Implementation of continuously steerable beam patterns for a uniform circular projector array

A continuously steerable super-cardioid beam pattern (SCBP) has advantages such as controllable direction, narrower beam width, and higher gain. It is generally implemented with a uniform circular array (UCA). Here, an implementation method of continuously steerable SCBPs is proposed for a projector array. The synthesis and the implementation of the continuously steerable SCBP are studied and analyzed based on a UCA model composed of omnidirectional sources. An improved version of the common method is proposed. It requires fewer array elements and the massive power amplifiers matched to each array element, which reduces the cost and the installation space. Subsequently, a continuously steerable SCBP is implemented with a uniform circular projector array (UCPA). This system is composed of single-sided radiation flextensional transducers and is studied and analyzed with a finite element method, which verified that the proposed method is suitable for the underwater acoustic projector array. Finally, UCPA prototypes were fabricated. The tests demonstrated that the proposed implementation method is a flexible way for the application of the continuously steerable SCBP in the low-frequency emission field.