoregressive moving average (ARMA) model. An important problem for the application of the above techniques to sonar is that both SR and correlation arrays apparently require a high signal-to-noise ratio. For both SR and correlation arrays, the application to sonar faces a further key problem. The problem is that correlations usually exist between the return signals from different targets, and these correlations lead to artefacts and other image defects. Known techniques for decorrelating' targets are described.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2002
- Accession Number
- ADA414771
Entities
People
- David G. Blair
Organizations
- Defence Science and Technology Group