David L. Carson
480 Rosecrans St., San Diego, CA 92106
This paper discusses the following historic points concerning the concept of velocity control for sonar projector arrays which have strong acoustic interactions among the transducer elements of a given array. (1) Diagnosis of problems that led to the introduction of the concept of velocity control and of including velocity control provisions in the design of the subject sonar projector arrays. (2) Some early observations concerning potential methods to provide velocity control and the corresponding early state of the art for a practical hardware realization of each of these potential methods. (3) An array design approach which specifically included velocity control provisions. (4) A general definition of velocity control in the context of the array design approach of item (3) above. (5) The first specific velocity control method used in the application of the concept of velocity control to the LORAD ARRAY. (6) Two more recent examples of implementation of specific velocity control methods applied to actual high-power, low-frequency, highly interactive projector arrays. (7) An example of the usefulness of inclusion of velocity control considerations in ones thinking concerning active sonar system design when interactive projector arrays are under consideration. (8) A parting thought---the discussion for the above 7 points was in the context of analysis in the steady-state frequency domain; what possible relevance might these experiences have to present design problems concerned more with non-steady-state time domain analysis?